Description:

Currently, Russian cities have developed gas supply systems for industry and the social sector. Gas is supplied to cities from the Gazprom distribution system with a pressure of 1.2 MPa, and consumers need gas with a pressure of 0.1; 0.3; 0.6 mPa. To meet consumer requirements for gas pressure, gas reducing stations and points (GDS, GRP) are located within the city.

Generating electricity and “cold” without burning fuel

Technical data of power range units

Testing the operation of a pilot electric refrigeration complex at the Yuzhnaya gas distribution station will open up significant prospects for the development of this area of ​​fuel saving and, as a result, reducing the environmental load on the environment.

Thus, only at the Moscow GDS (without the Mosenergo GDS), according to rough estimates, with the help of PEGA it is possible to annually generate more than 250 million kWh of electricity and use about 200 million kWh of “cold” in refrigerators with an area of ​​up to 70 thousand m2, which will prevent the combustion of more than 270 thousand tons of fuel equivalent at the thermal power plant. tons per year with a corresponding environmental effect.

The return on capital investments in the electric refrigeration complex will not exceed two years. Its service life is 60 years.

The cost of generated 1 kWh of energy will not exceed 6–7 kopecks. After the implementation of two or three electric refrigeration complexes, further implementation of the program can be carried out through self-financing from profits.

It seems advisable to develop and implement in a short time an addition to the Moscow energy saving program for 2004 and subsequent years, providing widespread implementation electric refrigeration complexes at the Moscow gas distribution station. This will make it possible to economically use the existing considerable energy resource of “waste” energy from gas pressure at the gas distribution station for environmentally friendly generation of electricity and “cold” using it in refrigerators. The necessary conditions have already been created for this and commercially produced complete equipment is available.

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1. Purpose and design of the gas distribution station

Gas distribution stations (GDS) are designed to reduce the high inlet pressure of natural gas, which does not contain aggressive impurities, to a given outlet pressure and maintain it with a certain accuracy. Through gas distribution stations, natural gas from main gas pipelines is supplied to populated areas, industrial enterprises and other objects in a given quantity, with a certain pressure, the required degree of purification, taking into account gas consumption and odorization.

The block gas distribution station "Energia-1" provides:

Gas heating before reduction;

Gas purification before reduction;

Reducing high pressure to working pressure and maintaining it with a certain accuracy;

Gas consumption measurement with registration;

Odorization of gas before supply to the consumer.

Table 1 shows the main technical characteristics of the Energia-1 AGDS.

Table 1 - Technical characteristics of AGDS "Energia-1"

The gas distribution station AGDS "Energia-1" consists of separate functionally completed blocks. The GDS is equipped with units for gas heating, reduction, gas flow measurement with recording in the device memory and indication, gas odorization, and heating of the control room building. The technological diagram of the Energia-1 AGDS is shown in Figure 1.

The high-pressure gas entering the GDS input passes through ball valves 2.1 and 3.1 to the PTPG-10M gas heater, where it is heated in order to prevent the precipitation of crystalline hydrates during reduction. Heating is carried out by radiation from the burner and the heat of the exhaust gases. The heater has its own reduction unit, in which the fuel gas used to power the burners is reduced to 0.01 - 0.02 kgf/cm 2 .

Heated high-pressure gas enters the reduction unit through ball valves 4.1 and 4.2, where it is preliminarily cleaned of mechanical impurities and condensate, after which it is reduced to low pressure.

From the reduction block, low pressure gas passes to the flow meter string with a diaphragm installed on it. Flow measurement is carried out corrected for pressure and temperature using a Superflow-IIE calculator.

After the metering unit, the gas enters the switching unit, which consists of inlet and outlet lines (ball valves 2.1 and 2.2), safety valves and a bypass line (ball valve 2.3, regulator valve KMRO 2.4). Safety valves protect the consumer system from overpressure.

Figure 1 - Technological diagram of the gas distribution station AGDS "Energia-1"

After the switching unit, the gas enters the automatic gas odorization complex “Floutek-TM-D”. Gas odorization is carried out automatically in accordance with gas consumption. When transferring the gas distribution system to bypass operation, the operation of the gas odorizer is transferred to semi-automatic mode. It is also possible to odorize gas manually; control measurements of odorant consumption are carried out using a measuring ruler according to the calibration table of the working capacity of the odorizer.

2 . Gas heating unit

Heating the gas before reduction is necessary to prevent the precipitation of crystalline hydrates on the working elements of the pressure regulator.

Gas heating is carried out in the PTPG-10M heater, which is structurally a housing in which a tube bundle, a heat generator and a separation chamber are built. The technological diagram of the PTPG-10M gas heater is shown in Figure 1.2.

The heater body is filled with an intermediate coolant - a mixture of fresh water and diethylene glycol in a ratio of 2/3, respectively. The heat generator and tube bundle are immersed in an intermediate coolant, the level of which is controlled by the glass of the level indicator frame.

The heater is equipped with an injection burner. A damper is installed at the air inlet to the burner, which allows you to regulate the completeness of gas combustion. A flame sensor and a gas pilot burner are mounted on the shell. For manual ignition of the burner there is a peephole into which a manual ignition torch is inserted. The gas supplied to the burner enters the nozzle holes, at the exit of which it injects the air necessary for combustion, mixes with it, forming a combustible mixture, and then burns.

The operating principle of the heater is as follows. Fuel gas enters the heater from a low-pressure gas pipeline through a gas control point and is supplied to the burner, where it is burned.

Figure 2 - Technological diagram of the gas heater PTPG-10M

Gas combustion products enter the chimney through the heat generator, from where they are released into the atmosphere. The height of the chimney ensures the dispersion of combustion products to the maximum permissible concentration. The heat of combustion products is transferred through the walls of the heat generator to the intermediate coolant.

Gas from the high-pressure gas pipeline enters the first compartment of the separation chamber, and then into a two-pass tube bundle, where it is heated by an intermediate coolant. The heated gas returns to the second compartment of the separation chamber and enters the GDS technological circuit. Table 2 shows the main technical characteristics of the PTPG-10M gas heater.

Table 2 - Technical characteristics of the gas heater PTPG-10M

3 . Gas reduction unit

The gas reduction unit is an important component of the AGDS and performs its main function - reducing the high inlet pressure of natural gas to a given outlet pressure.

The heated high-pressure gas through valves 4.1 and 4.3 (Figure 1.3) enters the reduction block, where it is first cleaned of mechanical impurities, after which it is reduced. The reduction block consists of two reducing threads: working and reserve. The reducing lines are equivalent both in terms of the equipment that composes them and in terms of throughput, which for one reducing line is 100% of the station's throughput.

4.1, 4.3 - ball valves with electro-pneumatic drive; 4.2, 4.4 - ball valves with manual drive

Figure 3 - Technological diagram of the gas reduction unit

Ball valves 4.1, 4.3, located at the inlet of the reducing threads, have an electro-pneumatic drive; Ball valves 4.2, 4.4, located at the outlet of the reducing threads, have a manual drive. They are designed to disconnect reducing threads if necessary.

The reduction system on each thread has two sequentially located regulators. Reduction is carried out in one stage. The protective regulator RD1, located in series with the working regulator RD2 in the working line, provides protection against exceeding the regulated pressure in the event of an emergency opening of the working regulator. Backup regulators located in the reserve line serve to prevent a drop in output pressure in the event of emergency closure of one of the working line regulators. The system operates using the light reserve method.

The working regulator RD2 is adjusted to the output pressure of the station. The protective regulator RD1 located in series with it and the regulator RD3 of the reserve line are adjusted to a pressure of 1.05·P out and therefore during normal operation of the station their control valves are in a fully open state. The RD4 regulator, located in the reserve line, is adjusted to a pressure of 0.95·P out and therefore is in a closed state during normal operation of the station.

