Conventional and Alternative Sources of Thermal Energy in the Production of Cement—An Impact on CO2 Emission

Abstract

The article evaluates the reduction of carbon dioxide emission due to the partial substitution of coal with alternative fuels in clinker manufacture. For this purpose, the calculations were performed for seventy waste-derived samples of alternative fuels with variable calorific value and variable share in the fuel mixture. Based on annual clinker production data of the Polish Cement Association and the laboratory analysis of fuels, it was estimated that the direct net CO2 emissions from fossil fuel combustion alone were 543 Mg of CO2 per hour. By contrast with the full substitution of coal with alternative fuels (including 30% of biomass), the emission ranged from 302 up to 438 Mg of CO2 per hour, depending on fuel properties. A reduction of 70% in the share of fossil fuels resulted in about a 23% decrease in net emissions. It was proved that the increased use of alternative fuels as an additive to the fuel mix is also of economic importance. It was determined that thanks to the combustion of 70% of alternative fuels of calorific value from 15 to 26 MJ/kg, the hourly financial profit gain due to avoided CO2 emission and saved 136 megatons of coal totaled an average of 9718 euros. The results confirmed that the co-incineration of waste in cement kilns can be an effective, long-term way to mitigate carbon emissions and to lower clinker production costs. This paper may constitute a starting point for future research activities and specific case studies in terms of reducing CO2 emissions.

Carbon Footprint Evaluation of Hazardous Waste Based Solid Fuel: Application in a Cement Kiln

“…The CO2-eq emission from a cement manufacturing plant is originated from the decarbonization of the raw materials (CaCO3 → CaO +CO2) and combustion of carbon (C + O2 → CO2) in the fuels used for providing energy for the overall endothermic reactions in the kiln system (Lin, Kiga, Wang, & Nakayama, 2011;Wojtacha-Rychter, Kucharski, & Smolinski, 2021). Hence, the emissions generated from the combustion of IWSF in a cement manufacturing plant were predicted via the stoichiometric method.…”

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

“…The elemental analysis of the RDF samples from several municipal solid waste management plants [41] and a cement plant in Poland [42] showed that the carbon content ranged from 30 to 60% for waste fuels. In comparison, the carbon content in fossil fuels increased to over 90% (for anthracite [43]). Bielowicz et al [44,45] presented the chemical analysis of the share of elements in 28 coal samples including low-rank and bituminous coal samples derived from the Coal Basin in Poland and showed that the carbon content ranged from 63.40% (lignite) to 89.73% (coking coal).…”

“…The assessment of the environmental and economic advantages in terms of the use of RDF and sewage sludge in cement plants was the objective of this paper. The benefits of a cement plant working on coal and partly replacing fossil fuels with an alternative fuel have been presented in many works [43,46,47]. The authors of [43] provided a benefits-based case study where the substitution of 10-90% coal with the alternative fuel was assumed.…”

Possibilities for Reducing CO and TOC Emissions in Thermal Waste Treatment Plants: A Case Study

“…This includes, for example, plants intended to treat food-industry waste [8][9][10][11] and hospital waste [12][13][14]. In some studies, models of the interdependence between combustion-process emission parameters and other important factors, such as 2 of 11 waste-to-energy, were highlighted and presented [15][16][17][18][19][20]. Examples of methods for reducing the emission of harmful compounds are included in the articles [21][22][23].…”