Gas supply to the city and district boiler house

Contents

Introduction

1. Development of low and high pressure networks and network equipment units based on the general construction area plan

1.1 Characteristics of the construction area

1.2 Characteristics of gaseous fuel

1.3 Determination of annual gas demand

1.3.1 Household consumption

1.3.2 Gas consumption in utilities and public enterprises

1.3.3 Annual gas consumption for heating, ventilation and centralized GVA

1.3.4 Annual gas consumption for local heating plants

1.3.5 Annual gas consumption by industrial enterprises

1.4 Determination of gas hourly flow rates

1.4.1 Hourly gas flow rate for domestic consumers

1.4.2 Hourly gas consumption by municipal and public enterprises

1.4.3 Hourly gas flow for heating, ventilation and centralized GVA

1.4.4 Hourly gas flow to local heating plants

1.4.5 Hourly gas consumption by industrial enterprises

1.5 Hydraulic calculation of low pressure network

1.6 Hydraulic calculation of high pressure network

1.6.1 Preliminary calculation of ring diameter by approximate constraints

1.6.2 Calculation of emergency modes

1.6.3 Calculation of normal mode

1.7 Selection of pressure regulators for FRG

1.8 Boiler house gas supply

1.8.1 Boiler house characteristics

1.8.2 Determination of boiler room gas flow rate

1.8.3 Calculation of boiler room GRU equipment

1.8.4 Hydraulic calculation of boiler room gas pipeline

2. Automation of GRS

2.1 Brief description of the object

2.2 Scope of Control and Automation in GMS

List of graphic part

Sheet 1. General plan of the city

Sheet 2. Low Pressure Network Diagram

Sheet 3. High Pressure Network Diagram

Sheet 4. Boiler room plan. Cut. Facade

Sheet 5. Plan, section GRP (GRU) boiler house

Sheet 6. Boiler Room Gas Line Axonometric Diagram

Sheet 7. Automatic Control System

Sheet 8. Economy

Sheet 9. SMR technology

Sheet 10. CIW Organization

Introduction.

Gas as a fuel is known to have a number of advantages over other fuels, namely: gas has a high calorific value from 14665 to 41900 kJ/m3, high efficiency (when used in gas-fuelled plants), is characterized by convenience of storage, ease of transportation, simplicity of gas-burner devices for its combustion, smoke-free combustion, absence of waste, which contributes to less pollution of the air-spirit both in boiler houses and in the surrounding atmosphere in the area of boiler plants.

In the history of the development of gas networks, there is the fact that until 1917 natural gas was not mined in Russia and the gas industry did not exist. However, after 1917, gas plants were built that worked on coal and the use of associated gases produced from oil fields began. In 19411942, the first natural gas pipeline was built from gas fields in the area of ​ ​ Buguruslan to industrial enterprises in Kuibyshev with a length of 160 km.. At the same time, the Elshanka-Saratov gas pipeline was built with a length of 16 km.. The capacity of the first two gas pipelines reached 1 ml m3 per year. In 1946, the Saratov-Moscow gas pipeline with a length of 840 km was commissioned. from pipes with a diameter of 300 mm. to supply the central regions of the city. Since 1945, there has been an increase in the growth of the construction of gas pipeline systems. In 1976, for the first time in world practice, the construction of gas pipelines from pipes of large diameters began in our country: 1000 mm, 1200 mm, 1400 mm.. From the construction of individual gas pipelines, a step was taken towards the creation of gas networks. Currently, natural gas production in Russia is approximately 600 million. m3 per year, which gives rise to the widespread use of network gas both in cities, industrial enterprises, and in rural areas. Today, the gasification of Russia is about 62%. Worldwide (in particular in rural areas), the use of propane - butane, which is explosion and fire hazard and is poorly regasified in winter, is declining. In this regard, to ensure the maximum use of natural gas by industrial enterprises, housing and communal facilities of cities, working villages and rural settlements, a large amount of work is required to design and build gas networks at the modern level, ensuring environmental protection and high economic efficiency when using them.