In the event of an emergency opening of the working regulator RD2, the outlet pressure is maintained at a slightly higher level by the sequentially located protective regulator RD1, and in the event of an emergency closure of one of the regulators of the working line, the outlet pressure is maintained at a slightly lower level by the reserve line.

At the gas distribution station "Energia - 1" pressure regulators of the RDU type are installed in the reduction block. Technical characteristics of the regulators are given in Table 3.

Table 3 - Technical characteristics of RDU regulators

RDU pressure regulators are direct-acting regulators “after themselves” and are designed for automatic regulation of gas pressure at main gas pipeline facilities. In regulators of this type, the proportional-integral regulation law is implemented.

4 Gas odorization unit

The gas odorization unit is an automatic complex “Floutek-TM-D”. The complex is designed to supply microdoses of odorant into the gas flow, which is supplied to the consumer, in order to impart an odor to natural gas for timely detection of leaks. The degree of odorization of gas is regulated by changing the time interval between dispensing doses of odorant, depending on the volume of gas passing through the pipeline. Technical characteristics of the complex are given in Table 4.

Table 4 - Technical characteristics of the Floutek-TM-D complex

The odorization complex functionally consists of blocks and devices.

The technological diagram of the complex is shown in Figure 1.4. Designations for the technological diagram are given in Table 1.5

The odorant refilling unit is used to automatically refill the odorant working capacity. The gas pressure regulator and safety valve are used to create an excess pressure (0.2-0.7 kgf/cm2) in the odorant storage tank sufficient to supply the odorant to the odorant filling unit.

The filling pump is designed to automatically supply odorant into the measuring tube of the odorant flow meter. The dosing pump automatically dispenses odorant into the gas pipeline. The odorant flow meter measures the amount of odorant released into the gas pipeline. The flow of odorant into the gas pipeline is controlled through the sight glass of the dropper. The pumps are controlled by a controller installed in the odorization control panel.

From the control panel, you can command the opening or closing of the filling pump or the dispensing of a series of doses by the dosing pump, the filling pump or the evacuation pump.

A - odorant supply in setup mode; B - supply of odorant to the working container; B-to the level indicator; G - supply of odorant to the dosing system of the odorization installation; D - gas for balancing

Figure 4 - Technological diagram of the FLOUTEK-TM-D complex

odorization gas reduction

The selection of the operating mode of the complex is carried out using buttons located on the control panel of the odorization control panel. When you press the “A” or “P/A” button on the control panel, the complex starts working in “Automatic” or “Semi-automatic” mode, respectively. The operation of the complex in both modes is similar, with the exception of entering the value of natural gas consumption into the complex. In the “Automatic” mode, the complex receives gas consumption from the gas metering system at the GDS, and in the “Semi-automatic” mode, the GDS operator enters a fixed gas consumption value.

The operation of the complex begins with checking the tightness of the odorant supply unit and checking the leakage of odorant through the filling pump and dosing pump. Then the filling pump H3 pumps the odorant from the working container into the measuring tube (IT). The IT filling time is set sufficient for the IT to fill to a level equal to the setting parameter. If the filling pump H3 fills the IT above the level of the specified setting parameter, this will not affect the operation of the installation since the calculation of the issuance of odorant doses is carried out according to the actual level in the IT. If the filling pump H3 does not fill the IT to the level specified by the settings, then the operation of the odorization unit stops and an error message is displayed.

The PD-1 sensor of the odorant flow meter measures the level of odorant in the IT. Thus, after filling the IT, the complex fixes the upper level of odorant in the IT. Then the dosing pump H1 begins to supply odorant from the IT into the gas pipeline. The frequency of dosing by the metering pump and, consequently, the amount of odorant released into the gas pipeline is proportional to the flow of natural gas. The level of odorant in the IT decreases, and when the difference between the upper actual and current levels of odorant in the IT reaches the value specified by the setting parameters, dosing stops and the odorant flow meter measures the mass of odorant released into the pipeline and the subsequent period of dispensing doses of odorant is adjusted. The filling pump H3 is then refilled with IT odorant to the level specified by the settings.

After each filling of the IT, the level of odorant in the working tank will decrease, and when the value of this level becomes less than the value specified by the settings (according to the readings of the LE level sensor), the injection pump H2 will turn on, which will pump the odorant from the odorant storage tank into the working tank. Odorization of natural gas will continue. After increasing the level of odorant in the working tank above the value specified by the setting parameters, the injection pump H2 will be stopped.

There is also a manual dropper mode, in which the complex is transferred to completely manual control.

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Federal State Budgetary Educational Institution

higher professional education

"Ufa State Petroleum Technical University"

Department of Automation of Technological Processes and Production

Graduation project

Automation of a gas distribution station

Sterlitamak linear production management main gas pipeline

Student gr. AG 07-01 A.G. Askarova

Supervisor

Consultants:

Ph.D. tech. Sciences, Associate Professor S.V. Svetlakova

Ph.D. tech. Sciences, Associate Professor A.A. Gilyazov

Thesis project 109 pp., 26 figures, 26 tables, 19 sources used, 1 appendix.

GAS DISTRIBUTION STATION, EXCESSIVE PRESSURE SENSOR, METHODS OF PRESSURE CONVERSION, "METRAN-100-Vn-DI", ANALYSIS OF PRESSURE SENSORS

The object of the study is the automation of the gas distribution station of the Sterlitamak linear production department of the main gas pipeline "Energy - 1".

During the research, an analysis of the existing level of automation of the gas distribution system was carried out, and the need to replace excess pressure sensors was substantiated.

The goal of the work is to modernize the automation system of the Energia-1 gas distribution station.

As a result of the study, the Yokogawa EJX430A excess pressure sensor was recommended for use at a gas distribution station for regulation and measurement. An algorithm for the logical control program for the transition of the gas distribution system to bypass mode has been compiled.

Technical and economic characteristics confirm the feasibility of introducing a modern pressure sensor.

There is no implementation.

The effectiveness of the project lies in the high efficiency of the proposed replacement, since the devices being introduced are much better in terms of metrological characteristics.

Definitions, notations, abbreviations

Introduction

1.1 Purpose and composition of the GRS

1.4 Switching unit

1.5 Gas purification unit

1.6 Gas reduction unit

1.7 Gas heating unit

1.8 Gas odorization unit

1.9 Gas metering unit

2. Patent development

2.2 Search rules

2.3 Search results

2.4 Analysis of search results

3.1 Scope of automation

3.2 Information and measuring complex “Magistral-2”

3.3 Pressure conversion methods

4. Modernization of the GDS automation system

4.1 Problem formulation and problem analysis

4.2 Rationale for sensor selection

4.3 Sensor selection

4.4 Algorithm for switching the GDS to bypass mode

5. Occupational health and safety

5.1 Analysis of potential hazards and industrial hazards at gas distribution stations

5.2 Measures to ensure safe and harmless working conditions at the gas distribution station

5.3 Calculation of lightning protection of GDS

6. Assessment of the economic efficiency of modernizing the automation system of the GDS Energia-1

6.1 Criteria for assessing economic efficiency

6.2 Justification of the commercial effectiveness of the project

Conclusion

List of sources used

Definitions, notations and abbreviations

GDS - gas distribution station

LPU - linear production management

MG - main gas pipeline

AWP - automated workstation

ACS - automated control system

RD - pressure regulators

BPG - gas heating unit

APCS - automated process control systems

Instrumentation - control and measuring instruments

TSA - technical automation equipment

SCADA - Supervisory Control And Data Acquisition

TR - strain gauge

SNS - “silicon on sapphire” technology

CNC - “silicon on silicon” technology

ADC - analog-to-digital converter

DAC - digital-to-analog converter

ESD - emergency protection

NPV - net present value

ID - profitability index

IRR - internal rate of return

СО - payback period

Introduction

GDS are designed to supply gas from main and field gas pipelines to populated areas, enterprises and other large consumers. Gas must be supplied to the consumer in a given quantity and under a certain pressure, with the required degree of purification, heating and odorization of the gas (if necessary). The control system must be sufficiently complex to take into account the variety of static and dynamic characteristics of the plant.

