www.vep.at PROJECT DESCRIPTION Efficient CHP-plant 150 kw Our pilot plant near Tulln Our custom-made solution for decentralized energy supply with steam technology! V. E. P. Fördertechnik GesmbH Guntramser Straße 229, A-2620 Loipersbach T +43 2635 61991 F +43 2635 61991 30, office@vep.at
CONTENT: 1 General 2 Operating mode 3 General technical data NEUMOT 4 Fuel 5 Biomass combustion plant 6 Operating principle NEUMOT 7 General technical data steam generator 8 Furnace box 9 Flue gas cleaning 10 Control and adjustment control 11 Control function 12 Chimney 13 Employee protection 14 Fire protection measures 15 Ash volume 16 Emission levels 17 CHP- plant components
1. GENERAL Planned is the Installation of a CHP-plant with 150 kw thermal supply capacity with NEUMOT steam generator to generate electricity ( 30 kw) and to provide the thermal base load ( 110 kw over approx. 11 months). NEUMOT stands for a new type of maintenance-free steam motor. Steam supply is done by 12 water-tube generators with defined water level. The classification of the water-tube generators is based on 2 ABV (Regulation for the installation and operation of steam generators) in group 1. The exhaust steam of the steam generator can be used for heat generation (for example: heating, drying chamber,..) 2. OPERATING MODE The CHP is designed for a constant full-load operation throughout the whole season (approx. 11 months), a partial-load operation is not intended. For an overall time of 1 month a standstill for service and maintenance works is intended. The exhaust heat from NEUMOT and the heat from the peak-load generator will be distributed based on heat distribution scheme. In case that the exhaust heat is not used, NEUMOT will be automatically switched off. Page 2
Heat and service water requirements for the connected properties will be met by this buffer storage. During the heating season the heat from NEUMOT can be used for return increase. Outside the heating season the exhaust heat from NEUMOT is provided for domestic hot water resp. for the supply of the drying boxes. 3. GENERAL TECHNICAL DATA NEUMOT Thermal supply capacity: Useable output for the heat consumer: Generated electrical output: 150 kw 110 kw 30 kw Page 3
4. FUEL Water content: up to W 40 Fuel size: wood chips G 30 G 50 according to ÖNORM M7133 Bulk density: S 150 to S 250 Ash content: A 1 A 5 5. BIOMASS COMBUSTION PLANT The wood chips storage room with the existing hydraulically operated moving floor remains resp. will be newly planned and constructed. Fuel transportation screw The new installed fuel transportation screws are driven by gear motor and are equipped with a covered conveyor trough. Cascade with rotary feeder Fuel is fed from the discharge screw to the infeed screw (= stoker screw) via a cascade with a built in verified rotary feeder and overfill detector on the discharge screw and also on the stoker screw. Infeed screw for steam generator (stoker screw) The infeed screw conveyor consists of a simply supported stoker screw with gear motor. The screw is easily replaceable at any time and it is secured via motor protection against overload. 6. OPERATING PRINCIPLE NEUMOT The motor is completely encapsulated. The steam motor drives an asynchronous generator which feeds electricity into an existing network. It is externally excited by the network. In case of power failure, the furnace is regulated to zero down and the steam is diverted via automatically opening of the shut-off valves. In case of a control failure, the network is disconnected from the motor and the steam motor comes to standstill by diverting the steam. The inserted push grate burner is designed that on failure of the fan the exhaust heat is hardly delivered to the steam generator. Page 4
