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This post was last edited by ryam on 2010-11-18 at 18:19. It is a project proposal aimed at reducing the production costs of cement and improving economic efficiency by utilizing steel slag residues or ultra-fine powders. I hoped to submit it to Huaxin Cement’s Planning and Development Department, Technology Department, and Design Department, but since your company’s website is rather simple and does not provide phone numbers or email addresses for those departments, I had no choice but to post it on your company’s forum. I hope the technical staff at your company will take a look and forward it to relevant departments such as the Planning and Development Department and the Technology Department. Thank you! Plan for Utilizing Steel Slag to Reduce Cement Production Costs and Improve Economic Efficiency (Simplified Version) 1. Brief Introduction to Steel Slag and Its Applications in the Cement Industry. Steel slag is a solid waste generated during the metal smelting process in steel plants; its output amounts to 10%~15% of the steel produced. Nationwide, 5000~9000 million tons of steel slag are generated each year. The main components of steel slag are iron oxide and calcium oxide, which are similar to the main components in cement clinker. ①By using steel slag as raw material, no carbon dioxide is emitted during calcination, which helps to reduce greenhouse gas emissions. ②Using steel slag to replace iron ore in the batching process not only makes full use of industrial waste but also reduces energy consumption. Using slag alone as a raw material saves approximately 3 kilograms of standard coal per ton of clinker, while using steel slag alone saves approximately 4 kilograms of standard coal per ton of clinker. 2 Comprehensive Utilization of Steel Slag by a Cement Group in Hebei A certain cement group in Hebei (hereinafter referred to as “the cement group”) is committed to energy conservation and reduction, as well as the comprehensive utilization of solid waste; it actively promotes the use of industrial waste such as steel slag. In 2006 alone, the cement group utilized over 5 million tons of more than 10 types of industrial solid waste, including steel slag, slag, fly ash, phosphogypsum, and desulfurization gypsum. ②In 2007, a cement group utilized 6.7 million tons of more than a dozen types of industrial waste, including steel slag and fly ash. ③From January to May 2008, the headquarters of a certain cement group used steel slag as a raw material to produce 1.19 million tons of clinker, saving an equivalent of 4,760 tons of standard coal in terms of energy consumption ； The low-voltage motor saved 530,000 kWh of electricity, equivalent to 190.8 tons of standard coal. From January to May, 1.6178 million tons of cement were produced, representing a 12% increase in output compared to the previous year. The comprehensive energy consumption per ton of cement decreased by 12.5%, resulting in a reduction of 26,800 tons in the use of standard coal. ④From 2006 to 2008, by using steel slag as a substitute for iron ore, and assuming an annual production of 3.2 million tons of clinker, 16,000 tons of standard coal could be saved each year. Currently, the company’s comprehensive energy consumption per ton of cement has been reduced to 113.08 kilograms of standard coal, resulting in a total savings of 59,800 tons of standard coal over the past two years. ⑤From 2006 to 2008, calcium oxide derived from steel slag was used in place of that produced by the decomposition of calcium carbonate, thereby preventing carbon dioxide emissions – approximately 100,000 tons of CO2 were reduced each year. ⑥On April 1, 2008, a cement group and the Yangjiazhangzi Economic Development Zone in Huludao established a partnership; with a total investment of 600 million yuan, they launched a project to construct a cement clinker production line with a daily output of 4,500 tons. This line makes use of the abundant local industrial waste materials such as magnesium slag, furnace slag, steel slag, fly ash, and slag as alternative raw materials and admixtures in cement production, by employing advanced pre-decomposition firing technologies in dry process kilns. ⑦Starting from 2008, over the next two years, enterprises will further expand the types and quantities of industrial waste utilized; by the end of the 11th Five-Year Plan period, the annual comprehensive utilization of industrial waste is expected to reach 20 million tons. 3 Challenges in the Comprehensive Utilization of Steel Slag: With the development of technologies for the comprehensive utilization of steel slag, people are making more extensive use of the beneficial components contained in it. Instead of limiting its use to initial applications such as land reclamation and road construction, or focusing solely on iron recovery, the residual slag is now utilized in various ways such as in sintering, agricultural fertilizers, iron production, cement manufacturing, water treatment, and building coatings, building on the basis of iron recovery. In the era when steel slag was primarily used for land reclamation and road construction, its pretreatment was relatively simple. As the comprehensive utilization of steel slag progresses to the point where the residual slag is to be applied in various fields such as sintering, cement, fertilizers, iron production, and concrete, the pretreatment