SZL type boiler is a double drum longitudinally-arranged water pipe chain boiler, the fuel falls into the front end of the grate from the front coal hopper, and then falls into the slag discharge machine after combustion. Horizontal biomass boiler performance has superior. The air from the fan enters the grate air chamber through the air duct on both sides of the grate base, and enters the furnace through the fuel layer. The flue gas after fuel combustion passes through the furnace, the embers chamber, the convection tube bundle Ⅰ, the convection tube bundle and the economizer after the boiler, and through the dust collector, and the induced draft fan is pumped to the chimney to discharge into the atmosphere.
Radiant heating surfaces are arranged on the front wall and both sides of the furnace of this series of boilers. The water wall of the front wall is composed of 15 φ51×3 rising pipes drawn from the front collecting box. The water wall of the side wall is composed of 100 φ51×3 rising pipes drawn from the collecting boxes on both sides. This series of biomass fired boiler front arch and left and right side walls are arranged under the secondary air pipe, the secondary air in the middle of the furnace into all directions of the circle. There are two groups of convection tube bundles Ⅰ and a section between the upper and lower drum. The pipe size is φ51×3, and the material is seamless steel tube for No. 20 boiler. The tube bundles are arranged in tandem, with transverse pitch S1=120mm and longitudinal pitch S2=85mm. A cast iron economizer is arranged in the boiler, which can further reduce the boiler exhaust temperature. The flue gas temperature at the outlet of the economizer is lower than 170℃, and the pipe length of the economizer is 1500mm.
The boiler is made of two parts, which are easy to install and move. After the boiler is delivered to the site, it only needs to combine the two major parts, lay the upper and lower furnace walls, install the auxiliary machine systems such as slag discharger, fan and smoke duct, and connect the water and electricity to run. It is convenient to install and has a short period. Horizontal biomass boiler performance is superior, water wall tube arrangement is close, effectively reduce the temperature of both sides of the furnace wall. Therefore, the furnace wall behind the water cooling wall on both sides can be light furnace wall, which can effectively reduce the transportation weight, and has the characteristics of fast start and fire raising.
The boiler products in 70%-100% working conditions can be stable operation, in the case of 100% rated load boiler operating parameters: feed water temperature of 20℃, boiler rated pressure of 1.25MPa, 10 tons of steam produced temperature of 193℃, calculated thermal efficiency of 81.22%, exhaust temperature of 155℃. The fuel consumption was calculated to be 2267.4kg /h biomass pellet fuel (all indicators of the fuel should conform to the relevant provisions of the instruction manual).
Horizontal biomass boiler performance is safe and reliable, combustion equipment (grate) using both sides of the uniform duct pressure subcompartment ventilation structure, segment air supply and other technologies. The grate adopts a new type of large non-coal leakage furnace grate (the original grate is a sheet type grate), which makes the operation of the boiler portable and reliable, the heating grate is basically not subject to tension, not easy to damage; The boiler running coal leakage is less than the sheet grate, can save 1-2% coal; And the ventilation conditions are good, there is a certain self-cleaning ability.