Analysis on the problems existing in domestic wast

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Analysis on the problems existing in domestic waste incineration power generation and the development of new technologies

waste incineration power generation is one of the most important ways to effectively treat waste at home and abroad, but direct incineration of waste is easy to cause harm to the environment. Convert the urban domestic waste that has not been classified into high calorific value renewable new energy fuels, and build a demonstration production project of incineration and efficient power generation to form clean electric energy. The flue gas purification treatment makes the emission of dioxin and other flue gases better than the limit requirements of national standards and European Union standards. Its power generation capacity per ton of waste reaches about 1100k w h, which is 2-3 times that of domestic waste to energy power plants, Realize the real purpose of garbage "harmless", "resourceful", "beneficial" and "industrialized" utilization

1 principle of waste incineration power generation

waste incineration refers to the process in which toxic and harmful substances in waste are fully pyrolyzed at the temperature of 850 ° c-1000 ° C, the high-temperature gas produced is purified through the use of purification and dust removal equipment, part of the heat is recovered, and a large amount of hot steam generated is converted into electric energy through a hot steam generator. After incineration, the weight of waste is reduced by 70% and the volume is reduced by 80%-90%. Therefore, in order to achieve the effect of weight and volume reduction, the waste can be incinerated to completely eliminate the bacteria. The advantages of waste incineration are that it generates electricity by heating, occupies a small area, and uses waste residue as building materials

2 application of waste incinerator technology

according to different incineration principles, the application of urban waste incineration power generation technology in China mainly includes the following aspects:

2.1 incineration technology of pyrolysis furnace. By isolating air, fully decomposing organic substances in garbage and using NaOH lye to purify hot steam are the service conditions for pyrolysis furnace incineration. At present, this is an advanced method. The furnace has a very simple structure. Compared with the cost of the grate furnace, the cost ratio of the equipment will be nearly 50%, which has a relatively small treatment capacity. The waste residue after combustion has a very high carbon content, which is the disadvantage of the pyrolysis furnace. Because it is not suitable for cities with extremely high domestic waste output every day, it can not be widely used

2.2 incineration technology of grate furnace. The waste incineration power generation in large cities in China is the same as the waste incineration treatment and disposal in many developed countries. The grate furnace incineration technology is the main technology. The technical principle is as follows: firstly, the domestic garbage is transported to the garbage pool. After the garbage has been fermented for more than 7 days, the garbage is grabbed into the hopper by the garbage crane, and enters the grate through the pusher. The grate mechanically moves back and forth, and is evenly spread on the grates at all levels (when the furnace temperature is lower than 850 ℃, the fuel oil or gas needs to be used as the auxiliary fuel), and then a large amount of high-temperature air is added for combustion support, Finally, the garbage will be fully burned. The advantages of grate furnace incineration technology are: the annual operation time of the equipment is up to 8000 h, so this is a very mature technology. Compared with other methods, the waste treatment cost is low, and there is no need to add fuel during normal operation, so it can be widely used to treat all kinds of domestic waste. The disadvantage is that it has higher equipment price and maintenance price, and the incineration efficiency is lower than that of fluidized bed incineration. The flue gas temperature is high. In order to improve the desulfurization efficiency of flue gas, SDA system is generally required to reasonably cool the flue gas

2.3 fluidized bed incineration technology. This technology is definitely recommended by China's energy conservation and environmental protection technology. The operating principle of fluidized bed incineration technology is: lay a lot of slag or sand inside the working furnace, and raise the temperature in the furnace to above 60o ℃. After classification and other steps, the crushed domestic waste is put into the combustion furnace. At the same time, the pulverized coal and slag with a ratio of less than 20% are burned and agitated. The sand in the boiling state in the furnace has excellent heat conduction effect and can quickly burn the waste. The sand can be used circularly. Compared with the grate furnace, the continuous operation capacity is poor. Generally, the boiler needs to be shut down for maintenance once a month. In addition, low sulfur coal needs to be added to the garbage as auxiliary fuel

3 development status and existing problems of domestic waste incineration power generation

development status of domestic waste incineration power generation. Because the waste incineration technology has significant reduction and high treatment efficiency. 2. When using and handling the pressure testing machine, it is easier to choose the site, and the waste heat can be recovered, which can completely achieve harmlessness. In recent years, domestic waste incineration technology has developed rapidly, and the investment, operation and management are more standardized. Through the summary of the development process of China's waste incineration power generation industry, it has the following characteristics:

1) it has increasingly sound policies and regulations. In order to promote the development of waste incineration power generation technology, in recent years, China's relevant departments have formulated and issued a series of power generation policies and measures

2) is the rapid development of technology. Although it started late, the domestic waste incineration technology in China has achieved leapfrog development and developed rapidly, realizing the localization of waste incinerator equipment, so as to better promote the promotion and application of waste incineration power generation technology. At present, China's waste incineration power generation technology has basically reached the international advanced level after years of development and improvement

3) some key equipment still need to be imported, such as hydraulic system, grate, rotary atomizer, high-precision control system, etc., which are used around graphene in digital economy related fields such as sensors and touch screens. The equipment needs a higher investment. There is a waste investment of about 400000 yuan per ton of waste per day. At present, a large part of the urban economy in China can not afford it