of steel slag becomes a challenge. Due to its high density, hardness, and special structure, as well as being a combination of iron and slag that may even contain large iron particles, cone crushers driven by springs or hydraulics are unable to grind it finely. The slag with a particle size of less than 10 mm, which is required for applications such as cement and sintering, can only be reduced to a size of 40–60 mm through the jaw crusher-based pretreatment process for steel slag. If this sized slag is fed directly into ball mills for further processing, it will inevitably result in low efficiency, significant energy waste, and increased additional production costs – costs that may even exceed the added value generated by utilizing the steel slag. Therefore, the technical shortcomings in the pretreatment of steel slag have become a bottleneck restricting the comprehensive utilization of steel slag, and the main challenge in pretreatment is its comminution. It solves the problem of fine crushing of steel slag, enables simplification of the process flow and reduction in the number of stages, results in a very fine product particle size, and allows for an increase in the iron recovery rate as well as a higher quality of the slag-iron mixture ； The fine particle size of the tailings meets well the requirements of modern processing techniques that emphasize more crushing and less grinding, thereby improving the efficiency of the mills, increasing output per unit time, saving energy and reducing costs. 4 Solutions and Their Application in Hebei. The Beijing Research Institute of Mining and Metallurgy (under the jurisdiction of the State-owned Assets Supervision and Administration Commission) developed an efficient pretreatment process for steel slag for industrial use back in the 1990s. This process utilizes jaw crushers for rough crushing, and inertial cone crushers equipped with cutting-edge technology for fine crushing, reducing the size of the steel slag to less than 5 mm in over 90% of the cases. Magnetic separation is used to obtain three types of slag-iron products, while the residue with a particle size of less than 5 mm constitutes over 90% of the total output; this residue can be used in cement production, sintering, aggregate manufacturing (for highways, runways, ready-mixed concrete), coatings, and other applications. In regions such as Hebei, Shandong, Liaoning, Gansu, and Jilin, the tailings from steel slag are primarily used in the cement industry, where they help increase cement production and its quality. They also reduce the costs of raw materials used in cement production as well as energy consumption, minimize waste gas emissions, lower production costs, and enhance economic benefits. In the field of advanced processing of steel slag residues, the dry method can produce ultra-fine steel slag powder with 95% of particles being less than 10 microns, while the wet method can yield ultra-fine steel slag powder with 99% of particles being less than 2 microns. This powder can be used to manufacture special cements, or it can be added to ordinary cement to improve its properties. To date, Beijing Kate Crusher Co., Ltd., affiliated with the Beijing Institute of Mining and Metallurgy, has established 15 steel slag treatment production lines in the Tangshan area of Hebei Province (8 in other provinces). In addition to the slag-iron products obtained through magnetic separation and crushing, it mainly supplies steel slag residue to a cement company in Hebei – with over 90% of the material having a size of less than 5 mm. Each production line can process 400–500 tons of steel slag per day, producing 360–450 tons of fine-grained steel slag material. In total, these lines supply approximately 3,600–4,500 tons of fine-grained steel slag material to a cement company in Hebei each day, resulting in an annual supply of around 1.4 million tons of steel slag products. A cement group in Hebei has used steel slag as a raw material for cement production, resulting in an annual reduction of 90,000 tons of CO2 emissions, 20,000 tons of standard coal saved, a 12% increase in production, and a reduction of over 12.5% in the overall energy consumption per ton of cement produced. These production lines have made a significant contribution to environmental protection in a certain cement company in Hebei Province and in Tangshan City. ①Calcium oxide from steel slag was used in place of the calcium oxide produced by the decomposition of calcium carbonate, thereby preventing carbon dioxide emissions – approximately 90,000 tons of CO2 are reduced each year. 5 Reasons for Planning to Apply in Hubei: 1. Hubei has steel companies, providing an adequate supply of steel slag resources. 2. Hubei is home to a nationally renowned large-scale cement company (your company) – Huaxin Cement Co., Ltd. 3. There is a large cement market. 4. Currently, there is a need to reduce production costs, improve product performance, and develop new products. 5. **From the Ninth Five-Year Plan to the 12th Five-Year Plan, the requirements regarding environmental protection and energy conservation were gradually raised.