BBI Zeneris

Investment Project – Starting up production of ecological energy from renewable energy sources in Wałcz.

The planned investment is characterized by the use of advanced technological solutions. Production of charcoal from timber of deciduous trees (biomass) consists in gasification (destructive distillation ) of timber. Thermal energy is generated in the process, partly spontaneously and partly as a result of the combustion of wood distillation gas, which is not used by most producers or used only to a limited extent. The presented investment includes a patented method of using waste thermal energy for the production of electricity. Electrical power produced in cogeneration using two technologies will be classified as renewable energy. The plant will have 7.23 MW of installed capacity, making it one of largest renewable energy projects built independently from professional power providers.

The direct objective of the project, which is under way, is to start producing electricity from renewable resources and to produce charcoal.
A strategic objective is to join the group of renewable electrical energy and heat producers, and to build and strengthen the position of a leader in the charcoal production sector in terms of its costs. The plant will produce:

• Electrical energy from renewable sources;

• Charcoal and charcoal briquette (biomass, which when combusted does not cause additional emission of CO2),

and will bring about a reduction of the emission of greenhouse gasses, including CO2, by ca. 37,000 Mg per year.

The construction commenced in 2007 and is scheduled to conclude at the beginning of 2009. It is planned that the plant will become fully operational after 3 months when it reaches the designed production capacity.

The main assets of the facility after the completion of the investment project will include:

• Diversified product portfolio (at the meeting point of two sectors),

• Lowest costs of production in the charcoal sector (revenues from the sale of energy),

• Advantageous, in terms of logistics, localization (at the junction of three Regional Directorates of State Forest, relatively close to the German border, as well as close to several hundred plants that can provide raw material, i.e. waste timber).

 
Technology:
Timber of deciduous trees processed in two independently operated production lines (continuous retorts) is the main production material. The resulting heat is converted in two high-pressure waste-heat boilers into steam (one boiler in each production line). There is another high-pressure steam boiler installed at the plant, fuelled with biomass (rape straw or wooden chips). After combusting biomass in the boiler, the produced steam is directed to a steam turbine collector. The capacity of the installed turbine, designed and manufactured in SIMENS plant in Bern is 7.23 MW. Additionally, the turbine will be prepared for heat take off and possible distribution of heat to the town heat distribution network in Wałcz. The designed solution ensures much flexibility for the future.
Timber will be supplied for production from current deliveries and from a wood yard located on the premises. Timber stored in the wood yard will secure production for 5 months. Timber is fed to a fragmentation line with a transport system. The transport system conveys timber directly to a cutter. The cut timber is transferred to a drying tank with automatic timber conveying system and hopper. Timber is dried in vertical drying chambers using hot air (heated up by combustion gases from the production process). As a result of heating in the retort, water remaining in timber evaporates. As timber falls, it gets to a decomposition zone, with a temperature of ca. 300° C. In high temperature, steam-gases are produced, containing acetic acid, methanol, acetone, wood tar and non-condensing gases: carbon dioxide, carbon monoxide, methane and hydrocarbons, hydrogen and reaction water. Partially charred timber falls into the annealing zone, where it is finally charred with gasification of a large amount of non-condensing gases. Falling further, timber reaches a cooling zone. Then a transporter conveys the cooled charcoal to a packing station. Weighted portions of charcoal are poured into paper bags and automatically sewed. Packed charcoal, stacked on pallets is directed to a conditioning warehouse. After conditioning, charcoal is stored in the main warehouse and transported by trucks to a distribution center.
In the meantime, flue gases produced as a result of combusting steam-gases generated during the thermal decomposition process are sent directly from the furnace to the high-pressure waste-heat boiler. Flue gases flowing through the boiler produce overheated steam. The steam is fed to a turbine, which drives a power generator that produces electricity for the grid. Steam coming through the turbine gives away heat that is planned to be sent to the town heat distribution network in the future.
Moreover, straw (mainly rape straw) and wooden chips (alternative to straw) are supplied to the plant, and after combustion in the biomass boiler supplement the amount of steam required to produce 7.23 MW of electricity (installed capacity). At the same time, they stabilize the operation of the steam turbine.
In the charcoal production process, as a result of mass shifting and dust extraction in the charcoal packing stations non-commercial fraction is produced (0-20mm granulation). In order to use the waste, the plant produces charcoal briquettes. Introduction of the fine charcoal briquette making technology will optimize the use of heat generated in the biomass fuelled boiler and will increase the production efficiency by selling otherwise unsellable mass of charcoal – the resulting dust. The drawings below present diagrams of the heat and power plant and the continuous retorts.

Co-financing by the European Union:
The project is co-financed with the European Union funds under the Improvement of the Competitiveness of Enterprises Sectoral Operational Program (Action 2, sub-action 2.2.1). The high value of support amounting to PLN 33.3 million results from the high level of innovativeness of the project.