Architectural and space-planning solutions

The designed boiler house building is one-story, rectangular in plan, without a basement, with dimensions in the extreme axes of 20,0x17,5 m. The maximum height of the building from the planning ground level to the top of the parapet is 8,53 m. The level of the finished floor is taken as a relative mark of 0,000 boiler room, corresponding to the absolute mark of 3.70. The outer walls are made of three-layer sandwich panels. The covering is single-pitched, made of profiled flooring with insulation. The roof is rolled, the drain is external organized. Floor covering - ceramic tiles. The partitions of the diesel generator room are made of sandwich panels. Window blocks - metal-plastic with single glazing. Easily dropped structures are provided - profiled decking and single glazing. Two exhaust towers are designed, each with two exhaust shafts, 30 m high from the level of the clean floor of the boiler house.

Structural and space-planning solutions

The building of the boiler house was designed according to the frame structural scheme with sandwich paneling. The columns of the main frame are made of metal from a rolled I-beam 20K1 and from bend-welded pipes 200x7. The pitch of the columns is 5x8.5m. Steel C245. Covering beams and technological platform - steel from I-beams 35B1 according to STO ASCHM 20-93. External walls - hinged sandwich panels 100 mm thick. Coating - from profiled sheet H114-600-0,8 along the coating beams. The spatial rigidity and stability of the building is ensured by the joint work of the columns fixed in the foundations, the hard disk of the coating, vertical and horizontal connections. The foundations are made of cast-in-situ reinforced concrete tape, united by a 300 mm thick power floor slab, concrete B15, W6, F150. Under the foundation, concrete preparation is provided with a thickness of 100 mm, along a sand cushion with a thickness of 2100 mm. 2 chimneys (2 flue pipes) with an outer diameter of 500 mm and a height of 30 m are fixed on an exhaust tower installed on separate columnar foundations. The metal structures of the exhaust tower are made of racks (pipe with a diameter of 193x4,5, 159x4,5 and 114x4), united by a lattice of 89x4 pipes. The foundations for the pipe are columnar from monolithic reinforced concrete. Concrete B15, W6, F150. Under the foundation, a concrete preparation 100 mm thick is provided, along a cushion of sand and gravel mixture 1000 mm thick, along the compacted soil of the base, composed of loose sands. The relative mark of 0,000 corresponds to the absolute mark of +3.70. In accordance with the report on engineering and geological surveys, sandy and silty fluid sandy and silty sandy loam with E=60 kg/cm2, φ=19, c=13 kPa serves as the base for the foundations of the boiler house, medium-sized loose sand with E=150 kg serves as the foundation for the foundations of chimneys /cm2, φ=30, e=0,75. Estimated soil resistance of the base is not less than R=2,64 kg/cm2. The pressure on the ground is not more than 1,65 kg/cm2 (average pressure 1,12 kg/cm2). The maximum level of groundwater is at a depth of 1,0÷1,5 m. Groundwater is slightly aggressive towards concrete of normal permeability in terms of the content of aggressive carbon dioxide. In order to protect the concrete of underground structures, the concrete grade for water resistance is W6, the concrete surface is coated with hot bitumen twice. The expected average settlement of the building is no more than 0,7 cm. The stability of the pipes is ensured. The calculation of building structures was carried out using the SCAD program version 11.3, manual calculation - according to the formulas of SNiP. Technical surveys of the surrounding buildings (6 buildings) located at a distance of 3 to 20 m were completed. According to the results of the survey, the category of the technical condition of buildings in the surrounding area is category 1 for 2 buildings (20 m), category 2 for 1 building (3 m) and category 3 for 3 buildings (5, 10 and 11 meters). The expected maximum additional draft of buildings and structures located within a 30-meter zone is not more than the maximum allowable values. The project documentation provides for the organization of observations of the existing buildings of the surrounding buildings.

