Dynagrate Combustion Grate Launched by Babcock and Wilcox Volund

The new water-cooled DynaGrate with integrated cooling system in the axle. 5 December 2010 Babcock & Wilcox Vølund has launched its latest state-of-the art combustion grate, the DynaGrate, is which it claims to be one of the most advanced combustion grates on the Waste to Energy market. According to Babcock and Wilcox, DynaGrate is distinguished by its suitability for both high and low calorific fuel and is capable of handling all sorts of unsorted waste. Furthermore, DynaGrate offers the possibility of biomass co-firing. The system resembles a staircase. The individual steps – the grate bars – are alternately placed horizontally and vertically. These grate bars are mounted on shafts and, as the grate bars of one shaft interfere with the bars of the adjoining shaft, a continuous grate carpet is formed. When the shafts turn 60 degrees in the opposite direction during the movement of the grate, the steps are changing from vertical to horizontal and from horizontal to vertical. The changing of the steps produces a waving longitudinal optimum turnover and distribution which ensures the drying, conveying and combustion of the waste bed. This gives a very strong agitation of the fuel bed resulting in excellent burnout of the waste. Typically, the loss of ignition in the bottom ash measured as TOC is around 1/4 %. One of the new unique developments is the integrated water cooling system. The cooling water is led to and from the grate through the shaft ends and to the middle sections of the shafts through firm pipe connections, see figure. There are no sensitive hose connections inside the furnace. Damages due to grate siftings, melting tin, aluminium, etc. are efficiently prevented. The cooling circuit is dimensioned for the maximum possible heat flux from the burning fuel bed. The normal heat transfer lies between 15-20 kW per square meter. During normal operation, the entire transferred energy from the grate can be returned to the combustion process because the energy can be used for heating of the combustion air. The boiler efficiency and electricity production will thus be maintained when using a water-cooled grate. The company say that the development of DynaGrate is based on 40 years of continuous experience of the renowned BS technology. DynaGrate is renowned for: Its unique movement: A strong agitation of the fuel bed results in an excellent burn out of the waste fuel. Its unique design: There is no contact between the grate bars. This design ensures minimum impact of mechanical forces and minimizes the wear and thereby the need for spare parts. Its unique cooling system: A fully integrated water cooling system ensures a stable operation and minimal corrosion due to low grate surface temperature. Its unique size: The grate modules can be combined to grates of various lengths and widths. The largest width of one grate line is 6 meters. Larger grate widths can be achieved by placing several lines side-by-side. Therefore DynaGrate® has a capacity range of 4-44 t/h. Read more about the many other advantages of the unique DynaGrate