Boiler house gas supply project with Viessmann boilers

1. Design Input

The working gas supply project of the existing boiler house was developed on the basis of the design task and the state contract No.

The development of the project was carried out in accordance with the requirements of:

- Technical regulations on fire safety requirements

- SP 4.13130.2009 Fire protection systems. Limitation of fire spread at protection facilities.

- SP 6.13130.2009 Fire protection systems. Electrical equipment.

- SP 12.13130.2009 Fire protection systems. Determination of categories of rooms, buildings and outdoor installations by explosion and fire hazard.

- SNiP 42012002 "Gas distribution systems";

- Safety rules for gas distribution and gas consumption systems PB 1252903;

- SP 421012003 "General provisions for the design and construction of gas distribution systems made of metal and polyethylene pipes";

- Rules for arrangement and safe operation of steam and water heating boilers with steam pressure not more than 0.7 MPa and water heating boilers and water heaters with water heating temperature not more than 115 * С;

- SNiP P3576 "Boiler plants" rev.1;

- SNiP 12.04.2001 "Labor safety in construction";

- SNiP 3.02.0187 "Earthworks, foundations and foundation";

- Rules for gas use and provision of gas supply services in the Russian Federation;

- Resolution of the CM of the Republic of Belarus No. 179 of 27.07.01

- GOST 30319.296 "Natural gas. Specifies the compressibility factor. "

2. Brief description of the object

The existing boiler room is located on the territory of the monastery. The boiler room provides heat to the hotel and refectory located on the territory of the monastery. Boiler room capacity - 96 kW. Currently, 2 electric boilers are installed in the boiler room.

The project provides for the installation of two Vitoplex 200 SX2 hot water boilers from Viessmann with a capacity of 120 kW each. Boilers are equipped with automated gas burners.

Newly installed boilers are connected to existing heat networks to supply heat to consumers. The gas supply to the boilers is designed in accordance with specification No. 10/ 36/58/1021/2666 dated 05.10.2010. The gas flow rate will be 28.8 nm3/h.

3. Planning Solutions

Boiler house building - existing, one-story. The dimensions of the building in the plan are 13.25x 12.0 meters. The size of the boiler room is 5.99x5.99, the height is 3.0 m.

The architectural image of the object is dictated by the surrounding situation, relief, the functional purpose of the object and the architecture of the monastery. The boiler room is a one-story rectangular building.

In the decoration of the facades, facing bricks, natural stone "slab," the roof is made of metal.

The existing area of the windows in the boiler room is more than 3% of the volume of the room.

The interior decoration of the rooms is made using non-combustible materials: plaster walls with subsequent painting with water-based paints. Floors - porcelain.

The boiler building has a II degree of fire resistance. External walls are made without insulation with thickness of 640 mm from ceramic full-white brick on cement mortar.

During installation of gas boilers it is necessary to perform the following measures:

- make an independent exit to the street from the boiler room;

- install a louver with area F = 0.15 m2 in the upper part of the door.

Walls separating the boiler room from adjacent ones are classified as 2 type with fire resistance rating of at least REI 45 (1.25 hours), floors - as 3 type REI 45 (1 hour)

Adjacent rooms are utility rooms on both sides that are not designed to accumulate a large number of people.

4. Technical and economic indicators

№№

Description of indicators

Measurement unit

Indicator

1. Installed capacity of Gcal boiler house/h/kW 0.206/240

2. Temperature schedule of boilers 0С 95-70

3. Number of boilers Boiler Vitoplex 200 SX2 2

4. Total boiler room area m2 35.9

5. Internal volume of boiler room m3 107.6

5. Technological solutions

The project provides for the installation of two Vitoplex 200 SX2 hot water boilers from Viessmann with a maximum capacity of 120 kW each, the minimum capacity of one boiler is 36 kW.

The boiler room operates completely in automatic mode without maintenance personnel .

The fuel is low-pressure natural gas, emergency fuel is not provided.

