IMG_1528Torrefied wood pellets are an immediate and practical replacement for coal. Created through a process called torrefaction, torrefied pellets easily integrate into existing coal power plants, enabling plants to generate clean energy without a lengthy or expensive conversion.

Torrefaction is the process of roasting wood or other biomass material at high temperatures in an oxygen-deprived environment. This process removes and recycles low quality energy from the material and changes its chemical composition. The torrefied wood is then ground and processed through a pellet mill to create durable torrefied pellets. Solvay Biomass Energy’s process for roasting the wood is a trade secret process that has been refined over thousands of hours of testing and production. Torrefied wood pellets have an energy content of 20-23 GJ per metric ton.

 

Grinds & Burns like coal

Torrefied material grinds like coal and can be easily integrated into current coal grinding processes. It also burns similarly to coal so it can be co-fired with coal in any percentage or replace coal completely. By comparison, wood pellets are difficult to grind, limiting their co-firing use to small percentages or requiring the addition of specially designed grinding and handling systems.

Lower Shipping Costs

Torrefied wood pellets have a higher energy density than regular wood pellets, making them more economical to ship than wood pellets with similar total energy content. Torrefied wood pellets are also more moisture resistant and less likely to degrade than wood pellets, making them easier to handle and more practical to ship and store.

Lower sulfur and low ash

The sulfur content of torrefied wood is significantly less than that of coal. Torrefied wood also has substantially less ash content than coal, producing less ash byproduct when burned.

Operates near capacity

Coal plants are often constrained by the volume of fuel that can cycle through various components of the plant.  Torrefied wood pellets have a higher energy density than regular wood pellets, allowing coal plants to operate closer to their rated capacity.

Meets base-load power needs

Other renewable energy sources such as wind and solar cannot produce power on a consistent, predictable basis, so they cannot be relied upon to meet base-load power needs. Torrefied pellets can be used by utilities to meet their base-load power requirements, making them one of the few forms of renewable energy that can replace coal as a source of base-load power.

Economical and available

About 40% of the world’s electricity is generated by coal power plants. These plants represent a large capital investment and, in most instances, it is not economically practical to retire them in the pursuit of cleaner energy. Torrefied wood allows these legacy coal plants to continue supplying power in a much cleaner way, using a renewable, sustainable resource.

Qualifies for renewable energy subsidies

Torrefied wood pellets are a carbon neutral resource and qualify for renewable energy subsidies in many countries.

Proven Results

Our customers are extremely pleased with the ease of integration with existing coal-fired systems. The torrefied pellets run through the mills at significantly greater quantities than wood pellets, without any modification to the systems. In the boilers, there is no change in performance compared to coal operations; the torrefied pellets burn very well.
Several power plants in Europe processed our torrefied pellets through their ball mills without any decrease in the net energy throughput per hour. A coal power plant ran a co-firing test of 70% of our torrefied pellets with 30% coal. The plant ran at 93% of plant capacity with no fouling, which is especially significant as the same plant fouled with only a 10% co-firing of wood pellets.