CN112940767B - Harmless high-carbon conversion method for non-meal domestic garbage, product and application thereof - Google Patents

Abstract

The invention discloses a harmless high-carbon conversion method of non-meal domestic garbage and a product thereof, wherein the method comprises the following steps: the thermoplastic polymer material with the weight ratio of more than 10 percent in the non-meal domestic garbage is utilized, or the thermoplastic polymer material is additionally added to ensure that the weight ratio of the thermoplastic polymer material in the non-meal domestic garbage is more than 10 percent, and one or more of devolatilization, dechlorination, partial carbonization, increase of the bulk ratio, formation of a special hole structure and granulation are completed in plastic processing equipment under the conditions of vacuumizing, high temperature, shearing force, compression, expansion foaming and wrapping and bonding of a thermoplastic polymer material melt in the presence or absence of an auxiliary agent, so that the high-carbon-content solid material is obtained. The invention also provides the application of the high-carbon-content solid material as a high-calorific-value fuel or a high-value chemical product obtained by gasifying, liquefying and/or chemically converting the high-carbon-content solid material into the high-value chemical product in a coal chemical industry process.

Description

A harmless high-carbon conversion method of non-meal household waste and its products and applications

technical field

The invention relates to the technical field of environmental protection, in particular to a harmless high-carbon conversion method of non-meal domestic garbage and its product and application.

Background technique

Domestic garbage is a by-product of human life, which is produced in large quantities every day. With the development of social economy and the improvement of people's living standards, the per capita production of domestic garbage is also increasing. Due to the complex composition of domestic waste, the high cost of recycling and lack of economic benefits, landfill and incineration are basically the main treatment methods. However, landfills occupy a lot of land, and there are fewer and fewer sites that can be used as landfills, and the landfilled domestic waste pollutes the environment; waste incineration is another treatment method that is widely used, but the combustion value of domestic waste It is not high, and the economic benefit as a fuel is not high, and the more serious problem is that waste incineration is prone to produce high carcinogen dioxins, which will cause excessive dioxins around waste incineration plants, which has aroused social concern. Meal waste is easy to degrade and can be effectively treated and utilized as compost, instead of meal waste, due to its complex components, it is still basically disposed of by incineration, failing to achieve high value-added recycling, and it is difficult to generate economic benefits , which makes the disposal of non-meal domestic waste fall into the predicament of no self-hemopoiesis and difficult sustainable development. Therefore, it is necessary to study the high value-added recycling of non-meal household waste and realize the economic benefits of waste recycling itself.

For the high-value recycling of non-meal waste, it is necessary to know its composition. According to statistics, non-meal household waste includes the following components: 30% of paper, 20% of rubber and plastic, 8% of fiber, 10% of bamboo and wood, 8% of glass, 8% of metal, and 8% of dust. %, moisture and other volatile components account for 8%, and the proportion of each component will vary with different garbage. At the same time, among these materials, there are also a large number of wastes composed of several materials, such as paper-plastic composite, aluminum-plastic composite, etc. Composites and other materials make the components of garbage more complex and increase the difficulty of disposal. Among them, glass, metal and dust belong to inorganic components, which are easy to separate out due to their large specific gravity, and the others are all organic components. Most of the organic components contain carbon and hydrogen elements, which have the highest economic value. These components can also be burned, which is why they can be disposed of by incineration. However, carbon-containing organic matter is only used as fuel and does not fully reflect its economic value, which belongs to the lowest-end recycling application. Organic components can achieve high value-added recycling, such as high-temperature gasification and liquefaction to produce high-value gas and fuel oil, or chemical catalytic reactions to convert them into high-value-added chemical products. To achieve these transformations, there are mature chemical processes, such as mature coal chemical processes, which can be used with these mature processes and existing equipment, but the premise is that the raw materials must meet the requirements of these processes, such as high carbon content, Control of moisture content, content control of components that are toxic to catalysts, bulk ratio of raw materials, special pore structure, particle shape, etc. However, the existing treatment of domestic waste is basically just simple treatment, such as preliminary sorting, separation of inorganic components such as metal and glass, water control and crushing. The materials after these simple treatments cannot meet the raw material requirements for high value-added transformation, so the existing processes and equipment cannot be directly used for the recycling of domestic waste.