In accordance with the assignment in this diploma project, it is necessary to develop a gasification project in Shchigra, Kursk Region, that is, we will consider gasification of residential, industrial quarters and utilities of this city. Let's take a more detailed look at gasification of residential quarters and boiler house, which will be reflected in the graphic part of the diploma project .

1.3. Determination of annual gas demand.

The annual consumption of gas for household, communal and public needs depends on a large number of factors: gas equipment, improvement and population of apartments, equipment of urban institutions and enterprises, the degree of service to these institutions and enterprises, coverage of consumers with centralized hot water supply, climatic conditions.

Most of these factors are not accurately accounted for, therefore, annual gas consumption is calculated according to average standards. In the annual standards of gas consumption in apartments, we take into account that the population partially eats in buffets, canteens and restaurants, and also uses the services of utilities.

The annual gas consumption of Shchigra is the basis of the diploma gas supply project.

All urban gas consumption can be grouped as follows:

- domestic gas consumption (consumption of gas in apartments);

- In municipal and public enterprises;

- for heating and ventilation of residential and public buildings;

- industrial.

2.1 Brief description of the object.

The solution of the problem of gas supply at the modern stage of technology development is associated with the introduction of automation and telemechanics in the urban economy. The integrated application of these means leads to the creation of ACS by gas distribution and gas consumption processes, which will provide optimal and efficient production and technological regimes in the city gas supply.

In order to correctly solve the problems related to the automatic regulation and management of urban gas supply systems, it is necessary to take into account the features of non-stationary gas transmission processes in the gas distribution network and, first of all, in high and medium pressure urban gas pipelines. From this point of view, the methodology of analytical calculations and modeling of the dynamic characteristics of urban gas networks is acquired.

The main task of the automatic control system is to maintain the required gas pressure in time at various points of the city gas network. This task can be successfully solved by analyzing the unknown gas flow in gas distribution lines.

In the diploma project, automation of the gas distribution station (GRS) is being developed. From the main gas pipeline, gas enters the city gas supply systems through the GRS. Gas pressure is reduced to the value required for gas supply system and kept constant at GPU. GMS equipment is calculated for the maximum possible pressure in the main gas pipeline - up to 6.4 MPa. Since the GRS is characterized by a large throughput, for reliability, gas throttling is carried out in three lines and on each of them two RD-100-64 controllers are installed, tuned to different pressures. Flowmeters are installed to measure the amount of gas flowing. As a result of the fact that it is impossible to allow interruptions in gas supply to cities, towns and large industrial consumers, the protective automation of the RRS is created on the principle of redundancy, and not disconnection of gas flow in case of failures of regulatory equipment.

Automation is carried out according to the principle of watchless maintenance. For this, the GRS is equipped with instrumentation, protective automation, remote control of disconnecting devices and alarm.

GRS is serviced by an operator at home. In case of malfunctions on the GRS, the operator's house receives light and sound unencrypted signals, when received, the operator goes to the station for troubleshooting.

The GPU diagram allows in emergency cases or during repair works to supply consumers with gas along the bypass line (bypass) with manual control of gas pressure.

2 Scope of control and automation in GDS.

Control and automation of gas distribution systems shall be provided in the scope corresponding to the "Regulation on Technical Operation of Gas Distribution Stations of Main Gas Pipelines." In accordance with this provision, the GDC is equipped with an automatic pressure control system; systems and devices for monitoring, control, alarm and protection, providing complete automation of all technological processes.

The GRS automation diagram shall include:

a) gas reduction by direct gas pressure regulators;

b) automatic maintenance of the gas pressure at the GPF outlets within the specified limits;

c) automation of safety of gas heaters, boiler plant;

d) measurement of pressure and temperature at the inlet and outlet of the GDC, gas temperature after the heaters, accounting of gas consumption by consumers with data transmission to the linear production control dispatcher via the telemechanics channel;

e) emergency and warning alarm on the operator's board, to the operator's house (during home maintenance) and to the line-production control manager;

f) remote control of cranes of GDC connection unit, GDC security crane. In some cases, remote control of cut-off valves on reduction and measurement lines is used, automatic switching of measurement lines depending on the gas flow at the outlet of the GRS;

g) accounting of gas pressure at inlet and outlet of reducing threads;

h) automatic discharge of condensate from gas separators.