So that an impermissible pressure increase and the response of the pressure safety valves, and also an overheating of the generator walls is excluded. The exhaust steam is condensed and returned to the steam generator via feedwater pump. The steam generator produces 32 bar saturated steam. After that the steam is directed over a jet nozzle (the jet nozzle sucks a part of the exhaust steam from the motor) and then superheated to 350 C. The superheated steam is directed to the motor during the corresponding steam expansion phases. The superheater coils are integrated in the radiation part of the combustion chamber. Because of the special design of the steam generator (water-tube generator with defined water level and one in the generator integrated economizer) the criteria of generator classification group 1 according to the law for installation and operation of steam generators ( ABV 2 section 1) are fulfilled. Therefore no constant control by a generator attendants is required (according to Steam generator operation law 10 section 1d). The control of the system is done by one by the manufacturer (or operator) trained plant attendant. 7. GENERAL TECHNICAL DATA STEAM GENERATOR GREEN STEAM 150 Steam generator: Pressure: Temperature: max. 32 bar max. 240 C Super heater: Pressure: Temperature: max. 32 bar max. 350 C Execution: The combustion chamber is lined in the radiation part, in the combustion chamber are three superheater oils located. Then the hot gas is passed at 12 water-tube generators with defined water level. The flue gas routing is executed with flue tube flange connection and cover plate. The generator material is steel. The generator is fully insulated with rock wool against emission and provided with painted cover. Page 5
The steam generator is executed according to Regulation for installation and operation of steam generators (ABV) of group 1. Legal basis: Regulation for fully automated operation of steam generators (ABD-V) Regulation for the installation and operation of steam generators (ABV) Regulation for pressure equipment control (DGÜW-V) Regulation for steam generator operation law (DKBG) Our approval certificates made by TÜV Austria GmbH, relating to legal regulations of ABD-V, ABV, DGÜW-V, DKBG are visible on request for any interested person. Steam generator capacity heat: 150 kw Water content of fuel: max. 40 % Ambient temperature: 25 C Generator entry temperature: 900 C Emission temperature: < 180 C 8. FURNACE BOX Execution: The fuel combustion is made on a moving step grate consisting of a heat-resistant, scaling-resistant blocks of chrome-vanadium-cast steel. The primary air supply occurs via a rotation speed controlled centrifugal fan, whereby the air supply in the grate is located between the cast segments. The secondary air supply also enters the combustion chamber via a rotation speed controlled fan. Distribution of the secondary air occurs through steel pipes laid in the brickwork. The air supply is taken directly to the combustion chamber, to the postcombustion area. The dimensioning of the combustion chamber and the post-combustion area takes place with regard to a sufficient retention time of the yet unburned material in the hot combustion chamber. The combustion chamber temperature is continually controlled, recorded and displayed on PC. Page 6
The combustion air suction ducts is made from the generator house, therefore a supply air opening is not required. Refractory: Furnace box is made of refractory in multilayer structure schamott A40H and M60H in multi layer construction. Underlying high-temperature isolation is made of ceramics and 100 mm mineral wool isolation. Automatic ash removal: Ash is automatically removed from the combustion chamber by an ash screw conveyor into a side mounted container (approx. 0,5 m³). The ash from the firing box and the multi cyclone will be collected in a ash container with wheels. The container can be rolled out of the building and transported away by an appropriate vehicle. 9. FLUE GAS CLEANING By the use of a flue gas cleaning, the dust can be held below the permissible emission values. For the CHP-plant a cyclone separator will be used. Dust level: 100 mg/nm³ Electrostatic filters will be used if lower limits are required. 10. CONTROL AND ADJUSTMENT CONTROL The distribution system in bus bar technology will be completely wired according to ÖVE standards. All entry and exit points are wired on terminals. All executions comply with the current ÖVE-Regulations (in the latest valid version). The entire control and adjustment control is housed in steel plate cabinets. The wiring to the peripherals is done in flexible, oil-resistant cables. Each motor is equipped with an automatic safety, motor protection relays and secured against phase failure. In the case of an overcurrent or a short circuit a signal contact will be set. The 400 V power circuit can be switched off via a power divider. For the power supply of the control, of the sensors and the limit switches a 24 V power supply is installed. Page 7
