Based on nearly three decades of experience in the treatment of municipal waste, through the incineration of domestic waste power generation, sanitary landfill and biochemical treatment and other ways of treatment of the repeated demonstration and comparison, basically determined that the sanitary landfill and incineration of power generation of the two main ways of treatment, which have their own advantages and disadvantages.
(A) sanitary landfill treatment method of benefit analysis.
1, waste disposal facilities construction costs. Guangzhou Xingfeng domestic waste sanitary landfill, for example, the site design landfill capacity of about 20.17 million cubic meters, the design treatment scale of 2,000 tons per day, the design service life of 22 years, the total investment of 680 million yuan. According to this calculation, the average construction cost per ton of sanitary landfill disposal facility is about $42.34.
2, waste disposal operating costs. After the construction of sanitary landfill, garbage into the landfill needs a lot of manpower and material resources for processing operations. Guangzhou Xingfeng domestic waste sanitary landfill, for example, the field covers an area of 451,700 square meters, daily about 120 people need to landfill, sewage treatment and various maintenance and management operations, in 2007 the total operating expenses of the field of about 72 million yuan, the annual treatment of 2.4 million tons of garbage, an average of each ton of garbage treatment operating costs of about 30 yuan.
3, the landfill after the closure of the re-greening construction and routine maintenance costs. After the landfill is filled, the need for re-greening, buried in the underground waste generated by sewage and methane gas also need to be collected and processed for another twenty years before safety. Guangzhou Xingfeng sanitary landfill designed to handle the scale of 2,000 tons per day, but from August 2002 put into use after overloading, now receive more than 8,000 tons of garbage per day, exceeding the design of the scale of treatment 3 times the service life from the design of the 22 years down to 8 years, the end of 2010 to fill up the potential to expand capacity after the continuous excavation. According to estimates, the field closure re-greening one-time construction costs of about 94 million yuan, after the closure of the first year of treatment of sewage and biogas and other maintenance costs need to be funded 7 million yuan, and may be reduced year by year thereafter, twenty years a total need for about 100 million yuan, an average of each ton of garbage closure of the field after the re-greening and maintenance costs of about 12 yuan.
4, land resources cost is huge. Landfill construction requires a large amount of land resources, filled with re-greening in addition to greening, can not be used for other functions, land regeneration in a hundred years basically no longer have. After the landfill has been filled up, the construction of a new landfill requires new land acquisition.
5, garbage resource waste is huge. Domestic garbage is known as a misplaced resources, urban garbage contains a large amount of organic matter, according to a sample survey in 2003, Guangzhou City, domestic garbage wet base low calorific value has reached 5500-6000kJ/kg. in accordance with the "municipal garbage treatment and pollution prevention technology policy", has reached the incineration method of treatment requirements. According to statistics, last year, the country filled up about 12,000,000,000 tons of garbage for nothing, except for biogas due to the great danger of collecting and recycling power generation, basically no recycling. Biogas power generation facilities need to be supported by the government to build, biogas power generation revenue is only enough to maintain the operation of the equipment and routine maintenance.
6, the potential environmental impact. Sanitary landfill as a large source of pollution, leachate and heavy metals, etc. may affect the environment, in order to prevent leachate seepage on the surface water system caused by pollution, the need to invest in maintaining the environment, to eliminate potential threats. Guangzhou Xingfeng sanitary landfill construction of domestic waste, taking into account its possible pollution of the downstream of the Jinkeng reservoir, Jinkeng reservoir for the local drinking water source, Guangzhou City, Guangzhou City, and the local agreement to lay a special 38-kilometer-long water pipeline to the local area from Guangzhou, the cost of the project amounted to 140 million yuan, and permanently provide clean tap water for local residents.
(ii) Benefit analysis of incineration power treatment method.
1, the construction cost of waste treatment facilities. Guangzhou City, as an example of waste incineration power generation plant one, the plant is designed to handle the scale of 1,000 tons per day, the design service life of 30 years, the total investment of 725 million yuan. According to this calculation, the average cost of construction of waste incineration power generation treatment facilities per ton is about $66.21.
2, waste disposal operating costs. Waste incineration power generation operating costs are high, in Guangzhou City, for example, waste incineration power generation plant, in 2007, the plant's first year of formal operation costs 48 million yuan, 350,000 tons of garbage per year, an average of 138 yuan per ton of garbage operating costs. But the plant with waste incineration power generation revenue also amounted to 50 million yuan, power generation revenue and operating costs are basically the same.
3, waste incineration power plant out of service costs. Waste incineration power plant general design life of 30 years, China's waste incineration power generation started late in the last century, the 1990s Shenzhen built China's first waste incineration power plant, and later Shanghai, Beijing, Guangzhou, Ningbo, Zhuhai, Foshan and other cities have to build waste incineration power plant. Waste incineration power plant to reach the end of its useful life to stop using, environmental pollution problems also disappeared, will not produce new pollution, so there will be no late maintenance costs. Equipment and facilities can be reused after maintenance or renewal.
4, the cost of land resources is small. Waste incineration power plant compared with the sanitary landfill, covers an area much smaller, to Guangzhou City, for example, Guangzhou City, waste incineration power plant a day to deal with 3,000 tons of garbage, covers an area of only 101,700 square meters. With an area of 451,700 square meters of Guangzhou Xingfeng domestic waste sanitary landfill, compared to only 22.5% of its area. Incineration power plant to reach the end of its useful life, the land is not damaged, can be converted to other uses, but also in situ to continue the waste incineration power generation project, no need to re-expropriation of land for demolition and relocation of the original equipment and facilities can be reused, a significant savings in construction costs.
5, waste resource waste. When the organic content of municipal waste is high, the calorific value reaches a certain level, fill up in vain will be a waste of resources. Garbage calorific value greater than 3347kJ/kg can be incinerated, but need to add auxiliary fuels to maintain stable combustion; when the calorific value is greater than 4174kJ/kg, the garbage may not add auxiliary fuels, burning at high temperatures. China's development of the "municipal waste treatment and pollution prevention technology policy" stipulates that the calorific value of the waste is greater than or equal to 5000kJ/kg, before waste incineration can be used. Most of the urban domestic waste calorific value has reached the national standard, can be used incineration.
6, the potential impact on the environment is gradually reduced. Waste incineration on the environment is mainly the impact of waste incineration will produce dioxin-like substances, such substances are strong carcinogens, generated after the natural conditions are extremely difficult to decompose, and through the soil, plants and animals and other media into the human food chain, endangering human health. In the 1990s, many of the world's leading environmental protection industry enterprises to invest a lot of effort in the development of incineration technology and equipment, incineration process research to improve the incinerator and improve the flue gas purification system, incineration process and equipment is increasingly mature, advanced, the main equipment and ancillary facilities have been basically stereotypes supporting the flue gas in the dioxin content is greatly reduced, and the impact on the environment is also greatly reduced in foreign countries. Waste incineration technology is increasingly widely used. Guangzhou City, a high starting point for the construction of waste incineration power plant, the use of Germany's advanced technology and equipment, the flue gas dioxin content is only 0.049Ng, the impact on the environment is very small, much lower than the international safety standards of 0.1Ng (Europe), lower than China's standard of 1Ng.