Hydrothermal Carbonization of Organic Components from Municipal Solid Waste

The hydrothermal carbonization of organic ingredients from municipal solid waste (exemplified by apples, meat, offset paper, newsprint, birch and oak sawdust, cotton cloth, polypropylene, and polyethylene terephthalate) is studied in the temperature range 240–280°C. The yield of the solid hydrothermal carbonization product (excluding plastics) is 0.50–0.62 at 240°C, 0.46–0.54 at 260°C, and 0.37–0.46 at 280°C. The yield of the solid product in the case of polypropylene and polyethylene terephthalate is close to 1. When increasing the temperature, the carbon content of the solid product increases from 45–52% for the initial ingredients to 61–75% for the products obtained at 280°C (excluding plastics). The calorific value of the products of hydrothermal carbonization obtained from organic waste with a calorific value of 15 to 19 MJ/kg (excluding plastics) is 19–26 MJ/kg for 240°C and 21–29 MJ/kg for 280°C. The products of the hydrothermal treatment of apples and sawdust at 280°C have the highest calorific values (28–29 MJ/kg). The calorific value of plastics after hydrothermal treatment remains practically unchanged.