Building a reasonable path of wall materials industry development under the goal

（Guangxi University of Finance and Economics, Nanning, Guangxi, 530003）

Abstract. Modern architecture is an important part of the consumption of energy and materials. With the deteriorating global environment and increasingly reduced resources, maintaining the sustainable development of the building materials and improving the comprehensive utilization rate of construction resources have become a widespread concern. At present, China's research on the recycling of the building material resources has made breakthrough achievements, but there are still technical and social identity issues. The development of wall materials industry should follow: the recycling of the materials, the recycling of the general waste in the construction and the application of the new recycling building materials, and should be led by the government, and form the protection of building resources in the "top-down" manner.

Key words: Wall material industry; circular economy; rational path; construct

Wall materials industry is an important basic raw material industry, which plays an important role in the development of the national economy. The traditional wall materials industry is the typical resources and energy consumption oriented industries. During its rapid development at the same time, it causes excessive consumption of resources and serious pollution of the environment. Wall materials industry accounts for the bulk of china's energy use, which accounts for 9% of the national energy consumption, 13% of the national industrial energy consumption, and the energy consumption of ten thousand Yuan is nearly 5 tons of standard coal, and the energy consumption is basically non-renewable fossil fuels -- coal and oil.

Taking the cement industry as an example, the recoverable deposits of the limestone resources of the country which is the main raw material to produce cement is only 54.2 billion tons. Calculated from the amount of annual consumption of the limestone cement production in our country at present, it can only last for decades and the resource depletion problems are close at hand. From the environmental point of view, the annual emissions of CO2, SO2 of the wall materials industry accounted for 1/4 and 1/10 of the national industry's total emissions. The dust emissions also accounts for a large proportion in the national industrial emissions, which has greatly affected the emission of more and more serious greenhouse gas, the formation of acid rain and the air quality. Therefore, to proceed along a new road to industrialization of a high technological content, good economic returns, low resource consumption, less environmental pollution, human resource advantages full played, in the sustainable development of wall materials industry at the same time, the building materials market should realize the coordinated development of economy, society and the environment, and make the ecological gradually into the benign cycle.

In view of the above, the following will discuss the topic.

1. The concept of circular economy

With the goals of circular economy, to develop the wall materials industry first of all need to grasp the inherent requirements of circular economy, and then construct a reasonable path in the development model in line with its internal requirements. The following defines it from the broad sense and narrow sense.

1-1. The generalized concept of circular economy

Wu Zongjie and Li Jianmin thinks that the circular economy covers three aspects of economic development, social progress, ecological environment, and the pursuit of the ideal combination state between the three systems. Ma Shijun thinks that the essence of sustainable development is the coordinated development of subjectivity in life and its habitat work environment, production environment and the social cultural environment. Wu Shaozhong thinks that the circular economy is to control the waste in the production of human activities, establish the repeated and natural recycling mechanism, count human production activities into the natural cycle, and maintain the natural ecological balance. Feng Zhijun thinks that the development of circular economy is a profound revolution of paradigms. This new paradigm and the production process end control mode have essential distinctions: change the emphasis from human productivity to natural capital, emphasizing to improve resource productivity, with the realization of "wealth doubled, resource use reduced less than half", namely the so-called "four times leap". Wu Jisong thinks that circular economy is to continuously improve the efficiency of resource use in the whole process of resources, production, product consumption and waste in the system of human, natural resources and science and technology, to change the traditional development increasing relying on resource consumption to economic development relying on Ecotype resource recycling. Zhang Luqiang and Zhang Lianguo put the circular economy as a complex system research composed of economic system, social system, natural system of society -- the economy -- nature, and point out that this system is not a purely spontaneous evolution, but a man-made ecosystem after the grasp of self-organization of the natural ecological system, economic cycle system and social system. The generalized circular economics is to study the self-organization of the artificial ecosystem and integrated knowledge system of material, energy, information circulation.

