Multi-Case Study on Environmental and Economic Benefits through Co-Burning Refuse-Derived Fuels and Sewage Sludge in Cement Industry

Abstract

The use of waste as an energy source in cement clinker production is a promising way to transition toward a circular economy and limit carbon dioxide (CO2) in the atmosphere. The cement industry is responsible for around 5% of global CO2 emissions. In this paper, the analysis of environmental and economic profits associated with the substitution of coal by two refuse-derived fuels (RDF) and sewage sludge (SS) in a cement kiln was presented. Differences in the fuel-related CO2 emissions were calculated for two-, three-, and four-component fuel blends based on the fuel consumption data, heating values, and the correspondent emission factors. The biogenic fraction content of 19% and 43% were measured in RDFs. The material balance of fuels with the assumed technological parameters of the cement clinker production installation (capacity of 6000 Mg per day and unit heat of 3.6 GJ) shows that the RDF heat substitution at the level of 90% allows for a saving of approximately 28.6 Mg per hour of coal, and to manage even approx. 40 Mg per hour of RDF. The increase in the share of SS in the total heat consumption to 6% contributed to reducing the actual emissions by 17 kg of CO2 per 1 Mg of clinker. Multilateral benefits due to the use of RDF in the cement plant were evident.

Recent Advances on the Uses of Biomass Alternative Fuels in Cement Manufacturing Process: A Review

“…Research indicates that the traditional process of cement production emits approximately 0.7 to 0.9 tonnes of CO 2 per tonne of clinker produced. 72 The IEA in its Cement Industry Technology Roadmap, has set forth long-term objectives for reducing CO 2 emissions: by 2050, the aim is to lower CO 2 emissions to about 0.5 tonnes or less per tonne of clinker. 23 This transformation is projected to result in a noteworthy decrease in the CO 2 intensity of the global cement thermal energy demand from 0.088 tonne of carbon dioxide per gigajoule (tCO 2 /GJ) to 0.058 tCO 2 /GJ over that period.…”

“…According to forecasts from ECA and IEA, by 2050, the proportion of alternative fuels in the European cement industry will reach 90%, while globally the proportion of alternative fuels in the cement industry will reach 30%. , This increase will effectively contribute to reducing the CO 2 emissions generated during the production of each tonne of cement clinker. Research indicates that the traditional process of cement production emits approximately 0.7 to 0.9 tonnes of CO 2 per tonne of clinker produced . The IEA in its Cement Industry Technology Roadmap, has set forth long-term objectives for reducing CO 2 emissions: by 2050, the aim is to lower CO 2 emissions to about 0.5 tonnes or less per tonne of clinker .…”