The Comprehensive Utilization of Fly Ash in China as Seen from European Building Materials

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Personally, I think this article is somewhat useful as a reference, and I hope everyone will come up with newer and more feasible methods for the recycling of coal ash. The Comprehensive Utilization of Fly Ash in China as Seen from European Building Materials – Li Jiying 1. Environmentally Friendly and Energy-Efficient European Building Materials Europe was originally beautiful, and with the addition of bricks and colored tiles, it has become even more colorful. In terms of urban hardening, Europe has made extensive use of blocks. Plazas, flower beds, and curbs are all constructed using bricks; there is a wide range of such bricks available, including structural bricks, grass tiles, sidewalk bricks, and plaza bricks, all of which feature bright colors and an elegant appearance. 　　Through our research, we learned that the blocks used in Europe are made from fly ash and pozzolana. They have been a great inspiration to us in terms of waste utilization and environmental protection. Their successful practices are also worth learning from. 　2. Accelerate the use of fly ash in the field of new building materials. China’s overall recovery rate for mineral resources is between 30% and 50%, which is 10–20 percentage points lower than the world average ； Each year, the solid waste and recyclable resources that could be utilized effectively amount to over 50 billion yuan in value, yet they are not put to use; this is one of the key reasons for rising costs and poor economic performance for enterprises. Furthermore, if the comprehensive utilization rate of solid waste in our country increases by 1 percentage point, it would result in a reduction of about 10 million tons of waste being discharged each year. It is evident that energy conservation and comprehensive utilization of resources are also important ways to address environmental pollution. 　　Fly ash refers to the general term for the ash and slag discharged during the combustion of coal powder in industrial production. With the construction and operation of large coal-fired power plants, the amount of fly ash generated is increasing at an average rate of 15% per year, accounting for 60% of industrial solid waste. Therefore, the comprehensive utilization of fly ash is one of the key priorities in the management of industrial solid waste in China. The history of comprehensive utilization of fly ash in our country began with the Sanmenxia Dam project in the 1950s. In this project, 33,000 tons of fly ash were used in the concrete, which resulted in a savings of 21,300 tons of cement. This not only helped to reduce costs by saving cement, but it also played a key role in preventing cracks in the dam, enhancing its impermeability, increasing its strength over time, and improving the quality of the structure. It marked a milestone in the utilization of fly ash in China. 　　In recent years, **and the local authorities have introduced a series of policies and regulations that have greatly promoted the comprehensive utilization of fly ash. To date, the use of fly ash in construction materials, road construction, dam building, engineering backfilling, concrete, and mortar has seen significant progress. From the perspective of environmental protection and energy conservation, fly ash has become a construction material that can replace clay, and its use is becoming increasingly widespread. To protect arable land, **the relevant ministries have issued orders to ban the use of clay for brick and tile production within a set time frame, and this measure has already been put into effect in some cities. The use of fly ash to produce new building materials is actively promoted by **industrial policies. 　3. Exploration and Practice of Comprehensive Utilization of Fly Ash at Huangdao Power Plant Huangdao Power Plant is a thermal power plant with a history of over 20 years; its total installed capacity is 670 MW, and it generates 400,000 m3 of ash per year. Currently, the plant has approximately 7 million m3 of fly ash stored. Due to the failure to utilize the fly ash accumulated over the years in a timely manner, the large amounts of ash stored in the two ash dumps are currently causing certain environmental harm to the areas where they are located. Similarly, with the further development of the power plant and the planning and construction of Phase 3, the costs associated with ash disposal and the maintenance of ash storage areas are increasing year by year. Therefore, the digestion and utilization of fly ash has become a key issue that enterprises focus on researching and solving. 　　In 1999, after thorough investigations and evaluations, Huangdao Power Plant established a new building materials company. It introduced a fully automatic concrete block production line from the German company Martha, with an annual production capacity of 250,000 cubic meters of concrete blocks, allowing for the use of 100,000 cubic meters of fly ash in the production process. As concrete blocks represent a new type of building material that is low in energy consumption, pollution-free, easy to maintain, provides good sound insulation, and has a wide range of applications, their load-bearing variants offer advantages such as a weight that is 20%–30% less than that of walls built with solid clay bricks, an increase in work efficiency of 30%–50%, a reduction in the total cost of construction by 5%–10%, and an increase in usable area by 2%–5%. Coupled with policy support, there has been strong demand for these products since they were put into use, to the point where supply cannot keep up with demand. The new building materials company thus became a driving force for Huangdao Power Plant to achieve another round of growth and leapfrog development under market economy conditions. The 50 hectares of land at the Phase 1 ash dump have also been converted for commercial use. 　　Next, Huangdao Power Plant will cooperate with the Italian company Gambali to establish a fully automated production line capable of manufacturing 13 million colored tiles per year. This project primarily introduces the fully automatic colored concrete roof tile production line from the Italian company Votex, which boasts advanced technology and top-notch equipment worldwide. By utilizing Gambaali’s production techniques and adding fly ash emitted by the Huangdao Power Plant, colored tiles with properties such as environmental friendliness, waste utilization, thermal insulation, and soundproofing are manufactured. Considering **policies and the actual conditions in Qingdao, the prospects for mid-to-high-end colored tiles are promising. In particular, these tiles feature bright colors, attractive designs, high strength, water resistance, and weather resistance; they are products recognized under the \"Ninth Five-Year Plan\" and \"Tenth Five-Year Plan\" housing improvement programs. With the evolution of people’s consumption and aesthetic concepts, demand for colored tiles is expected to increase significantly in the coming years. At present, the joint venture Huaoeu Gamba Li Roofing Products Co., Ltd. has been established, and it is expected to begin operations officially in April 2003. 　　At the same time, Huangdao Power Plant will launch the second phase of the new building materials company, in line with market conditions, to raise the annual production volume of fly ash blocks to 500,000 m3. Now, the dry ash removal projects required for the comprehensive utilization of fly ash have been fully completed. Since April 2002, Huangdao Power Plant has achieved continuous zero emissions of dry ash from its 4 boilers. The feasibility study and preliminary work for the dry slag disposal project have been completed, and by the end of 2003, Huangdao Power Plant will be able to dispose of slag in a dry manner instead of using seawater for this purpose. In this way, by expanding the external sales of dry ash and intensifying the development and comprehensive utilization of fly ash, Huaoeu New Building Materials and Huaoeu Gamba Li Roofing Products Company will be turned into the nation’s top research and development center for new building material technologies, the largest production base for new building materials, and a model site for the comprehensive utilization of fly ash. Huangdao Power Plant will strive to become the first coal-fired power plant in the country to achieve zero ash emissions by the end of 2005, thereby realizing the goal of eliminating ash dumps. This post was last edited by xssn2005 on 2009-2-16 12:08.]