Bioflamm® traversal grate furnace
Series: TR-B
Use: Sawmills, local heating plants, contractors and furniture manufacturing plants
Power range: 250 to 6,000 kW
Fuels: Wood chips, timber materials
Max. water content: 60%
In many areas of the wood-processing industry, production debris accrues in the most diverse forms, such as sawdust, shavings, wood pieces and chips. The palette of fuels with respect to bulk density and water content is very diverse. Along with the wood-processing operations, wood as a source of energy is attracting more and more attention in the heating market in general. Politically oriented funding programs support the environmentally friendly production of heat. The development of oil prices affects everyone, whether they are communities, energy supply companies, agriculture or gardening operations. The demand for adequate furnace systems is stronger today than ever before. Even if the wish for the ultimate, versatile solution is often heard, there is no ideal furnace for all fuels. We take this fact
into consideration in particular, since we have developed a broad range of furnace systems for the market on the basis of the stoker-fired furnace.
The Task:
Damp and ash-rich fuels are available in sawmills and community wood heating plants in particular. The use of particle and MDF boards in the furniture industry likewise brings high ash content as well as a tendency of slag buildup. These materials require particular attention during the construction of an adequate furnace.
The Basis
Based on the patented system of the Bioflamm ® degassing furnace, the step grate external furnaces were advanced in light of the grate geometry. The following aspects were particular priorities in this process:
· optimal heating efficacy
· fast adjustability pursuant to DIN 4751 Part2
· prevention of the buildup of slag pieces
· complete combustion
· low radiation loss - modular design
· flexible applications
· ability to combine with the available Bioflamm® boiler program
The Solution:
In order to achieve optimal stoking with respect to fuel characteristics, the arrangement of the grates is horizontal. Through constant circulation, the traversal grate achieves pre-drying as well as a high retention
time. The movement of the fuel bed prevents the buildup of slag pieces. With the addition of primary air, the material located on the grate is degassed and is combusted completely in the flame pipes in the transfer to the combustion chamber of the boiler through targeted secondary air intake. The grates comprised of heat-proof specialty cast material have a hydraulic drive. For individual concerns, special designs of the grate bars are available. All relevant positions of the furnace are easily accessible through inspection ports. The proven separation of furnace and boiler enables fast adjustability pursuant to DIN
4751 Part 2 in the traverse-grate furnaces also. The grate maintains an adequate fuel bed even if the shut down occurs over multiple hours. The furnaces are supplied in two models, TR-B.. -N and TR-B..-T for wet as well as dry fuels. The grate surfaces are designed on a connective heating value.
The Optimum:
The application in the wood industry, with presses, dry and wet chambers or as a baseload boiler in a wood heating plant requires a long service time for the furnace during heavy use.
For this reason, the Bioflamm® traverse grate furnaces have in general a cooling screen, which is integrated into the fireclay lining. In this way, radiation loss is minimized and fireclay service times are increased.
The cooling pipe system is produced according to TÜV guidelines and is operated in connection with the boiler circulation or separately as well. Furthermore, the watercooled de-ashing screw meets all requirements for the reliable transport of the combustion chamber ashes into the connected ash container.
The Options:
As a standard, all traverse grate furnaces have connection options for flue gas recirculation. This can be retrofitted at any time. Thus, a further reduction in the NOx values is possible for particle and MDF boards. On request, all furnaces can be supplied with a SPS furnace optimization (Bioflamm® Optimatic). The regulation of the combustion air intake as well as the negative pressure then occurs automatically, depending on the external furnace and combustion chamber temperatures and the residual oxygen content. In the highest equipment level, the combination with remote-data transfer and process
visualization is also an option. Support from the WVT customer service is now faster and more problem-oriented. For the application of large wood chips, a hydraulic piston drawer can be supplied in
place of the series-standard combustion screw conveyor. The maintenance of the external furnace principle furthermore enables the combination with steam and thermal oil boilers.
Conclusion:
The standards for modern boiler systems are always:
- high performance
- optimal efficacy
- and, in particular, the maintenance of the relevant emissions standards.
For this reason, it is inevitable that, in the conception of the boiler system, the right furnace for the available fuel characteristics must be applied. This requires well-founded theoretical knowledge, comprehensive experience and constant development. We have brought over 40 years of knowhow to the development of the traverse grate furnace. As our customer, you will benefit from this.
