Method for sorting and comprehensively utilizing municipal solid waste

A method for sorting and comprehensively utilizing municipal solid waste, comprising steps of:

• 1) feeding the municipal solid waste into a feeding tank through a feeding inlet, then outputting the municipal solid waste into a breaking device through a feeding outlet of the feeding tank;
• 2) breaking refuse bags and large blocks by the breaking device;
• 3) transporting broken refuse into a two-stage roller screen for screening, wherein dusts with a particle size of less than 3 mm are screened out, and strips are hung, the strips are fibers and strip-like plastics;
• then transporting the dusts into a settling pond;
• and separating the fibers from the plastics by heavy winnowing, wherein the fibers are for producing refuse derived fuel, and the plastics are for producing wood-plastic composite;
• and
• 4) transporting mixed refuse, formed by screening out the dusts and the strips by the two-stage screen, into a vibrating screen, wherein a hole diameter of a screen net of the vibrating screen is 10 mm, oversize products are large plastics and inorganic blocks with a particle size of over 10 mm;
• screening the oversize products by a heavy winnowing machine for separating the inorganic blocks, the large plastics and paper;
• transporting the inorganic blocks into a crushing device, then screening with the two-stage roller screen after crushing the inorganic blocks into a size of less than 3 mm;
• transporting underflow products with a particle size of no more than 10 mm into a two-room multi-functional winnowing machine for winnowing, and dividing the underflow products into heavy materials, light materials and medium materials by the two-room multi-functional winnowing machine;
• outputting the heavy materials, comprising metals, masonry, ceramics and glass, from the two-room multi-functional winnowing machine and separating magnetic materials by a magnetic separation device for recycling, and burying the masonry, the ceramics and the glass;
• mixing the light materials, comprising paper and plastics, with the large plastics and the paper screened out by the heavy winnowing machine, and separating the plastics and the paper by a vertical heavy winnowing machine, wherein the plastics are for producing the wood-plastic composite after cleaning, and the paper is for producing the refuse derived fuel;
• the medium materials comprises kitchen refuse for producing fertilizer;
• wherein producing the wood-plastic composite with the plastics comprises steps of:
• I) drying wood fiber powder, crushed to 4˜80 meshes by a drying device, with a temperature of 150° C. for 3 h;
• II) mixing the plastics obtained by heavy winnowing with the plastics obtained by the vertical heavy winnowing machine, cleaning and crushing, drying and dehydrating before granulating for obtaining mixed plastic grains with a size of 40˜60 meshes;
• and
• III) firstly adding the wood fiber powder into a high-speed mixer of a heating device and stirring for 5 min, then adding the mixed plastic grains and additive agents except compatibilizer and stirring, adding the compatibilizer 5 min before outputting, and thoroughly stirring before outputting for obtaining the wood-plastic composite;
• wherein components and contents of the wood-plastic composite are:
• polyethylene 30%˜47%, polypropylene 5%˜8%, polyvinyl chloride 10%˜15%, the wood fiber powder 30%˜35%, the compatibilizer 3%˜8%, coupling agent 0.3%˜2.4%, light stabilizer 0.3%˜0.5%, antioxidant 0.3%˜0.5%, lubricant 2%˜4%, coloring agent 1%˜3%, antistatic agent 0.2%˜0.4%, and deodorizing bactericidal preservatives 0.2%˜0.3%;
• the wood fiber powder is selected from a group consisting of poplar, peach, locust and cedar wood fiber powder;
• the compatibilizer is HD900E ester compatibilizer;
• the coupling agent is titanate JTW-130 coupling agent;
• the light stabilizer is bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate;
• the antioxidant is 3-methyl-4-isopropyl-phenol;
• the lubricant is polyethylene wax;
• the coloring agent is quinacridone coloring agent;
• the antistatic agent is octadecyl dimethyl hydroxyethyl quaternary ammonium nitrate;
• and the deodorizing bactericidal preservatives is SW100 deodorant of YITERTM.