Contents of the invention

Aiming at the above-mentioned technical problems and the deficiencies in this field, the present invention provides a harmless high-carbon conversion method of non-meal waste domestic waste, which can produce high-carbon solid materials that meet the high-value conversion process requirements of domestic waste, and realize The high value-added recycling of domestic waste reflects the economic benefits of domestic waste recycling.

In order to realize the non-toxic/harmless high-carbon conversion of non-meal garbage, the inventors conducted in-depth research on the composition characteristics of household garbage and related recycling processes. A large amount of organic components in domestic waste are basically carbon elements. These elements have a high recovery value and can be recycled. In the chemical industry, the industries that use carbon as the main raw material are mainly coal gasification and coal chemical industry. These processes are mainly based on coal, and the carbon element is mainly used. Under certain temperature and pressure, through the action of catalysts, etc., Preparation of high value-added fuel or chemical products. In these processes, there are requirements for the raw materials: (1) In order to prevent catalyst poisoning, reduce the toxic components in the raw materials as much as possible, mainly to control the chlorine content; (2) In order to improve the efficiency of the reactor, the raw materials must have certain (3) Higher carbon content; (4) In order to improve the efficiency of the catalyst, the raw material is required to have a special pore structure and porosity.

Non-meal waste, even after some treatment, such as sorting, dehydration, crushing, etc., can not meet the raw material requirements of the aforementioned existing processes, and there are the following problems: (1) The plastic components in non-meal waste, due to the accumulation The large-scale use of vinyl chloride will have a certain amount of chlorine, which will cause poisoning of the treatment catalyst; (2) the garbage is relatively fluffy and has a small bulk density; (3) in addition to carbon, the garbage also contains other elements. Insufficient; (4) does not have a special pore structure and porosity. Therefore, these non-meal wastes still need to be treated before the existing carbon conversion technology can be used to achieve high-value recycling.

In terms of treatment methods, using conventional high-temperature gasification devices and processes in this field, due to the lack of functions such as strong shearing, compression, and foaming, the processed materials still have high chlorine content, low stacking ratio, and difficult control of carbonization As well as problems such as the inability to obtain materials with a porosity that meets the requirements, it is also necessary to study new processing methods.

Aiming at these problems, the present invention provides a harmless high-carbon conversion method of non-meal waste, which includes: using the existing thermoplastic polymer material in the non-meal waste which accounts for more than 10% by weight, or through additional Adding thermoplastic polymer materials so that the proportion of thermoplastic polymer materials in the non-meal garbage is greater than 10%, with or without the presence of additives, in plastic processing equipment, using vacuum, high temperature, shear force, Compression and expansion foaming and encapsulation and bonding of the thermoplastic polymer material melt to complete one or more of devolatilization, dechlorination, partial carbonization, increasing the bulk ratio, forming a special pore structure, and granulation item to obtain high-carbon solid materials;

The auxiliary agent includes at least one of a catalyst and a blowing agent for promoting the decomposition of garbage components.

Through research, the inventor has surprisingly found that by utilizing the thermoplastic polymer material in the non-dinner domestic waste or additionally added, with or without the presence of additives, in plastic processing equipment such as twin-screw extruders Combining with a certain process, under the action of high temperature, shear force, compression and foaming, and using the melt bonding effect of thermoplastic polymer materials, the devolatilization, dechlorination, partial carbonization of non-meal waste and domestic waste can be realized. Ratio, forming a special pore structure and granulation, and obtaining a high-carbon material with a high heap ratio, a special structure, and non-toxic components. These materials can directly use the existing carbon conversion process technology and equipment to realize coal gasification or prepare chemical products to achieve high-value recovery. In plastic processing equipment such as twin-screw extruders, it not only enables chemical reactions such as dechlorination and carbonization to occur, but also changes the shape and structure of materials, and its continuous production has higher production efficiency than traditional reactors. .

The above-mentioned non-meal garbage has complex components, including metal, glass, dust, etc., and is of different sizes. Before being processed by plastic processing equipment, it is preferable to carry out pretreatment, mainly including sorting, dehydration and crushing. Sorting can separate metals through magnetic separation; through flotation and winnowing, garbage can be classified according to the difference in specific gravity, and inorganic components such as glass, ceramics and dust can be removed. Use pressing or centrifuging equipment to remove free water from garbage. Use the crushing equipment to crush the garbage to a certain size, so that the materials can be conveniently added to the plastic processing equipment.