** Furthermore, some of the promoters (our company) are from Hubei and are concerned about the progress and pace of Hubei’s development. Therefore, it is planned to collaborate with steel companies and Huaxin Cement Company in Hubei to promote the comprehensive utilization of steel slag, particularly the application of steel slag residues and highly refined ultra-fine powders in the cement industry. We sincerely hope that Huahua New Cement will understand and discuss this review and introduction. We urge your company to visit the Hebei region to observe industrial applications, conduct discussions and analyses, with the ultimate goal of using steel slag to reduce cement production costs and increase the added value and economic benefits of cement products. Contact person: Chen Bang. Phone: 01063299198. Email: kaite@bgrimm.com. Address: No. 1 Wenxing Street, Xizhimenwai, Xicheng District, Beijing. Website: www.bgrimm.com. Beijing Kate Crusher Co., Ltd., March 16, 2009. List of reference materials: Source: The official website of Jidong Cement. Address: http://www.jdsn.com.cn/news/20092/200922165137.htm. Article title: Jidong Cement in Tangshan adopts ten strategies to gain an advantage. Publication date: February 2, 2009. Excerpt: “Thirdly, it is necessary to pursue a path of circular economy, making use of the advantages of the cement industry to improve the capacity and efficiency in handling ‘three types of waste’, thereby saving energy, reducing costs, and enhancing overall competitiveness.” ” Source: Jidong Cement’s official website Address: http://www.jdsn.com.cn/gfcy_nr.asp?id=80 Article title: Phase III Project of Jidong Cement’s Fengrun Company Publication date: June 2006 Excerpt: “3. Circular economy demonstration project: In line with the development principles of a circular economy based on reduction, reuse, and resource utilization, this project leverages the role of the modern cement industry as a ‘cleaner’ for urban industries, turning waste into resources.” Tangshan is one of China’s major heavy-industry hubs, home to numerous steel, coal, and ceramics enterprises. These enterprises generate large amounts of industrial waste such as steel slag, coal gangue, and slag each year, and these wastes cause significant pollution to the surrounding environment. During the cement production process in Jidong, industrial waste such as steel slag and slag is made full use of as auxiliary materials in the raw material and cement grinding stages; once the project is operational, it will be able to consume up to 1 million tons of industrial waste per year. “ Source: Tangshan Information Network Address: http://www.tsxxg.com/*n*.asp?showID=24418 Article title: Notice of a Stakeholder Consultation Meeting Held by Jidong Cement Publication date: 2009-1-6 Excerpt: “Jidong Cement’s Fengrun Phase III project involves three new clinker production lines with a daily capacity of 4,500 tons each.” The Fengrun Phase III project for producing clinker from non-CO2 emitting raw materials (hereinafter referred to as this project) aims to reduce CO2 emissions by using steel slag and other waste materials to replace some of the carbonaceous substances in the raw materials used for clinker production. The conventional cement production process uses limestone as the main component of the raw material. During calcination, limestone produces calcium oxide and carbon dioxide; this carbon dioxide emitted during calcination is the primary source of carbon dioxide generated in the whole clinker production process. The carbon dioxide produced in this process is released directly into the atmosphere. Steel slag is a type of solid waste generated by steel mills. Its main components are iron oxide and calcium oxide, which are similar to those in clinker; moreover, no carbon dioxide is emitted during its calcination. Therefore, using steel slag in place of some limestone as raw material can help reduce greenhouse gas emissions. This project uses calcium oxide from steel slag to replace the calcium oxide produced by the decomposition of calcium carbonate, thereby avoiding carbon dioxide emissions; the annual emission reduction is estimated to be around 100,000 tCO2. ” Source: Hebei Energy Conservation Network Address: http://www.hbjnw.net/xhhk/ShowArticle.asp?ArticleID=584 Article title: Jidong Cement Company Makes Solid Progress in Energy Conservation and Emission Reduction Publication date: 2008-7-31 Excerpt: “Using steel slag in place of iron ore, and slag in place of bauxite in the mixing process not only makes full use of industrial waste residues but also reduces energy consumption; based on an annual production of 3.2 million tons of clinker, this approach can save 16,000 tons of standard coal per year.” Currently, the company’s comprehensive energy consumption per ton of cement amounts to 113.08 kilograms of standard coal; over the past two years, a total of 59,800 tons of standard coal have been saved. ” “It promotes the comprehensive utilization of resources, handling 6.7 million tons of industrial waste each year…… Jidong Cement is willing to take on the role of a \"sweeper\" in industrial cities, striving to advance the comprehensive utilization of resources. In 2007, the company utilized 6.7 million tons of more than a dozen types of industrial waste, including slag, steel slag, and fly ash. In the next two years, enterprises will further expand the types and quantities of industrial waste utilized; by the end of the 11th Five-Year Plan period, the annual comprehensive utilization of industrial waste is expected to reach 20 million tons. Source: Hebei Economic Industry Network Address: http://www.hebgy.gov.cn/*n*/news/2008-07-17/20080717083910.html Article