RU2209693C1 - Method for processing domestic waste - Google Patents

Abstract

FIELD: industrial processes for complex processing of domestic waste materials and separating components suitable for secondary use and for making high-quality fertilizer. SUBSTANCE: method comprises steps of separating in screen according to fraction size in flows of hot air at simultaneously drying and loosening waste materials; then processing over-size fraction by manual sorting; processing under-size fraction by initially extracting ferrous metals, by manual sorting for separating paper, plastics, glass cans, textile, large pieces of broken glass, preserve cans, rags, large pieces of non-ferrous metal scrap; separating in centrifugal screen stones, sand, gravels; disintegrating until fraction no more than 20 mm; extracting non-ferrous metals; disintegrating until fraction 0.07 - 0.1 mm; removing particles of glass, plastics, paper, textile and feeding them for pyrolysis; composting remained organic components for receiving ecologically safe purified fertilizer and biogas. EFFECT: complex processing of domestic waste materials with possibility of secondary using its components, namely ecologically safe production of high-quality fertilizer. 8 cl, 1 dwg

Description

 The invention relates to industrial methods for the integrated processing of household waste with the allocation of components suitable for recycling and obtaining high-quality fertilizer in environmentally friendly production.

A known method of processing household waste, including sorting it to obtain useful materials, namely: waste paper, glass, plastic, wood, manufactory, metal in the amount of 4-25% of the sorted solid household waste (MSW) and tails, followed by compaction by pressing sorting tailings together with a part of the initial MSW with the tailings in the waste mixture from 25 to 75% (see patent RU 2164446, IPC ⁷ V 03 V 9/06, 65 F 5/00, 09 V 5/00).

 The disadvantage of this method is the availability of manual sorting, which is a harmful production. In addition, the known method is mainly aimed at reducing the volume of landfill with obtaining a minimum amount (4-25%) of useful components for recycling.

A known method of processing household waste (BO), in which initially preliminary manual sorting of the waste is carried out by selecting recycled (waste paper, textiles, ferrous and non-ferrous metals, glass, plastic) harmful and mineral components. The remaining waste is self-grinding, the combusted part is separated, and the non-combustible part is sieved into coarse and fine fractions. Then both fractions are sorted by selection of harmful, reusable and mineral materials and the separation of ferrous and non-ferrous metals. After sorting and separation, the coarse fraction is sent to incineration, and the coarse fraction is composted, while the compost is aerated to select film residues and sieved to select biologically inactive particles (see patent RU 2161542, IPC ⁷ V 09 V 3/00, V 03 V 9 / 06, F 23 G 5/00).

 The disadvantage of this method is the presence of harmful to human health production site preliminary manual sorting of BO. In addition, the method provides for the burning of a large fraction, which leads to environmental damage.

The closest in technical essence to the claimed is a method of processing BO, including separation by fractional composition into oversize and under-sieve fractions on a screen with a mesh size (200x250) ± 50 mm, scrap metal extraction from both fractions using constant or traveling magnetic fields, subsequent processing of under-sieve fractions in a rotating bio-drum into compost, extraction of ballast larger than 40-50 mm (glass, stones, corks) from compost on a drum screen and sending it for burning, removing black and color from it scrap metal, films. Grinding the remaining compost to a particle size of not more than 20 mm, storing it in stacks and keeping it for 2-3 months for ripening. Isolation from the oversize fraction (NF) of first large-sized constituents of sizes over 300 mm; extraction of metal, wood, plastic, paper from them. Separation of the remaining NF by morphological composition into ballast, food waste, textiles, paper and film. Food waste is sent to a bio-drum for composting, and ballast for pyrolysis or incineration. Textiles, paper and film are combined from both fractions, crushed to a particle size of no more than 60 mm, dried, re-crushed to 20 mm and briquetted for burning (see acSU 1585019, MKI ⁵ V 07 V 9/00).