Preferably, the non-meal household garbage is sorted, dehydrated and crushed in advance, and then mixed with thermoplastic polymer materials or directly added to plastic processing equipment;

The dehydration refers to reducing the water content in the non-meal household garbage to below 10wt%;

The crushing refers to crushing the non-meal domestic garbage to 2-4 cm.

In the harmless high-carbon conversion method of non-meal domestic waste, it is necessary to ensure that the high-temperature plasticizable thermoplastic polymer material accounts for more than 10% (by weight) in the domestic waste. Thermoplastic polymer materials, usually carbon-containing organic polymer compounds, preferably chlorine-free polyolefin materials, which do not contain harmful components, can withstand higher temperatures, and form melts at high temperatures. Each component in the garbage has the functions of wrapping, agglomeration and bonding, which can effectively change the pile ratio of the garbage. At the same time, the melt has fluidity, can be transported in plastic processing equipment, and can also be carbonized at high temperature. According to research, these plasticizable thermoplastic polymer materials should account for more than 10% of the weight of the garbage in order to achieve effective wrapping and bonding, as well as provide fluidity.

The thermoplastic polymer material mentioned above can be waste or fresh raw material, preferably waste from the perspective of cost; it can be added separately, or it can be self-contained in domestic waste. Garbage contains a relatively high proportion of polymer waste, and polymer materials include thermoplastic polymer materials and thermosetting polymer materials. Thermosetting polymer materials are cross-linked polymer materials that cannot be melted at high temperatures, so they cannot be provided. Wrapping and bonding also do not provide fluidity, so plasticizable thermoplastic polymers are required.

Further preferably, the chlorine-free polyolefin material includes at least one of polyethylene (PE) and polypropylene (PP).

In addition, in order to promote dechlorination and carbonization, some catalysts can also be added, and the added amount is preferably 0.1%-5% of the weight of the non-meal household waste. These catalysts include at least one of acidic compounds, basic compounds, and compounds that can generate acidic species during the high temperature process.

In some preferred examples, the acidic compound includes at least one of sulfuric acid, phosphoric acid, polyphosphoric acid and the like.

In other preferred examples, the basic compound includes sodium hydroxide and the like.

In some other preferred examples, the compound that can generate acidic substances during the high temperature process includes at least one of ammonium polyphosphate, diethyl hypophosphite, melamine polyphosphate, piperazine pyrophosphate and the like.

In the presence of these catalysts, the decomposition of materials can be further promoted, and the carbon content can be increased under the same process conditions.

In order to control the porosity, a foaming agent may also be added, preferably including at least one of AC foaming agent, liquid hydrocarbon, white oil, etc., and the added amount is preferably 0.1% to 8% of the weight of the non-meal domestic waste. Through the foaming effect of the foaming agent, the porosity and bulk density of the particles can be effectively controlled. The liquid hydrocarbons include naphthenes, aromatics, olefins and the like.

The plastic processing equipment includes one or more combinations of twin-screw extruder, single-screw extruder, internal mixer, open mill, etc., which can realize high temperature, strong shear force and compression, Foaming and other effects, and more efficient. The thermoplastic polymer material will first be melted and plasticized into a melt, and the non-plasticized components in the garbage will be wrapped, compressed and bonded to increase the heap ratio. The bubbles can realize a special pore structure, and can also be made into particles according to needs. Among these plastics processing equipment, preferably comprise twin-screw extruder, twin-screw extruder has included equipment such as parallel twin-screw extruder, parallel different direction twin-screw extruder and conical twin-screw extruder, preferably It is a parallel twin-screw extruder. In actual operation, two or more types of plastic processing equipment can also form multiple combinations according to the process sequence, which can complete the treatment of garbage more efficiently.

