SZL series biomass-fired hot water boiler
SZL series biomass-fired hot water boiler is package or shop-assembled water pipe boiler with double steam drum and chain grate stoker structure. 4-6 tph boiler is package boiler and 6-35 tph is shop-assembled structure, which is composed of 2 parts, upper part is heat absorbing surface and lower part is combustion equipment. The former part of boiler body is surrounded by membrane wall, its upper part connects with boiler drum and lower part connects with header, which forms a combustion chamber to absorb the radiated heat from furnace; there are dense convection tube bundle between the back side of upper and lower drum, the high temperature smoke enters a separate economizer after flushing heat absorbing surface then discharge from chimney.
Product thermal capacity : 2.8-29 MW
Working pressure : 1.0-1.25 MPA
CNC manufacturing technology
The key processing technologies such as steel plate blanking, circling, drum and tube plate drilling adopt advanced CNC machining to reduce the assembly stress and prolong the service life of the boiler.
Steel tube cutting, thread tube pressing and convection tube processing all adopt advanced CNC technology.
Arched tube sheets and threaded fire tube was first adopted in China to increase heat transfer and completely solve the problem of cracking of the back tube sheet.
Chain grate plate and back smoke chamber plate is cut by CNC plasma cutting machine, which looks neat and beautiful.
Advanced welding process
The vertical and circumferential seam welding of the boiler adopts advanced automatic submerged arc welding technology to ensure the welding quality. All vertical and circumferential welds will go through 100% ray detection.
The welding of smoke tube and the tube plate adopts pre-expansion to eliminate the gap between the tube and tube plate, then be welded by automatic argon arc welding, which effectively eliminate stress and prolong boiler life.
The flange of the socket is welded by robots.
The chain grate is manufactured by our factory, and it is tested for 72 hours before leaving the factory to ensure that the tightness is moderate and won’t deviate.
Low NOx emissions
Graded air supply and special furnace arch structure decrease the NOx emissions to 100mg/m³.
Different biomass raw materials are analyzed by numerical simulations, thermal efficiency is more than 90%.
Unique structural design
According to different capacity, different numbers of independent air bins are arranged from front to back of the grate.
The user can reasonably adjust the air distribution according to different combustion conditions to ensure that the fuel is fully burnt.
Secondary air is input to disturb fuel gas in the furnace, to ensure the fuel is burnt totally. The independent secondary fan makes it easy to control and adjust the air volume and air pressure.
Feeds evenly feeding and avoid flashback.
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