| Fly ash, a byproduct of coal combustion, is a dust residue discharged with boiler flue gas when burning coal. With the wide use of coal, there is an increasing trend of fly ash emissions all over the world. However, comprehensive utilization of fly ash becomes a pressing problem. Piling up fly ash not only occupies valuable land but also harms human health and environment directly or indirectly. Perceived as solid waste for a long time, fly ash has not been utilized rightly and leads to severe environmental pollution. With the development of society, more and more research and practice indicate fly ash is a kind of alternate resource to reuse. Comprehensive utilization of fly ash can turn the "Waste" into Wealth and change the harm into benefit, which make it one of research hotspots at present. There exist many problems in the comprehensive utilization of fly ash in China, such as low utilization ratio and level, unstable utilization approaches, second pollution et. al. In this case, we should carry out scientific, systematical, objective evaluation and studies on the comprehensive use of fly ash in order to actively guide and promote its utilization, and to stimulate the development of resource-saving society, as well as to facilitate the sustainable development of society, economy, resource and environment.Based on the comprehensive utilization of fly ash in Xiamen Songneng Fly Ash Dvelopment Co, Ltd, in this thesis, benefits and problems from comprehensive utilization of fly ash in this company are evaluated systemically. Indices of economic benefit, social benefit, environmental benefit, management, policy as well as technology are analyzed by establishing evaluation index system of comprehensive utilization of fly ash. Function, meaning, calculation method and evaluation standard of qualitative and quantitative indices are defined. Based on the acquisition, operation and objectivity of data, a large number of quantitative indices and calculation formulas are set in the economic benefit and technological benefit indices. Qualitative indices are used in the social benefit, environmental benefit, policy, management indices. All those improve the practicability and objectivity of the index system. In this thesis, evaluation of comprehensive utilization of fly ash in the Songyu Co, Ltd.is made by integrated evaluation methods based on the established evaluation index system. Methods and approaches for completing the evaluation of comprehensive utilization of fly ash are concretely analyzed theoretically. Relationship among indices is discussed to make indices system comprehensive and reasonable. According to characteristic of indices and acquisition of data, weights of evaluation factors and final evaluation values of indices are identified by the combination methods of Analytic Hierarchy Processing, Objective Oriented Comparison, Expert Grading, and Delphi. According to various index weights, integrated evaluation value of comprehensive utilization of fly ash in the company is calculated using weighted average method. The final score of Songneng Co, Ltd is 68.4. The company is evaluated as the third grade enterprise of comprehensive utilization of fly ash. Advices that Songneng Company should improve production management required by Cleaner Production Audit, ISO9001 Certification, and ISO14001 Certification are mentioned by analyzing evaluation result and reasons. Enviromental protection education should be strengthened for workers. In addition, integrated management should be facilitated and management system and policy should be amplified. For the purpose of broadening the utilization channels of fly ash, improving the comprehensive utilization of fly ash as well as enhancing the product added value, the company should promote the development of deep processing projects of fly ash, such as the application in the wastewater treatment in environmental protection field, emphasize the increase of social benefit from utilization of fly ash and comprehensive utilization ratio of fly ash.In this thesis, from the perspective of promoting the comprehensive utilization of fly ash in the Xiamen Songneng Co, Ltd, worldwide situation of comprehensive utilization of fly ash is analyzed and experimental studies on the adsorption of copper in the wastewater using fly ash are carried out based on theoretical foundation of sustainable development, circular economy and cleaning production. In the experimental study, effects on the removal of copper in the wastewater by fly ash are analyzed under different factors of pH, temperature, original copper concentration, granularity, fly ash dose and time. Further theoretical explanation on various influence factors is presented. From the results of experimental study, we conclude fly ash can be used as a cheap, high efficiency adsorbent in wastewater treatment and initially validate the technological feasibility of utilization of fly ash in the wastewater treatment field. Concrete advices of future development on further prolonging production chains in the Xiamen Songneng Fly Ash Development Co, Ltd. are provided. Based on the little fly ash fineness of the company, when the company begin research and utilization of fly ash in the treatment of copper wastewater, under the consideration of economical factor and adsorption effect, adsorption equilibrium time should be set 5 hours; proportion of water to fly ash should be set 3 g/100 mL; pH of wasterwater should be adjusted to around 6; treatment of low concentration copper wastewater should be done under the room temperature. At present, worldwide research on municipal wastewater treatment using fly ash has turned to be applied in practice, which paves a solid way for the utilization of fly ash in the field. Level of fly ash utilization in Xiamen Songneng Co, Ltd. is not high relatively and utilization ways are single and extensive. The research provides reference for expanding application fields of fly ash in the company especially in the field of waterwater treatment. It can also promote the comprehensive utilization level of fly ash and prolongs production chain.
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