In the twin-screw extruder, to achieve dechlorination and carbonization, these are chemical actions that involve the destruction of the molecular chain of the material, which is different from the physical action that does not involve the destruction of the molecular chain, such as the molten material under the normal action of the extruder. The destruction of molecular chains can be achieved by applying strong shear force and heat to waste materials. The effect of heat is determined by the temperature, and the shear force of the twin-screw extruder is determined by the screw module combination and the screw gap. For dechlorination and carbonization of waste materials, under certain conditions, temperature and screw shear force have the same effect, that is, higher temperature is beneficial to dechlorination and carbonization, and at a certain temperature, stronger shear force is also Conducive to dechlorination and carbonization. However, if the temperature is too high, it will increase the cost of energy consumption. At the same time, the higher temperature will make the carbonization more serious and the degree of carbonization is difficult to control. The thermoplastic component will lose its fluidity, which will easily lead to the locking of the screw, which makes the material unable to be extruded in the twin-screw. The processing is completed during exiting the machine. Therefore, it is necessary to reduce the temperature requirement through shear force, taking into account the dechlorination and carbonization and the operability of the process.

For the treatment of garbage materials, in order to reduce the temperature, it is necessary to provide a strong shear force. On the one hand, it is necessary to configure a combination of strong shear force modules. On the other hand, a smaller screw gap is required. The smaller the screw gap, the higher the shear force. Big. The conventional screw gap is 0.3mm, but for the treatment of waste materials, in order to achieve dechlorination and carbonization, stronger shear force is required. After research, it is found that the screw gap is not greater than 0.2mm to achieve better results. In addition, according to the characteristics of waste material treatment, the waste material is gradually carbonized from entering the twin-screw extruder to leaving the twin-screw extruder, so the fluidity of the material is getting lower and lower, and the smaller screw gap is not conducive to the material If the conveying is serious, the screw will be stuck. Therefore, at the end of the extruder, the screw gap should be larger. The research found that it is not less than 0.4mm. Therefore, for the treatment of waste materials, it is necessary to choose an extruder with a variable screw gap. Extrusion configuration, and taking into account dechlorination, carbonization and material transportation in the production process, the configuration of the screw combination is: the front section of the strong shear small gap part is not less than 60% of the entire screw length, and the rear end weak shear large gap part is not lower 20% of the entire screw length. This variable-gap screw combination design is different from conventional twin-screw extruders. Conventional twin-screw extruders basically complete the function of plasticizing and melting. Generally, the shear force is controlled by module combination, while the screw gaps are basically consistent. Screw combination with variable clearance. The strength of the shear force can be indirectly measured by the linear speed of the screw. For the treatment of waste materials, the linear speed is required to be greater than 0.4m/s. Garbage materials need a certain residence time to complete dechlorination, carbonization, compression, expansion and foaming in the twin-screw extruder. Studies have found that the residence time of garbage materials in the extruder is greater than 30s. The residence time of the material is determined by the screw length and the screw speed. Therefore, for the treatment of waste materials, the length-to-diameter ratio of the twin-screw extruder is 40-80:1, and the screw speed is 100-1200rpm during operation, so that the material can bear the shear. The tangent speed is greater than 0.4m/s, and the material residence time is greater than 30s. In addition, because the waste material contains chlorine, the dechlorination reaction will generate acid gas, and the material of the screw should be corrosion-resistant; and the waste material may contain hard materials such as metal and glass, and the material of the screw should also be wear-resistant and hard. quality metal material.

Garbage materials need to be dechlorinated under the action of temperature. At a lower temperature, the volatile matter is first removed, and at a higher temperature, the dechlorination is completed. For example, polyvinyl chloride (PVC) material is greater than 200 ° C. Dechlorination will occur, and with the vacuum system, the chlorine in the garbage can be removed to avoid poisoning the catalyst in the subsequent high-value treatment process. At the highest temperature, the organic components remove other elements to achieve Carbonization, other elements are removed in the form of gas, which can increase the carbon content in the material. The temperature here is usually much higher than the plasticizing temperature of the polymer material due to the destruction of the molecular chain of the material, which is different from ordinary temperature settings for plastic processing.

In plastic processing equipment, combined with material composition, temperature conditions and controlled vacuum, the bonding and foaming effects of thermoplastic polymer material melts can be used to prepare materials with special pore structure and porosity, increase the surface area, and meet the requirements of carbon element catalysis. Transformation needs, improve the catalytic efficiency of the catalyst.

Preferably, said vacuuming refers to controlling the degree of vacuum below -0.05MPa.

In a preferred example, the plastic processing equipment includes a twin-screw extruder, and the high temperature means that the material temperature is 200-500°C, more preferably 400-500°C. When the twin-screw extruder is not specially designed and adaptively optimized, a higher temperature can ensure better dechlorination and carbonization.

