How to select the dust remover of the sand and stone aggregate production line correctly
Release date£º2018/5/25
For a long time, the dust problem has been plagued by dry sand production enterprises, and it will also harm workers' health. At the moment of ecological environmental protection and high quality development as the key point of sand and stone industry transformation and upgrading, dust control in sand and stone factories has become a big pain point. In recent years, dust control has become one of the important parts of green development of sand and stone industry.
A brief introduction to the production line of sand and gravel aggregate
Gravel aggregate production line is mainly divided into gravel production line and machine-made sand production line. The gravel production line is mainly composed of jaw crusher, cone crusher, impact crusher, vibrating screen and some conveying equipment. The machine sand production line is divided into a wet sand production line and a dry sand production line. The former is mainly composed of sand machine, vibrating screen, sand washing machine, sand suction machine, filter press, sewage treatment pool and a number of conveying equipment. The latter is made up of sand making machine, vibrating screen, wind separator, dust collector, hoist, fine powder tank and a number of conveying equipment.
Two. The main pollution source of the sand stone aggregate production line
The main pollution of sandstone aggregate production line is sewage sludge and dust. The main pollution of the lithotripsy field is the dust produced when the equipment works. The previous practice is generally to spray water and dust, and often produce a large amount of sewage and sludge. Because the dry process sand system is not used to the requirements of the sand and gravel aggregate, the dust can also be collected through the dust removal. The added value of stone phase and composition will also be different, even far exceeding the market economic value of aggregate. The main pollution of manufactured sand production line is sewage sludge and dry system dust. The sewage sludge produced by wet process system has greatly damaged the environment and has been phased out. The dry sand making system does not produce sewage sludge, but is collected and sent to the fine powder tank by the powder remover and the excess stone powder and equipment dust in the machine-made sand. This will also be invaluable because of the different added value of fine powders and ingredients.
Three. Selection of dust remover for crushed stone production line
The dust collecting points of sandstone aggregate yard mainly include Hubei crusher, cone crusher, impact crusher, sand making machine, vibrating screen and so on. In view of these dust spots. We can calculate the required air volume and the size and quantity of the dust remover according to the technical position of the dust point. The collected fines are sent to a fine powder tank after being collected by conveying equipment.
Four. Selection of dust remover for dry sand production line
The main points of the dry method sand system are sand making machines and vibrating screens. In view of the necessity of dust removal in dry sand making system, we specially designed a special equipment suitable for this system, that is, powder remover. The so-called "powder removal machine", which is known as the "energy saving dry powder removal system", includes several characteristics: "energy saving", "dry method" and "powder removal". This system can not only control the powder content in the machine-made sand, but also realize the dust control on the spot dust.
Five. The correct selection of the dust collector
The selection of dust collector is composed of air volume, total pressure, filtration area, filtration speed and cleaning method. Considering that the dust control system has only social effect and no economic effect to the owners, it will also increase the production cost of finished aggregate. Many manufacturers of dust catcher will do their best by changing the internal structure of the dust collector, reducing the cost of the dust collector, and winning the market through price advantage. Such a practice is very undesirable. Purchasing equipment should not compare the price blindly, but mainly the quality of the dust catching products. Dust removal is a system integration, one part of the bad will affect the normal operation of the whole system, we know that the source of dust, can also be well eliminated, to eliminate hidden dangers.
In recent years, bag type dust removal has become the development direction of particle collection technology. Bag type dust removal equipment will have a wider space for development. The Ministry of land and resources put forward the general goal of "realizing the standard of green mine by 2020 and the management of small mine enterprises according to the standard of green mine and mountain standard". If the rich think that the gravel aggregate should realize the green mine, we must make the dust removal and environmental protection work practical and specialized. Only in this way can we achieve healthy development. The future of the aggregate production industry will become better and better.
At the National Conference on ecological environment protection, Xi Jinping stressed the importance of resolutely fighting pollution control.
Release date£º2018/5/23
The National Conference on ecological environmental protection was held in Beijing from 18 to 19. Xi Jinping, general secretary of the CPC Central Committee, chairman of the CPC Central Committee and chairman of the Central Military Commission, attended the meeting and delivered an important speech. He stressed that we should consciously integrate the economic and social development with the construction of ecological civilization, give full play to the political advantages of the party's leadership and the socialist system in China, and make full use of the solid material basis accumulated in the 40 years of reform and opening up, and increase the efforts to promote the construction of ecological civilization and solve the ecological environment problems. We must resolutely crack down on pollution control and promote the construction of ecological civilization in China to a new level.
