Study of briquetted biomass co-firing mode in power plants

• The biomass co-firing mode is suitable for biomass dispersedly distributed areas.
• High economy and efficiency of biomass pretreatment can be realized.
• The biomass can be used through existing equipments efficiently and cleanly.
• Economic analysis shows that this mode is of good economic sustainability.

A briquetted biomass co-firing mode that is feasible in China and other areas with dispersedly distributed biomass resources was proposed, and the details and characteristics of this mode are discussed. Raw biomass from sources such as corn stalks, twigs, and straws was crushed in farmlands and then transported to briquetting stations. The crushed biomass was dried and compressed into briquettes until the moisture content was less than 25%. Finally, the biomass briquettes was stored and delivered to plants like coals for combustion. One of the six layers of the pulverizing system in a 300 MW power plant could be used, and 100% biomass briquettes could be ground by an existing MPS medium speed pulverizer. The biomass briquettes could then be delivered directly into the furnace by primary air. No additional equipment investments were needed for the plant because almost all equipments were already available. Advantages such as cost-effective on biomass collection and transportation, high efficiency and low cost on biomass preprocessing, biomass briquette economic grinding and feeding, and efficient and clean combustion could be realized by this method. The economic sustainability of this mode was also analyzed.