1-2. The concept of circular economy in a narrow sense

Zhu Dajian points out that circular economy is spoken for the linear economy of the high consumption and high emission since the campaign of industrialization and is a kind of economic development mode friendly to the earth. It requires the organization of economic activity to be the closed loop process of "natural resources -- products and supplies -- renewable resources". All the raw materials and energy can be reasonably utilized in the ongoing cycle of the economy, so as to limit the impact of economic activities on the natural environment in a degree as small as possible. Mao Rubai thinks that circular economy is the closed material flow mode of "resource consumption -- products -- renewable resources" compared to open (or single) material flow pattern of "resource consumption -- products -- waste" in the traditional economic activities. Xie Zhenhua thinks that the circular economy is a new economic paradigm at the stage that the ecological environment becomes the restrictive elements of the economic growth and the good ecological environment becomes the public wealth. It is a new economic form on the basis of the equality of the human condition and welfare and the maximum of the welfare of all members of the society as the goal, and its essence is to adjust the human relations of production. Ma Kai thinks that circular economy is a key to the efficient use of resources and recycling. Duan Ning thinks that circular economy is short for a closed-loop flow of material economy. Ren Yong thinks that circular economy is a new economic development model to implement "reduction, reuse, recycle and harmless" management regulation of resource flow mode in the social production and reproduction activities, which has a high ecological efficiency.

2. Analysis of the current development situation of wall materials industry

Through the comparison of the inherent requirements of circular economy, the current wall materials industry in China is still facing many problems. Wall materials industry is the main industry in the development of circular economy "three wastes", especially the use of industrial waste residue. Most of the waste residue is eliminated by the wall materials industry. In the utilization of waste residues, China's cement industry achievement is very significant. Since the 50-60's in the twentieth century, we already began to use industrial waste residue, and in the 70-80's, the variety and quantity of industrial waste residue is in growing. Since the 90's we dispose the city garbage, sewage sludge and some toxic and harmful substances, which has made considerable economic benefits and social benefits of enterprises.

The production of new building materials using various industrial waste residues is an important way for the wall materials industry to disposal waste. For example, we can use coal gangue, fly ash, carbide slag, slag and other industrial waste slag to produce a variety of new wall materials, roofing and insulation materials. We can also use a variety of industrial gypsum (including flue gas desulphurization gypsum) to produce plaster board gypsum; use the bagasse and other plant fibers to produce fiber boards. According to incomplete statistics, in 2004 the national comprehensive utilization of industrial waste is 0.36 billion tons, making the new wall proportion reach 35%. The annual energy which can be saved reaches about 72 million tons of standard coal, saving 1.1 million acres of land. Among them, the largest waste residue utilization is the volume of fly ash and coal gangue.

3. Building a reasonable path under the guidance

of the analysis

Circular economy is the product of close combination of the environment and the economy, and is essentially a kind of ecological economics. It is based on the closed material flow, using the ecology rule to organize economic activity into the recycling model of "resources -- products -- renewable resources" and the feedback process of "low mining -- high utilization -- low emissions", to bring the economic system harmoniously into the circulation of substances of the natural ecological economic system, to achieve the ecologicalization of the economic activities.

The guiding ideology of circular economy development of wall materials industry is: take the scientific outlook on development as the guidance, in order to save energy and resources and protect the environment as the center, with the cement, wall and other industries as the focus, the clean production as the foundation, in order to improve the utilization rate of resources and reduce emissions, with new technology and system innovation as the power, relying on the national laws and regulations and policy measures, relying on the market operation, relying on all the participation and unremitting efforts, construct the wall materials the industry into a new green industry with stronger capacity for sustainable development, and economic, social and environmental coordinated development.

Specifically, the reasonable path of wall material industry development is as follows:

3-1. Improve the quality of products and prolong the service life.

Improving the quality of products and prolonging the service life is the most fundamental method, because only prolong service life is the most environment-friendly and most economical method. Simply speaking, while the service life is long, the cost of the material is relatively reduced, the material consumption is reduced, and the resource consumption is reduced, and the damage to the environment is reduced. But to improve the quality of products needs to increase scientific research strength and raise the level of management.