The temperature schedule of the boilers is 9570 0C, which corresponds to the existing temperature mode. Connect the pipelines from the newly installed boilers to the existing main pipelines inside the boiler room. Heat supply to consumers is carried out through existing heat networks.

The design provides for protection of the boiler from lowering the temperature of the return coolant at the inlet to the boiler. For this purpose, mixing pumps are designed, which operate when the temperature before the boiler drops below 60 ° C.

Coolant circulation is performed by existing pumps.

The existing 0.5 m3 tank shall be used for makeup water reserve. Water is supplied to the tank after the softening unit. The tank is filled automatically depending on the water level in the tank. Make-up pump is actuated at pressure decrease in the return pipeline upstream the boilers.

Hot water is prepared directly in the refectory and hotel.

Flue gases are removed from each boiler by separate flue ducts of ∅200 mm made in the inner wall. In the desired part of the gas ducts there are cleaners. Chimneys from boiler to gas ducts are made of thin-sheet galvanized steel with thickness of 1 mm, thermal insulation - heat-insulating piercing mats from mineral wool grade 100 with thickness of 50 mm, cover layer - thin-sheet galvanized steel with thickness of 0.5 mm. Lay the chimney from the boiler to the gas duct with a slope of 0.002% towards the boiler.

Heating system pipelines are made of steel electric welded straight-joint pipes according to GOST 1070491 and steel water and gas pipes according to GOST 326275 .

Insulation of pipelines - heat-insulating piercing mats from mineral wool grade 100 with thickness of 50 mm, cover layer - fiberglass PCT.

6. Gas supply

The gas supply project of the boiler house building was developed on the basis of technical specifications No. 10/ 36/58/1021/2666 dated 05.10.2010.

The estimated flow rate of natural gas is 28.8 nm ³/hour with a gas calorific value of 8000 kcal/m ³, density 0.73 kg/m ³.

The project provides for:

- gas supply of two Vitoplex 200 boilers type SX2 Q = 120 kW from Viessmann in the boiler room;

- equipping two Vitoplex 200 SX2 Q = 120 kW boilers from Viessmann with WG 20N/1C burners Weishaupt Q = 35200 kW ZMLN with WFM 20 combustion manager and WMF SE 512 multifunctional gas multi-unit;

- installation of a thermo-lock valve at the inlet to the boiler room, which automatically closes the gas supply in the room in case of fire;

- installation of disconnecting valves inside at the drops to the boilers, on the blowdown gas pipeline;

- installation of SAKZ autonomous gas content control system in the boiler room complete with gas content detector for natural gas, for carbon monoxide and shut-off gas valve with electromagnetic drive KZGEMU80ND.

Control panel (PK 3), which is part of SAKZ set, to control gas content in the boiler room, be taken to the room where there is permanent personnel.

The gas pressure upstream of the burner is 2.4 kPa. Burners - with automatic control providing automatic start-up and operation at operating parameters. The burner provides starting, blowing, automatic shutdown of the burner and termination of fuel supply at reaching of emergency values of monitored parameters and at occurrence of emergency situations on the boiler with output of alarm signal.

No reserve fuel is provided for this boiler room.

Gas pipelines shall be made of water and gas pipes as per GOST 326275 and steel electric welded straight-joint pipes as per GOST 1070491. Gas pipelines in places of passage through the walls are enclosed in cases.

The area of the window opening in the boiler house is more than 3% of the volume of the boiler house.

Connect the metal structures of the gas pipeline and boilers to the internal grounding circuit of the boiler room. The joint is welded or bolted.

Natural and artificial lighting is provided in the room. Natural ventilation of the boiler house is provided at the rate of three times air exchange per hour. Air supply for combustion in the boiler house is carried out through the louver grille F = 0.15 m ², exhaust ventilation - through the existing ventilation channels 120x120, exhaust of combustion products from boilers through separate gas ducts ∅200.

