Solid waste treatment, the full name of solid waste treatment, usually refers to the physical, chemical, biological, physicochemical and biochemical methods to convert solid waste into suitable for transportation, storage, use or disposal of the process, solid waste treatment is harmless, reduction, resource recovery.
China's energy conservation and environmental protection industry ranks first among strategic emerging industries, with strong policy support. It is estimated that during the 12th five-year plan period, investment in the environmental protection industry will reach 3.1 trillion yuan. Key investment projects in environmental protection involve solid waste treatment, desulfurization and denitrification, municipal sewage, sludge, industrial wastewater and other aspects.In addition, the general office of the ministry of industry and information technology issued the implementation of industrial solid waste comprehensive utilization of notice of the pilot base construction, points out that by the end of the 12th five-year, industrial solid waste comprehensive utilization will be in the pilot regions on the basis of 10-12% in 2010, the construction of a number of different characteristics of industrial solid waste comprehensive utilization of base, forming a set of perfect system of comprehensive utilization of industrial solid waste policy and promotion mechanism, promote the comprehensive utilization of industrial solid waste leap-forward development.Solid waste treatment industry in China is faced with good industrial development opportunities.
The proportion of investment in solid waste treatment in China's environmental protection investment is at a low level for a long time, which leads to a serious shortage of solid waste treatment and disposal facilities. "the 12th five-year plan" will be an inflection point for the investment level of solid waste treatment industry from low to high, and it will enter the construction peak in the next five years.During the eleventh five-year plan period, the total investment in the construction of facilities for harmless disposal of domestic garbage nationwide was 86.29 billion yuan, with an average annual investment of 17.3 billion yuan.The total investment in solid waste treatment, including medical waste and industrial waste, is about 210 billion yuan, with an average annual growth rate of 18.5%. Among them, the growth rate of solid waste treatment is 25%, which ranks first in environmental protection investment.
During the 12th five-year plan period, China's solid waste treatment industry will enter a period of rapid development.In the next five years, the investment in China's solid waste treatment industry will reach 800 billion yuan, accounting for 25.8% of the total investment of 3.1 trillion yuan in the environmental protection industry. The compound annual growth rate is about 30%, which is twice the growth rate of the overall investment in the environmental protection industry.Under the promotion of policy, China's solid waste treatment field will usher in more optimistic growth space.The "twelfth five-year plan" for heavy metal pollution control has been approved by the State Council. The 60 billion yuan invested in the "twelfth five-year plan" for heavy metal pollution control in the Xiangjiang river basin is spent on recycling waste products.Driven by these policies or industrial planning, solid waste disposal projects, equipment and solid waste facility operations, and other sub-industries will enter a period of rapid growth.Among them, solid waste engineering equipment business will benefit first, and professional operators will also usher in greater development opportunities.
Some people think that is the most difficult of "three wastes" disposal of solid waste, because it contains the ingredient is very complex, its physical properties (volume, liquidity, uniformity, crushing degree, moisture content, calorific value, etc.) also, to achieve the above "harmless, reduction and recycling" will have considerable trouble, general method for solid waste pollution prevention and control is to control the quantity first, for example, the gradual reform of the urban fuel structure, including civilian industry control plant raw material consumption, norm to extend the service life of products, improve the waste recovery, etc.;The second is to carry out comprehensive utilization, solid waste as a resource and energy treatment, really can not be used after compression and non-toxic treatment into the final state of solid waste, and then landfill and sink into the sea, the main methods used at present include compaction, crushing, sorting, curing, incineration, biological treatment and so on.
Compaction Technology
Compaction is a kind of based on waste to change capacity reduction, to reduce transport costs, extend the service life of the landfill, the preprocessing technologies, compaction is a kind of widely used solid waste pretreatment method, such as cars, such as cans, plastic bottles usually first USES the compaction process, suitable for compaction to reduce volume processing of solid wastes, unfavorable use compaction process, some may cause operational problems of waste, such as tar, sludge or liquid materials, generally unfavorable also make processing of compaction.
Crushing Technology
In order to reduce the appearance of wastes entering incinerators, landfills, composting systems and other wastes, solid wastes must be crushed in advance. Due to the elimination of large gaps, the crushed wastes are not only uniform in size but also uniform in texture, so they are compacted in the landfill process.There are many crushing methods of solid waste, including impact crushing, shear crushing, extrusion crushing and friction crushing.The most widely used and most effective solid waste crusher is the shear crusher. For landfill and compost waste, the spiral roller crusher is more effective.
Separation Technology
Solid waste separation is an important means to realize resource utilization and reduction of solid waste.The other is to separate the wastes of different particle sizes. The basic principle of sorting is to separate the wastes by taking advantage of the differences in some aspects of the materials.For example, the use of magnetic and non-magnetic differences in waste separation;The particle size difference was used for separation.Specific gravity difference is used for separation.According to different properties, various machines can be designed and manufactured for sorting solid waste, including manual sorting, screening, gravity sorting, magnetic sorting, eddy current sorting, optical sorting and so on.
Curing Technology
Curing technology is added to the waste curing base material, make the hazardous solid waste fixed or inclusion in the base material of a kind of harmless handling inert curing process, after processing of curing product should have good permeability resistance, good mechanical and leaching resistance, resistance to wet, freezing-thawing resisting property, curing processing according to different curing base material can be divided into the sink the solidification, asphalt solidification, glass curing glue, curing, etc.
Incineration And Pyrolysis Technology
Incineration is a comprehensive treatment process of high temperature decomposition and deep oxidation of solid waste.Due to solid waste of fuel, gradually increase the proportion of the solid waste incineration method processing, has become a developing trend, must use its heat treatment method, this kind of solid waste, covering an area of less, large capacity, in the protection of the environment, incinerators in big cities, more than 100000 people, and is equipped with energy recovery system.Due to the shortage of land in Japan, incineration method is gradually adopted. The heat energy obtained in the incineration process can be used to generate electricity, and the heat produced by the incinerator can be used to heat residents and maintain the greenhouse temperature.Japan and Switzerland currently burn more than 65% of their urban waste every year to make energy.However, the incineration method also has some disadvantages, such as large investment, secondary pollution caused by smoke exhaust in the incineration process, and serious corrosion of equipment.Pyrolysis is the decomposition of organic matter into gas, liquid and solid products by heating it at high temperature (1000 ° c-1200 ° c) in the absence of oxygen or hypoxia. Compared with incineration, pyrolysis is a more promising treatment method. Its most significant advantage is that it has less capital investment and the gas generated after pyrolysis can be used as fuel.
Bioprocessing Technology
Biological treatment technology is the use of microbial decomposition of organic solid waste to make it harmless to the transformation of organic solid waste to energy, food, feed and fertilizer, can also be used to extract metals from waste and waste residue, is an effective technology for curing waste recycling method, the more widely used are: sugar, composting, biogas, waste cellulose waste fiber production of feed, biological leaching, etc.