The GRS protection system against excess or decrease of gas pressure is made with the help of specially adjustable pressure regulators, which are sequentially connected on each (working or standby) reduction line.

The gas flow rate for each line is taken into account either by a chamber diaphragm of DK type, CSS, which works together with a DSS type differential pressure gauge with the Superflow microprocessor complex, or by a gas meter.

Control of gas temperature at the inlet to and at the outlet of MT is performed by balanced bridge of MT type and thermal transducers of TCM type, which are placed on signalling board.

The condensate level in the gas separators is controlled by the automatic complex "Watershed 1," and the level in the condensate collection tanks is carried out by a buoy level meter of the UBPG type.

Automation of gas heaters is provided in the scope of complete delivery. The fault signal of each gas heater is transmitted to the alarm board.

Remote control of valves with pneumatic drive is provided at the inlet to and outlet from the RMC using control units EPPU2M and units of VK81K type from the control room.

In case of MV operation mode violation, the light-and-sound alarm is transmitted in the following cases:

a) at increase and decrease of gas pressure at the inlet and outlet of the FRS;

b) upon termination of odorant supply;

c) in case of boiler room equipment failure;

d) in case of failure of heaters;

e) in case of voltage loss;

f) when the security alarm is activated.

The signal is decrypted on the instrument panel installed in the control room of the SGR reduction building.

Standby network pumps are also provided for operation. Standby heating pumps are activated automatically when the pressure in the common pressure line is reduced. The control equipment of the network pumps is installed on the automation panel in the boiler room. When the water level in the expansion tank of the boiler house decreases, gas cut-off to the boilers is provided.

To ensure the normal operation of the GPU, an automatic system is used to prevent unacceptable deviations in gas pressure of the "Protect2" type, which provides monitoring of gas pressure, switching on the standby line in operation with an unacceptable decrease in gas pressure in the working line.

5. Safety and environmental friendliness of design solutions.

Introduction.

In the section of the diploma project "Safety and environmental friendliness of design solutions," based on the analysis of hazardous and harmful production factors, measures were developed to ensure safe working conditions and protect the natural environment.

The gas economy of the city is a network of gas pipelines, GRP (gas distribution point), GRS (gas distribution station) communal, residential enterprises, and the housing stock of the city. Gas farming is potentially hazardous due to the possibility of gas leaks and the formation of gas-air mixtures and their explosions. In addition, incomplete gas combustion, poorly organized removal of combustion products and insufficient ventilation of premises where gas devices are installed can lead to suffocation and poisoning of people. Therefore, the design, construction and operation of any gas facility is subject to strict control, regulated by regulatory documents, the main of which are: "Safety Rules in the Gas Industry" of the State City Technical Supervision and "Construction Rules" (SNiP).

5.1 Characteristics of the object.

The diploma project has developed a project for gas supply to the city and the boiler house from the high-pressure gas pipeline.

The following materials will be used in the works of the designed object:

- oxygen and acetylene;

- paints;

- petrol;

- diesel fuel, etc.

Mechanisms:

- bulldozer;

- excavator;

- compressor;

- autocrane, etc.

The manufacturing process includes the following steps:

- earthworks;

- installation works;

- gas pipeline test;

- commissioning of the gas pipeline.

Earthworks include: breakdown of the route, installation of inventory fences, cutting of vegetal soil, tossing and filling of the gas pipeline with soil, backfilling of the gas pipeline.

Installation of the gas pipeline includes: unloading of pipes with their layout along the route, straightening of damaged pipe ends, installation of a base for pipes, assembly of pipes into links on the edge of the trench, welding, quality control of welded joints, digging of pits in places of welding, laying of pipe links on the bottom of the trench, installation of shaped parts, anti-corrosion insulation of the gas pipeline.

When testing the gas pipeline, it is blown with compressed air, gas pipelines are tested for strength and tightness, the final test of the gas pipeline and the delivery of as-built documentation.

When the gas pipeline is put into operation, it is carried out: removal of inventory fences, planning of the territory, sowing of lawn grasses.

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