With the help of automatic control of the gas distribution system, the highest productivity is ensured with the least expenditure of energy resources, cost reduction and improvement of product quality, the number of maintenance personnel is reduced, the reliability and durability of equipment is increased, and working conditions and safety regulations are improved.

The purpose of this diploma project is technical re-equipment, improvement existing system automation of GDS Energia-1, implementation modern means automation.

The objectives of the diploma project are:

Study of gas preparation technology for supply to consumers;

Analysis of the automation system of the GDS Energia-1;

Modernization of the existing GDS automation system;

Drawing up an algorithm for a logical control program for automatically switching a gas distribution system to bypass mode.

During the work, materials from the Sterlitamak health care facility of GazpromtransgazUfa LLC were used.

1. Technological diagram of the gas distribution station and its characteristics

1.1 Purpose and composition of the GRS

The basic technological process of the Sterlitamak LPU MG LLC GazpromtransgazUfa enterprise is the transportation of gas in the south of the Republic of Bashkortostan and its supply to gas distribution stations, which supply gas to the consumer.

The station is a complex and responsible technological facility of increased danger. The technological equipment and automation equipment of gas distribution stations are subject to increased requirements for the reliability and safety of gas supply to consumers, as well as for industrial safety, as for explosion- and fire-hazardous industrial facilities.

GDS are designed to supply gas from main and field gas pipelines to the following consumers:

Gas and oil field facilities (for own needs);

Facilities of gas compressor stations;

Facilities of small and medium-sized settlements;

Power plants;

Industrial, public utility enterprises and populated areas.

GDS provide:

Gas purification from mechanical impurities and condensate;

Gas heating;

Reducing a given pressure and constantly maintaining it with a certain accuracy;

Gas consumption measurement with multi-day recording;

Gas odorization is proportional to its consumption before supply to the consumer.

The GRS includes:

1) station switching;

2) gas purification;

3) preventing hydrate formation;

4) gas reduction;

5) gas heating;

6) commercial measurement of gas flow;

7) gas odorization;

8)autonomous power supply;

Systems:

1) control and automation;

2) communications and telemechanics;

3) electric lighting, lightning protection, protection against static electricity;

4) electrochemical protection;

5) heating and ventilation;

6) security alarm;

7) gas control.

1.2 Description of the technological scheme

The technological diagram of the automated GDS Energia-1 is presented in Figure 1.1.

The high-pressure gas entering the GDS input passes through ball valve No. 1 to the PTPG-15M gas heater, where it is heated to prevent the precipitation of crystalline hydrates.

Heating is carried out in the coil by radiation from the burner and the heat of the exhaust gases.

The heated high-pressure gas through taps Nos. 6 and 7 then enters one of the reduction lines in the reduction unit, combined with a cleaning unit, where the pressure is reduced to a predetermined value and the process gas is purified from mechanical particles and liquid. The reduction unit consists of two reducing threads: working and reserve.

Figure 1.1 - Technological diagram of AGDS "Energia-1"

In the reduction block, the fuel gas to power the burners is reduced from Pout to 0.1-0.2 Pa.

From the reducing unit, low pressure gas passes to the metering unit.

After the metering unit, the gas enters the odorization unit, and then into the switching unit. Gas enters the switching unit through inlet valve No. 12 and is discharged through the outlet thread onto the spark plug.

The prepared gas is supplied to the consumer at Pout = 0.6 MPa.

1.3 Operating modes and operating parameters of the automated GDS “Energia-1”

GDS operate both autonomously and in the mode of constant presence of service personnel. In any case, the current state of the station is controlled by the gas treatment facility on the territory of which the station is located.

For constant monitoring and control (including automatic) of the state of all local subsystems of the gas distribution system, it is necessary to have a local automated control system for the gas distribution system, connected to the supervisory control and management system of the entire network of gas distribution stations from the main gas distribution facility.

On an automated gas distribution system, 3 control modes are possible:

Fully automatic;

Remote control of actuators from a remote operator's workstation;

Remote manual and remote automatic control actuators from a panel operator's workstation built into the ACS cabinet.

Automatic block GDS "Energia-1" are designed to supply individual consumers with natural, associated, oil, pre-cleaned from heavy hydrocarbons, and artificial gas from main gas pipelines with pressure (1.2-7.5 MPa) by reducing the pressure to a given ( 0.3--1.2 MPa) and maintaining it. Energy stations are operated outdoors in areas with a temperate climate at ambient temperatures from minus 40 °C to +50 °C with a relative humidity of 80% at 20 °C.

The nominal capacity of the Energia-1 station is 10,000 m3/h at the inlet pressure Pin = 7.5 MPa and Pout = 0.3 MPa.

The maximum throughput of the station is 40,000 m3/h of gas at the inlet pressure Pin = 7.5 MPa and Pout = 1.2 MPa. Table 1.1 presents the operating parameters of the automated GDS Energia-1.

Table 1.1 - Operating parameters of the automated GDS "Energia-1"

1.4 Switching unit

The switching unit is designed to switch the gas flow from one line to another line of the gas pipeline, to ensure trouble-free and uninterrupted operation of the gas distribution system in cases of repair or carrying out fire and gas hazardous work. The bypass line connecting the gas pipelines of the GDS inlet and outlet is equipped with temperature and pressure measuring instruments, as well as a shut-off valve and a regulator valve.

The switching unit is designed to protect the consumer's gas pipeline system from possible high gas pressure. Also for supplying gas to the consumer, bypassing the gas distribution system, through a bypass line using manual regulation of gas pressure during repairs and preventative work stations.

The GDS switching unit should provide:

Valves with pneumatic drive on gas inlet and outlet pipelines;

Safety valves with switching three-way valves on each outlet gas pipeline (if there is no three-way valve, they can be replaced with two manual ones with a lock that prevents simultaneous shutdown of the safety valves) and a spark plug for gas relief;

Isolating devices on inlet and outlet gas pipelines to maintain the potential of cathodic protection with separate protection of on-site communications of the gas distribution station and external gas pipelines;

A candle at the inlet of the gas distribution system for emergency release of gas from process pipelines;

A bypass line connecting the gas pipelines inlet and outlet of the GDS, providing short-term gas supply to the consumer, bypassing the GDS.

The GDS bypass line is intended for short-term gas supply for the period of inspection, prevention, replacement and repair of equipment. The bypass line must be equipped with two taps. The first is a shut-off valve, which is located along the gas flow, and the second is a throttling valve-regulator. If there is no valve-regulator, it is allowed to use a valve with a manual drive.

The switching block consists of two valves (No. 1 on the inlet and No. 2 outlet gas pipelines), a bypass line and safety valves.

Through the security valve, gas (through the high-pressure inlet pipeline with a pressure of 5.4 MPa) enters the switching unit, which includes inlet and outlet pipelines with shut-off valves. Ball valves with a lever or pneumatic-hydraulic actuator with local control using an electro-pneumatic control unit are used as shut-off valves. There is also a spark plug valve for releasing gas into the atmosphere.

Ball valves serve as a shut-off device on main gas pipelines, at gas collection and treatment points, at compressor stations, at gas distribution stations and can be used in areas with moderate and cold climates.

The valves are designed to operate at the following temperatures environment:

In areas with a temperate climate from minus 45 to + 50 ° C;

In areas with a cold climate from minus 60 to + 40 ° C;

in this case, the relative humidity of the ambient air can be up to 98% at a temperature of plus 30 °C.

The transported medium through the tap is natural gas, with a nominal pressure of up to 16.0 MPa and a temperature from minus 45 to + 80 °C. The content of mechanical impurities in the gas is up to 10 mg/nm3, particle size is up to 1 mm, moisture and condensate is up to 1200 mg/nm3. The use of taps to regulate gas flow is prohibited.