Li Keqiang, member of the Standing Committee of the Political Bureau of the CPC Central Committee and Premier of the State Council, spoke at the meeting. The Standing Committee of the Political Bureau of the Central Committee of the Communist Party of China, chairman Wang Yang of the CPPCC National Committee, the Standing Committee of the Political Bureau of the Central Committee of the Communist Party of China, Wang Huning, the Secretary of the Central Secretariat, the Standing Committee of the Political Bureau of the Central Committee of the Communist Party of China, and Zhao Leji, the Secretary of the Central Committee for the discipline of discipline, attended the meeting. Han Zheng, member of the Standing Committee of the Political Bureau of the CPC Central Committee and vice premier of the State Council, made a concluding speech.
In his speech, Xi Jinping stressed that the construction of ecological civilization is a fundamental plan for the sustainable development of the Chinese nation. The Chinese nation always respects nature and loves nature. The Chinese civilization, which has lasted for more than 5000 years, breeds abundant ecological culture. Ecological prosperity is civilized, and ecological decline is the decline of civilization. Since the eighteen Party of the party, we have carried out a series of fundamental, pioneering and long-term work to accelerate the construction of the top design and system system of ecological civilization, strengthen the construction of the rule of law, establish and implement the supervision system of the central environmental protection, vigorously promote green development, and carry out the three major lines of air, water and soil pollution prevention and control. It took the lead in issuing the country plan for the implementation of the 2030 sustainable development agenda in China, and implementing the national climate change plan (2014-2020 years) to promote the historic, turning and global changes of the ecological environment protection.
Xi Jinping pointed out that on the whole, the quality of our ecological environment has been improving continuously, and there has been a steady trend toward good, but the results are not stable. The construction of ecological civilization is in the key period of pressure superposition and heavy load. It has entered a hard period to provide more high-quality ecological products to meet the needs of the growing ecological environment of the people, and also to the window period of the conditions that have the ability to solve the outstanding problems of the ecological environment. China's economy has shifted from high speed growth stage to high quality development stage, and it needs to cross some conventional and unconventional barriers. We must clenched our teeth and climb over the slope to cross the ridge.
Xi Jinping stressed that the ecological environment is a major political issue related to the mission purpose of the party and a major social issue related to people's livelihood. The broad masses of the people eagerly look forward to accelerating the improvement of the quality of the ecological environment. We should actively respond to the people's thoughts, expectations and urgency, vigorously promote the construction of ecological civilization, provide more quality ecological products, and constantly meet the growing needs of the people.
Xi Jinping pointed out that in the new era, we must adhere to the following principles to promote the construction of ecological civilization.
One is to adhere to the harmonious symbiosis between man and nature, adhere to the principle of saving priority, protecting priority and natural recovery, protecting the ecological environment like the protection of the eyes, treating the ecological environment like life, making the beautiful scenery of natural ecology permanent, and natural with tranquility, harmony and beauty.
The two is the green mountain, the Jinshan Yinshan Mountain, to carry out the concept of innovation, coordination, green, open and shared, to accelerate the formation of the spatial pattern of saving resources and protecting the environment, the industrial structure, the mode of production and the way of life, and leave the time and space of the natural ecology to rest and rest.
Three is a good ecological environment is the most popular well-being of the people, adhere to the ecological benefits, ecological benefits, ecology for the people, focus on solving the serious environmental problems that damage the health of the masses, and constantly meet the growing needs of the people's growing beautiful ecological environment.
Four is the landscape forest land lake grass is the life community, should take overall consideration, the overall policy and the multi - measures to carry out the ecological civilization construction in all directions, all regions and the whole process.
The five is to use the most strict system to protect the ecological environment with the most strict rule of law, speed up the system innovation, strengthen the implementation of the system, and make the system a rigid and non touchable high pressure line.
The six is to conspire the construction of the global ecological civilization, participate in the global environmental governance, form a solution to the world environmental protection and sustainable development, and guide the international cooperation on climate change.