Execution of the biomass firing control and the generator control: The system is controlled via PLC-control, which is integrated in the cabinet. The operating parameters, operating hours and any error messages can be read on the PC on-site or via remote maintenance. The electrical control system conforms to the EU-Regulation 73/23/EWG and is therefore entitled, and due to the Low Voltage Regulation 1995 required to carry the CE-mark. 11. CONTROL FUNCTION The control takes over the control of the fuel transport - primary and secondary air - exhaust fan and ash removal. The firing capacity is controlled by the generator pressure. The sensor signals, the control parameters and their plausibility are continuously monitored. Page 8
Optionally a similar error text is displayed and the system shuts down automatically. The control distinguishes a heat-up, operation, firing standby, failure and turn-off phase. The fuel volume is continuously adjusted via control program of the generator system to the required heat output. Thus the different fuel qualities are balanced. The combustion air mass flow is continuously adapted to the fuel mass flow. The adjustment of the combustion air mass flow to the fuel mass flow is such that the residual oxygen concentration in the flue gas is measured and regulated in terms of minimal pollutant concentration. To implement the described control functions all combustion fans are equipped with speed control and the residual oxygen in the flue gas is detected via Lambda probe. The negative pressure in the combustion chamber is controlled by the suction fan speed control and continuously recorded. The suction fan is equipped with a frequency converter. 12. CHIMNEY It is executed as a double stainless steel chimney system. Consisting of: an inner tube, stainless steel material no. 1.4404, thickness 0,5 mm, Ø 250 300 mm, 25 mm mineral fiber isolating layer and outer tube made of stainless steel material no. 1.4301, thickness 0,6 mm. The chimney is made for a continuous thermal load of 400 C, a stability up to 1.000 C is guaranteed. Chimney height: 8 m from base point resp. as required 13. EMPLOYEE PROTECTION In the CHP-plant no employees will be constantly engaged, the system runs fully automatically. The minor operation, inspection, maintenance and service works are carried out by one of VEP Fördertechnik GmbH trained personnel. Page 9
14. FIRE PROTECTION MEASURES Fire protection measures are carried out according to the Technical Guidelines for Preventative Fire Precaution TRVB H 118. The generator room is designed as a separate fire compartment and is separated from the adjacent storage container by a fireproof wall (F 90). Optional a free-standing container is possible, with the respective distance limits according to the local laws and regulations. Return fire protection system The return fire protection system is executed as a rotary valve according to TRVB H 118. It is situated above the stoker screw. The rotary valve is made of non-combustible materials. The custom-fit design and the chamber division by the paddle wheels guarantee lasting and permanent separation of the fuel material flow. First fire extinguishing aid For the first extinguishing aid portable extinguishers according to the Technical Guidelines for Preventive Fire Protection (TRVB) F 124/7 have to be provided. Pressure monitoring device in the combustion chamber The negative pressure in the combustion chamber is continuously measured and regulated to a constant value. If the target value is not corrected, the system shuts down. The failure is stored and recorded on the database. 15. ASH VOLUME With an average ash content of the fuel is to be expected at full capacity of the heating plant an ash volume of about 3 tons per year. In case of appropriate quality of the ash it can be used as a fertilizer. Page 10
16. EMISSION LEVELS Wood combustion plant (13% O2, 0 C, 1013 kpa) The definition of the emission limit values are based on the Regulation for Combustion Plants BGBL 331, 1997. Limit values (guaranteed by rated output a partial load operation is not intended): Dust: 100 mg/nm³, 13% O2 Value of unburned, organic, gaseous hydrocarbons: 20 mg/nm³, 13% O2 Carbon monoxide: 250 mg/nm³, 13% O2 Nitrogen oxide (NOx) indicated as nitrogen dioxide (NO2): 250 mg/nm³, 13% O2 Flue gas temperature: <180 C 17. THE CHP-PLANT IS MADE OF THE FOLLOWING COMPONENTS: Pos. 01 1 pc. Cascade with rotary feeder and stoker screw Length: Canal size: Screw Ø: 1.200 mm 250 x 250 mm 200 mm Complete with: Contact thermostat incl. mounting Light beams for level control Burner screw with channel Torque support for stoker screw Page 11