 The disadvantages of this method are environmentally dirty production, due to the supply of BO from the hopper to the drum screen, where the BO are loosened and sorted by size, emitting harmful gases with an unpleasant odor into the environment, which complicates the work of the staff. In addition, partial grinding of household waste in a drum screen at the first stage and grinding of the under-sieve fraction in hammer crushers before composting leads to clogging of compost with glass and plastic, the removal of which from the compost is a time-consuming operation. The known method is mainly aimed at obtaining fuel briquettes, i.e. for the burning of BO, as well as for composting, but in a very laborious way, consisting in the initial two-day aging in the bio-drum of the under-sieve fraction and food waste of the over-sizing fraction and keeping the compost in the warehouse for 2-3 months before its final ripening, which requires large expenses for the maintenance of large heated storage areas.

 The technical result of the claimed technical solution is to provide integrated processing of BO with the possibility of reuse of most components, obtaining high-quality fertilizer in environmentally friendly production.

 The technical result is achieved by the fact that in the method of processing BO, including separation on the screen of the source material according to the fractional composition into oversize and sublattice fractions, extraction of ferrous and non-ferrous scrap metal from the separated fractions and subsequent processing of the separated fractions, separation on the screen according to the fractional composition is carried out in hot streams air with simultaneous drying and loosening of waste, the subsequent processing of the oversize fraction is carried out by manual sorting, and processing will undergo fractions are carried out by initial extraction of ferrous metals, manual sorting to separate paper, plastic, glass containers, textiles, large cullet, cans, rags, large non-ferrous scrap metal, separation of stones, sand, gravel, crushing to a fraction of not more than 20 mm on a centrifugal screen extraction of non-ferrous metal, grinding to a fraction of 0.07-0.1 mm, removing particles of glass, plastic, manufactory, paper and feeding them to pyrolysis, composting the remaining organic component to obtain an environmentally friendly th fertilizer and biogas.

In addition, the separation by fractional composition into oversize and sublattice fractions is carried out on a screen with a mesh size of 0.6 mx 0.6 m in air flows heated to a temperature of 120-150 ^o C.

 In addition, the extraction of ferrous metals from the under-sieve fraction is carried out in three stages by an electromagnetic separator made in the form of a discharge tape with an electromagnet.

 In addition, the crushing of the sublattice fraction to a particle size of not more than 20 mm is carried out on crushers of the trench-breakdown type.

 In addition, the extraction of non-ferrous metals from the crushed sublattice fraction with a particle size of not more than 20 mm is carried out in three stages on an electrodynamic separator.

 In addition, the grinding of the under-sieve fraction to a particle size of 0.07-0.1 mm is carried out in a mill.

 In addition, the removal of particles of glass, plastic, manufacture, paper and other inorganics from the fraction with a particle size of 0.07-0.1 mm is carried out in a dielectric separator.

 Comparison of the proposed technical solution with the prototype made it possible to establish the presence of distinctive features, therefore, the claimed technical solution meets the criterion of "NOVELTY".

 An analysis of technical solutions showed that the claimed combination of features that ensures the maximum utilization of BW with the highest amount of recyclable components and high-quality fertilizer in environmentally friendly production is not known from the prior art and, therefore, the claimed technical solution meets the criterion of "INVENTIVE LEVEL".

In the method of processing BO, including disinfection at the first stage, eliminating the unpleasant odor of BO by supplying hot air (120-150 ^o С) to the receiving hopper through the windows in the walls of the receiving hopper, loosening and drying the BO, conditions are provided for an environmentally friendly production of BO processing namely, after removal of ferrous scrap metal, the conditions are harmless enough for manual selection from the under-sieve fraction of large BO paper, glass containers, large cullet, plastic products, cans, rags, large non-ferrous scrap metal, which allows, during the subsequent grinding operation, to prevent clogging of the compost component with cullet, a plastic battle, i.e. get high-quality compost and at the same time materials suitable for recycling.

 In addition, the volume of recoverable materials for recycling increases due to the extraction of the same components at different stages of the method.

 In addition, a well-executed sequence of operations in which BO grinding operations were introduced only for the selection of fractions clogging the compostable component, as well as grinding operations in two stages, makes it possible to effectively separate non-ferrous scrap metal at the first stage and easily compress it for secondary use, and at the second stage, obtain a powder of inorganic inclusions in the form of particles of glass, plastic, manufacture, paper and other particles and send them for thermal decomposition in pyrolysis ny plant without environmental pollution and is almost completely clear compostable component of the inorganic, that is, to obtain high quality fertilizer.

