Archive for 8.3.3 Cement and Concrete

Emerging Energy-efficiency and CO2 Emission-reduction Technologies for Cement and Concrete Production

Globally, the cement industry accounts for approximately 5 percent of current anthropogenic carbon dioxide (CO2) emissions. World cement demand and production are increasing significantly, leading to an increase in this industry’s absolute energy use and CO2 emissions. Development of new energy-efficiency and CO2 emission-reduction technologies and their deployment in the market will be key for the cement industry’s mid- and long-term climate change mitigation strategies. This report is an initial effort to compile available information on process description, energy savings, environmental and other benefits, costs, commercialization status, and references for emerging technologies to reduce the cement industry’s energy use and CO2 emissions. Although studies from around the world identify a variety of sector-specific and cross-cutting energy-efficiency technologies for the cement industry that have already been commercialized, information is scarce and/or scattered regarding emerging or advanced energy-efficiency and low-carbon technologies that are not yet commercialized. This report consolidates available information on nineteen emerging technologies for the cement industry, with the goal of providing engineers, researchers, investors, cement companies, policy makers, and other interested parties with easy access to a well-structured database of information on these technologies.

8 Energy Intensive Industries, 8.3 Energy Efficiency Measures in Key Industrial Sectors, 8.3.3 Cement and Concrete

A Review of Emerging Energy-efficiency and CO2 Emission-reduction Technologies for Cement and Concrete Production

Globally, the cement industry accounts for approximately 5 percent of current man-made carbon dioxide (CO2) emissions. Development of new energy-efficiency and CO2 emission-reduction technologies and their deployment in the market will be key for the cement industry’s mid- and long-term climate change mitigation strategies. This paper is an initial effort to compile the available information on process description, energy savings, environmental and other benefits, costs, commercialization status, and references for emerging technologies to reduce the cement industry’s energy use and CO2 emissions. This paper consolidates available information on eighteen emerging technologies for the cement industry, with the goal of providing engineers, researchers, investors, cement companies, policy makers, and other interested parties with easy access to a well-structured database of information on these technologies.

8 Energy Intensive Industries, 8.3 Energy Efficiency Measures in Key Industrial Sectors, 8.3.3 Cement and Concrete, Uncategorized

Potential Energy Savings and CO2 Emissions Reduction of China’s Cement Industry

This study analyzes current energy and carbon dioxide (CO2) emission trends in China’s cement industry as the basis for modeling different levels of cement production and rates of efficiency improvement and carbon reduction in 2011-2030. Three cement output projections are developed based on analyses of historical production and physical and macroeconomic drivers. For each of these three production projections, energy savings and CO2 emission reduction potentials are estimated in a best practice scenario and two continuous improvement scenarios relative to a frozen scenario. The results reveal the potential for cumulative final energy savings of 27.1 to 37.5 exajoules and energy-related direct emission reductions of 3.2 to 4.4 gigatonnes in 2011-2030 under the best practice scenarios. The continuous improvement scenarios produce cumulative final energy savings of 6.0 to 18.9 exajoules and reduce CO2 emissions by 1.0 to 2.4 gigatonnes. This analysis highlights that increasing energy efficiency is the most important policy measure for reducing the cement industry’s energy and emissions intensity, given the current state of the industry and the unlikelihood of significant carbon capture and storage before 2030. In addition, policies to reduce total cement production offer the most direct way of reducing total energy consumption and CO2 emissions.

8 Energy Intensive Industries, 8.3 Energy Efficiency Measures in Key Industrial Sectors, 8.3.3 Cement and Concrete

Policy Options for Encouraging Energy Efficiency Best Practices in Shandong Province’s Cement Industry

The sectoral approach is a mechanism to organize “action by key product producers in a specific industry sector and their host governments to address the greenhouse gas emissions from their products and processes” (WBCSD, 2009). This research analyzes the concept of a sectoral “no-lose” target under which tradable emission reduction units would be issued for emission reductions beyond the agreed sector baseline. However, no penalty would apply in case the country failed to meet the target (therefore called “no-lose” target).The process intends to strengthen government and national ownership over public sector policy and enhance the coherence among policy, spending and results (European Commission, 2007). It is also a recognized mechanism that works in conjunction with other policies and processes as elements of a comprehensive post-2012 climate framework.This research intends to explore possible design options for a sectoral approach in the cement sector in Shandong Province and to consider its respective advantages and disadvantages for future application.

