Product Overview
The SZL Series Biomass/Coal-Fired Water-Tube Steam Boiler is designed for continuous, high-capacity industrial steam supply using coal and selected biomass fuels. Its longitudinal double-drum construction combines membrane water walls, a mechanized chain grate, zoned under-grate airflow, and secondary air injection for stable combustion and efficient heat transfer. An S-shaped convection flue-gas path promotes coarse ash separation, while optimized natural water circulation supports reliable steam quality under changing loads. Factory-preassembled sections simplify transportation and on-site installation for demanding industrial applications.
Product Structure Drawing
Key Advantages
The 4 t/h model can be delivered as a packaged unit, while 6–35 t/h models use preassembled upper-boiler and lower-grate sections to reduce site assembly and installation time.
Longitudinal double drums and membrane water walls form the furnace enclosure and front/rear arches, improving sealing, radiant heat absorption, and structural durability while reducing refractory maintenance.
A mechanized chain grate with up to six under-grate air chambers allows staged airflow adjustment for fuel drying, ignition, combustion, and burnout, promoting more uniform firing.
An S-shaped convection flue-gas path helps separate coarse fly ash into four gravity ash hoppers, reducing particulate loading on downstream dust-collection equipment.
Balanced downcomers and risers, combined with ample steam-water capacity, support stable circulation, steam quality, and flexible load response. Any 110% overload rating requires model-specific confirmation.
A high-positioned biomass feed inlet and adjustable front-wall secondary-air injection improve the mixing and burnout of combustible volatiles, supporting efficient operation across suitable biomass fuels.
Typical Applications
Pulp processing, paper drying, and continuous plant steam
Veneer drying, wood conditioning, and hot-press heating
Cooking, grain processing, feed conditioning, and utility steam
Dyeing, washing, fabric finishing, and drying
Reactor heating, batch processing, and process steam
Central steam supply; hot-water service on dedicated variants
Technical Specifications
| Item | model | SZL2–1.25–All SZL2–1.6–All SZL2–2.5–All SZL1.4– 0.7/95/70–All fast assembly | SZL4–1.25–All SZL4–1.6–All SZL4–2.5–All SZL2.8– 0.7/95/70–All fast assembly | SZL6–1.25–All SZL6–1.6–All SZL6–2.5–All SZL4.2– 1.0/95/70–All packaging assembly | SZL8–1.25–All SZL8–1.6–All SZL8–2.5–All SZL5.6– 1.0/95/70–All packaging assembly | SZL10–1.25–All SZL10–1.6–All SZL10–2.5–All SZL7– 1.0/95/70–All packaging assembly | SZL15–1.25–All SZL15–1.6–All SZL15–2.5–All SZL10.5– 1.0/115/70–All packaging assembly | SZL20–1.25–All SZL20–1.6–All SZL20–2.5–All SZL14– 1.0/115/70–All packaging assembly |
| Rated evaporation capacity(t/h) Rated supply heat capacity(MW) | 2/1.4 | 4/2.8 | 6/4.2 | 8/5.6 | 10/7 | 15/10.5 | 20/14 | |
| Working pressure(MPa) | 1.25/1.6/2.5/0.7 | 1.25/1.6/2.5/0.7 | 1.25/1.6/2.5/1.0 | 1.25/1.6/2.5/1.0 | 1.25/1.6/2.5/1.0 | 1.25/1.6/2.5/1.0 | 1.25/1.6/2.5/1.0 | |
| Rated steam temperature outlet temperature(°C ) | 194/204/226/95 | 194/204/226/95 | 194/204/226/95 | 194/204/226/95 | 194/204/226/95 | 194/204/226/115 | 194/204/226/115 | |
| Feed water temperature Return water temperature(°C ) | 20/70 | 20/70 | 20/70 | 20/70 | 20/70 | 20/70 | 20/70 | |
| Heating area( m² ) | Body | 70 | 100 | 142 | 215 | 234 | 318.5 | 504 ( steam ) 396 ( water ) |
| Economizer | 35 | 66 | 130 | 130 | 174 | 348.8 ( steam ) 174 ( water ) | 377.6 ( steam ) 236 ( water ) | |
| Effective area of grate ( m² ) | 3.22 | 6.72 | 7.52 | 10.25 | 11.8 | 18 | 23.2 | |
| Fuel type | Q ≈ 21000KJ/Kg II class bituminous coal, low leave heat value Q ≈ 21000KJ/Kg | |||||||
| Fuel consumption ( kg/h) | ~ 300 | ~ 590 | ~ 880 | ~ 1160 | ~ 1450 | ~ 2200 | ~ 1160 | |
| Exhaust flue gas temperature(°C ) | 135 ~ 145 | |||||||
| Thermal efficiency ( % ) | 84 ~ 85 | |||||||
| Weight of biggest part for transportation ( t ) | 25 | 30 | 22.5 | 25 | 28 | 30 | 35 | |
| Overall dimension part for transportation L × W × H ( mm ) | up 5500×2350×3650 | up 7730×2360×3520 | up 6150×2840×3540 down 7275×2852×2580 | up 6971×2933×3540 down 8056×2945×2580 | up 7855×3240×3540 down 9025×3200×2580 | up up10000×3240×3540 down 12000×3200×3080 | up 11000×3240×3540 down 14000×3200×3080 | |
