Architectural and space-planning solutions

The project documentation provides for the installation of an automated modular gas boiler house "AKM Signal 6500" of serial production for heat supply of heating, ventilation and hot water supply systems for residential quarters. The boiler room is classified as category G in terms of explosion and fire hazard. The fire resistance limit of the module is 0,75 hours. The building is a two-story building structure consisting of a metal frame sheathed with three-layer "sandwich panels" with mineral wool insulation. The building is detached on its own foundation. The dimensions of the module in axes are 6000x13500x6700 mm. The exit from the boiler room is provided directly to the outside. The roof of the boiler room with an area of ​​81 m² serves as an easily dumped structure. For the removal of combustion products, the device of individual chimneys with pipes with a diameter of 650 and 600 mm is provided. The height of the chimneys is 26 m. The boiler room is automated and does not require the constant presence of maintenance personnel.

Structural and space-planning solutions

The modular boiler house is designed from easily assembled metal structures with "sandwich" paneling. Metal structures are made of a closed bent profile 80x4, etc. (connections from a bent profile 80x4) according to GOST 30245-2003, the base of the module is made of I-beams 20B1 according to STO ASChM 20-93. Steel structures C245. The outer walls are hinged "sandwich" panels 100 mm thick. The coating is made of "sandwich" panels 100 mm thick on a metal frame. Spatial rigidity and stability of buildings is provided by vertical and horizontal connections. The foundations are taken in the form of a monolithic reinforced concrete slab 200 mm thick, concrete B15, W6, F75 on sulfate-resistant cement. Under the foundation, concrete preparation is provided with a thickness of 100 mm on a sand cushion of 2200 mm. The chimney is free-standing installed on its own foundation. Chimneys in the constructive section were not considered. The foundations for the pipe are columnar from concrete B25, W6, F75 on sulfate-resistant cement. The relative elevation of 0.00 corresponds to the absolute elevation of +18,20 m. In accordance with the report on engineering and geological surveys, heavy silty soft-plastic loams with E = 85 kg / cm2, φ = 15, c = 0,17 kg serve as the base of the sand cushion /cm2. The design resistance of the foundation soils is not lower than R=1,71 kg/cm2. The pressure on the soil under the boiler room does not exceed p=0,2 kg/cm2, under the chimney (max.) p=1,08 kg/cm2. The maximum level of groundwater near the day surface. Groundwater is not found. Soils are moderately aggressive towards concrete of normal permeability in terms of sulfate content. In order to protect the concrete of underground structures, the concrete grade for water resistance is W6 on sulfate-resistant cement, the concrete surface is protected by coating with MBR-65 mastic. The expected average settlement of the building is not more than 2,8 mm. Pipe stability is guaranteed.