 Engineering equipment, utility networks, engineering activities

 For heat supply of buildings, an automated gas stand-alone boiler house was designed. According to the explosion and fire hazard and the degree of fire resistance, the boiler room belongs to the category "G" and "II". The installed capacity of the boiler house is 22 MW. Facade glazing and flooring are 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. Four water-heating boilers of the COCHRAN THERMAX 5500 brand with a heat output of 5500 kW with combined burners Cochran Equinox 6300 are installed in the boiler house. The calculated heat output of the boiler house, taking into account losses in the networks and auxiliary needs of the boiler house, will be 21,794 MW, including: for heating and ventilation - 20,133 MW; for losses in heat networks and auxiliary needs of the boiler house - 1,661 MW. The main type of fuel is natural gas QpН=33520 kJ/m3 (8000 kcal/m3). The operating mode of the boiler house is only during the heating period. 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 water temperature at the outlet of the boilers is 150°C. The heat carrier at the outlet of the boiler room is water with a temperature of 130°C. To compensate for thermal expansion of the water in the boiler circuit, a Pneumatex pressure maintenance system is provided. To clock the switching frequency of the booster pumps, an expansion tank V = 200 l is installed on the make-up line. Auxiliary equipment is installed in the boiler room: individual pumps of the boiler circuit - WILO IL 100/150-15/2 R, Q=157 m3/h, H=23,7 m of water. st., N=15000 W, n=2900 rpm - 4 pcs.; network circuit pumps - IL 250/380-75/4, Q=320 m3/h, H=42,0 m of water. Art., N=75000 W, n=1450 rpm; booster pump - MVI 1607-6/ PN16 3~, Q=15,6 m3/h, H=65,4 m w.c.; plate heat exchangers for heating systems M15-MFG, 11170 kW, Ru1,6 MPa - 2 pcs.; water softening unit SLS-1252 TW - 2 pcs.; water iron removal plant SLI-1465 TW - 2 pcs. 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 flowmeters Rise. Metal individual gas ducts and chimneys 30 m high were designed for the removal of combustion flue products. Flue gases temperature +190°С. The design documentation provides for thermal insulation of heat pipelines, gas ducts and equipment. Reserve fuel supply is not provided according to the letter of the Committee for Energy and Engineering Support dated November 30.11.2011, 15 No. 18783-11 / 0-1-XNUMX. The designed tank for diesel fuel with a volume of 1000 liters, fuel lines and shut-off and control valves provide for the possibility of operating the boiler house on liquid fuel for 30 minutes. Gas supply to the boiler house is provided in accordance with the specifications. The connection point is a medium-pressure steel gas pipeline with a diameter of 219 mm, laid along the embankment of the Moika River. For gas supply to the boiler house, it is planned to lay a medium-pressure polyethylene gas pipeline with a diameter of 225 mm from the connection point underground, in an open way, to the facade of the boiler house building. Further along the facade of the boiler house, a medium-pressure steel gas pipeline with a diameter of 219 mm is laid before entering the building. The gas pressure at the tie-in point is 0,108 MPa. Steel electric-welded longitudinal pipes according to GOST 10704-91, V-10 (GOST 10705-80*) were selected for laying. For commercial accounting of the amount of gas, a gas meter SG16MT-1600-40-S Du 200 is installed. The minimum gas consumption is 156,2 m3/h, the maximum gas consumption is 2570,7 m3/h. At the inlet of the gas pipeline to the boiler room, the following are installed in series: thermal shut-off valve KTZ-001-200, Du200 Py1,6 MPa - 1 pc.; ball valve gas KSh.Ts.F.200.016, Du200, Ru16 - 1 pc.; gas filter FN 8-1, Du200, Рmax=0,3 MPa – 1 piece; solenoid valve EVP/NC 13 308, DN200, Рmax=0,3 MPa – 1 pc. From the boiler building for heat supply to consumers, heat networks are designed. Thermal loads of consumers: heating - 16,665 Gcal/h, ventilation - 0,647 Gcal/h. Pressure parameters at the connection point P1=6,0 kg/cm2, P2=2,5 kg/cm2. The connection point is the collector of the boiler room. The laying of the heating network is accepted as two-pipe underground channelless, in cases and impassable channels, as well as aboveground along the technical undergrounds of buildings. For laying the heating network, pipes according to GOST 10704-91 made of high-quality carbon steel grade 17GS or 09G2S heat-treated with 100% quality control of steel seams in polyurethane foam insulation, as well as Isoproflex-A pipes with thermal insulation made of polyurethane foam in a waterproofing shell made of polyethylene, were adopted. Compensation for thermal elongations is solved due to the angles of rotation of the route and with the help of bellows compensators. To improve the reliability of the power supply to the boiler plant, it is planned to install a SDMO J275K Nexys Silent diesel generator in a separate room. In accordance with the contract for the technological connection of electrical installations of the boiler house to the electrical networks, the only power source for the boiler house is the 1st section 6kV PS35 / 6kV No. 101. The connection point is in switchgear-0,4kV TP6 / 0,4kV No. 5197 with a 320 kVA transformer. The power supply of the boiler house is provided from one section of RU-0,4kV TP 5197 along one CL-0,4kV APvBbShp-1-4x240 56 m long. To back up the power supply of the boiler house in the event of a power failure from PS101, it is planned to install a diesel-electric power station (hereinafter referred to as DPP) SDMO J275K with a capacity of 250 kVA with an automatic start system, as well as uninterruptible power supplies (hereinafter referred to as UPS) in the control system circuits. Estimated recovery time of heat supply to consumers of the boiler house after a power failure from PS101 is not more than 5 minutes. The main consumers of electric energy of the boiler house are: network pumps, recirculation pumps of the boiler circuit, 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, security alarm, gas analyzer, control and dispatching system of the boiler room - to the first category. Restoration of power in case of power failure of the boiler house from PS101: for power receivers of the 2nd category - automatic, after starting and reaching the operating mode of the diesel power plant of the boiler house; for electrical receivers of the 1st category - automatic from built-in UPS. The estimated electrical load of the boiler room is 207,6 kVA. The power supply scheme adopted in the design documentation does not meet the requirements for the reliability of power supply to consumers of the designed facility in accordance with clauses 1.2.19, 1.2.20 of the rules for the installation of electrical installations (PUE are not included in the list of national standards and codes of rules approved by the order of the Government of the Russian Federation of 21.06.2011. XNUMX, and is not mandatory), but approved by the Energy and Engineering Committee. For the device of distributing networks, a cable of the VVGng type was chosen. All cables and wiring (starting from the ASU) in three-phase networks are five-core, in single-phase networks - three-core.