Automotive Gas Filling Compressor Station Block Design

Contents

1 DESCRIPTION AND OPERATION

1.1 Main characteristics

1.2 Composition of CNG

1.3 Process Line Arrangement and Operation

1.4 Compressor suction line

1.5 Natural Gas Compression System

1.6 Natural Gas Drying System

1.7 Compressed gas filling line for vehicles

1.8 Gas accumulator

1.9 CNG automatic control system

1.10 Compressor Cooling System

1.12 Electrical equipment

1.13 Operation of electrical equipment

1.16 Operator console

2 USE AS INTENDED

2.1 Start-up and shutdown rules

2.2 Check of automatic emergency and fire protection of CNSS

2.3 Gas start-up at AGNS

3 Process Control

4 FUELLING OF CARS

4.1 General vehicle refuelling rules

4.2 Start of CNG in operation and procedure of vehicles fuelling

4.3 Standard shutdown of CNG

4.4 Drainage of moisture separators

4.5 Actuation of additional drying system

4.6 Dryer Regeneration

4.7 Operator's actions in emergency situations

4.8 Operator's actions in emergency situations - in case of fire and gas pollution

5 MAINTENANCE

5.1 General Instructions

5.2 Types of Maintenance

5.3 Daily Maintenance

5.4 Maintenance No. 1 (TO-1)

5.5 Maintenance No. 2 (TO-2)

6 BASIC RULES FOR SAFE PROCESS MANAGEMENT AT CNG

6.1 General provisions

6.2 Rules for inspection and repair of process equipment and gas pipelines

6.3 Rules for preparation and repair of electrical equipment

7 INSTALLATION OF THE STATION

Appendix A Pneumatic Schematic Diagram

Appendix B General view of AGCS

Appendix B Operator's Box Equipment

Appendix D Gas accumulator

Appendix D Gas filling column KGZ2-

Appendix E Electrical diagrams

The appendix Zh Layout of Objects of the CNG Filling Station (on 2 sheets)

Main characteristics

1.1.1 The automotive gas-filling compressor station of the block version of AGNKS BI "METHANE" (hereinafter referred to as AGNKS) is designed to fill cargo, passenger gas-cylinder cars and mobile gas tankers, as well as other automotive equipment compressed up to 19.62 MPa (200 kgf/cm2) with natural gas (methane).

AGNCS is designed for operation in climatic conditions of UHL 4.2 as per GOST 1515069.

1.1.2 CNG is designed for refueling 40 cars per day.

1.1.3 CNG process equipment is designed for the maximum natural gas delivery of 120 nm3/h, carried out using a compressor unit of type 6GSH1.62/1.1320G.

1.1.4 Design gas flow rate for filling one vehicle is 60 nm3.

1.1.5 The time required to refuel one vehicle when a gas battery is present is 17... 25 min.

1.1.6 Nominal conditions at the input of CNG:

gas pressure - from 0.3 to 1.2 MPa (from 3 to 12 kgf/cm2) g.;

gas temperature - from minus 5 to plus 30С.

1.1.7 Compressor unit is actuated by motor of asynchronous AIR 225M4. 50 Of Hz. 220/380B. 1M1081. 55 kW power.

1.1.8 On the discharge line of the compressor unit, natural gas is located at:

pressure up to 25 MPa (250 kgf/cm2);

temperature from 30 to 45С.

1.1.9 Gas supplied to CNG from external gas pipeline shall comply with the requirements of GOST 554287.

1.1.10 Compressed gas for fuelling of cars meets the requirements of "Technical specifications for natural compressed gas - fuel for gas-balloon cars" (GOST 2757787).

In accordance with the requirements of GOST 2757787, the maximum gas pressure in the car cylinders is 19.62 MPa (200 kgf/cm2), the gas temperature for backfilling is not higher than 40C (for a hot climatic zone of 45C), the content of mechanical impurities in the gas is not more than 0.001 g/m3; temperature of gas dew point by moisture at pressure of 19.62 MPa (200 kgf/cm2) - minus 30С.

The content of mechanical impurities in the gas in accordance with the requirements of GOST 22387.477, dew point temperature - in accordance with the requirements of GOST 2006083.

1.2 Composition of CNG

1.2.1 The BI40 CNG filling station, consists of four separate blocks: the block box technological (see appendix B, fig. 1, 2), the block box of the operator (see appendix B, fig. 3), the gas accumulator (appendix G, fig. 4) and the gas station (fig. 5).

