Cogeneration, also known as Combined Heat & Power (CHP), is an inherently high-efficiency family of technologies to use fossil or renewable fuels to supply energy locally. Heat, power and cooling energy can be supplied to users ranging from individual homes up to large industrial sites and even areas of cities. The biomass boiler with this type has a good popularity in the world industries.
105t/h bagasse and coal fired boiler for cogeneration
The boiler is of the single pass, panel walled girth support design. The girth support design incorporates a combustion chamber support plane just below the mud drum level from which it expands vertically upwards and downwards. The mud drum is supported directly off the boiler steelwork and the upper combustion chamber thus expands at the same rate as the generating bank. The stoker is supported independently of the pressure part on dedicated columns at ground level. A gas tight enclosure is provided by a combination of mechanical and fabric seals at the interface of the combustion chamber and the grate.
The cane tops and trash in the biomass mixture contain alkali metal oxides, which have a propensity to cause fouling of high temperature heat transfer surfaces, especially the superheater. Consequently, the combustion chamber height was increased compared to conventional bagasse/coal-fired boilers in order to provide adequate residence time in the combustion chamber, which ensured that the gas outlet temperature was low enough to prevent fouling.
A 2m high refractory band was cast onto the combustion chamber panel walls to provide the thermal inertia required to burn biomass with a range of moisture contents. The band extends from
the front of the boiler towards the rear along 2/3 of the sidewall depth. In order to prevent slagging
during coal firing, castable refractory is not installed on the rearwall or rear 1/3 of the sidewall depth.
Secondary air is introduced into the furnace from the rearwall at...