Resource recovery of organic sludge as refuse derived fuel by fry-drying process

• Fry-drying organic sludge was odor free.
• The calorific value of fry-drying organic sludge was higher than RDF standards.
• The organic sludge with fry-drying process could reduce NOx and SOx emission.
• Combustion efficiency of fry-drying organic sludge has a significant increase.

The organic sludge and waste oil were collected from the industries of thin film transistor liquid crystal display and the recycled cooking oil. The mixing ratio of waste cooking oil and organic sludge, fry-drying temperatures, fry-drying time, and the characteristics of the organic sludge pellet grain were investigated. After the fry-drying process, the moisture content of the organic sludge pellet grain was lower than 5% within 25 min and waste cooking oil was absorbed on the dry solid. The fry-drying organic sludge pellet grain was easy to handle and odor free. Additionally, it had a higher calorific value than the derived fuel standards and could be processed into organic sludge derived fuels. Thus, the granulation and fry-drying processes of organic sludge with waste cooking oil not only improves the calorific value of organic sludge and becomes more valuable for energy recovery, but also achieves waste material disposal and cost reduction.