ENERGY RECOVERY FROM LEATHER WASTES BY GASIFICATION

Clean technologies imply collecting and eliminating all wastes. The leather processing industry and derived leather manufacturing industries generate a large and diverse amount of waste which needs to be recovered. Protein waste disposal by combustion seems at first interesting and represents an important source of energy, as leather has half the calorific value of diesel oil. In practical terms, the solution of burning waste is difficult to apply as the smoke generated becomes a polluting source for the environment. Gasification is a much more demanding primary technology than direct combustion. To be used in the gasification process, waste must meet a number of conditions such as: low humidity, below 30%; granulation as homogenous as possible and ranging between 0 and 30mm; good tensile strength; free of chlorine, sulfur, arsenic content etc. To streamline the process is useful an auxiliary heat source to provide heat for the first two exothermic reactions of the process. To minimize the tar content must be cracked areas with temperatures 1000 degrees C-1200 degrees C. The paper presents the proposed process and plant for gasification of leather waste mixed with hardwood biomass and turning it into a compact and rigid charcoal allowing the passing of resulting gas through its layer. The paper also presents characteristics of resulting gases, methods of purification, and solutions for their exploitation while recovering heat for the tannery's own needs or for other applications.