Pos. 02 1 pc. Push grate burner as combustion chamber Special grate with electro-mechanically section movement Combustion air fan for primary and secondary air supply Connection for stoker screw and ash removal Height adjustable supports Firing capacity: 170 kw Pos. 03 1 pc. Automatic ash removal Complete with: Burner connection flange Control via motor protection switch Central screw shaft with flange bearings Inclined screw conveyor with mounted ash container 2 screw drives over gear motor Pos. 04 1 pc. Steam generator Executed as water-tube generator with defined water level for the operation of thermal engines. Material of the generator: steel produced according to the Regulations of the Steam Generator Law and the Regulation for the Operation of Steam Generators. The steam generator generally consists of: Evaporator with integrated economizer Superheater The steam generator conforms to Group 1 of the Regulation for Installation and Operation of steam generators. Is laid out for the operation/supply of 1 Neumot electricity generator (1 x 30 kw) and for hot water and heating supply. (out-coupling with heat exchanger) All necessary fittings for the operation and the operational control are included. Page 12
Note: The generator is only executed to operate with prepared water according to the specifications from VEP Fördertechnik GmbH. Max. steam temperature: Max. operating pressure: Generated steam power: 350 C (after superheater) 32 bar (of water-tube generator) 200 kg/h Incl. generator sluice resp. process-controlled cleaning function with vibrating automatic Pos. 05 1 pc. NEUMOT steam motor Consisting of: 1 pc. Neumot axial steam piston motor designed for driving an asynchronous generator with electrical power of 30 kw Steam supply lines Stop valves required for the safe operation Valves required for operation Multiple superheater Pos. 06 1 pc. VEP- High-performance cyclone with suction fan Rated power: 200 kw Exhaust gas volume: 475 Nm 3 /h (10% CO2 und N 70%) Capacity: 1.100 m 3 /h with 300 C Speed: 1.500 U/min P: 1,5 kw Complete with: Exhaust fan: multicellular dust extractor that consists of several parallel connected axial cyclones The dust separator is well insulated with mineral wool and a steel jacket. Page 13
The raw gas is evenly distributed to the cyclones and is set in rotation in the swirl devices of the deposition pipes. The cleaned flue gases are passed through the exhaust fan into the clean gas hood and to the chimney. Pos. 07 1 pc. Chimney system Stainless steel chimney Ø 300 mm, total height 8m Consisting of: Chimney stand Normal pipe including the connecting pipe Plaster Muzzle end Pos. 08 1 Control Completely wired power controlled control cabinet for automatic biomass combustion and control of Neumot via PLC; Complete with: Circuit breakers for: Rotary feeder, stoker screw, ash discharge screw, air fan, fire grate and ash removal drive, pumps Temperature limit via safety thermostat in combustion chamber; Automatic speed control of primary and secondary air fan with lambda sonde. Speed control of the flue gas fan with vacuum cell and automatic ignition with hot air blower. Control cabinet built and tested according to Regulations ÖVE/VDE. Page 14
Control unit for connecting and integration of NEUMOT Consisting of:, Control unit - Protection class IP54 - Product Sarel incl. socket Power feedback unit - Product Mitsubishi, Siemens or similar - Voltage 400 Volt - Current < 68 Ampere Material for the production of a functional cabinet for power feedback: - Busbars - Fuses - Terminals for high power and control signals - Cable channels - Wiring - Power cable for input on site Pos. 09 1 Piping and wiring Complete steam piping steam generator Neumot steam generator Complete flue gas piping burner multi cyclone chimney Complete wiring of all sensors and motors in the cabinet Pos.10 1 Visualization Consisting of: - PC (including all necessary components for operation) - Flat screen - Software for process visualization - Profibus data cable for connecting SPS PC - Remote maintenance (via fixed IP-address) Page 15