1.2.2 Process box consists of two compartments - engine compartment and compressor compartment.

Engine compartment accommodates:

electric motor (item 5);

emergency power accumulators of the control system (item 8);

EPO15 heating appliance (pos. 6);

compressor cooling system with fan (item 8).

Compressor compartment accommodates:

compressor (pos. 2);

compressor sensor unit;

vortex pipe;

process part (pos. 4);

gas drying system (pos. 3);

compressor compartment emergency exhaust ventilation system (pos. 2).

The operator's box (see Appendix B, Figure 3) contains:

software operator console;

SHR distribution cabinet;

Relay and control panel of the RTD compressor;

compressor relay unit with intrinsically safe BR input;

gas heating convector KOG501;

operator's workplace.

1.2. 3 The process part of CNG consists of a gas process line, which includes a drying system with a vortex pipe and a filling line, compressor cooling systems, heating systems, compressor automation systems, common-plant automation and electrical equipment.

1.2.4 Gas process line - a complex of gas pipelines and equipment installed on them, necessary for the production of compressed natural gas, which is intended for refueling cars.

Compressor cooling system - a complex of pipelines and equipment necessary for circulation and cooling of coolant, which is intended for:

cooling of compressor unit cylinders (CP);

gas cooling after each compression stage of CP.

The heating system is designed to heat the station premises in the cold season.

1.3 Process Line Arrangement and Operation

1.3.1 Description of the gas train (see Annex A, Figure 1).

Based on the process operations for filling cars with compressed gas at CNG and for their detailed description, the gas production line is divided into:

compressor suction line;

natural gas compression system;

natural gas drying system;

a compressed gas filling line for cars;

drainage line.

1.4 Compressor suction line

1.4.2 Natural gas from the external gas pipeline under pressure from 0.3 to 1.2 MPa (from 3 to 12 kgf/cm2) g, is supplied to the inlet of the CNG, passes through the inlet valve K30 and enters the purification unit consisting of filter FGN25116.

Low-pressure gas filter is designed to clean gas from drip moisture and mechanical impurities. Separation of liquid is carried out due to sharp change of gas flow direction at impact against filter housing wall. The separated liquid accumulates in the lower part of the filter body and is periodically drained through the drain pipe to the condensate collection tank E.

At the top of the filter there is a filter itself having a replaceable filter element. Blowing, flushing, or replacement of clogged filter element is performed after a certain period of time, determined by pressure drop as per readings of sensors DD1 and DD1.1 (in the absence of sensor DD1 - by pressure drop determined by readings of pressure gauge M1 and sensor DD1.1). In addition, KP1 safety valve of KPN0,15 type... 0,3520/20 adjustable for actuation pressure 0.17 kgf/cm2 is installed on the suction line .

Purified gas, through flow metering unit IR1 and electromagnetic valve KE1, is supplied through valve K16 to supply the convector of the operator heating unit and through valve K32 to the compressor suction line.

Gas flow measurement unit consists structurally of housing, narrower device (venturi tube), temperature sensor DT1.1 and pressure sensors DD1.1 and DD1.2.

The gas sent to the compressor is supplied to the reduction unit consisting of the gas pressure regulator PD1 type PP16/0.15... 0,3520/40.

RD1 regulator is adjusted to the pressure so that the pressure per hectare in the compressor suction line is 0.15 kgf/cm2.

After the reduction unit, the gas enters the BT vortex tube of type BT5/0.2120 and the next reduction unit consists of the pressure regulator PD4 of type PP16/0.15... 0,3520/20 designed to provide the necessary gas flow in the suction line in case of a pressure drop at the inlet of the AGNCS.

In the vortex pipe, the gas is divided into two flows - cold and hot. The cold stream has a temperature of 30C lower and a hot stream of 50C higher than the inlet gas temperature.

After the vortex pipe, from the cooled gas with pressure of 1.15 kgf/cm2 abs, moisture contained in it falls out in the form of snow grains and gets into the expander of the OS snow separator of OS4016 type settles in the lower part of its housing. After the snow separator, cold gas passes through the pipe bundle of the moisture separator OB1 and then, being already partially drained due to snow precipitation, it enters the compressor suction. Pressure gauge M4 and pressure sensor DD4 are installed to monitor pressure at compressor suction.

Part of the hot flow exiting the vortex tube is directed through valve K35 to snow separator for snow melting and further to compressor suction line. Another part of the hot stream, passing through the TO heat exchanger, also enters the suction line.