Xi Jinping stressed that we should speed up the construction of ecological civilization system, speed up the establishment and improvement of ecological culture system based on ecological values, the ecological economy system based on industrial ecology and ecological industrialization, and the goal responsibility system with the improvement of the quality of the ecological environment as the core, and the modernization of the governance system and the governance capacity. The system of ecological civilization guaranteed is an ecological security system focusing on the benign cycle of ecosystem and effective prevention and control of environmental risks. We must accelerate the construction of an ecological civilization system and ensure that the goal of beautiful China will be basically achieved by the end of 2035. By the middle of this century, material civilization, political civilization, spiritual civilization, social civilization and ecological civilization have been promoted in an all-round way. The green development mode and way of life have been formed in an all-round way. The harmonious symbiosis between man and nature, the modernization of the national governance system and governance ability in the field of ecological environment have been fully realized, and a beautiful China has been built.
Xi Jinping pointed out that the green development should be promoted in an all-round way. Green development is an inevitable requirement for building a high-quality modern economic system and a fundamental solution to the problem of pollution. The key is to adjust the economic structure and energy structure, optimize the layout and adjustment area of land development.
Cement industry has broad prospects for transformation to aggregate industry.
Release date£º2018/5/23
At present, more and more cement enterprises have begun to think about how to continue to develop, and even some backward enterprises have the willingness to withdraw voluntarily, as the country's policies on cement industry are gradually introduced and the cement industry is becoming more and more saturated. The cement industry is faced with the following problems:
1. Restrictions on national regulations and environmental policies. In recent years, various policies have been put forward to rectify the cement industry and eliminate cement enterprises with serious pollution and backward production capacity.
2, overcapacity. Cement production capacity growth is far greater than the growth rate of cement market demand, cement overcapacity is a foregone conclusion.
3, the profit is too low. The development of cement enterprise group has a large investment and less income, and the loss enterprises in the cement industry are increasing, and most of the enterprises are in the state of low profit or no profit production and operation.
At the same time, more and more cement enterprises have begun to extend to the related industrial chain, and build sand and stone aggregate production line in cement enterprises to improve the production technology level, accelerate the supporting waste heat generation projects, strengthen production management and reduce production costs.
Sandstone aggregate is a very open market, and cement enterprises have inherent advantages. Cement enterprises enter the gravel aggregate industry not only is the trend of the times, but also has huge market space and competitive advantage, and the prospect is very broad.
1, state policy support. The government has issued a policy of restricting natural sand and gravel management to promote the production of artificial aggregate. At present, the state has also introduced fiscal policy to encourage the development and utilization of recycled aggregate concrete and provide tax incentives.
2, the market demand is large. All infrastructure projects, such as railways, highways, bridges, houses, and so on, all need to use gravel aggregate. Rigid demand determines the huge potential of the sand Market.
3, the profit margin is wide. According to the calculation of 3-4 cubic meters of concrete per ton of cement (the strength grade of concrete is C30), the amount of sand and stone per cubic meter of concrete is about 1800 kilograms. It is estimated that the annual output of 18 million tons of cement can be allocated to 54-72 billion cubic meters of concrete, and the amount of sand and gravel required will be as high as 97.2-129.6 million tons. According to 40 yuan per ton of sand and gravel, the output value is about 3888-5184 billion yuan, which is equivalent to the output value of cement industry.
4. The advantages of the cement plant. The cement plant has its own mine resources, mastered advanced ore mining technology, has experienced talents and mature equipment. It also occupies the advantage of abundant capital and strong competitiveness. The mine in the clinker base can be equipped with perfect sand and gravel production facilities gradually, with low cost and good income, in order to realize the scale benefit. And the effect of the extension of the industrial chain.
5, from the environmental protection point of view, sand and gravel industry for the production of sewage produced in the mining, environmental treatment requirements are very high, simple sand aggregate production enterprises may be difficult to reach, so that it is called to stop. Cement enterprises have their own advantages in the cement kiln joint treatment of sewage, and will not be affected.
How do cement enterprises develop sand and stone aggregate industry? Xu Yongmo, President of China Building Materials Federation and President of China concrete and cement products association, suggested the development of "cement sand concrete". Cement enterprises enter the aggregate market, not to make sand and gravel. In the case of serious excess capacity overcapacity in the future, entering the concrete industry is a change choice, and the sand and gravel industry must enter the concrete industry at the same time, so through the development of "cement sand concrete" integration to form the final competitive advantage of the cost and brand.