In order to reduce the processing temperature, in another preferred example, the plastic processing equipment includes a twin-screw extruder with a variable screw pitch feature, the small gap part of the strong shear in the front section is not less than 60% of the entire screw length, The spacing is not greater than 0.2mm, the weak shear large gap at the rear end is not less than 20% of the entire screw length, and the screw spacing is not less than 0.4mm; the high temperature refers to the temperature of the material at 150-400°C. When the above-mentioned special design and adaptability optimization are carried out on the twin-screw extruder, the material can undergo chemical reactions such as dechlorination and carbonization at a relatively low temperature. On this basis, it is further preferred that the plastic processing equipment further includes an internal mixer, and the non-meal domestic waste is first mixed in the internal mixer at 150-500°C for 0.5-1.5 hours before being added to the in a twin-screw extruder.

The invention also provides the high-carbon solid material prepared by the harmless high-carbon conversion method of non-meal waste domestic waste.

Preferably, the high-carbon-containing solid material has a carbon content of more than 65wt%, a chlorine content of less than 700ppm, a bulk density of more than 0.55g/cm ³ , a volatile content of not more than 0.06wt%, and a porosity of not less than 10%.

The obtained high-carbon solid materials can be made into granules through plastic processing equipment, or powder materials with different particle sizes can be prepared through pulverizers, and can also be directly connected with subsequent coal gasification devices or carbon conversion processes, using high-temperature materials Carry out subsequent high-value-added conversions.

Through the harmless high-carbon conversion method of non-meal domestic garbage, high-carbon-containing solid materials without poisoned catalyst components, high heap ratio, and special pore structure can be obtained.

As a general inventive concept, the present invention also provides the use of the high-carbon-containing solid material as a high-calorific-value fuel or used in a coal chemical process to produce high value-added chemicals through gasification, liquefaction and/or chemical conversion.

The harmless high-carbon conversion method of non-meal domestic waste of the present invention can also be tried to be used for the treatment of other non-domestic solid organic wastes, such as the treatment of some industrial solid wastes, through the adjustment of technical parameters.

Compared with the prior art, the main advantages of the present invention include: the present invention utilizes the thermoplastic polymer material contained in non-meal waste domestic waste or externally added, preferably chlorine-free polyolefin material, and passes through high temperature in plastic processing equipment , shearing force, compression, expansion and foaming, and the bonding of polymer material melts, the devolatilization, dechlorination, partial carbonization of non-meal waste, increasing the heap ratio, and forming a special pore structure and granulation to obtain high-carbon materials with high heap ratio, special structure, and non-toxic components. The method can utilize mature plastic processing equipment or the adaptively improved plastic processing equipment described in the present invention, has simple process, convenient operation and high processing efficiency, and can realize high-value recycling of non-meal waste. The obtained solid material with high carbon content can be easily gasified, liquefied and converted into chemical products by using the existing coal chemical process, so as to realize the high-value recycling of domestic waste, which not only protects the environment, but also realizes economic value.

detailed description

Below in conjunction with specific embodiment, further illustrate the present invention. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. The operating methods not indicated in the following examples are generally in accordance with conventional conditions, or in accordance with the conditions suggested by the manufacturer.

Example 1

After sorting and dehydrating the non-dinner domestic waste (garbage component 1) from the garbage collection station, the moisture content is 8.2wt%, and it is crushed by a pulverizer into blocks or flakes with a size of 2 to 4 cm. According to the sub-analysis, the content of polyethylene and polypropylene mixture (thermoplastic component, chlorine-free polyolefin) is 12.2wt%, which can be used directly. Using a specially configured co-rotating twin-screw extruder, the basic configuration of the extruder is: screw diameter D = 65mm, length-to-diameter ratio L/D = 52, motor power P = 120KW, screw combination front screw interval 0.2mm, Accounting for 70% of the length of the screw, the screw gap at the back section of the screw is 0.4mm, accounting for 30% of the length of the screw. The processing conditions of the extruder are as follows: the highest temperature is 350°C, the screw speed is 600rpm, the vacuum is -0.06MPa, no filter is added, and the die head pressure is 15MPa. Non-meal waste can be dechlorinated, carbonized, melt-compressed, devolatilized, and contain holes after being processed by an extruder. The following properties are characterized and tested, and the results are shown in Table 1.

