Engineering services EXECUTION OF A SET OF WORKS WITH SUPPLY OF EQUIPMENT FOR BIOFUEL-BASED ENERGY INDUSTRY
The environmental situation in Europe and around the world, the rising fuel prices force to turn to the alternative energy sources – the biofuel. Currently, the wood processing waste, tree cutting waste and peat are most commonly used as a biofuel. Many regions have sufficient biofuel resources, which can be effectively used in energy production by introducing the special equipment. The Republic of Lithuania is one of the leading countries in this direction. With a population of three million people, the total capacity of the biofuel-fired boiler houses put into operation so far is more than 800 MW. Axis Industries is a leading company in the production of the biofuel-fired equipment.
A group of specialized companies Axis Industries, Axis Technologies, Bioproektas, BIOPOWER, ECOPOWER manufactures and constructs new biofuel-fired boiler houses, reconstructs the operating biofuel-fired boiler plants, provides a full range of services with regard to putting the facility into operation: design, technical examination, project management, supply and installation of equipment, start-up and commissioning, accumulation of energy losses and energy saving.
This group of companies has already reconstructed and built more than 120 biofuel-fired boiler houses in Lithuania, as well as more than 50 biofuel-fired boiler houses abroad – in Belarus, Latvia, Slovakia, Sweden, Ukraine.
The boiler houses (fuel oil, gas) with boilers of type KE, E, DE, DKVR, BKZ, KVR are changed to the local types of fuel. New biofuel-fired steam and hot water boilers of type KE, KVR, DANSTOKER, RENEWA with a capacity of up to 60 MW are supplied and installed.
For instance, the biofuel-fired CHP was put into operation in 2011 in the city of Alytus. The dismantled hot water boiler PTVM-100 of the district boiler house was replaced with a 5.4 MW biofuel-fired power unit. The biofuel-fired power unit consists of:
– steam boiler BFB 25-45-460 manufactured by RENEWA (Finland) (Dо = 25 t/h, Po = 4.5 MPa, to = 460 °С, t pr.a. = 104-130 оС, texh. = 160 оС, efficiency = 88 %);
– steam turbine MARK 2-H01 manufactured by МАN TURBO (Germany) with a backpressure (Q = 13.9 MW, p1//p2 = 42.0/0.3 bar (f), Ne = 5.4 MW), intended to drive the alternating current generator НТМ-171Е04 manufactured by ELIN Motoren (Austria);
– condensing economizer manufactured by SRE OPCON Group (Sweden) with a heat output of Q ≥ 4.9 MW.
Alytus CHP consumes 15 t/h or 120000 t/year of biofuel. The annual heat production amounts to 111200 MW/year, annual electricity production, 43200 MW/year, and annual operating hours, 8000 h/year.
In 2012, a 10.8 MW biofuel-fired power unit was put into operation at Siauliai CHP, where the wood waste available in sufficient amount is used as a fuel. The boiler capacity is 40.44 MW, the biofuel (wood waste) consumption amounts to 196500 t/year. The Siauliai CHP biofuel-fired power unit consists of the following equipment:
– drum boiler DPCT 50-45-460 manufactured by DP Clean Tech Europe A/S (Denmark);
– steam turbine MARK 2-H01 manufactured by МАN TURBO (Germany);
– steam turbine plant generator НТМ-110С04 manufactured by ELIN Motoren (Austria);
– two condensing economizers manufactured by SRE OPCON Group (Sweden) with a heat output of Q ≥ 4.9 MW.
The heat generation amounts to 35.5 MW/h, electric power generation, 9.47 MW/h, annual heat production, 258789 MW/year, annual electricity production, 75760 MW/year, and annual operating hours, 8000 h/year.
In 2012, the specialists of our company carried out the performance tests of the above-described biofuel-fired power units. As a result, it was concluded that the biofuel-fired power unit had good technical characteristics in the whole range of operating loads. This is a real indicator of a possibility to abandon the expensive natural gas and change to the combustion of the renewable and cheap energy source, as well as of a reliable operation of the equipment.
The projects for small container-type boiler houses (0.5-1.0 MW), modular boiler houses (0.5-4.5 MW) to heat the residential and industrial premises, and large boiler houses with a capacity of several tens of megawatts are implemented. For instance, a project with a 60 MW biofuel-fired boiler has been implemented in Vilnius, this boiler being the most powerful in the Eastern and Central Europe and producing about a tenth of the heat of Vilnius district heating system.
The reconstruction of the boiler houses and their change to the local types of fuel (bark, wood chips, sawdust, peat) do not affect the infrastructure of the boiler houses, i.e. the operating boiler is used, and according to its capacity the furnace is selected, the equipment for fuel storage, handling, combustion is provided, etc. (Fig.1).
A technology has been developed to burn the biofuel – a grate furnace. The main components of the grate combustion technology include the equipment of the storage and system of biofuel supply to furnace, automated grate furnace (with a capacity of 0.5 to 16 MW), ash removal and flue gas cleaning system, system of automation, control and visualization of processes on the computer.
Figure 1 – Typical fuel storage
The technology of biofuel combustion in a fluidized bed is also used, which makes it possible to simultaneously burn different grades of fuel with variable characteristics and moisture content of 30 to 65 %. The advantages of the technology include a small amount of unburned combustible, low СО and NO emissions even at minimum loads.
To increase the efficiency of the biofuel-fired boiler houses, a special equipment can be offered – the contact economizers, owing to which the boiler house efficiency increases by 30 %. The operation principle of the contact economizer is based on the reduction of exhaust gas temperature below the dew point and use of the latent heat of steam formation. This technology has already been implemented in 80 % of all biofuel-fired boiler houses in Lithuania. The investment into economizer pays off within approximately 2-3 years.
Figure 2 – Arrangement of economizer
Various types of biofuel can be used at the biofuel-fired boiler houses: briquettes of different grades of fuel, crushed wood, wood waste, wood chips, bark, straw, milled peat, lignin.
Conclusions:
To upgrade or reconstruct the CHP, boiler houses and implement modern technologies on the existing power equipment in order to produce “green” energy from biofuel, the engineering solutions of the leading companies Axis Industries, Axis Technologies, Bioproektas, BIOPOWER, ECOPOWER are offered. These companies perform a full range of works associated with the supply of the equipment from famous manufacturers, construction, start-up and subsequent warranty maintenance.