System and method for pyrolysis of household refuses

Abstract

The invention relates to a system and a method for pyrolysis of household refuses. The system comprises a combined type high-temperature pyrolysis rotating bed, an oil-gas separating device, a fluidized bed and a combustible gas storage tank, wherein the combined type high-temperature pyrolysis rotating bed comprises a material feeding opening, a material discharging opening and a high-temperature oil-gas outlet, a preheating area, a reaction area I and a reaction area II are arranged in a furnace body in sequence according to the rotating direction of the rotating bed, and a plasma torch is arranged on a furnace wall of the reaction area II. The system disclosed by the invention has the advantages of low operation cost, high resource utilization and energy regeneration level, good economic benefits of products, less secondary pollution, no production of dioxin and easiness for realizing industrialization and scale management of refuse pyrolysis.

Description

technical field [0001] The invention relates to the treatment of solid waste as a resource, in particular to a system and method for pyrolyzing domestic waste. Background technique [0002] Due to the mixed collection of urban domestic waste in my country, the composition of waste is complex, including: kitchen waste, plastic, rubber, paper, wood and bamboo, fabric, glass, metal, etc., and the characteristics of each component are different in particle size, hardness, moisture content, etc. , such as high moisture content of kitchen waste, light plastics are difficult to break, etc. In pyrolysis treatment, it is often necessary to use complex pretreatment to prepare primary domestic waste into raw materials that meet the requirements before it can be put into the furnace. Pretreatment generally includes sorting (magnetic separation, winnowing, manual sorting), crushing, drying, molding, etc. The pretreatment process is long and the process is complicated. The existing problem...

AI Technical Summary

Problems solved by technology

Pretreatment generally includes sorting (magnetic separation, winnowing, manual sorting), crushing, drying, molding, etc. The pretreatment process is long and the process is complicated. The existing problems mainly include: (1) the existing pretreatment technology It is difficult to ensure the efficiency of sorting and crushing, so not only a lot of manpower and material resources are wasted, but also the pretreated garbage cannot fully meet the requirements; (2) Existing pyrolysis furnaces, such as rotary kilns, fluidized beds, etc., all require The moisture content in the furnace is low, and the pyrolysis reaction must dry the garbage. Regardless of whether an indirect heat source or a direct heat source is used, a large amount of flue gas will be generated during drying. This kind of flue gas has a high concentration of odor and must be further deodorized to meet the emission standards. ; (3) The processing capacity of a single pretreatment device is generally low, and multiple devices need to be equipped. At the same time, the failure rate of the equipment is high, and it is difficult to maintain continuous and stable operation

[0003] If the garbage is directly put into the furnace for pyrolysis without pretreatment, the following problems exist in the prior art: the high moisture content (49%-60%) of the garbage leads to extremely low thermal efficiency of the system, water vapor is mixed in the pyrolysis gas, and the calorific value is low , subsequent use is difficult; the pyrolysis process is incomplete, the pyrolysis time is too long, and the product quality is poor

[0008] However, the pretreatment system inevitably uses drying. Although indirect drying is used to avoid a large amount of odor treatment, there will still be odors containing water vapor. At the same time, the energy consumption of the indirect drying system is higher than that of direct drying. The dryness is high and the energy utilization rate is low; the pyrolysis gas is fed into the combustion chamber for combustion, and the flue gas generated is used as the heat source for drying, which leads to no other products to be sold in the whole process, and the economy is poor

[0009] All in all, due to the high moisture content of domestic waste in our country, if it is dried in the pretreatment, a large amount of hot flue gas or water vapor is required. Whether it is direct drying or indirect drying, the water vapor produced is not only large in amount but also smells bad. Smell, the odor needs to be removed before it can be discharged, the whole process consumes a lot of energy and costs high

In addition, due to the mixed collection of garbage, the components of the garbage are complicated. In order to achieve a high garbage utilization rate, most processes have set up a very complicated pretreatment process. Not only is the process long, the energy consumption is large, and the sorting efficiency is difficult to guarantee.

In addition, the waste pyrolysis process is currently difficult to realize industrialization due to complex procedures and poor economic benefits.

At present, the pyrolysis temperature of the waste pyrolysis process is low, and the incomplete pyrolysis caused by the low temperature will make the post-treatment process of the pyrolysis product complicated and the cost will increase

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