Sand and aggregate must be modernized and modern industrial technology and equipment must be introduced. The homogenization concept is introduced to solve the problem of sand grading, clay content and moisture content. Enterprises also need to develop or select advanced technology and equipment, reduce the needle like aggregate, improve the roundness of aggregate and reduce the porosity of aggregate accumulation, thus reducing the amount of cement slurry and reducing the cost of concrete.
Technical innovation of environmental equipment enterprises in China needs to be strengthened
Release date£º2018/5/23
In the legal system of our country, the technical standard of industry and product is not included. The existing technical standard system is confused and the technical standard is too low. It is not suitable for the fair competition in the domestic market, and it is difficult to support the products to open up the international market. This leads to the lack and backwardness of the legal environment, resulting in enterprises not paying enough attention to the mandatory and rigid role of technical standards. Most enterprises do not understand the technical standards and the fine requirements of the product technology in the legal system of developed countries, do not understand the technical restrictions of the importing countries, and have a huge negative effect on the short term interests in the operation. There is a huge gap between China and the international standard system, which directly causes the low competitiveness of our products, and there are great differences and incomparability with the quality, specification, cost and environmental protection index of foreign products.
In addition, the technology of our enterprises is hard, the automation rate is low, the quality management level is not high, and the products are hard to meet the technical standards of developed countries. If the solar vacuum collector glass tube is required to be smooth, uniform and high permeable, and the enterprises in our country are limited by the technical level of production technology, glass furnace and workers, there are many gas line bubbles on the drawn glass tube, which does not conform to the quality requirements of the importing country. In China, the heat glass tube industry has developed for more than 20 years since the beginning of 80s. At present, there is no one state and perfect authoritative detection institution, and the inspection institution set up by local provinces and cities is still used in the country in 70s and 80s. It is difficult to achieve the accuracy and credibility of the data.
The environmental protection equipment enterprise is a high-tech enterprise with the technology innovation and business model innovation, its innovative technology represents the international advanced technology level, has a certain international competitive advantage, and belongs to the national strategic new industry. The production of environmental protection regeneration equipment is used in the circuit board enterprise's cleaner production equipment system. The innovative business model is to provide unpaid circuit board production enterprises with their own production of environmental protection equipment, to install and provide technical support, and the ownership of the equipment has not been transferred. The recovered copper is shared by environmental protection equipment enterprises and circuit board enterprises. PCB manufacturers are zero investment, zero financial risk and high return. Compared with the old model, PCB not only shares the income benefit of copper recovery, but also saves a huge amount of water cost and water cost, and achieves the sharing of high tech results and profit, and achieves the multi win of economic and social benefits.
However, according to the point of view of the local environmental protection bureau and the administrative punishment behavior, after the installation of environmental protection equipment to the circuit board production enterprise, the complex and time-consuming environmental impact assessment report is required to be approved, which brings huge trouble and time cost to the circuit board enterprise, thus blocking the market potential of the innovative technology and causing the failure to operate. Go.
Analysis of future market for disposal of hazardous waste by cement kiln
Release date£º2018/5/23
Hazardous waste refers to the inclusion of the national directory of national hazardous wastes or the state identified as a waste of toxic, corrosive, flammable, reactive, or infectious in accordance with a certain technical standard. In the 2016 edition of the national hazardous waste list, the list of hazardous wastes is divided into 46 categories, which are divided into 479 kinds. According to the different sources, they can be divided into industrial hazardous waste, medical waste and other hazardous wastes. At present, the leading industries of the dangerous industries are Dongjiang environmental protection, Veolia China, Everbright International and so on. As the disposal of hazardous wastes in cement kiln has the advantages of congenital technology and cost, the disposal of hazardous waste by cement rotary kiln has been paid more and more attention by technical workers. Since this year, it has been showing an explosive growth trend.