4) it is difficult to locate and land garbage power plants. Recently, the government has increased publicity on this issue, but at this stage, the domestic science popularization on waste incineration power generation needs to be further strengthened. In addition to the illegal emissions of individual enterprises in previous years, some media exaggerated their reports, and people were generally anxious. One side is that the garbage power plant should be built, and the other side is that it should not be built at my door. On the one hand, the amount of garbage is increasing year by year, and on the other hand, the processing capacity is still dwarfed. How to deal with garbage? The government departments are in a dilemma, the surrounding people are anxious, and the waste treatment project is in a dilemma. Everyone makes garbage, everyone hates garbage, and the construction of garbage treatment facilities is a recognized problem. However, there is no choice. There is always a gap between the increasing waste production and the actual treatment capacity. Garbage is produced all the time. If the "treatment" can not beat the "production" speed, garbage will be in the city. If the treatment quality is lower than the scientific standards and public expectations, it will cause environmental pollution, health damage, and even hurt the people

4 suggestions on improving municipal waste incineration power generation technology

4.1 all sectors of society make joint efforts to promote the market-oriented development of incineration industry. With the acceleration of urbanization, people have generally improved their living standards, and at the same time, domestic waste has increased dramatically. Landfill is a widely used treatment method for municipal solid waste. The practice proves that this method is not effective. The biggest drawback is that the utilization rate of land is gradually reduced. Therefore, it is imperative to vigorously promote waste incineration technology. From the technical point of view alone, compared with landfill, waste incineration power generation technology has more advantages, but it also faces many difficulties in the process of waste incineration power generation, which requires the joint efforts of the public, relevant enterprises and the government to ensure its smooth implementation. Therefore, the government must formulate relevant policies, strictly supervise and give play to its supervisory role

4.2 strive to develop and develop domestic large-scale waste incineration devices that are economical, practical and suitable for the characteristics of waste in China. However, the incineration method has a high investment. Currently, the incinerators that can be produced in China usually have a low degree of automation, poor operation stability and relatively weak treatment capacity, and are not suitable for large-scale centralized Incineration of municipal waste. If all foreign equipment and technologies are imported, higher operating costs will be incurred and the construction investment of local governments will be increased. Based on this, the research and development of domestic large-scale waste incineration devices that are economical and applicable and consistent with the characteristics of foreign waste is of great significance to the development of environmental protection industry and the improvement of waste pollution status

4.3 strengthen publicity and supervision. "Avoidance movement" means that residents or local units are worried that construction projects (such as waste power plants and other avoidance facilities) will bring many negative effects on health, environmental quality and asset value, so as to stimulate people's aversion complex. The government should incorporate waste incineration facilities into urban planning, ensure the public's right to know and participate, and alleviate the public's "avoidance mentality". At the same time, strengthen the supervision of waste incineration power plants. Change "avoiding neighbors" into "benefiting neighbors". Set up shared areas for the surrounding residents, match greening, sports and leisure facilities according to local conditions, implement preferential water supply, heat supply and power supply services, arrange people to work nearby, and make short-term compensation of 0.5% of the monthly export amount The fluctuation of USD 300million has been transformed into a long-term sustainable behavior, and efforts have been made to form a community of interests between waste incineration facilities and residents and communities. Change the "neighbor avoidance effect" into "neighbor benefit benefit" to realize shared development

4.4 strengthen waste classification and establish a complete set of classified waste treatment system. Improve the collection, storage and transportation system, comprehensively promote closed collection and transportation, and realize dry and wet classified collection and transportation. Strengthen the treatment and disposal of landfill leachate, incineration fly ash and odor. Appropriate subsidies shall be given to waste incineration power generation projects. The waste to energy power generation project is a municipal public welfare and environmental protection project undertaken by enterprises. The energy recovery form of the project is mainly electric energy, and its income is the income from the export of electric energy and the waste treatment subsidies given by the government. It is suggested that the government departments, environmental sanitation, electric power, price and other relevant administrative departments should give preferential treatment and appropriate support to the waste subsidies of the incineration plant from the perspective of macro benefits

4.5 it is necessary to strengthen the fine management of waste incineration power generation technology. For the purpose of fine management of waste incineration power generation technology, and a breakthrough has been made, strengthening the technical management and innovation in the whole process of waste incineration equipment R & D, engineering construction and operation management is an important condition for improving the production and management level of various waste incineration, and is the guarantee and driving force for realizing the high efficiency, safety and environmental protection of production management. Through the fine management of waste incineration technology, promote the process, standardization, digitization and informatization of waste incineration technology, and ensure zero pollution emission in all links of waste incineration power generation


with the development of economy and the continuous improvement of people's living standards, the treatment of domestic waste has aroused strong concern of governments at all levels. Domestic waste incineration power generation is a good treatment idea, which is not only in line with the current development concept of ecological treatment, but also conducive to economic development and effective utilization of resources. In recent years, we have attached great importance to environmental governance and put forward the general goal of building "Yichun model" for ecological civilization construction and the grand blueprint of building "beautiful countryside". Therefore, it is urgent to carry out the overall planning and layout of the city's domestic waste incineration power generation

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