In the absence of pressure or in the case when it is not enough to shut off the valve using a pneumatic-hydraulic actuator, shut-off is carried out using a manual hydraulic pump. The position of the spool switch pump handle must correspond to the marking: “O” - opening the valve by the pump, “3” - closing the pump, or “D” - remote control, which is indicated on the pump cover.

Taps allow cleaning devices to pass through them. The design of the valves provides the possibility of forced supply of sealing lubricant to the sealing area of ​​the annular seats and spindle in the event of loss of tightness. The system for supplying sealing lubricant to the ring seats of underground valves has a double blocking with check valves: one valve in the fitting, and the second on the valve body in the boss. The fittings have a single design and provide quick-release connection to the stuffing device adapter.

Ring sealing valve seats ensure tightness at pressures from 0.1 to 1.1 MPa.

Rin and Rout from the switching unit are controlled using pressure sensors. To protect low consumer networks, two spring safety valves are installed on the outlet pipeline, one of which is working, the other is reserve. Valves of the “PPPK” type (spring full-lift safety valve) are used. During operation, the valves should be tested for operation once a month, and in winter - once every 10 days, with an entry in the operational log. Valves of this type are equipped with a lever for forced opening and control purging of the gas pipeline. Depending on the setting pressure, safety valves are equipped with replaceable springs.

To allow inspection and adjustment of spring safety valves without disconnecting consumers, a three-way valve of the “KTS” type is installed between the pipelines and valves. A three-way valve of the “KTS” type is always open to one of the safety valves.

The setting of spring safety valves depends on the requirements of gas consumers, but generally this value does not exceed 12% of the nominal value of the outlet pressure.

Figure 1.2 shows the gas switching unit.

Figure 1.2 - Photo of the gas switching unit

The switching unit has the ability to purge the inlet and outlet pipelines through a spark plug valve, the pipeline of which is located outside the GDS site.

The switching unit must be located at a distance of at least 10 m from buildings, structures or technological equipment installed in an open area.

1.5 Gas purification unit

The gas purification unit at the gas distribution station allows you to prevent mechanical impurities and condensate from entering the equipment, process pipelines, control and automation devices of the station and gas consumers.

To purify gas at gas distribution stations, dust and moisture collection devices of various designs are used to ensure gas preparation in accordance with current regulations. regulatory documents manual. The main requirement for a gas purification unit is the automatic removal of condensate into collection tanks, from where it is removed from the GDS territory as it accumulates.

The gas purification unit must provide such a degree of gas purification when the concentration of solid particles with a size of 10 microns should not exceed 0.3 mg/kg, and the moisture content should not exceed the values ​​​​corresponding to the state of gas saturation.

After the switching unit, through the inlet taps, the gas enters the gas purification unit, which is combined with the reduction unit.

The gas purification unit mainly uses oil dust collectors, viscine filters and multicyclone separators. Oil dust collectors are used at stations with high hourly productivity.

An underground tank is installed at the GDS to collect and remove moisture and condensate with automatic control systems for the level and amount of condensate in tanks and dust collectors. The pressure at the inlet and outlet of each dust collector is controlled using pressure sensors.

To purify gas at gas distribution stations, dust and moisture collection devices must be used to ensure gas preparation for stable operation of gas distribution stations equipment and consumers.

Filters 1 and 2, the location of which is presented in section 3, are designed to purify gas from mechanical impurities, as well as to remove condensate. To signal the level in the filter storage tank, low, high and emergency level sensors are installed. When designing units with automatic sludge discharge, the design includes a valve with a pneumatic drive and a shut-off valve that operates at the boundary of the liquid and gaseous fractions.

The gas purification unit includes separator filters or a block of separator filters designed to purify the gas from solid particles and condensed moisture. The degree of purification is 10 microns, efficiency is 99.99%. The cleaning products from the storage tank of the separator filters are automatically discharged into the condensate collection vessel.

The capacity of the reservoir should be determined based on the condition of draining impurities within 10 days.

Tanks must be designed for the maximum possible pressure and equipped with a liquid level indicator.

In order to eliminate the release of condensate and odorant vapors into the atmosphere, it is necessary to take measures for their disposal.

The technological process for collecting gas purification products from tanks must exclude the possibility of liquid spillage and contact with the ground.

Figure 1.3 shows a gas purification unit.

Figure 1.3 - Photo of a gas purification unit

1.6 Gas reduction unit

The reducing unit is designed to reduce the high inlet gas pressure Pin = 7.5 MPa to a low output pressure Pout = 0.3 MPa and automatically maintain the specified pressure at the outlet of the reducing unit, as well as to protect the consumer’s gas pipeline from an unacceptable increase in pressure.

Since the reduction unit is combined with a cleaning unit, gas dehydration, removal of mechanical impurities and condensate removal occur here.

The gas reduction unit at the gas distribution station performs one of the most important functions. Here, the high pressure gas is reduced to a predetermined value and automatically maintained at a certain level. The reduction unit consists of gas control equipment, shut-off valves, reduction lines, an automatic safety system and an alarm system. In reduction unit diagrams the following is used:

Steel control valves for a nominal pressure of 6.3 MPa;

Indirect acting control valves;

Direct acting RD.

To regulate pressure, direct-acting RDs or regulators with analogue control are used. Direct-acting regulators are faster and more reliable, since the intermediate link is eliminated - communication channels and a control device; moreover, they do not require additional energy, since they operate using the energy of the gas flow. Domestic manufacturers produce regulators that provide pressure regulation with an accuracy of up to 2.5%.

At high-capacity gas distribution stations, control valves are more often used, since they allow you to quickly change the regulated pressure at the valve outlet and have a large selection of standard sizes.

Proportional regulators of the RD type are used as command devices for indirectly acting valves. Control valves come in two types: normally open (pressure is applied to the top of the membrane) and normally closed (under the membrane).

All control valves consist of a control body (valve) and a diaphragm actuator connected through a stem to the valve spool. The gas outlet pressure in all types of control valves is set by loading the valve stem with a spring.

The reduction unit is designed to reduce the inlet pressure from 5.4 MPa to 0.6 MPa and supply gas through a low-pressure pipeline to the linear networks of gas consumers.

In the GDS reduction unit, the number of reducing lines should be at least two (one reserve). It is allowed to use three reduction lines of equal capacity (one backup).

In the reduction unit (Figure 1.4), if necessary, it is possible to provide a low-flow line for operation during the initial period of operation of the GDS.

Figure 1.4 - Photo of the reduction unit

Reducing lines within one reduction unit must be equipped with the same type of shut-off and control valves. Gas reduction lines must be equipped with relief valves.

Reducing lines must have automatic protection against deviations from operating parameters and automatic switching on of a reserve.

1.7 Gas heating unit

A gas heating unit or GSU is designed for indirect heating of gas to a given temperature; it is used as part of a gas distribution system to eliminate hydrate formation during gas reduction and maintain the gas temperature at the output of the gas distribution system at a given value, as well as to provide coolant for space heating systems or other possible heat consumers.

BPGs are designed for operation in areas with temperate and moderately cold climates, as well as in areas with cold climates.

The standard size of the heating unit as part of the GDS should be determined based on the conditions for ensuring the required gas temperature at the GDS outlet, normal operation of the station equipment and the prevention of icing. In the case of using a PPG in a heating circuit, it is necessary to take into account the additional thermal load.

The gas is heated in a shell-and-tube heat exchanger using an intermediate coolant heated in a hot water boiler. The coolant, depending on the thermal power of the unit, is heated to 95 °C and supplied to the shell-and-tube heat exchanger, where heat is transferred to the heated body (gas), then the cooled coolant from the return heat pipe with a temperature of up to 95 °C is supplied to the inlet of the water heating boiler. If there is an additional heating circuit, the coolant is taken from the return heat pipe.

Structurally, the gas heating unit consists of a boiler house block and a heat exchanger block.

