How Raw Material Moisture Affects the Economics of Briquetting

In wood briquette production, raw material moisture is one of the key technological parameters that directly determines pressing stability, finished product quality, and the overall economics of the production process.

Even minor deviations from the optimal moisture range can alter the operating conditions of the equipment and increase operating costs.

Where Is the Threshold for a Stable Process?

To produce high-quality briquettes, the raw material moisture content should be:

• 8–12% — the optimal range for stable pressing and high-quality briquette formation;
• 12–15% — a risk zone where producing quality briquettes becomes more difficult;
• Above 15% — a high risk of damage to press components.

Once the moisture content exceeds 12%, the process begins to move away from its optimal operating conditions. Above 15%, not only does product quality deteriorate, but there is also a significant risk of mechanical damage to the press.

Risk of Insufficient Moisture <8%

When the moisture content falls below the lower limit of 8%, the material lacks the necessary conditions for lignin plasticization. Without this activated natural binder, the briquette cannot maintain its shape.

This results in insufficient structural integrity, producing loose and brittle briquettes that are prone to crumbling during handling or transportation.

How Small Deviations Affect Production

Even a 3–5% change in moisture content during production can have significant consequences:

• increase in energy consumption for drying;
• Reduced briquette density and dimensional stability;
• Increase in off-spec production;
• Reduction in production line capacity;
• Higher maintenance and operating costs.

Why Is Moisture Content Unstable?

In practice, moisture variations are usually caused not by the equipment but by the raw material itself:

• Raw material deliveries with moisture levels ranging from 6% to 40%;
• Seasonal variations in wood moisture of up to 10–15%;
• Mixing of different material fractions (wood chips, bark, sawdust);
• Lack of homogenisation and proper pre-processing of the raw material.

This is especially common at facilities processing wood industry residues, where the composition of the incoming raw material changes daily.

How to Stabilise the Process

To ensure stable operation of the production line, the raw material moisture content should be maintained within the recommended technological range:

Target moisture content: 8–12%

This can be achieved by using:

• Pre-drying systems with automatic process control;
• Homogenisation bins to stabilise raw material composition;
• Moisture monitoring at the production line inlet;
• Automatic material feed control.

Raw material moisture is one of the fundamental technological parameters determining the stability of the entire briquetting process. Therefore, accurate moisture control and stabilisation are essential for ensuring safe, reliable, and cost-efficient operation of a briquetting line.

If you are planning to install a new briquetting line or improve the efficiency of an existing production facility, RMP specialists can help you select the optimal technical solution based on your raw material characteristics and production requirements. We provide a comprehensive range of services—from initial process analysis and engineering to equipment supply, commissioning, and after-sales service. A properly designed raw material preparation system ensures consistent briquette quality, reduces operating costs, and helps maximise the return on your investment.