1. The advantages and problems of the disposal of cement kiln:
The disposal of cement kiln and professional high temperature incinerator can realize the reduction, harmless and resource utilization of hazardous waste, but the synergistic disposal of cement kiln has more advantages: (1) high temperature (1800 C) and 5-15s residence time in cement kiln can effectively reduce the production of dioxin; (2) the fly ash and slag can be made into the production of cement clinker. Zero discharge; (3) the medium scale professional incinerator can handle the hazardous waste 60t daily, while the minimum scale cement kiln synergistic disposal equipment (the related production line capacity 2500t/d) can reach 100t for the daily critical waste treatment. (4) according to the calculation, the construction of a professional incinerator with 10 thousand tons of hazardous waste disposal should cost 40 million yuan and the same processing capacity. The cooperative disposal equipment for cement kiln is only 1/4-1/5. (5) the cost of disposing hazardous waste in the cement kiln is 2000-2500 yuan per ton, and the professional incinerator is 3000-3500 yuan / ton compared with the professional incinerator, and the operation cost is lower.
Hazardous waste treatment needs corresponding qualification, high technical requirements, and trade barriers are relatively higher than other environmental protection industries. Small and medium-sized enterprises with relatively limited capital and technology are more difficult to obtain appropriate qualifications to enter the hazardous waste disposal industry. The waste disposal project needs a long period from the declaration to the qualification and the operation. Generally, it is at least three years. Because of the long investment cycle, the capital strength of the enterprise is high. With the further regulation of the hazardous waste market, private enterprises and state-owned enterprises with strong capital and strong technological strength will benefit from the process of market standardization.
2. What is the future market and the profit model?
The output of hazardous waste is huge, showing a trend of growth in recent years, and the actual output is far greater than the market statistics. According to the official statistics, the production of hazardous waste in China reached 39 million 760 thousand tons in 2015. At present, the annual output is estimated to be over 50 million tons. The output of hazardous waste is expected to reach 60 million tons by 2020, and the actual production will be more. According to the average processing price of 3000 yuan / ton, it is expected to exceed 200 billion yuan in 2020.
The operation mode of cement kiln to dispose of hazardous waste in collaboration with cement kiln:
A. dispersion joint operation mode means that when the cement production enterprise and the hazardous waste pretreatment center belong to different legal body, the hazardous waste is transported to the cement production enterprise and directly into the kiln after the pretreatment center is pretreated to meet the requirements of the kiln (grinding). The operating mode of cooperative disposal.
B. decentralized operation mode means that the cement production enterprise and the hazardous waste pretreatment center belong to the same legal person, and the hazardous waste is transported to the cement production enterprise and directly into the kiln after the pretreatment center is pretreated to meet the requirements of the kiln (grinding). The management mode of the same disposal.
C. centralized management mode refers to the operation mode of preprocessing and cooperative disposal of hazardous waste in the factory area of cement production enterprises, including hazardous waste pretreatment and cement kiln co disposal facilities or operation belonging to the same legal person or the subject of different legal persons. Administration¡£ The healthy development of the industry can not be separated from the orderly management system. "One certificate management" will force the "scattered pollution" enterprises that fail to meet the environmental standards to be eliminated.
According to the technical policy for the prevention and control of solid waste pollution by the cement kiln in December 2016, "after the release of this technical policy, the cement enterprises to build, rebuild or expand the disposal of hazardous waste should choose a single line design of 4000 tons / day of clinker production and the cement kiln." By the end of 2016, there were 628 4000t/d in the country, 114 in 4000t/d and 742 in total. If all the cement kilns were disposed in accordance with the scale of 300t/d, the annual capacity could exceed 80 million tons, covering about 80% of the annual output of hazardous waste. However, the cement kiln is not specially set up for the disposal of hazardous waste, but still mainly to produce cement, which requires basic cement demand, otherwise the enterprise library will have to stop the kiln. Therefore, enterprises with serious excess capacity should be considered comprehensively. Considering the serious overcapacity factors in some areas and the requirements of site selection, the cement enterprises that are really suitable for the disposal of hazardous wastes may be less than 50% of them (<370). Even so, the cement kiln is still expected to be able to occupy a place because of the advantages of innate technology and cost, such as the disposal of hazardous waste in cement kiln.
How does the United Company continue to establish a social grinding station?
Release date£º2018/5/23
At present, more and more cement joint companies have been set up in China, and the joint companies are formed jointly by large local groups. Although there are clouds in the industry, it is beneficial to the production capacity of cement in the region, the transformation and upgrading of the industry, and the role of regional price preservation, but it is also full of "joint lifting of prices" from the beginning. Criticisms.
Since then, the "tacit understanding" between large conglomerates is more complete. This is also a greater worry for the social grinding station.