1.4.2 The following are installed on the suction line:

the M1 manometer of MP31R401MPah1.5 type intended for control of pressure of gas on an entrance to the CNG filling station;

K2 manual valve of KTs6250 type intended for sampling;

K30 manual valve of KS20100 type to stop gas supply to CNG;

gas filter FS type FGN25116 for gas purification from solid particles and drip moisture;

measuring unit IR1 of IRG2016 type, for measurement of gas flow rate consumed by CNG;

valve distributor RK1 of type RK2k2080/3... 20 with solenoid control valve KE1 of type EKD 00902, designed to stop gas supply to AGNKS by the signal of the automation system or manually;

valve distributor RK2 of type RK2k2080/3... 20 with solenoid control valve KE2 of type EKD 00902, designed to release gas to the atmosphere at the signal of the automation system or manually;

K32 manual valve of KS20100 type for gas start-up in compressor suction line;

the M2 manometer of MP31R401MPah1.5 type intended for control of pressure of gas before RD1 reducer regulator;

RD1 gearbox-regulator of PP16/0.15... 0,3520/40 type, designed to maintain the gas pressure in the suction line of the compressor 0.15 kgf/cm2;

the M3 manometer of MP31R401MPah1.5 type intended for control of pressure of gas before a vortex pipe;

BT vortex tube type BT5/0.2120 designed to produce cooled gas to freeze moisture and reduce gas pressure to compressor suction pressure;

PD4 pressure regulator of PP16/0.15 type... 0,3520/20 designed to ensure the necessary gas flow rate in the suction line in case of pressure drop at the inlet of the CNSS;

DT1 temperature sensor of TSMU205Ex type, for gas temperature monitoring after vortex pipe;

OS snow separator of OS4016 type, for separation of frozen moisture from gas after vortex pipe;

tube bundle of moisture separator OB1 for condensation of moisture from compressed gas;

heating radiator TO for cooling hot gas flow;

K35 manual valve of KS20100 type, for removal of snow separator;

K18 manual valve of KS20100 type, for gas flow from condensate collection tank to compressor suction;

DT2 temperature sensor of TSMU205Ex type, for monitoring of gas temperature at compressor suction;

KP1 safety valve type KPN0,15... 0,3520/20 to limit compressor suction pressure;

K33 manual valve of KS20100 type used for compressor suction line blowdown;

M4 pressure gauge of MP31P40100kPah1.5 type with DD4 pressure sensor of DNS2 40kPa type, designed to monitor the gas pressure at the compressor suction.

Automatic control system of CNG

1.9.1 Compressor automation system provides:

1) automatic protection with output of generalized light signal "Emergency" and decrypting light signal at:

excess gas pressure at suction line less than 0.005 MPa

(0.05 kgf/cm2) and more than 0.015 MPa (0.15 kgf/cm2);

excess gas pressure at the 1st stage injection is more than 0.42 MPa

(4.2 kgf/cm2), 2 stages more than 1.45 MPa (14.5 kgf/cm2), 3 stages more than 4.6 MPa (46 kgf/cm2 ),

4 stages more than 12.5 MPa (125 kgf/cm2), 5 stages more than 25 MPa (250 kgf/cm2);

coolant flow rate less than 0.55 dm3/s (2.0 m3/h);

excess oil pressure in lubrication system is less than 0.18 MPa (1.8 kgf/cm2);

gas temperature after the 5th compression stage is more than 473 K (200C);

2) locking in cases of:

It is impossible to start the compressor if the coolant flow rate is lower than normal;

shutdown of protection by oil pressure during compressor start-up;

inability to start the compressor without eliminating the cause that caused the emergency shutdown.

1.9.3 Common-station automation system provides:

actuation of emergency forced ventilation system of compartments and sound alarm as per command from gas content monitoring system at concentration of natural gas in air equal to 10% of NPV;

shutdown of the electric motor and compressor unit, supply of the signal "Emergency gas content" at gas concentration of 20% of NPV;

actuation of emergency lighting when the main power supply is switched off, if the main lighting has been turned on;

automatic actuation of emergency power supply of fire alarm systems from 24 V standby DC source (accumulator battery);

automatic cessation of gas release in case of emergency gas pollution of premises or fire;

disconnection of the emergency system of forced ventilation in case of fire by the signal "Fire" from the fire alarm system;

shutdown of the electric motor and compressor unit, disconnection of CNG from the supply gas pipeline and release of gas from the station circuit and gas accumulator through electromagnetic valves by signals "emergency shutdown of CNG," "Emergency gas pollution," "Fire";

elimination of drive motor starting at absence of engine compartment pressurisation.