8 Energy Intensive Industries, 8.3 Energy Efficiency Measures in Key Industrial Sectors, 8.3.3 Cement and Concrete

Quantifying the Co-benefits of Energy-Efficiency Programs: A Case Study of the Cement Industry in Shandong Province, China

China’s cement industry produced 1,868 million metric tonnes (Mt) of cement in 2010, accounting for more than half of the world’s total cement production (MIIT 2011). Consistent with the Chinese cement industry’s large production volume, total CO2 emissions from the industry are very high, as are associated air pollutant emissions, including sulfur dioxide (SO2), nitrogen oxides (NOX), carbon monoxide (CO), and particulate matter (PM). These emissions cause significant regional and global environmental problems (Lei et al. 2011). The cement industry is the largest source of PM emissions in China, accounting for 40 percent of PM emissions from all industrial sources and 27 percent of total national PM emissions (Lei et al. 2011). This report studies several collateral health and environmental benefits (co-benefits) of energy-saving measures in the cement industry and shows that including co-benefits can significantly affect the cost effectiveness of some energy-efficiency measures. We use a modified cost of conserved energy (CCE) calculation to determine the monetary value of the co-benefits of reduced damage to human health that results from reduced air pollutant emissions.

8 Energy Intensive Industries, 8.3 Energy Efficiency Measures in Key Industrial Sectors, 8.3.3 Cement and Concrete

Increasing Energy Efficiency and Reducing Emissions from China’s Cement Kilns: Audit Report of Two Cement Plants in Shandong Province, China

The study documented in this report was initiated in order to conduct an energy assessment and to identify the relationship between combustion issues and emissions from cement kilns. A new suspension preheater/precalciner (NSP) rotary cement kiln at one cement manufacturing facility (referred to as Shui Ni 1 in this report) and a vertical shaft kiln (VSK) at another cement manufacturing facility (referred to as Shui Ni 2 in this report), which are both in Shandong Province, were selected to conduct the energy and emission assessments through collection of data. Based on analysis of the data collected during this assessment, several actions are suggested that could lead to reduction in coal use and reduction in emission of gaseous pollutants from the system.

8 Energy Intensive Industries, 8.3 Energy Efficiency Measures in Key Industrial Sectors, 8.3.3 Cement and Concrete

Energy Efficiency Improvement Opportunities for the Cement Industry

This report provides information on the energy savings, costs, and carbon dioxide emissions reductions associated with implementation of a number of technologies and measures applicable to the cement industry. The technologies and measures include both state-of-the-art measures that are currently in use in cement enterprises worldwide as well as advanced measures that are either only in limited use or are near commercialization. This report focuses mainly on retrofit measures using commercially available technologies, but many of these technologies are applicable for new plants as well. Where possible, for each technology or measure, costs and energy savings per tonne of cement produced are estimated and then carbon dioxide emissions reductions are calculated based on the fuels used at the process step to which the technology or measure is applied. The analysis of cement kiln energy-efficiency opportunities is divided into technologies and measures that are applicable to the different stages of production and various kiln types used in China: raw materials (and fuel) preparation; clinker making (applicable to all kilns, rotary kilns only, vertical shaft kilns only); and finish grinding; as well as plant wide measures and product and feedstock changes that will reduce energy consumption for clinker making. Table 1 lists all measures in this report by process to which they apply, including plant wide measures and product or feedstock changes. Tables 2 through 8 provide the following information for each technology: fuel and electricity savings per tonne of cement; annual operating and capital costs per tonne of cement or estimated payback period; and, carbon dioxide emissions reductions for each measure applied to the production of cement.

