Treatment and use of landscape conservation and maintenance work – innovations and trends at the trade fairs LIGNA and Elmia Wood
Despite low fuel oil and gas prices and more stringent emission requirements, the use of wood as fuel was once again a focus of the world’s largest forestry and timber trade fairs LIGNA and Elmia Wood. The project greenGain was represented at the LIGNA fair which took place from 22 until 26 May 2017 in Hannover with an information stand.
During both events, the importance that the energetic utilisation of wood has by now was reflected. Using available raw materials efficiently and in an environmentally friendly way has been the guiding theme of the LIGNA in Hanover for several years. This year, the latest trends, developments and solutions for firewood harvesting, treatment and energy use were again presented in the technology line From Tree to Fuel organized by the Chamber of Agriculture Lower Saxony (COALS). The clear focus of the technical developments and procedures is the compliance of the stricter emission limit values of the German Federal Pollution Control Ordinance (1.BImSchV). In addition, possibilities for the treatment of wood chips were presented, which particularly concerns material from landscape conservation and maintenance work (LCMW). Thus, in addition to chippers, screening machines and dryers were shown as well.
Also in Scandinavia, fuel wood is still a major issue as seen on the fair Elmia Wood in Jönköping in Sweden. Here, chippers were presented in practice (Photo 1) in addition to the various and well-known techniques for firewood preparation such as saws, splitters and processors. In Sweden, besides LCMW material, weak wood is collected from the wood harvest and used as fuel. Thus, mostly disc- or drum chippers, ranging from attachments for tractors to trailer superstructures, were shown and presented (Photo 2).
Environmentally friendly firings
The quality of the fuel in addition to boiler and filter technology plays a decisive role in the endeavour to heat in an environmentally friendly manner and to comply with the legal limits. The “Deutsche Pelletinstitut GmbH” (DEPI, German Pellet Institute Ltd.) presented the ENplus quality mark for wood chips in Hanover (photo 3). The aim here is to provide a fuel with homogeneous properties which complies with the strict legal requirements for air pollution control. For that, the wood chips are classified according to size, ash content, water content, calorific value, etc. in three quality classes: A1, A2 and B. Due to a high proportion of bark or fine material, LCMW material is mostly categorised as class B. Through appropriate treatment, especially through sieving, class A2 can also be achieved, whereby a higher price can be obtained. In addition, manufacturers and suppliers can be certified when requirements for quality management and assurance, employee training, complaints management, delivery documentation and dimension-related settlements are demanded and trained. For the customer, this increases the security of obtaining high-quality goods.
Filter systems for wood firings
Schräder, a manufacturer of flue gas cleaning systems, introduced the Filterbox-SZ for larger wood firings, which can be expanded in modular construction (photo 4). An electrostatic filter is combined with a cyclone that draws without blower coarse particles from the flue gases before the e-filter. Each module is designed for a boiler output of 100 kW. At a power of 400 kW, four modules are set side by side. The costs are between 11,000 (100 kW) and 32,500 € (400 kW). The smaller e-filters by the brand Ecotube, for installation in the flue gas stream or as an attachment to the chimney plug for power outputs from 50 to 70 kW, are offered starting at 1,600 €.
Information booth by greenGain at the LIGNA
During the five exhibition days of the LIGNA, COALS informed at a stand about the greenGain project and presented technical innovations in the course of guided tours along the technology line From Tree to Fuel (photo 5 + 6). Two times a day, interested visitors followed the explanations of energy expert Carsten Brüggemann and could ask questions about the topic of energy wood.
Photos and authors: Carsten Brüggemann, Aline Clalüna