Engineering equipment, utility networks, engineering activities

For heat supply, an automated, gas, stand-alone boiler house was designed. According to the degree of explosion and fire hazard, the boiler room belongs to category "G". The installed capacity of the boiler house is 6,5 MW. Roofing is provided as easy-to-reset structures at the rate of 0,03 m² per 1 m³ of the volume of the boiler room. Heat consumers belong to the second category in terms of heat supply reliability. The boiler room is equipped with two water-heating boilers of the Termotekhnik TT100 brand with a heat output of 3000 kW and 3500 kW with Oilon GKP-280M and GKP-400M burners. Estimated heat output of the boiler house, taking into account losses in the networks and auxiliary needs of the boiler house, will be 3,6536 MW, including: for heating - 2,808 MW; DHW avg. - 684,0 kW; for losses in heat networks and auxiliary needs of the boiler house - 161,6 kW. The main type of fuel is natural gas QpН=33520 kJ/m³ (8000 kcal/m³). The scheme for connecting heat networks intended for transporting heat carriers to heat supply systems is independent through heat exchangers. It is planned to control the temperature of the coolant depending on the outside air temperature. Regulation of the boilers and maintaining the necessary parameters of the coolant is provided by the automation of the boiler room. The operation of the boiler room is in automatic mode, without the constant presence of service personnel. The maximum water temperature at the outlet of the boilers is 115°C. The heat carrier at the outlet of the boiler room is water with a temperature of - 95°C. To compensate for thermal expansion of water in the boiler circuit, two expansion tanks V= 1000 l and V= 600 l are provided. To clock the frequency of switching on booster pumps, an expansion tank V = 100 l is installed on the make-up line. Auxiliary equipment is installed in the boiler room: boiler circuit pumps IL150/200-7,5/4 and IP-E 80/130-3/2; pumps of the network circuit of the heating system IL 100/160-18,5/2; DHW circulation pumps MVI 802/PN16; pumps - MNI 204; heat exchangers lamellar heating systems M15-MFM; plate heat exchangers for hot water systems M6-FG; two water storage tanks V=1000 l each; dosing plant for chemical water treatment - Tekna APG603. To account for the consumption of thermal energy, it is planned to install a heat consumption metering unit on the direct and return pipelines of the heating circuit based on electromagnetic flow meters. To remove combustion products, metal individual gas ducts and chimneys are designed with a height of 26 m from the foundation, with a diameter of DN 650 mm (for a 3500 kW boiler) and DN 600 mm (for a 3000 kW boiler). The temperature of the outgoing flue gases is 190°C. The design documentation provides for thermal insulation of heat pipelines, gas ducts and equipment. Gas supply to the boiler house is provided in accordance with the specifications and the letter of amendment. The connection point is a polyethylene designed medium-pressure gas pipeline laid along Highway No. 12. For gas supply to the boiler house, it is planned to lay an underground medium-pressure polyethylene gas pipeline along the intra-quarter territory to the exit from the ground at the boiler room, an above-ground medium-pressure steel gas pipeline along the facade of the boiler room before entering the boiler room. The gas pressure at the inlet to the boiler room is 0,23 MPa. For commercial accounting of the amount of gas, a gas meter of the STG80-400 type is installed. Maximum gas consumption - 759,4 m³ / h. At the entrance of the gas pipeline to the boiler room, the following are installed in series: thermal shut-off valve KTZ-001; gas filter series FN3; solenoid valve series VN3N. To improve the reliability of the power supply to the boiler plant, it is planned to install a SDMO J130K Silent diesel generator in a separate room. Water supply (cold water) and water disposal of the consumers of the facility is provided in accordance with the conditions of connection. Water supply (HWS) is provided from the designed intra-quarter water supply networks D=160 mm through two inputs D=110 mm. The inputs provide for the installation of water metering units according to TsIRV 02A.00.00.00 (sheets 268,269). Guaranteed pressure at the connection point - 26 m of water. Art. Estimated consumption of cold water - 125,44 m³ / day, including: for domestic and drinking needs - 0,04 m³ / day; for technological needs - 125,4 m³ / day once a year. The estimated consumption of cold water for periodic needs (filling the boiler house and heating networks) is 1 m³ / day. The required pressure for the cold water supply system is 51,28 m of water. Art. To ensure the required pressure in the cold water supply network, a booster pumping station was designed. The cold water supply system is ring, single-zone. For the device of the cold water supply system, stainless steel pipes were selected. External fire extinguishing is provided from the designed fire hydrants D = 125 mm, installed on communal intra-quarter networks. Water consumption for external fire extinguishing - 10 l / s. Disposal of domestic wastewater in the amount of 0,04 m³/day, industrial wastewater (emptying the boiler room) - 19,5 m³/day once a year and rainwater with a flow rate of 1 l/s is provided for in the designed intra-quarter networks of combined sewerage. The following systems have been designed