The equipment of these units is located in a box hermetically divided into two compartments: the boiler room compartment (category D) and the heat exchangers compartment (category B-1a). The box is made of panels and has a removable roof, which allows for quick installation and repair of heavy and large equipment. Block box resistance to seismic loads up to 9 points. The compactness of the unit and complete factory readiness allow transportation, installation and commissioning work to be carried out in the shortest possible time.

The required thermal power is provided by two hot water boilers in the boiler room compartment to increase the reliability of the unit. In the event of a failure of one boiler, the second can ensure the operation of the station in emergency mode.

Circulation pumps are installed at the inlet of water heating boilers and operate under the control of a pump control and protection device in the operating time distribution mode. If one pump fails, a serviceable pump ensures 100% performance. To protect the system from exceeding the internal hydraulic pressure, the boilers are equipped with safety relief devices (discharge is carried out into the expansion tank).

The power supply of the PPG is carried out from an industrial network of 220 V/50 Hz, or 380 V/50 Hz. Power is supplied through an input cabinet equipped with residual current circuit breakers. The input cabinet is installed in the boiler room compartment.

1.8 Gas odorization unit

A condition for the safe operation of main gas pipelines, vessels, apparatus, equipment and instruments is the timely detection of gas leaks. The presence of gas in premises can be detected using automatic devices and systems. However, most in a simple way Detection of gas in the air is determined by its smell. For this purpose, in our country and a number of other countries, gas is given a special unpleasant odor (odorized) by introducing ethyl mercaptan in an amount of 16 g per 1000 m3. Gas is odorized at the headworks or at the field gas distribution station.

Thus, after the metering unit, the gas enters the switching unit where it is odorized and then through the pipeline it passes to the consumer’s low-level networks.

To maintain a given degree of gas odorization, an odorant is introduced at the outlet of the gas distribution system using various devices. At automated gas distribution stations, the universal gas odorizer of the UOG-1 type is most often used. Below is table 1.4 with the technical characteristics of the gas odorizer UOG-1.

Table 1.4 - Technical parameters of the odorizer "UOG-1"

The following requirements apply to odorants:

Odorants at concentrations used for odorization must be physiologically harmless;

When mixed with gas, odorants should not decompose or react with the materials used in the gas pipeline;

The combustion products of odorants must be completely harmless and non-corrosive;

Odorant vapors should be slightly soluble in water or condensate;

Odorants must be volatile (to ensure their evaporation in a flow with high pressure and low temperature).

Ethyl mercaptan (C2H5SH) largely satisfies these requirements. The amount of odorant required to be introduced into the gas flow is determined by the threshold of its concentration at which a pungent odor is felt in the room. For natural gas, the signal norm is assumed to be 1% by volume. To maintain a given degree of gas odorization, the odorant is introduced into the flow using special devices called odorization units, which are divided according to the method of introducing the odorant into units with direct introduction of liquid odorant into the gas under pressure or by gravity and units for displacing odorant vapors with the gas flow. The first type includes droplet odorants, in which the odorant is introduced into the gas flow in the form of drops or a jet. The amount of odorant introduced is controlled manually using a needle valve. The operation of the odorizer is monitored through a sight glass.

Gas supplied to industrial enterprises and power plants may not be odorized by agreement with the consumer.

If there is a centralized gas odorization unit located on the main gas pipeline, it is allowed not to provide a gas odorization unit at the gas distribution station.

The odorization unit is installed at the station exit after the bypass line. Odorant supply is allowed with both automatic and manual adjustment.

It is necessary to provide containers for storing odorant at the gas distribution station. The volume of containers should be such that they can be refilled no more than once every 2 months. Refilling containers and storing odorant, as well as gas odorization, must be carried out in a closed manner without releasing odorant vapors into the atmosphere or neutralizing them.

1.9 Gas metering unit

The gas metering unit is designed for commercial gas metering (measuring its flow). The number of measurement lines depends mainly on the number of gas outlet pipelines from the gas distribution system.

After the reduction unit, the gas is supplied through a pipeline to the gas metering unit. Commercial metering of gas consumption for each consumer and gas metering for personal needs is carried out at a gas metering station. The unit provides gas flow measurement, flow rate correction based on temperature, pressure and compressibility coefficient, gas quality analysis, and data recording.

The measurement of gas passing through the GDS is based on the variable pressure differential measurement method. This method is characterized by the fact that when a restriction device is installed in a gas flow, the pressure drop across it depends on the amount of gas passing through. The restriction device can be installed on the high or low side of the GDS.

The pressure drop is measured by a calculator, the type of which is selected simultaneously with the calculation of the restriction device. The restriction device is connected to the sensors of the computer via connecting lines.

Currently, the majority of the fleet of flow meters at gas metering stations of OJSC Gazprom consists of measuring and computing systems that measure flow by the pressure drop across the diaphragm. Some gas distribution stations still use mechanical recorders. But, even despite the high accuracy of microprocessor-based computer systems (error no more than 0.5%), the total error of the flow meter unit due to the diaphragm error is at least 2.5%.

The error in flow measurement can be reduced by replacing the diaphragms with other types of flow sensors - turbine, rotary or vortex. Such complexes provide an overall gas metering error of no more than 1.5-2.5% and do not require frequent replacement, like diaphragms.

When qualifying gas metering at a gas distribution station as commercial, it is necessary to determine not only the quantity, but also the quality of the gas metered in accordance with the requirements for self-supporting gas metering stations. In-line analytical instruments allow you to obtain information about gas quality with minimal discreteness.

Humidity and gas density are determined, respectively, by in-line moisture meters (dew point temperature meters) and density meters. The caloric content of the gas is measured by a flow calorimeter. The use of flow chromatographs allows you to obtain complete information on the composition of the gas, calculate density and calorie content. The content of sulfur and hydrogen sulfide is determined by laboratory sulfur meters.

If it is necessary to regulate the gas flow at the GDS output, flow regulators with analogue control are used. To implement proportional integral differential control of gas flow, instead of correctors, so-called “flow computers” are used, which, in addition to regulating and correcting gas flow, can receive information from in-line analytical equipment and transmit information in the form of reports to the control room.

2. Patent development

2.1 Selection and justification of the subject of search

This thesis project discusses pressure conversion methods, selection and implementation of an excess pressure sensor.

One of the most important measured parameters at the GDS is pressure. At the moment, Metran-100-Vn-DI excess pressure sensors are installed at the Energia-1 GDS; the possibility of replacing this sensor with a modern EJX430A excess pressure sensor, the operating principle of which is based on the resonance method, is being considered. Therefore, when conducting a patent search Special attention was devoted to the search and analysis of excess pressure sensors with the resonant method of pressure conversion.

2.2 Search rules

The patent search was carried out using USPTU funds according to sources of patent documentation Russian Federation and for foreign funds.

Search depth five years (2007-2011). The search was carried out using the International Patent Classification (IPC) indices:

G01L 9/16 - Measurement of constant or slowly varying pressure of gaseous and liquid substances or bulk materials using electrical or magnetic elements sensitive to mechanical pressure by detecting changes in the magnetic properties of bodies under load;

G01L 13/06 - Devices and instruments for measuring the difference between two or more fluid pressures using electrical or magnetic elements,

sensitive to mechanical pressure.

The following sources of patent information were used:

Full descriptions of patents of the Russian Federation;

Documents of the reference and retrieval apparatus;

Official bulletin of the Russian Agency for Patents and Trademarks “Inventions. Utility models" (2007-2011).

2.3 Search results

The results of the patent search are shown in Table 2.1.

Table 2.1 - Patent search results

2.4 Analysis of search results

Let's consider the analogues given in Table 2.1.

No analogues have been identified for patents G01L 9/16 and G01L 13/06.

The Yokogawa company (Japan) is the developer of DRHarp technology (resonant pressure transducer with a silicon resonator) and therefore today there are no analogues in our country.