8 Energy Intensive Industries, 8.3 Energy Efficiency Measures in Key Industrial Sectors, 8.3.3 Cement and Concrete

Use of Alternative Fuels in Cement Manufacture: Analysis of Fuel Characteristics and Feasibility for Use in the Chinese Cement Sector

Cement manufacturing is an energy-intensive process due to the high temperatures required in the kilns for clinkerization. The use of alternative fuels to replace conventional fuels, in particular coal, is a widespread practice and can contribute to improving the global warming impact and total environmental footprint of the cement industry. This report consists of three sections: an overview of cement manufacturing technologies, a detailed analysis of alternative fuel types and their combustion characteristics, and a preliminary feasibility assessment of using alternative fuels in China. This report provides an overview of the technical and qualitative characteristics of a wide range of alternative fuels including agricultural and non-agricultural biomass, chemical and hazardous wastes, petroleum-based wastes, and miscellaneous waste fuels. Each of these alternatives are described in detail, including a discussion of average substitution rates, energy and water content of the fuels, carbon dioxide emissions factors, and change in carbon emissions per ton of coal replacement. Utilization of alternative fuels in cement kilns is not without potential environmental impacts; emissions concerns and their effective management are discussed in general as well as for each alternative fuel type. Finally, the availability of a variety of alternative fuels is assessed in China along with the opportunities and technical challenges associated with using alternative fuels in China’s cement manufacturing sector.

8 Energy Intensive Industries, 8.3 Energy Efficiency Measures in Key Industrial Sectors, 8.3.3 Cement and Concrete

Opportunities for Improving Energy Efficiency, Reducing Pollution and Increasing Economic Output in Chinese Cement Kilns (Proceedings of the American Council for An Energy Efficient Economy’s 2007 Summer Study on Energy Efficiency in Industry)

China produces roughly half of the world’s cement, a large share of which is made in energy inefficient, highly polluting kilns. The cement industry is a major source of multiple air pollutants, among them dioxins, mercury, particulate matter and greenhouse gas emissions. In 2005, just over one billion tons of cement was produced in China and cement demand will continue to be high in the near future as development goals are pursued.  In the kiln, production of clinker, the main ingredient of cement, consumes about 80% of the energy used at a cement plant. Clinkering is also the source of almost all carbon dioxide and toxic emissions produced from cement manufacture. This paper examines measures that can be used to retrofit or to replace older, inefficient Chinese cement kilns to improve their energy efficiency, reduce pollution and maximize the industry’s economic performance and output. We provide costs, savings and payback periods upon implementation for case studies around the world, and where possible, specifically in China. Fourteen of the technologies and measures examined have simple payback periods of three years or less.

8 Energy Intensive Industries, 8.3.3 Cement and Concrete

Opportunities for Improving Energy and Environmental Performance of China’s Cement Kilns

This report examines 22 technologies or measures that can be used to retrofit or to replace older, inefficient cement kilns to improve their energy efficiency. Such technologies can help China achieve two goals, often erroneously believed to be in conflict: (1) reduce energy use and pollution; and (2) maximize the industry’s economic performance and output. The barrier to their implementation is not the lack of economically feasible technology, but rather the lack of a mechanism to finance investment and outreach to the cement and financial sectors.Fourteen of the technologies and measures examined have simple payback periods of three years or less. At the current price of carbon, sale of associated carbon credits would yield an additional $1,300 – $850,000 on top of the energy cost savings (ranging from 0 to 3.4 GJ/t of fuel and -11 to 35 kWh of electricity), assuming the Clean Development Mechanism requirements could be met.  China produces roughly half of the world’s cement, most of which is made in energy inefficient, highly polluting kilns. The cement industry is a major source of multiple air pollutants, among them dioxins and dioxin-like chemicals, mercury, particulate matter and greenhouse gas emissions.

8 Energy Intensive Industries, 8.3 Energy Efficiency Measures in Key Industrial Sectors, 8.3.3 Cement and Concrete