Biomass briquettes and pellets are both solid fuel products made from agricultural and forestry waste (such as straw, wood chips, rice husks, etc.) through processing. However, they differ significantly in terms of their physical form, processing techniques, and application scenarios. The details are as follows:

1. Physical form and specifications

Biomass briquettes

They are usually in block form, mostly in rectangular or cylindrical shapes, with larger dimensions: the length is generally between 5-30 centimeters, and the diameter or cross-sectional edge length is mostly 3-10 centimeters. The density is relatively low (about 0.8-1.2 tons per cubic meter), and the texture is loose, making them easy to break.

For example: Commonly seen straw briquettes are mostly in a long strip shape, with a length of about 10-20 centimeters, and have a certain elasticity when held in hand.

Biomass pellets

They are in fine cylindrical particles, with uniform size: the diameter is usually 6-12 millimeters, and the length is about 5-30 millimeters. The density is higher (about 1.1-1.4 tons per cubic meter), and the texture is hard, with strong resistance to breakage.

For example: The diameter of wood chip pellets is mostly 8 millimeters, similar to "large cat food", with a firm hand feel.

2. Processing techniques

Comparison item  Biomass briquettes  Biomass pellets

Raw material grinding degree:

The raw materials are ground relatively coarsely (particle size 5-20 millimeters), no need for excessive refinement

The raw materials need to be ground to a finer degree (particle size 1-3 millimeters), with more finely fragmented fiber structure

Forming pressure:

The pressure is lower (usually 50-150 megapascals), relying on the fiber adhesion of the raw materials themselves

The pressure is higher (usually 150-300 megapascals), and some may need to add a small amount of adhesives

Processing temperature:

Mostly at normal or low temperature pressing, without a significant thermoplastic process

During pressing, due to friction, a high temperature (80-180°C) is generated, and the fibers soften, making it easier to form

Equipment characteristics:

The equipment structure is simpler, and the output is larger (single machine production capacity of 1-5 tons)

The equipment precision requirements are higher, and the output is relatively lower (single machine production capacity of 0.5-2 tons)

3. Burning characteristics differences

Burning speed:

Briquettes have a lower density and more pores, burning faster, with a relatively vigorous flame;

Pellets have a higher density and a more compact structure, burning more slowly and persistently, with a stable flame.

Heat value:

Due to the density difference, pellet fuel has a slightly higher heat value (about 4000-4500 calories per kilogram),

Briquettes have a slightly lower heat value (about 3500-4200 calories per kilogram)

but both are higher than the original biomass (such as straw about 3000 calories per kilogram).

Ash content:

Briquettes retain more impurities (such as soil, the surface of straw) due to the coarser grinding of the raw materials, and the ash content is slightly more than pellets;

Pellets have purer raw materials, with less ash content and easier cleaning.

4. Application scenarios

Biomass briquettes

Suitable for large-scale, open-type combustion equipment, such as industrial boilers, biomass hot air furnaces, rural heating stoves, etc. Due to their larger size and convenient feeding, and lower requirements for fuel uniformity. In addition, briquettes have a lower cost and are suitable for scenarios where price sensitivity is high (such as large-scale heating, agricultural drying).

Biomass pellets

Suitable for small-scale, precise combustion equipment, such as home fireplaces, small steam generators, biomass generators, etc. Due to their uniform particles and stable combustion, they can be precisely controlled in dosage through an automated feeding system. At the same time, pellets have a high heat value and low pollution, making them more suitable for scenarios with high requirements for environmental protection and combustion efficiency (such as European household heating, small industrial power).

5. Transportation and storage differences

Transport cost:

Pellets have a higher density, and the same volume weighs more, resulting in lower unit transportation cost; briquettes have a large volume and low density, making long-distance transportation more expensive.

Storage requirements: Pellets have strong water absorption, requiring sealed storage to prevent moisture and caking; The briquettes of fuel have good air permeability and require a slightly lower level of moisture protection during storage. However, they must be avoided from being crushed under pressure. 

The core differences between the two lie in their form specifications, processing accuracy and application scenarios: briquette fuel tends to be "coarse, low-cost, and large-scale usage", while pellet fuel tends to be "fine, high-efficiency, and suitable for small-scale applications". When making a choice, it is necessary to consider comprehensively based on the type of combustion equipment, usage scale and cost budget.