Grinding station is a necessary part of grinding clinker into the final product cement. In general, it has many advantages, such as near the market, convenient traffic, flexible body volume and so on. The number of cement grinding stations accounted for 63.8% of the total number of cement enterprises, and the proportion of grinding stations owned by ten enterprises before the clinker production accounted for only 12.22% of the number of national grinding stations, that is, the mass of the social grinding station.
The external sales volume of large cement group generally only accounts for 5%~30% of its output, and the proportion is not high. At the beginning of last year, domestic clinker, especially the region along the river, began to enter the time of control sale, while foreign clinker entered the river market in our country, but it was hit by price, and the confidence of the market was difficult to pick up.
At present, the impact of clinker impact at home and abroad is not very big. At present, the clinker in our country is about 400-410 yuan / ton, but the price of Vietnamese clinker boat is 360-370 yuan per ton after the Vietnam clinker. In particular, the joint venture established by regional big enterprises will make the clinker control sale more obvious. It is not surprising that clinker is the forerunner of cement price and price upside down.
At the same time, most social grinding stations are faced with many problems, such as serious clinker control, strict environmental inspection, high cost of production, and even some of the reasons that are in the stage of stopping production because of environmental protection and no clinker. In the situation of the structural reform of the supply side and the entry into the deepwater area, partial grinding is made. The future of the station will be faced with transformation and upgrading, industrial chain extension or directly withdrawing from the market.
If there is a definite loss, then a loss reduction is earned. That is to say, finding a way out as early as possible is bright. So it is very appropriate to describe the current situation of the grinding station.
Since 13th Five-Year, large-scale infrastructure construction has led to a huge demand for cement. Because of flexible investment in grinding stations and no need for capacity replacement, a new production line can be built, so the quantity has sprung up like bamboo shoots after the rain. In the period of no peak production limit, the grinding station still has a certain profit space. With the time of peak production and the further expansion of space in recent years, the market supply is tense, the large enterprise groups reduce the clinker export, and the difficulty of the grinding station becomes more difficult.
On the one hand, the state unify the 32.5R strength grade of the composite Portland cement (PC32.5R), the production cost of the grinding station is increased; on the other hand, if there are excessive standards in the production process, the environmental protection exceeding the standard penalty, the energy consumption exceeding the standard, and the implementation of the step electricity price measures are further added to the production pressure of the enterprise.
The national development and Reform Commission issued the guidance list of industrial restructuring (2011 Edition), which clearly stated that the cement grinding station under 600 thousand tons / year is a restricted category. According to many research and suggestions from the relevant industry, enterprises should make serious decisions and think. At present, the 600 thousand tons / years of grinding stations, such as 300 thousand tons / year, should withdraw from the market as soon as possible, and the enterprises in the limits or above can withdraw from the market or carry on the transformation in combination with their own circumstances.
Turning to the localities, some local governments will be more strict with environmental protection supervision, and only a few places need to fulfill their duty to pay taxes. For grinding station, it is essential to make a scientific judgement for the future of the enterprise ahead of time.
Objectively speaking, grinding station has its advantages and necessity. If the enterprises continue to produce, they need to meet the standards of environmental protection and energy consumption, and the enterprises can control themselves according to the environmental impact assessment book. However, enterprises that fail to meet the standards are facing the dilemma of shutting down.
If we continue to produce, on the one hand, we need to work on the supply of raw materials, through the establishment of cooperative relations with large enterprise groups, clinker enterprises, and third party e-commerce platforms (such as equity cooperation, capital cooperation, direct business cooperation, etc.), and the developed areas can also strengthen the purchase of imported clinker; the other is the other party. It needs further transformation and upgrading or industrial chain extension to reduce production costs and enhance profit margins. Under the circumstances of environmental protection and energy consumption reaching the standard, technical transformation and energy saving transformation should be carried out to reduce costs. It may also be transformed into concrete services to make dry mixed mortar and concrete admixture to provide premixed materials for concrete prefabricated parts and functional cement components.
For those enterprises that do not carry out production after comprehensive consideration, they should plan ahead, seek reorganization or conduct cross industry transformation in the direction of industrial tourism and hotels.
Return to the cement industry, not only the grinding station, all energy cement enterprises in environmental protection, energy consumption standards will be more stringent, when the future cement demand is not in the high platform period, some backward production capacity and no core competitiveness, will enter the social grinding station similar embarrassment.
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