阅读说明：本技术 一种利用市政污泥去除焦油的方法 (Method for removing tar by using municipal sludge ) 是由 袁浩然 王舒笑 单锐 顾菁 张军 于 2020-04-29 设计创作，主要内容包括：本发明公开了一种利用市政污泥去除焦油的方法,利用市政污泥热解碳作为催化剂载体,污泥热解碳结合金属活性物质制备形成新型复合催化剂,催化剂应用于可燃固体废弃物热解过程中焦油的去除,焦油的去除率可以达到64％；本发明的原料市政污泥来源广泛,价格低廉,且充分利用了市政污泥热解碳作为载体的优良特性,即为市政污泥提供了一种资源化的利用方法,又发明了一种新的去除焦油的材料。(The invention discloses a method for removing tar by utilizing municipal sludge, which is characterized in that municipal sludge pyrolytic carbon is used as a catalyst carrier, the sludge pyrolytic carbon is combined with metal active substances to prepare a novel composite catalyst, the catalyst is applied to removing the tar in the pyrolysis process of combustible solid wastes, and the removal rate of the tar can reach 64%; the raw material municipal sludge has wide sources and low price, and fully utilizes the excellent characteristic of the municipal sludge pyrolytic carbon as a carrier, thereby providing a resource utilization method for the municipal sludge and inventing a novel material for removing tar.)

1. A method for removing tar by using municipal sludge is characterized by comprising the following steps:

(1) performing filter pressing dehydration treatment on municipal sludge to enable the water content to be lower than 85%, then drying, and pyrolyzing the dried sludge at the temperature of 600 ℃ and 900 ℃ for 1-3 h under an inert atmosphere to obtain sludge pyrolytic carbon;

(2) loading a metal active substance on the sludge pyrolytic carbon obtained in the step (1) by a wet impregnation method, wherein the metal is selected from any one of Fe, Ni and Cu, and performing secondary calcination on the loaded solid mixture at the temperature of 600-900 ℃ for 1-3 h under inert gas to obtain the tar-removing composite catalyst taking the sludge carbon base as a carrier, wherein the loading amount of the metal active substance is 3-20%;

(3) and (3) adding the composite catalyst obtained in the step (2) into the pyrolysis process of the solid waste.

2. The method for removing tar from municipal sludge according to claim 1, wherein the inert gas in step (1) comprises nitrogen, argon, helium.

3. The method for removing tar by using municipal sludge according to claim 1, wherein the step (2) comprises the following steps: taking NiCl₂·6H₂O or FeCl₃·6H₂O or CuCl₂·2H₂Dissolving O in water to obtain a solution, weighing the sludge pyrolytic carbon obtained in the step (1), dissolving the sludge pyrolytic carbon in the solution, stirring, drying the stirred mixed solution to obtain a solid mixture, and performing secondary calcination on the solid mixture at the temperature of 600-900 ℃ for 1-3 h under inert gas to obtain a composite catalyst; wherein the mass ratio of the metal Fe or Ni or Cu to the sludge pyrolytic carbon is 0.03: 1-0.2: 1.

4. The method for removing tar with municipal sludge according to claim 1, wherein the raw material of the pyrolysis process in step (3) is combustible solid waste, including domestic garbage, agricultural and forestry waste, municipal sludge, plastics, wood, industrial solid waste; the mass ratio of the catalyst added in the pyrolysis to the solid waste is 0.1: 1-1: 1.

The technical field is as follows:

the invention relates to the technical field of solid waste treatment, in particular to a method for removing tar by using municipal sludge.

Background art:

municipal sludge is solid waste and can be used as a resource, however, most of sludge in land landfill, open air stacking and outward transportation belongs to random disposal, and the proportion of truly realizing safe disposal does not exceed 20%. Under the background of the era that natural resources are gradually deficient, the further realization of the resource utilization, energy regeneration and high-value utilization of municipal sludge is a new requirement for the municipal sludge treatment and disposal industry. The thermal conversion is an effective utilization mode of municipal sludge, the thermal conversion can convert the sludge into porous solid carbon, and the solid carbon has wide application prospects in the aspects of serving as a catalyst, an adsorbent, a soil slow-release fertilizer and the like.

