Increased energy cogeneration in the sugar-energy sector with the use of sugarcane straw, electrification of drives, and high-drainage rollers in the extraction

Abstract

The sugar-energy sector stands out in the production of electrical energy in the Brazilian energy matrix. The updating of Law 9,427 allowed increasing the limit of power injected in the transmission or distribution systems of existing projects from 30 to 50 MW, encouraging studies of expansion and/or implementation of new cogeneration projects. This study analyzed technologies to enhance energy cogeneration in a plant that sells about 27 MW of surplus power. For this, were studied the use of straw, electrification of drives by steam turbines, and high-drainage rollers (lotus mill roller), which allows reducing bagasse moisture, increasing its lower calorific value (LCV) and, consequently, electrical energy generation. Mass and energy balances in the energy plants of the proposed cases were performed using the software IPSEpro®. Economic analyses were carried out using the conventional techniques of economic engineering (payback period, net present value-NPV, internal rate of return-IRR, and return on invested capital-ROIC). These analyses allowed the technical and economical identification of cases with viability, according to the value of the electrical energy sold.