Patent for the sensing element of the 3051S sensor: United States patent: 6082199. The new DPHarp sensing element is based on the well-known “frequency resonance” principle, which can be clearly demonstrated using the example of a string: the tension of the string is controlled by its own vibration frequency (tone). When the string is tensioned, its tone (natural frequency) becomes higher, and when it is loosened, it becomes lower.

A silicon diaphragm is used as an elastic element, on which two sensitive elements are located. Sensitive elements - resonators are located so that their deformations differ in sign when a pressure difference is applied to the sensitive element.

The change in the natural frequency of the resonators is directly proportional to the applied pressure. Excitation of oscillations and transmission of the frequency of mechanical oscillations into an electrical frequency signal occurs by placing double-circuit resonators in a constant magnetic field and passing an alternating one electric current through the resonator body in the excitation circuit.

Thanks to the effect electromagnetic induction, an alternating EMF appears in the measuring circuit with a frequency equal to the oscillation frequency of the measuring circuit resonator. Feedback The excitation circuit along the measuring circuit, together with the effect of shifting the frequency of forced oscillations towards the resonant frequency, ensures constant correspondence of the frequency of electrical oscillations to the resonant (natural) frequency of mechanical oscillations of the resonator body. The natural frequency of such an unloaded resonator is usually about 90 kHz.

Today, DPHarp sensing elements are the only serious alternative to capacitive and piezoresistive measurement methods. The large margin of accuracy and stability of the DPHarp sensing element confirmed the feasibility of using EJX430A differential pressure sensors.

3. Automation of GDS Energia-1

3.1 Scope of automation

3.1.1 Automation levels

As a rule, monitoring and control systems are two-level systems, since it is at these levels that direct control of technological processes is implemented.

Lower level - includes various sensors to collect progress information technological process, electric drives and actuators for implementing regulatory and control actions. Sensors provide information to local programmable logic controllers. As a rule, management problems are solved at this level.

To reduce the human factor associated with the incorrect operation of complex technological equipment, it is necessary to introduce automation tools based on a human-machine interface that is intuitive to humans, which should summarize, structure and systematize information.

The upper level includes, first of all, one or more control stations, which represent a dispatcher/operator workstation. PCs of various configurations are mainly used as workstations.

The GDS operator's workstation is necessary to increase the efficiency of the operator's (dispatcher's) interaction with the system and reduce his critical errors during control to zero; reducing the time for processing information and searching for the necessary information; improving the quality of control and accounting of analog and discrete parameters; management of technological equipment, i.e. increasing operator efficiency.

All components of the control system are interconnected by communication channels.

The interaction of the workstation with the self-propelled control system of the gas distribution system is carried out via an Ethernet network.

The block diagram is shown in Fig. 3.1.

Figure 3.1 - Block diagram of the GDS monitoring and control system

Functions performed by the automated workplace of the self-propelled control system of the gas distribution system:

Providing a mechanism for user registration to protect against unauthorized control of GDS technological equipment;

Display on the monitor of mnemonic diagrams of the crane piping and technological equipment of the gas distribution station in the form of video frames, made according to the principle of multi-level nesting from general to specific;

Visualization on the monitor of information from sensors and alarms about the state of the technological equipment of the gas distribution system, as well as information coming from local automatic control systems in real time (gas heaters, etc.);

Display of analog parameters, including in the form of trends over

a given period of time, and control of their reliability;

Display of analog parameters settings with the ability to change them;

Displaying the states of actuators and monitoring their serviceability;

Remote control of actuators (taps, fans, discrete throttle valve);

Registration and archiving of information with an agreed-upon retrospective depth about the state of the crane piping of the gas distribution station, the state of process equipment, emergency and pre-emergency situations, operator actions (on controlling process equipment, changing the settings of process parameters);

Display and registration of gas consumption accounting for several metering units (instantaneous, daily, monthly consumption), changing configuration parameters, including taking into account chemical composition gas;

Display of current alarm and warning information in the current alarm log;

Sound notification of the operator about an emergency situation, including emergency and warning sound alarms;

Automatic generation and printing of operator logs;

Maintaining archives of event logs, trends and operator logs.

The introduction of such systems at gas distribution stations is of particular importance, as it allows ensuring effective work GDS in specified modes, improve the quality of work, ensure accident-free operation and environmental safety, and increase labor productivity.

GDS automation tools are designed to improve the reliable and stable operation of GDS and ensure continuous gas supply to consumers.

3.1.2 Automation functions

Complex technical means automation installed on technological equipment provides:

Switching node control, including:

1) measuring the pressure and temperature of the gas at the inlet of the gas distribution system, comparing the measured values ​​with the specified technological and emergency limits, generating and issuing warning and emergency alarms;

2) measuring the pressure and temperature of the gas at the outlet of the gas distribution system, comparing the measured values ​​with the specified technological and emergency limits, generating and issuing warning and emergency alarms;

3) signaling the position of the taps of the switching unit, the security tap of the gas distribution station; remote (from the local GDS console and from control center) control of the taps of the switching unit, the security valve of the gas distribution system and automatic shutdown of the gas distribution system in case of accidents. Control of the gas purification unit, including: measuring the pressure drop in the separator;

4) signaling the minimum and maximum permissible liquid level in the separator; remote and automatic control of the valve on the liquid discharge line depending on the liquid level in the separator filter;

5) warning alarm of the maximum liquid level in collection containers;

Control of the hydrate formation prevention unit, including:

1) measuring the pressure and temperature of the gas at the outlet of the heating unit;

2) signaling the position of the valves at the inlet and outlet of the heating unit, the valve on the gas supply line bypassing the heater;

3) automatic and remote control of cranes;

4) signaling of heater operation from the heater control system;

5) heater failure alarm;

Control of the gas reduction unit, including:

1) monitoring the position of valves on reduction lines;

2) automatic and remote switching on/off of reduction lines, including backup and auxiliary lines;

3) gas pressure alarm on pressure reduction lines between sequentially installed control devices;

4) automatic regulation of gas pressure supplied to consumers;

Commercial gas metering for each consumer, including:

1) measurement of parameters common to all consumers and introduction of the necessary constants; gas pressure measurement; gas temperature measurement;

2) gas flow measurement (gas meter with pulse output);

3) calculation of gas consumption;

Control of the gas odorization unit, including:

1) signaling the minimum level in the odorant storage tank;

2) control of dosed supply of odorant into the gas;

3) signaling the presence of odorant flow;

4) recording the amount of introduced odorant;

Crane control on the bypass line, including:

1) position of the valve on the bypass line;

2) remote (from the local GDS console and from the control center) control of the crane on the bypass line;

Signaling the state of the power supply unit, including:

1) signaling that the main power source is turned off; signaling the status of the backup power source;

2) signaling of switching to a backup source;

3) accounting for electricity consumption;

Commercial gas metering for own needs, including measurement of:

1) parameters and introduction of necessary constants;

2) gas pressure;

3) gas temperature;

4) gas consumption (gas meter with pulse output);

Monitoring the state of the gas distribution system, including:

1) identification of emergency situations using appropriate algorithms, activation of emergency protection of the gas distribution system;

2) temperature measurement in the instrumentation block;

3) signaling the presence of pre-explosive concentrations of natural gas in the premises of the gas distribution station;

4) fire alarm;

5) alarm for intrusion into the territory of the GDS and into the premises of the GDS;

6) alarm for odorant leaks;

7) control of operation and control of the cathodic protection station (measurement of voltage, current, potential and regulation of output voltage/current);

Self-diagnosis technical condition SAU GDS, including:

1) troubleshooting analog sensors with a unified output;

2) monitoring the integrity of actuator circuits;

3) failure detection, accurate to a typical input/output module;

4) identifying a lack of communication with the upper level of management;

Presentation of information:

1) generation and delivery of information, including warning and emergency alarms, to the local monitoring and control panel, activation of the sound detector on the gas distribution system;

2) generation and issuance of warning and emergency signals to a remote control panel, activation of the sound detector;

3) generation and delivery of information via communication channels to the control center;

4) processing, synchronization and execution of commands coming from the local console and from the control center;

5) remote (from the control center) shutdown of the gas distribution system;

Secondary functions:

1) switching from the main power source to a backup one without disrupting the operating algorithm and issuing false signals;

2) protection from unauthorized access to information and management;

3) event logging.