Taking the concrete for example, we know that prolonging the service life is to increase the durability of the concrete, and the durability of the concrete in a narrow sense mainly includes 6 aspects of impermeability, frost resistance, resistance to corrosion, carbonization, alkali-aggregate reaction and the corrosion of the reinforcing bar. So we should start in the 6 factors and increase scientific research strength, so that the service life of the concrete will be increased from 50 years to 100 years or even longer time.

Constantly improving the quality and function of wall material products not only is the eternal theme of both enterprises and the management, but also the superior choice of promoting the development of circular economy and improving the sustainable development ability of the building materials enterprises.

3-2. Save energy and improve the energy efficiency.

As far as the non-renewable energy, although we cannot ultimately avoid the depletion of this kind of resources, we can prolong the service life for the development of new energy, especially renewable energy to create time conditions, and also reduce the environmental loads. Therefore, energy conservation is the preferred strategy for the development of circular economy.

China wall materials industry is the significant consumer of energy. The average consumption of unit product is much higher than the world advanced level, and the potential of the energy saving is huge. In the field of production, relying on scientific and technological progress and strengthening management will reduce half of the existing energy consumption level in a relatively short period of time. Taking the modern precalcining cement as an example, it can make the heat consumption of the cement clinker close to the theoretical heat consumption, only half of the cement wet kiln heat consumption. Energy saving is not only the strategy of the enterprise long-term development, but also has become a pressing matter of the moment of wall material enterprises.

3-3. Speed up and improve the legislation, establish and promote the development of circular economy laws and regulations and policy system.

Wall materials industry is an important industry in the national development of circular economy. The accelerating of the development needs the support of the national environment, including the laws and regulations of the state, economy, technology and environmental policy, industrial policy and standards and norms. In the process of practicing the development of circular economy, we must accelerate the formulation and improvement of relevant laws and regulations and policy systems, to make sure that there are laws and rules to abide by. I believe that in the near future, the state will continue to introduce a series of laws and regulations and policies promoting the development of circular economy.

In summary, the above composes of the theme the author discusses.

4. Drawing lessons from the development model of wall material industry in the developed countries

The western developed countries went through the industrial development for 200 years, and have reached a very high level in the use of resources and energy rate. In the pattern of circular economic development in many countries, building materials industry not only has achieved a steady and rapid development, and gradually created a new green industry, but also contributes more to the development of circular economy in the related industries, to speed up construction of a conservation-oriented society. All the countries in the world are committed to promoting the development of circular economy of the building materials industry, which basically has covered all aspects of the building materials, such as waste concrete, waste building plastic, waste waterproof roll, waste road asphalt concrete, waste plant fiber, waste bricks, industrial waste and other waste etc.

In the ASTMC-33-82 "concrete aggregate standard", the United States included the coarse aggregate in the broken hydraulic cement concrete. The CYCLEAN company of the United States of America uses microwave technology, and the recovery can be 100% of the old concrete pavement materials with the same quality and fresh concrete pavement materials, and the cost can be reduced by 1/3. And at the same time, it saves costs of the trash pickup and the processing, greatly reducing the environmental pollution in the city.

Holland is the earliest one of the countries carrying out the research and application of recycled concrete. In the nineteen eighties, Holland made clear requirements on the production technology of recycled aggregate concrete using the specification, and points out that if the content of recycled aggregate in the weight of the aggregate is not more than 20%, then, the concrete production can be done completely according to the design and production of natural aggregate concrete preparation method.

In addition, the developed countries as Germany, Japan, and South Korea have to formulate relevant laws and regulations to supervise and manage the concrete.

5. Conclusion.

At present, although China's resources recycling research on the building materials has made breakthrough achievements, there are still technical and social identity issues. The development of wall materials industry should follow: the recycling of the material, the recycling of the general waste in the construction and the application of new building materials, and what’s more, it should be led by the government, to form the protection of building resources with the "top-down" manner.

References

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[2] Dong Mengchen. Civil engineering materials [M], Beijing: China electric power press, 2008

[3] Yang Changming, Zhang Juan. Recycling of the building material resources [J], Journal of Harbin Industry University, 2007, (6), 27-6

[4] Feng Zhijun. China's Circular Economy Forum [M], Beijing: People's publishing house, 2005