Tar is generated in the thermal conversion process, is a high-aromatic hydrocarbon complex mixture with high viscosity and toxicity, can easily cause pipeline blockage and corrosion, can cause human body harm when being discharged into the environment, and is a key problem in thermal conversion research.

The invention content is as follows:

the invention aims to provide a method for removing tar by utilizing municipal sludge, which utilizes municipal sludge pyrolytic carbon as a catalyst carrier for removing tar, and the sludge pyrolytic carbon is combined with metal active substances to prepare a novel composite catalyst which is applied to removing the tar in the pyrolysis process.

The invention is realized by the following technical scheme:

a method for removing tar from municipal sludge, comprising the steps of:

(1) performing filter pressing dehydration treatment on municipal sludge to enable the water content to be lower than 85%, then drying, and pyrolyzing the dried sludge at the temperature of 600 ℃ and 900 ℃ for 1-3 h under an inert atmosphere to obtain sludge pyrolytic carbon;

(2) loading a metal active substance on the sludge pyrolytic carbon obtained in the step (1) by a wet impregnation method, wherein the metal is selected from any one of Fe, Ni and Cu, and performing secondary calcination on the loaded solid mixture at the temperature of 600-900 ℃ for 1-3 h under inert gas to obtain the tar-removing composite catalyst taking the sludge carbon base as a carrier, wherein the loading amount of the metal active substance is 3-20%;

(3) and (3) adding the composite catalyst obtained in the step (2) into the pyrolysis process of the solid waste to achieve the effect of removing tar.

The main components of sludge pyrolytic carbon obtained by pyrolyzing municipal sludge are C and high-temperature-resistant oxide SiO₂、Al₂O₃Etc., C and SiO₂The structure provides extremely favorable conditions for the catalyst to be used as a catalyst carrier; the prepared composite catalyst contains FeC and FeSiO₃Structures FeC and FeSiO₃The existence of the structure not only ensures the catalytic activity of the catalyst, but also enhances the stability of the catalyst. Meanwhile, the addition of the metal active substance enhances the tar removal capability of the tar remover.

Preferably, the inert gas in step (1) includes, but is not limited to, nitrogen, argon, helium, and the like.

Preferably, the step (2) comprises the following specific steps: taking NiCl₂·6H₂O or FeCl₃·6H₂O or CuCl₂·2H₂Dissolving O in water to obtain a solution, weighing the sludge pyrolytic carbon obtained in the step (1), dissolving the sludge pyrolytic carbon in the solution, stirring, drying the stirred mixed solution to obtain a solid mixture, and performing secondary calcination on the solid mixture at the temperature of 600-900 ℃ for 1-3 h under inert gas to obtain a composite catalyst; wherein the mass ratio of the metal Fe or Ni or Cu to the sludge pyrolytic carbon is 0.03: 1-0.2: 1.

Preferably, the raw material of the pyrolysis process in step (3) is combustible solid waste, including but not limited to domestic garbage, agricultural and forestry waste, municipal sludge, plastics, wood, industrial solid waste, etc.; the mass ratio of the catalyst added in the pyrolysis to the solid waste is 0.1: 1-1: 1.

The invention has the following beneficial effects:

1) the raw material municipal sludge has wide sources and low price, and fully utilizes the excellent characteristic of the municipal sludge pyrolytic carbon as a carrier, thereby providing a resource utilization method for the municipal sludge and inventing a novel material for removing tar.

2) The novel composite catalyst is prepared by the sludge pyrolytic carbon bonded metal active substance, is applied to removing tar in the pyrolytic process of combustible solid waste, and the removal rate of the tar can reach 64 percent.

Description of the drawings:

FIG. 1 is an SEM photograph of a composite catalyst prepared in example 1;

fig. 2 is an XRD pattern of the composite catalyst prepared in example 1.

The specific implementation mode is as follows:

the following is a further description of the invention and is not intended to be limiting.