3.1.3 ESD system

The reliability of the functioning of safety systems for hazardous industrial facilities depends entirely on the state of electronic and programmable electronic systems related to safety. These systems are called ESD systems. Such systems must be able to maintain their functionality even in the event of failure of other functions of the gas distribution control system.

Let's consider the main tasks assigned to such systems:

Preventing accidents and minimizing the consequences of accidents;

Blocking (preventing) intentional or unintentional interference in the technology of an object, which can lead to the development of a dangerous situation and initiate the operation of an emergency protection system.

Some protections require a delay between alarm detection and tripping.

At the GDS, a number of technological parameters are continuously monitored, the emergency values ​​of which require shutting down and blocking the operation of GDS facilities. Depending on the parameter or condition by which the protection was triggered, the following can be performed:

Automatic shutdown of the gas distribution system;

Closing the taps of the switching unit, security tap;

Control of a crane on a bypass line;

Switching to a backup source.

A test mode is provided for all protection parameters. In test mode, a protection flag is set, an entry in the protection array is set, and a message is transmitted to the operator, but control actions on the process equipment are not generated.

Depending on which controlled parameter the protection is triggered, the system must:

Disabling GDS facilities;

Closing the valves;

Disabling certain auxiliary systems;

Turning on light and sound signaling devices.

To ensure safe operation, gas pipelines are equipped with shut-off and control valves, safety devices, means of protection, automation, blocking and measurement.

In front of the burners of gas-fired installations, automatic fast-acting shut-off valves with a class A seal tightness in accordance with the state standard and a closing time of up to 1 second are provided.

A loss of electrical power from an external source causes the valve to close without additional energy input from other external sources.

The design of shut-off and control valves, safety devices, electrical circuit protection devices, safety automation, interlocks and measurements complies with the requirements of regulatory and technical documentation agreed with the Gosgortekhnadzor of Russia. The design of shut-off and control valves and safety devices ensures that the valve is at least class B tight and resistant to the transported medium during the service life established by the manufacturer.

Shut-off valves installed outdoors have an electric drive designed to correspond to the outside temperature range specified in the technical data sheets for electric drives, and must also be protected from precipitation.

The design of gas pressure regulators must ensure:

Proportional band not exceeding ± 20% of the upper limit of output pressure setting for regulators;

Dead zone of no more than 2.5% of the upper limit of the output pressure setting;

Time constant (transient control process time during sudden changes in gas flow or inlet pressure), not exceeding 60 s.

Relative unregulated gas leakage through the closed valves of double-seat regulators is allowed no more than 0.1% of the nominal flow rate; for a single-seat valve, the tightness of the valves must correspond to class A according to the state standard.

The permissible unregulated gas leakage when using butterfly valves as control devices should not exceed 1% of the capacity.

The accuracy of operation of safety shut-off valves must be ± 5% of the specified values ​​of controlled pressure for safety valves installed on gas distribution stations.

Safety relief valves must be capable of opening when the specified maximum operating pressure is not exceeded by more than 15%. The pressure at which complete closure of the valve occurs is established by the relevant standard or specification for the manufacture of valves. Spring relief valves must be equipped with a device to force them to open.

The permissible gas pressure drop across the filter is set by the manufacturer. Filters must have fittings for connecting differential pressure gauges or other devices to determine the pressure drop across the filter.

Aggregate protection of the gas distribution system must ensure its trouble-free operation and shutdown when the controlled parameters exceed the established limits.

The algorithmic content of the ESD functions consists in the implementation of the following condition: when the values ​​of certain technological parameters characterizing the state of the process or equipment go beyond the established (permissible) limits, the corresponding object or the entire plant must be shut down (stopped).

The input information for the group of ESD functions contains signals about the current values ​​of controlled technological parameters, arriving at logical blocks (programmable controllers) from the corresponding primary measuring transducers, and digital data about the permissible limit values ​​of these parameters, arriving at the controllers from the operator's workstation console. The output information of the ESD functions is represented by a set of control signals sent by the controllers to the executive bodies of the protection systems.

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Short description

Use of gas in natural gas allows you to intensify and automate production processes in industry and agriculture, improve sanitary and hygienic working conditions in production and at home, and improve the health of urban air basins. The low cost of gas, combined with the convenience of its transportation and the absence of the need for warehousing, ensures high economic effect replacing other types of fuel with gas. In addition, natural gas is a valuable raw material in the chemical industry. industry in the production of alcohol, rubber, plastics, artificial fibers, etc. The undeniable advantages of gas and the presence of its significant reserves create conditions for the further development of the country's gas supply.

Introduction………………………..……………………………………
Section 1. Data on the technology of an industrial facility………………………………………………………………………………….
General information about the industrial facility……………………….
Characteristics of hazardous substances involved in the production process………………………………………………………...
Analysis of the technological process of a gas supply facility……..
List of main technological equipment in which hazardous substances are handled………………………………………………………..
Section 2.Analysis and assessment of hazards of an industrial facility...
Information about known accidents and malfunctions…………………….
Analysis and assessment of the conditions for the occurrence and development of accidents at the facility…………………………………………………………..
Determination of possible causes and factors contributing to the occurrence and development of emergency situations…………………
Determination of probable scenarios for accidents at the facility………………………………………………………………..
Calculation of probable zones of action of the main damaging factors under various accident scenarios……………………………………………………..
Estimation of the possible number of victims, taking into account those fatally affected among personnel and the population in the event of accidents.........
Assessment of the amount of possible damage in the event of an accident…………
Conclusions on the section……………………………………………………………..
Section 3. Ensuring the industrial safety requirements of the facility………………………………………………………………..
Technical solutions aimed at preventing depressurization of equipment and preventing emergency releases of hazardous substances……………………………………………………………
Technical solutions aimed at preventing the development of accidents and localizing emissions of hazardous substances……..
Technical solutions aimed at ensuring the explosion and fire safety of the facility…………………………….
Automatic control systems, interlocks, alarms and other safety equipment………
Section 4. Conclusions and suggestions for the course project…………
List of the most dangerous components of the facility……………...
Proposals to improve the safety of the facility and implement measures aimed at reducing the risk of accidents......
Section 5. Research part of the course project……………
Gas leak through the water seal……………………………………
Section 6. List of references…………………..

Attached files: 1 file

Inclusion of a reserve reducing thread in the event of failure of one of the workers;

Disabling a failed reducing thread;

Alarm about switching of reducing threads.

Each gas distribution system must be stopped once a year to perform maintenance and repair work.

The procedure for admitting unauthorized persons to the gas distribution station and the entry of vehicles is determined by the division of the production association.

At the entrance to the GDS territory, a sign must be installed with the name (number) of the GDS, indicating its division and production association, the position and surname of the person responsible for the operation of the GDS.

The security alarm system available at the gas distribution station must be kept in good condition.

ORGANIZATION OF GDS OPERATION

Technical and methodological management of the operation of gas distribution stations in the production association is carried out by the corresponding production department.

Technical and administrative management of the operation of gas distribution stations in the division is carried out by the head of the division in accordance with the established distribution of responsibilities.

Direct management of the operation of the GDS is carried out by the head (GDS engineer) of the linear maintenance service.

Operation, current and overhaul, reconstruction and modernization of equipment and systems, technical supervision should, as a rule, be carried out:

1. linear maintenance service - technological equipment, gas pipelines, buildings and structures, heating and ventilation systems, territory and access roads;

2. instrumentation and automation service - instrumentation, telemechanics, automation and alarm systems, flow metering points;

3. electrochemical protection service (site) - equipment and devices for electrochemical protection, power supply, lighting, lightning protection, grounding;

4. communication service (section) - communication means.