title: Tangshan Jidong Cement Takes Real Action on Energy Conservation and Emission Reduction Publication date: July 7, 2008 Excerpt: “(IV) Steel slag and slag mixing projects.” The company uses steel slag to replace iron ore and slag to replace bauxite in its mixing process, which not only makes full use of industrial waste residues but also reduces energy consumption. Using slag alone can save approximately 3 kilograms of standard coal per ton of clinker, while using steel slag alone can save about 4 kilograms of standard coal per ton of clinker. Using both steel slag and slag together can save approximately 5 kilograms of standard coal per ton of clinker. In 2007, the company’s headquarters used steel slag as a raw material to produce 3.04 million tons of clinker, saving 12,160 tons of standard coal. ” “——From January to May 2008, the company’s headquarters produced 1.19 million tons of clinker using steel slag as a raw material, resulting in energy savings equivalent to 4,760 tons of standard coal ； The low-voltage motor saved 530,000 kWh of electricity, equivalent to 190.8 tons of standard coal. From January to May, 1.6178 million tons of cement were produced, representing a 12% increase in output compared to the previous year. The comprehensive energy consumption per ton of cement decreased by 12.5%, resulting in a reduction of 26,800 tons in the use of standard coal. ” Source: Website of Shaanxi Building Materials Association Address: http://www.sxjiancai.com/sql/Article/news/hynews/200802/2339.htm Article title: Jidong Cement: Strengthening Its Overall Strength through Technological Progress Publication date: February 2008 Excerpt: “At the beginning of January this year, Jidong Cement signed a cooperation agreement with China National Building Materials Group Corporation.” Under this agreement, the two parties will work together to build the world’s largest manufacturing base for cement technology and equipment, the largest domestic manufacturing base for non-metallic new materials, demonstration sites for the development of a circular economy and environmental protection industries, as well as Sinoma Group’s largest industrial manufacturing base. At the same time, Jidong Cement Company will be developed into China’s largest cement manufacturer. The signing of the agreement marks Jidong Cement’s acceleration in developing a circular economy. ” “While accelerating its development pace, Jidong attaches great importance to the utilization of \"three wastes,\" especially industrial waste residues. The slag that many companies discard as waste has become raw materials for Jidong and is put to use there. Zhang Zengguang, the company’s chairman, said, “The modern cement industry is an important link in the circular economy value chain, and using waste to produce cement is an emerging trend.” As the largest cement manufacturer in northern China, it is our responsibility to contribute to improving the urban environment of Tangshan! ”Jidong has successively studied the utilization of coal gangue, iron ore tailings, alkali slag, steel slag, and domestic waste, achieving results in each case. In 2006 alone, the company utilized 5 million tons of more than 10 types of industrial solid wastes, including slag, steel slag, fly ash, phosphogypsum, and desulfurization gypsum. ” Source: Cement Information Network Address: http://www.infocement.com/ywdt/yaowen/200706/788.html Article title: Zhu Yunlin’s speech at the groundbreaking ceremony for Jidong Cement’s Fengrun Phase III project Publication date: 2007-06-08 Excerpt: “First, to establish a model project for circular economy.” In line with the principles of circular economy development centered on \"reduction, reuse, and resource recovery,\" it leverages the role of urban industries as \"sweepers\" to transform waste into resources, enabling the secondary use of resources and energy, thus turning this project into a true model of circular economy in Tangshan. Once completed, the project will enable full utilization of the abundant local industrial waste resources, with steel slag, slag, fly ash, ferroaluminovanadate, bauxite, waste silica, and waste sandstone being used as raw material components ； Using fly ash, slag, steel slag, phosphogypsum, desulfurization gypsum, etc. in cement production ； Through careful material selection and optimized mining practices, \"waste-free mining\" in the mine is achieved; building on an existing capacity to process nearly 5 million tons of various industrial solid wastes per year, an additional 4 million tons of such wastes can be processed. ” Source: Huludao News Network Address: http://huludao.nen.com.cn/Article/ztxw/yuanqu/200804/38605.html Article title: Jidong Cement’s 4,500-ton-per-day production facility to be established in Yangjiazhangzi Publication date: 2008-4-22 Excerpt: “On April 16, the Yangjiazhangzi Economic Development Zone in Huludao and Tangshan Jidong Cement Co., Ltd. reached a cooperation agreement. With a total investment of 600 million yuan, this project aims to utilize local industrial waste such as magnesium slag, furnace slag, steel slag, fly ash, and slag as alternative raw materials and admixtures in cement production. It also employs advanced pre-decomposition firing technology in dry process kilns, enabling the production of 4,500 tons of cement clinker per day; this facility will be established in the Yangjiazhangzi Economic Development Zone.” ”