Industry news

Hazardous wastes can be divided into 46 categories and 479 kinds. The 2016 edition of the list of hazardous wastes optimizes and reduces the major categories, but refines the sub categories, which is more in line with the actual situation of industrial production and increases the enforceability. The original list of 49 categories of 400 kinds of hazardous wastes was adjusted to 46 categories of 479 kinds, and the new 79 kinds were mainly the refinement of hw01 medical waste, hw11 distillation residue and hw50 waste catalyst waste.

Hazardous waste mainly includes industrial waste, municipal waste and medical waste. Among them, industrial wastes account for more than 70% and medical wastes account for about 14%; among the industrial hazardous wastes, waste acid and alkali account for 30%, asbestos waste 14%, and non-ferrous metal smelting waste 10%; among the source industries, chemical raw material and product manufacturing account for 19%, non-ferrous metal smelting 15%, waste metal mining 14%, and paper industry 13%.

Technology overview 1. Hazardous waste treatment methods: the basic treatment steps of hazardous waste include classification, pretreatment and final disposal. Metals, oils, solvents, dyes and other wastes with recycling value can be used as resources; pretreatment includes physical and chemical methods, and hazardous wastes after pretreatment can be put into final disposal facilities such as incineration or landfill.

In China, the treatment of hazardous waste is mainly harmless treatment and resource utilization. The mode of resource utilization is that hazardous waste resource enterprises collect valuable waste from upstream waste production enterprises, and then purify and produce resource products. The income comes from the sales of products, and the profit is affected by the price of upstream waste and downstream metal. Harmless disposal means that the disposal enterprises collect fees from the waste enterprises, mainly including incineration, landfill and physicochemical treatment. The collaborative disposal of cement kiln can also be listed as the method of harmless disposal. The gross profit of innocuity is high. The gross profit of incineration is more than 40%, and that of landfill is more than 50%. The marginal disposal cost of cement kiln and cement kiln is lower.

2. Harmless incineration

Innocuity accounts for 36.3%, and it is expected to increase to 38.5% in 2020. In 2016, the total amount of industrial hazardous waste disposal was 44.3 million tons, including 28.24 million tons of resource disposal and 16.06 million tons of harmless disposal, of which 36.3% was harmless disposal. We expect that the proportion of harmless waste will continue to increase: for industrial enterprises, recycling waste is profitable, and enterprises have the power to deal with such waste; while hazardous waste without resource utilization value that should be disposed of innocuously may be illegally discharged. With the tightening of supervision, this part of hazardous waste is an incremental demand. Incineration project is the main incremental capacity in innocuity. Incineration and landfill are the main methods for the final disposal of hazardous wastes. The fly ash and some physicochemical products from incineration also need to be landfilled. The landfill capacity is in short supply. At present, most of the wastes sent to landfill are incineration fly ash, heavy metal sludge and other wastes that can not be reduced continuously. However, the development of landfill is limited by the factors of land occupation, disposal types and project approval. The phenomenon of "waste besieged city" in eastern and central cities is serious. The location of landfill site and the accumulation and storage of industrial waste are big problems. In order to expand the city and save land, the government departments will be very cautious about a single landfill project. And incineration can be greatly reduced to 5%, more land saving, more suitable for China's national conditions. According to the survey results, hazardous waste incineration projects in Guangdong, Shanghai and other places are in full production, and the demand for incineration is very strong. The increase of hazardous waste harmless production capacity mainly comes from incineration project, and the collaborative disposal of cement kiln is the supplement.

3. Application of new technology the research on new technology of hazardous waste incineration is carried out simultaneously with the project construction. The technologies that are expected to be popularized in a large range include pyrolysis gasification, molten salt technology, electric reactor and plasma system, etc. Pyrolysis and incineration: pyrolysis needs higher temperature, and the fuel in the furnace is oxidized to release heat, or the waste is decomposed and gasified by external heat source such as heat exchanger. The vertical rotary pyrolysis gasification incinerator was listed as the promotion technology in the catalogue of major environmental protection technology and equipment (2017 Edition) released by the Ministry of industry and information technology in November; plasma: using the high-temperature thermal plasma generated by the plasma torch to instantly add a large amount of energy into the waste, the high-temperature pyrolysis is complete, the amount of tail gas is reduced and clean, and the slag can be made into glass body and solidified Metal, etc. The third incineration production line of the solid waste disposal center operated by Shanghai environment adopts advanced plasma gasification and melting system. The treatment scale of the facility is 30 tons / day. The exhaust emission parameters such as SO2, NOx, HCl, particulate matter, dioxin, etc. meet the European Union 2000 standard, and the direct operation cost is less than 2000 yuan / ton. It passed the system acceptance of Shanghai Science and Technology Commission in May 17. But generally speaking, for hazardous waste incineration, the rapid increase of production capacity is the first priority. More is the upgrading and improvement of the existing technology, such as how to reduce the comprehensive investment cost, how to reduce the energy consumption and other operating costs, how to better control the exhaust emissions, etc.

4. Collaborative disposal of hazardous waste in cement kiln collaborative disposal of hazardous waste in cement kiln refers to the process of putting hazardous waste that meets or meets the kiln (mill) requirements after pretreatment into cement kiln or cement mill to realize the harmless disposal of hazardous waste while producing clinker or cement. Cement kiln can not only dispose of hazardous waste, but also dispose of municipal waste such as domestic garbage. It has been more than 40 years since the United States, Europe, Japan and other developed countries used cement kilns to treat solid and hazardous wastes, and the technology is mature. The advantages of cement kiln collaborative disposal are as follows: 1) in terms of site selection, it is only necessary to select the suitable one from the cement kiln without re site selection, which saves a lot of preliminary time, and the overall approval is about one year faster than the new incineration project; 2) the transformation cost is low and the transformation time is short. The investment of new incineration project is about 4000 yuan / ton, the cost of cement kiln collaborative transformation is only 1500 yuan / ton, and the transformation period is about 6-8 months, which is more than one year faster than the construction of incineration project; 3) the operation cost is low, the hazardous waste can be used as fuel, and there is no waste residue to be treated, which saves a lot of processing cost; 4) considerable disposal fee income is brought.

Technical aspects: 1) high temperature, ordinary hazardous waste incinerator 800-900 degrees, and cement rotary kiln material temperature as high as 1450 degrees, under this high temperature, general organic matter incineration removal rate as high as 99.99%; 2) long time, rotary kiln barrel is long, full combustion; 3) acid gas is neutralized into stable salts in alkaline environment of cement kiln; 4) waste residue does not need subsequent treatment such as landfill.

Hazardous wastes can be divided into 46 categories and 479 kinds. The 2016 edition of the list of hazardous wastes optimizes and reduces the major categories, but refines the sub categories, which is more in line with the actual situation of industrial production and increases the enforceability. The original list of 49 categories of 400 kinds of hazardous wastes was adjusted to 46 categories of 479 kinds, and the new 79 kinds were mainly the refinement of hw01 medical waste, hw11 distillation residue and hw50 waste catalyst waste.

Hazardous waste mainly includes industrial waste, municipal waste and medical waste. Among them, industrial wastes account for more than 70% and medical wastes account for about 14%; among the industrial hazardous wastes, waste acid and alkali account for 30%, asbestos waste 14%, and non-ferrous metal smelting waste 10%; among the source industries, chemical raw material and product manufacturing account for 19%, non-ferrous metal smelting 15%, waste metal mining 14%, and paper industry 13%.