The Study Of Environmental Impact Assessment In Cement Industry Function Expansion

Nowadays, the traditional work mode with the high energy consumption and the highemission still occupy a large proportion in cement industry in China, thus the environmentproblem caused by traditional ways is increasingly prominent. Because the cement kiln hasthe characteristic of high temperature, high pressure, large capacity and whole sealing, etc,it is suitable to dispose municipal sludge, urban waste, contaminated soil, other industrialwaste and so on. So the state and local governments emphasized numerous times thefunction of transformation for cement enterprises in related programs. In present, somecement enterprises have already begun to try cement rotary kiln co-processing whichachieved a good effect. In this paper, it studied the function of transformation for cemententerprises by using life cycle assessment and fuzzy analytic hierarchy process theory.Followings are the main researches:(1) Study on the fuzzy analytic hierarchy process which index values are fuzzynumbers, and which judgment matrix is established by using weight distribution. First of all,the author gives a brief introduction on the definitions and theorems of fuzzy sets and fuzzyanalytic hierarchy process. Secondly, to solve the problem that the relationship betweenaddition and subtraction and that between multiplication and division in fuzzy numbers isno longer the inverse operation and make the operational laws more correspond to reality,the author studies the multiplicative consistency of fuzzy reciprocal judgment matrix byintroducing the concepts of independent variable, dependent variable, representative systemand degree of freedom in classical mathematics. Then, the result reveals that it isunreasonable that if a fuzzy reciprocal judgment matrix satisfies the conditions ofmultiplicative consistency defined in some existing related literatures, then this matrix mustbe a precise reciprocal judgment matrix. Finally, based on the fuzzy cut set theory, using therelationships among elements of fuzzy reciprocal judgment matrix, the multiplicativeconsistency of fuzzy reciprocal judgment matrix is redefined. Thirdly, the author gives theconvert mathematical expression between fuzzy number complementary judgment matrixand fuzzy reciprocal judgment matrix, and proved the consistency unchanged of judgmentmatrix before and after conversion.Finally, the author combines the solving process ofpositive reciprocal judgment matrix of analytic hierarchy process, and gives the solvingalgorithm of fuzzy number complementary judgment matrix, then the author gives the algorithm of fuzzy analytic hierarchy process and comprehensive evaluation ofenvironmental impact.(1) Study on the current situation of the cement industry development in China. Firstof all, according to the development path of China’s cement industry, the author divides thehistory of cement industry development into five stages: the birth stage, the stagnation anddecline stage, the research stage, the development stage and the flourish of capacitystructure stage. Secondly, the author analyzed the current situation of the cement industrydevelopment in China. For decades, the cement industry in China has developed to thesustainable growth of capacity, the sustainable optimization of structure, the sustainablegrowth of concentration, the sustainable improvement of energy saving and emissionreduction, and the sustainable progress of technical equipment level. Thirdly, during thedevelopment of cement industry in China, the author pointed out some problems which areexcess capacity, low level of production technical, low concentration of cement production,etc. At last, the author analyzed the trend of future development for cement industry inChina. The key jobs of cement industry in our country are solving the excess capacity andadjusting industrial structure for a period of time in the future. At the same time, thegovernment should increase investment on the technology innovation, increase theproportion of high quality cement productions, and focus on developing green cementindustry.(2) Study on the function transformation of cement enterprises which aim to disposeurban waste and municipal sludge. The function transformation means, at the same time ofnormal cement production, dispose municipal sludge, urban waste, contaminated soil, andother industrial waste by cement rotary kiln co-processing which using the characteristicsof high temperature, high pressure, large capacity and fully enclosed in cement kiln. It is asignificant problem that what is the influence on the environment during the process offunction transformation, which directly affects the sustainable development of cementindustry. Authors using the life cycle assessment theory, comparative study theenvironmental impact of cement kiln co-processing and disposition of traditional of urbanwaste and sludge. There are five sewage sludge disposal. Two of those for cement kilnco-processing, namely transporting cement plant after dehydration or lime stabilization.The other three are traditional disposal methods, namely desiccation landfill, incinerationlandfill and dehydrated compost. City garbage disposal also has five. Two of those forcement kiln co-processing, namely cement kilns disposal after incineration, direct disposal of cement kiln and cement kilns consolidated disposal. The other two are traditionaldisposal methods, namely Sanitary landfill and Incineration Landfill.(3) Study on the expansion and measures for Cement business. At the present time,domestic cement companies focused on the use of cement kiln co-processing of municipalsewage sludge, municipal waste, industrial waste and contaminated soil in functiontransformation practice, so in this paper, the expansion in these areas are focused on toexpand. In addition, if the cement companies want to make the transition successfully, somesafeguards are needed. From the internal environment, companies need to complete the sixmajor changes: First, the management way should be changed from extensive to intensive;second, the energy structure should be changed from a one-time shift to alternative fossilfuel energy; third, in terms of quality varieties should be diversified from a singleecological transition; fourth is in production equipment, to make a transition from thelarge-scale to energy conservation; fifth is on the environmental protection, it should bechanged from high-carbon economy to a low carbon economy; sixth is the raw materialresources, changing from high-grade to low-grade. From the external environment, thegovernment needs to develop the following five policies. First of all, it is necessary toimplement a carbon trading mechanism, forcing cement companies functiontransformation;second is to improve the tax incentives and renovation subsidies, toincentive cement companies function transformation; third, the introduction of nationalstandards and norms to guide the transformation of cement enterprise functions; fourth isto clear " who pollute, who bear the economic and legal responsibility" to force cementcompanies function transformation; five is to carry cement kiln co-processing integrateddemonstration projects, leading cement companies function transformation.