Coal powder briquette machine is a professional equipment that presses coal powder (lignite, bituminous coal, anthracite, etc.) into pellets or blocks under high pressure, which improves combustion efficiency, reduces transportation losses, and facilitates storage and environmental protection.

Equipment type and working principle

Double roller briquette machine (double roller forming machine)

• Principle: Through two synchronously rotating rollers, the coal powder is pressed into spherical, oblate or pillow-shaped particles under high pressure.
• Applicable scenarios: small and medium-sized production capacity (1-10 tons/hour), suitable for civilian briquette, industrial boiler fuel, etc.
• Advantages: compact structure, low energy consumption, and continuous production.

Hydraulic briquette machine

• Principle: The hydraulic system provides ultra-high pressure (50-150MPa) to press high-density coal balls, which is suitable for coal powder with poor adhesion.
• Applicable scenarios: metallurgical industry (coking plant), chemical gasification and other fields with high requirements for strength and calorific value.
• Advantages: high molding density and not easy to break.

Screw extruder

• Principle: Mix coal powder and binder through a screw propeller and extrude into strips, then cut and shape.
• Applicable scenarios: Products that require specific shapes such as honeycomb coal and barbecue charcoal.

Key process parameters

Raw material requirements

• Particle size: 80-200 mesh fine powder, uniformity affects molding strength.
• Moisture: Usually 8-15% is required (too high is easy to stick to the mold, too low requires adding binder).

Binder selection

• Inorganic: bentonite, cement (low cost, but increase ash content and reduce calorific value).
• Organic: starch, lignin (environmentally friendly, but poor high temperature resistance).
• Composite: sodium humate + tar (taking into account both strength and combustion performance).

Molding pressure

• Low pressure molding: 10-30MPa (civilian briquette).
• High pressure molding: 50-150MPa (industrial gasification, coal briquettes for metallurgy).

Key points for equipment selection

• Capacity requirements: select according to the purpose (small 1-5 tons/hour, medium 5-20 tons/hour, large 20 tons or more).
• Molding strength: Industrial briquettes need to have a compressive strength of ≥8MPa, and civilian briquettes can be appropriately reduced.
• Wear-resistant design: The rollers and molds need to be coated with high chromium alloy or tungsten carbide to extend their service life.
• Automation control: The PLC system adjusts the pressure, speed and feed rate to ensure stability.

Common problems and solutions

• Insufficient briquettes strength
• Reason: Insufficient pressure, improper water or binder ratio.
• Countermeasures: Increase the hydraulic pressure to more than 60MPa and adjust the binder addition to 3-5%.
• Equipment blocking or mold sticking
• Reason: The humidity of the coal powder is too high or the viscosity of the binder is too strong.
• Countermeasures: Control the moisture content of the raw materials to ≤12%, and spray a release agent (such as silicone oil) on the mold surface.
• The roller wears too fast
• Countermeasures: Use high-hardness materials (such as 65Mn steel) and regularly clean the coal slag on the roller surface.