(1) Carbon content test

Reference standard: GB/T 3780.25-2018 "Determination of Carbon Content", measuring the carbon content in garbage.

(2) Determination of chlorine content

Reference standard: GB/T 6324.9-2016 "Test Methods for Organic Chemical Products Part 9: Determination of Chlorine", measuring the chlorine content in garbage.

(3) Determination of bulk density

Reference standard: ASTM D7481-2009 "Standard Test Method for Determination of Loose and Bulk Powder Density Using a Graduated Cylinder", which measures the bulk density of garbage.

(4) Determination of porosity

The porosity of the treated garbage samples was tested by mercury intrusion porosimetry using a mercury porosimeter.

(5) Volatile content test

The volatile matter content in the garbage was tested by the high-temperature thermogravimetric method. Test conditions: keep at 120°C for 30 minutes to constant weight, the percentage of the weight lost to the weight of the initial material is the percentage of volatile content.

Example 2

Same as Example 1, the difference is that the thermoplastic component is 6.2wt% in the non-dinner domestic garbage (garbage component 2) from the garbage collection station, and 5wt% of recycled industrial polymer is added before the twin-screw extruder is processed. vinyl film. The properties of the treated materials are shown in Table 1.

Example 3

Same as Example 1, except that the maximum temperature of the twin-screw extruder was set to 320°C. The properties of the treated materials are shown in Table 1.

Example 4

Same as Example 1, except that the vacuum of the twin-screw extruder is set to -0.9MPa. The properties of the treated materials are shown in Table 1.

Example 5

Same as Example 1, except that a twin-roller internal mixer with a volume of 110 L was first used, the temperature was set at 250° C., and the internal mixing time was 60 minutes, and then the material was transferred to a twin-screw extruder for processing. The properties of the treated materials are shown in Table 1.

Example 6

Same as Example 1, except that an additional 0.5 wt% sodium hydroxide solid was added to the material. The properties of the treated materials are shown in Table 1.

Example 7

Same as Example 1, except that an additional 1wt% of 64# white oil was added to the material. The properties of the treated materials are shown in Table 1.

Example 8

Same as Example 1, except that the full screw pitch of the twin-screw extruder is 0.3mm, and the temperature is set at 400°C. The properties of the treated materials are shown in Table 1.

Comparative example 1

Same as in Example 1, a twin-roller internal mixer with a volume of 110 L was used instead of a twin-screw extruder, the temperature was set at 350° C., and the internal mixing time was 60 minutes. The properties of the treated materials are shown in Table 1.

Table 1

Comparative example 2

Same as Example 1, except that only sorting, dehydration and pulverization were carried out, and no high-temperature treatment was carried out with a twin-screw extruder. The results are shown in Table 2.

Comparative example 3

Same as Example 1, except that the set temperature is 130°C, the results are shown in Table 2.

Comparative example 4

The same as Example 2, the difference is that no 5wt% recycled industrial polyethylene film is added, and the results are shown in Table 2.

Comparative example 5

The same as Example 1, the difference is that the garbage is put into the conventional high-temperature gasification furnace, and the temperature is set at 350°C. The results are shown in Table 2.

Comparative example 6

Same as Example 1, the difference is that the entire screw gap of the twin-screw extruder is 0.2mm, and the screw is locked and cannot work normally.

Comparative example 7

Same as Example 1, except that the entire screw gap of the twin-screw extruder is 0.4mm, and the results are shown in Table 2.

Comparative example 8

Same as Example 1, except that the screw speed of the twin-screw extruder is 80 rpm, the results are shown in Table 2.

Comparative example 9

It is the same as Example 8, except that the highest temperature is set at 320° C., and the results are shown in Table 2.

Table 2

In addition, it should be understood that after reading the above description of the present invention, those skilled in the art may make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of the present application.