8. Automation

Viessmann Vitoplex 200 SX2 low-temperature hot water boilers are equipped with Vitotronic 100 controllers and Vitotronic 300 cascade weather-dependent controller, with a full set of protection and control sensors (boiler water temperature sensors, boiler inlet water sensors, maximum and minimum pressure limiters, etc.) that provide boiler control in cascade, weather-dependent mode.

Make-up system is controlled by Ya5111 pump control cabinet.

The project provides for control, control and automation of general-purpose equipment:

- control of circulation and make-up pumps of the heating system;

- maintaining the temperature in the forward and reverse pipelines of the network water according to the temperature schedule;

- maintaining the specified pressure in the return pipeline of the main water;

- pressure monitoring in forward and reverse pipelines of the main water;

- boiler water temperature control;

- protective limitation of temperature, maximum and minimum pressure of boiler water;

- protection of pumps from "dry stroke" mode;

- monitoring of chemically prepared water level in makeup tank;

- automatic control of fuel and air supply to boiler burners;

- control of gas pressure upstream burners;

- alarm of boiler malfunction;

- alarm of pumps malfunction.

The boiler protection circuit automatically stops the fuel supply to the burner at:

- increase or decrease of fuel pressure upstream the burner;

- burner flare failure;

- exceeding the maximum boiler water temperature;

- reaching maximum or minimum boiler water pressure;

- low level of boiler water in the boiler;

- power outage.

The project also provides for the control of gas content in the boiler room (CH4, CO) using the SAKZ system. The carbon monoxide sensor is installed at a height of 1.51.8 m from the floor. Monitoring sensor according to CH4 at the place of probable gas accumulation at the height of 1020 cm from the ceiling. The gas supply valve to the boiler room is blocked in case of gas contamination and voltage loss.

The main part of instrumentation, regulators, actuators is located directly on pipelines in places convenient for maintenance.

Alarm of failure of boilers and pumping equipment shall be brought to the room with round-the-clock maintenance together with alarm for gas automation.

9. Grounding

To protect people from electric shock and to protect against fire, a protective disconnection device (included in the RB set) is used; lighting networks and networks to single-phase power electric receivers are three-wire, to three-phase - five-wire.

In the area of RCD operation, the zero operating conductor shall not be connected to grounded elements and zero protective wire. On the board, zero working and zero protective conductors must be connected under different clamps.

All electrical equipment, start-up equipment, as well as all metal parts not normally energized, but which may be under it due to insulation failure, shall be tapped (grounded).

Housings of stationary single-phase and three-phase electric receivers are grounded by connection to a zero protective wire of the electric network.

The boiler room has an internal grounding circuit with output to the existing external grounding circuit.

The design provides for the installation of the M1 lightning receptacle for the protection of the candle gas pipeline in accordance with the instructions for the lightning protection device SO15434.21-122-2003. Lightning receptacle M1 is connected by lightning outlet B8 to external grounding circuit. The external grounding circuit is made of electrodes made of round steel B16 with a length of 3 meters and connected to each other by strip steel 4x40. The upper end of the vertical grounding conductor shall be buried 0.7 meters from the ground surface.

All connections of grounding current leads and grounding devices shall be made by welding followed by coating with bitumen varnish.

10. Heating and ventilation

Boiler house heating is provided from the internal networks of the building. The temperature inside the boiler room is 50 С.

In the boiler room there is a supply and supply ventilation system with a natural impulse. Air is removed through 3 existing ventilation channels 120x120, air is supplied through the louver grille at the top of the door. The lattice area is 0.15 m2.

The exhaust system ensures the removal of three times the volume of air. The volume of the boiler room is 107.6 m3. The area of the louver screen is accepted on the condition of providing air supply in the amount of 322.8 m3 and ensuring a stable gas combustion process in boiler burners.

The supply air quantity will be 322.8 + 273.6 = 596.4 m3/h. To supply this amount of air, the estimated area of ​ ​ louvers is 0.15 m2 (at a speed of 1.2 m/s ).