The distribution of responsibilities between services can be adjusted by the production association based on the structure of the association and local characteristics.

The forms of operation and the number of personnel for each individual GDS are established by the production association depending on the degree of its automation, telemechanization, productivity, category (qualification) of consumers and local conditions.

Operation of the GDS must be carried out in accordance with the operating instructions for each GDS, developed by the department based on the requirements of these Rules, operating instructions for the equipment included in the GDS, and other technical documentation.

Equipment, shut-off, control and safety valves must have technological numbering applied with indelible paint in visible places in accordance with the GDS circuit diagram.

The direction of gas movement must be indicated on the gas pipelines of the gas distribution system, and on the shut-off valve controls the direction of rotation when opening and closing.

The change in pressure at the outlet of the gas distribution system is carried out by the operator only by order of the department manager with a corresponding entry in the operator’s log.

The GDS must be stopped (measures are taken to close the inlet and outlet valves) independently by the operator in the following cases:

Rupture of technological and supply gas pipelines;

Equipment accidents;

Fire on the territory of the gas distribution station;

Significant gas emissions;

Natural Disasters;

At the request of the consumer.

The gas distribution system must be equipped with alarm systems and automatic protection against excess and reduction of outlet pressure.

The procedure and frequency of checking the alarm and protection must be provided for in the operating instructions for the gas distribution system.

Operation of the gas distribution system without alarm and automatic protection systems and means is prohibited.

If there are no automatic protection systems at the GDS in operation, the procedure for equipping them with these systems is established by the association in agreement with the local authorities of the Glavgosgaznadzor of the Russian Federation.

The frequency and procedure for changing and checking safety valves must be provided for in the operating instructions for the gas distribution system.

Automation and alarm devices may be turned off only by order of the person responsible for the operation of the gas distribution system for the period of repair and adjustment work with registration in the operator’s log.

Gas control systems at gas distribution stations must be maintained in good condition. The procedure and frequency of checking the settings of these systems is determined by the operating instructions for the gas distribution system.

The shut-off valves on the GDS bypass line must be closed and sealed. Operation of the gas distribution system along the bypass line is allowed only in exceptional cases during repair work and emergency situations.

When working on a bypass line, the constant presence of an operator at the gas distribution station and continuous recording of the outlet pressure are required. The transfer of the gas distribution system to work along the bypass line must be recorded in the operator’s log.

The procedure and frequency of removal of contaminants (liquids) from gas purification devices is determined by the division of the production association. At the same time, the requirements of environmental protection, sanitary and fire safety must be observed, and the entry of contaminants into consumer networks must be prevented.

Gas supplied to consumers must be odorized in accordance with the requirements of GOST 5542-87. In some cases, determined by contracts for the supply of gas to consumers, odorization is not performed.

Gas supplied for the gas distribution system’s own needs (heating, operator’s home, etc.) must be odorized. The heating system of the gas distribution station and operator's houses must be automated.

The procedure and accounting of odorant consumption at the gas distribution station are established and carried out in the form and within the time frame established by the production association.

GDS must provide automatic regulation of the gas pressure supplied to the consumer with an error not exceeding 10% of the set operating pressure.

MAIN GDS UNITS

1. switching unit;

2. gas purification unit;

3. hydrate formation prevention unit;

4. reduction unit;

5. gas metering unit;

6. gas odorization unit.

The GDS switching unit is designed to switch the high-pressure gas flow from automatic to manual pressure regulation along the bypass line, as well as to prevent an increase in pressure in the gas supply line to the consumer using safety valves.

The GDS gas purification unit is designed to prevent the ingress of mechanical (solid and liquid) impurities into process and gas control equipment and control and automation equipment for the GDS and the consumer.

The hydrate formation prevention unit is designed to prevent freezing of fittings and the formation of crystalline hydrates in gas pipelines and fittings.

The gas reduction unit is designed to reduce and automatically maintain the specified gas pressure supplied to the consumer.

The gas metering unit is designed to record the amount of gas consumption using various flow meters and counters.

The gas odorization unit is designed to add substances with a strong unpleasant odor (odorants) to the gas. This allows you to promptly detect gas leaks by smell without special equipment.

ction ›› Gas equipment ›› Automatic gas distribution stations ›› Energia-1 Gas distribution station Energia-1

Automatic block gas distribution stations "Energia" are designed to supply individual consumers with natural, associated, oil, pre-cleaned from heavy hydrocarbons, and artificial gas from main gas pipelines with pressure (1.2-7.5 MPa) by reducing the pressure to a given (0. 3-1.2 MPa) and maintaining it. Energy stations are operated outdoors in areas with a temperate climate at ambient temperatures from –40 °C to +50 °C with a relative humidity of 80% at 20 °C.

TU 51-03-22-85. Permission of the Federal Service for Environmental, Technological and Nuclear Supervision of the Russian Federation No. RRS 00-17765 dated September 8, 2005.

The station provides the following main functions: gas heating, additional gas purification from mechanical impurities, reduction of high gas pressure to operating pressure, flow measurement with multi-day recording, gas odorization before supply to the consumer.

The nominal throughput of the Energia-1 station for gas under conditions in accordance with GOST 2939-63 is equal to 10000 m3/h at the inlet pressure Pin = 7.5 MPa (75 kgf/cm2) and Pout = 0.3 MPa (3 kgf/cm2 ).

The maximum throughput of the station is 40,000 m3/h of gas at the inlet pressure Pin=7.5 MPa (75 kgf/cm2) and Pout=1.2 MPa (12 kgf/cm2).

Automatic gas distribution stations (AGDS)

Automatic block gas distribution stations "Energia" are designed to supply individual consumers with natural, associated, oil, pre-cleaned from heavy hydrocarbons, and artificial gas from main gas pipelines with pressure (1.2-7.5 MPa) by reducing the pressure to a given (0. 3-1.2 MPa) and maintaining it.

The main functions of the AGDS also include: gas heating, gas odorization, gas flow measurement, automatic control of station operating modes, issuing emergency and warning signals in case of violations of the operating mode to the dispatcher or operator console.

GDS Energia are operated outdoors in areas with a temperate climate at ambient temperatures from –40 °C to +50 °C with a relative humidity of 80% at 20 °C.

There are several types of GDS according to their purpose:

• stations on a branch of the main gas pipeline (at the final section of its branch to a populated area or industrial facility) with a capacity of 5-10 to 300-500 thousand m3 per hour;
• field gas distribution system for the preparation of gas (removal of dust, moisture) produced in the field, as well as for supplying gas to a populated area close to the field;
• control and distribution points located on branches from main gas pipelines to industrial or agricultural facilities, as well as to supply the ring system of gas pipelines around the city (with a capacity of 2-3 to 10-12 thousand m³ per hour);
• automatic gas distribution system for supplying gas to small settlements, state and collective farm villages on branches from main gas pipelines (with a capacity of 1-3 thousand m³ per hour):
• gas control points (GRP) (with a capacity of 1 to 30 thousand m³ per hour) to reduce gas pressure and maintain it at a given level in urban high- and medium-pressure gas networks;

According to GRS, they are classified as hazard class 3.

Location of the industrial facility – Rostov region, Taganrog, the population of which is 40,000 people. The distance of the GDS from the populated area is 400m. The climatic zone in which the object is located, Rostov-on-Don, the predominant wind direction is western. A situational map-scheme of the area where the facility is located is shown on sheet No. 1 of the graphic part.

1. Characteristics of hazardous substances involved in the production process

The GDS facility is classified as a hazardous production facility due to the circulation of hazardous substances such as methane, odorant and methanol.

The characteristics of hazardous substances at the gas distribution station are presented in Table 1.1.

Table 1.1 Characteristics of hazardous substances.