Claims (10)

1. A harmless high-carbon conversion method of non-meal household garbage is characterized by comprising the following steps: utilizing the thermoplastic polymer material with the weight ratio of more than 10 percent in the non-meal domestic garbage, or additionally adding the thermoplastic polymer material to ensure that the weight ratio of the thermoplastic polymer material in the non-meal domestic garbage is more than 10 percent, and utilizing the functions of vacuumizing, high temperature, shearing force, compression, expansion and foaming and the wrapping and bonding of the thermoplastic polymer material melt in plastic processing equipment in the presence or absence of an auxiliary agent to complete one or more of devolatilization, dechlorination, partial carbonization, increase of stacking ratio, formation of a special hole structure and granulation so as to obtain a high-carbon-content solid material;

the thermoplastic polymer material comprises a chlorine-free polyolefin material;

the auxiliary agent comprises at least one of a catalyst and a foaming agent for promoting the decomposition of the garbage components;

the plastic processing equipment is a double-screw extruder, or the combination of one or more of a single-screw extruder, an internal mixer and an open mill and the double-screw extruder; the maximum temperature of the double-screw extruder is 350 ℃;

the double-screw extruder is characterized by variable screw pitch, the front-section strong-shearing small gap part of the double-screw extruder is not less than 60% of the length of the whole screw, the screw pitch is not more than 0.2mm, the rear-end weak-shearing large gap part of the double-screw extruder is not less than 20% of the length of the whole screw, and the screw pitch is not less than 0.4mm;

the carbon content of the high carbon-containing solid material is more than 65wt%, the chlorine content is less than 700ppm, and the bulk density is more than 0.55g/cm ³ The volatile matter is not more than 0.06wt%, and the porosity is not less than 10%.

2. The non-food household garbage harmless high carbon conversion method according to claim 1, characterized in that the non-chlorine containing polyolefin material comprises at least one of polyethylene, polypropylene;

the catalyst comprises at least one of an acidic compound, a basic compound, and a compound that can generate an acidic substance during the high temperature process;

the acidic compound comprises at least one of sulfuric acid, phosphoric acid and polyphosphoric acid;

the alkaline compound comprises sodium hydroxide;

the compound capable of generating acidic substances in the high-temperature process comprises at least one of ammonium polyphosphate, diethyl hypophosphite, melamine polyphosphate and piperazine pyrophosphate;

the addition amount of the catalyst is 0.1-5% of the weight of the non-meal household garbage;

the foaming agent comprises at least one of an AC foaming agent, liquid hydrocarbon and white oil;

the addition amount of the foaming agent is 0.1-8% of the weight of the non-meal domestic garbage.

3. The harmless high-carbon conversion method of non-food domestic garbage according to claim 1, characterized in that the vacuum degree is controlled below-0.05 MPa.

4. The harmless high-carbon conversion method of non-food domestic garbage according to claim 3, characterized in that the high temperature means that the material temperature is 200-500 ℃.

5. The harmless high-carbon conversion method of non-food domestic garbage according to claim 3, characterized in that the high temperature means that the material temperature is 150-400 ℃.

6. The method for harmless high-carbon conversion of non-meal household garbage according to claim 5, wherein the plastic processing equipment is a combination of an internal mixer and a twin-screw extruder, and the non-meal household garbage is internally mixed by the internal mixer at 150-500 ℃ for 0.5-1.5 h and then added into the twin-screw extruder.

7. The harmless high-carbon conversion method of non-food waste household garbage according to any one of claims 4 to 6, characterized in that the length-diameter ratio of the screw of the twin-screw extruder is 40 to 80, the rotating speed of the screw during operation is 100 to 1200rpm, the shearing linear speed borne by the material is more than 0.4m/s, and the retention time of the material is more than 30s.

8. The harmless high-carbon conversion method of non-food household garbage according to claim 1, characterized in that the non-food household garbage is subjected to sorting, dewatering and crushing operations in advance, and then is mixed with thermoplastic polymer materials or is directly added into plastic processing equipment;

the dehydration means that the water content in the non-meal domestic garbage is reduced to be less than 10 wt%;

the crushing means that the non-meal household garbage is crushed to 2-4 cm.

9. The high carbon content solid material prepared by the harmless high carbon conversion method of the non-food waste household garbage according to any one of the claims 1 to 8.

10. The use of the high-carbon-content solid material prepared by the harmless high-carbon conversion method of the non-food domestic garbage according to any one of claims 1 to 8 as a high-calorific-value fuel or for the gasification, liquefaction and/or chemical conversion of coal chemical industry processes into high-value-added chemicals.