for the building: domestic sewerage, industrial sewerage (to drain drainage from process equipment), and external drains. PVC sewer pipes were chosen for the installation of household and industrial sewerage systems. In accordance with the technical specifications for the technological connection of electrical installations of the boiler house to electric networks, two independent mutually redundant power sources of the boiler house are the 1,28st and 1nd sections of the 2 kV switchgear of the 10/220 kV substation. The point of connection to the electrical networks is installed in the ASU-0,4 kV boiler room. The power supply of the boiler house is provided from different sections of the 0,4 kV switchgear of TS No. 31 with two 1250 kVA transformers through two mutually redundant 0,4 kV cable lines of rated section. To back up the power supply of the boiler house in the event of a power failure from the substation, it is planned to install a diesel-electric power station (hereinafter referred to as DPP) SDMO J130K with a capacity of 130 kVA with an automatic start system, as well as uninterruptible power supplies (hereinafter referred to as UPS) in the control system circuits. The estimated recovery time of heat supply to consumers of the boiler house after a power outage from both power sources is no more than 5 minutes. The main consumers of electric energy of the boiler house are: network pumps, recirculation pumps of the boiler circuit, DHW pumps, burner fans and fuel pumps of boiler units, cold water booster pumps, control system. With regard to the reliability of power supply, the complex of electrical receivers of the boiler house belongs to the second category; fire, burglar alarm, gas analyzer, control and dispatching system of the boiler house - to the first category. Restoration of power in case of power failure from one of the sources: for power receivers of the 1st and 2nd category, automatic, by the AVR device in the ASU-0,4 kV boiler room; in case of power supply failure from two sources: for power receivers of the 2nd category - automatic, after starting and entering the operating mode of the diesel power plant of the boiler house; for electrical receivers of the 1st category - automatic from built-in UPS. Estimated electrical load of the boiler house is 80,72 kVA. The power supply scheme adopted in the design documentation satisfies the requirements for the reliability of power supply to electricity consumers of the designed facility. For distribution networks, cables of the VVGng, NYM type are selected. All cables and wiring (starting from the ASU) in three-phase networks are five-core, in single-phase networks they are three-core. The equipment of switchgears and electric networks was checked for long-term permissible load, for the time of disconnection of the damaged section of the circuit by protection devices, for voltage losses, for heating, for short circuit mode. The security system was adopted by TN-CS with a device at the input to the boiler room for re-grounding the neutral conductor and the main potential equalization system. The PE VRU-0,4 kV bus is used as the GZSH. Resistance to direct current spreading of the artificial ground electrode 3,814OM. The generator neutral, lightning protection, GZSH are connected to the ground electrode. A steel lightning rod is installed on the chimney and connected to the grounding conductor through a chimney frame with a 50x5 steel strip. For commercial metering of electrical energy, single-tariff electricity meters Mercury 230 ART2-02 are installed. The project provides for the automation of the operation of the boiler plant AKM "Signal 6500" by automatic control systems "EN-TROMATIK" 50.01 and 50.02. For scheduling the operation of the boiler house, information is transmitted to the central control room via a GSM communication channel. The following information is provided for transmission to the control room: emergency signals in the technological part of the boiler room, a signal about the position of the shut-off valve at the inlet to the boiler room, boiler room gas contamination signals, boiler room fire and security alarm signals, boiler room operation parameters. The heat carrier in the heating system of the boiler room is water with a temperature of 105-70°C. Heating of the boiler room is designed to maintain a temperature not lower than +5ºС and is solved due to heat transfer from process equipment and pipelines and the use of air-thermal curtains. Pipelines to heating devices are laid openly. For the installation of the heating system, steel electric-welded water and gas pipes were selected. Supply and exhaust ventilation is provided in the boiler room, designed for a single air exchange of general ventilation in the cold season and for the assimilation of excess heat in the warm season, as well as providing the air flow necessary for fuel combustion. Air inflow for general and process ventilation is designed through louvered grilles in the outer enclosures. Air removal - through combustion devices and a deflector installed on the roof of the building. In the warm period of the year, supply ventilation is provided with natural motivation, and exhaust ventilation with mechanical and natural. When the maximum allowable air temperature in the boiler room is reached, the exhaust fan is designed to turn on automatically. In the diesel generator room, supply and exhaust general ventilation with a single air exchange is provided.