 A method that provides integrated waste processing in environmentally friendly production with high-quality fertilizer will be widely used in industry, and therefore, the claimed technical solution meets the criterion of "INDUSTRIAL APPLICABILITY".

 The drawing schematically shows a production line for the processing of BO, illustrating the proposed method of processing waste.

 To implement the proposed method of processing BO, the processing line of the waste recycling mini-plant contains a flyover, a receiving hopper 1 with a vibrating mesh platform with a cell of 0.6 mx 0.6 m and windows for hot air ducts, a storage box for 2 household waste larger than 0.6 m, conveyor 3 for feeding BO sizes over 0.6 m into the sorting shop, conveyor 4 for transporting BOs of size 0.6 m and less, electromagnetic separator 5, ferrous scrap receiver, conveyor 6 in the manual sorting shop, centrifugal screen 7, crusher 8 (up to 20 mm fraction), accumulator of 20 mm fraction, conveyor 9, electrodynamic separator 10, mill 11 (up to 0.07-0.1 mm fraction), conveyor 12, dielectric separator 13 (for separating inorganics - glass, plastic, manufactory, paper), inorganic receivers, conveyor 14 for the organic component, bioreceiver 15, bioreactor 16, gas holder 17, centrifuge 18.

 The technological cycle of BO processing by the proposed method is as follows.

Household waste is transported by cars along the overpass to a vibrating platform with a mesh of 0.6 mx 0.6 m in the receiving hopper 1, on which they are loosened and sorted. BOs with a size of 0.6 m or less fall into the lower section of the hopper, and with a size of more than 0.6 m they roll down into the accumulator 2 through a vibrating platform, from where they are delivered by conveyor 3 to the sorting workshop. BOs with a size of less than 0.6 m in the lower part of the receiving hopper 1 are loosened, dried by supplying hot air (120-150 ^o С) through the windows of the receiving hopper 1 and fed to the conveyor 4 with a layer of no more than 20 cm. Then, the BOs are fed to the electromagnetic separator 5, where in three steps completely freed from scrap metal. The electromagnetic separator 5 is a discharge tape with an electromagnet. Ferrous metal wastes moving on the conveyor 4, falling under the influence of an electromagnetic field, are attracted to the discharge tape of the electromagnetic separator 5 and fed to the scrap metal receiver. BO, past electromagnetic processing, are fed to the conveyor 6 from two sides of which are located workers. Workers manually select large BO from conveyor 6, namely: paper, glass containers, large cullet, plastic products, cans, rags, large non-ferrous scrap metal, and send them to the packaging workshop for recycling. Further, BO is fed to the centrifugal screen 7. Under the action of centrifugal force, the lightest objects are pressed against the walls of the screen, and heavy objects - stones, sand, gravel are dumped through the center of the screen for use, for example, in road construction. Then, the BO is fed to the crusher 8, arranged according to the method of tear-breakdown type, where the BO are torn by shafts and broken into a pin to a fraction of no more than 20 mm and fall through a grid with a mesh size of 20 x 20 mm into the drive, the remaining mass of the BO is fed to crushing secondly to the crusher 8. The crushed fraction of BO with a particle size of not more than 20 mm is fed into the electrodynamic separator 10, which removes non-ferrous scrap metal from the conveyor. Three electrodynamic separators 10 are installed for more thorough cleaning of non-ferrous scrap metal from the scrap metal. Then, the secondary electrodes are fed to the mill 11, where they are ground to a fraction of 0.07-0.1 mm in size and fed into the dielectric separator 13, which creates a diamagnetic field, in powder form. BO are polarized. Polarized particles of glass, plastic, manufactory, paper and other inorganics are expelled from the bulk of the BO and fed to conveyors for further transportation to the pyrolysis workshop for thermal decomposition. The purified organic component of BO is fed to the composting workshop for processing, namely: it is mixed with water in a bioreceiver 15 and fed to the bioreactor 16 for processing into a fertilizer to obtain biogas entering the gas tank 17. To obtain fertilizer convenient for transportation, moisture is removed from it using centrifuges 18.

Claims (8)

 1. A method for processing household waste, including dividing the source material by fractional composition into sieve and under-sieve fractions, extracting ferrous and non-ferrous scrap metal from the separated fractions and subsequent processing of the separated fractions, characterized in that the separation on the screen by fractional composition is carried out in hot streams air with simultaneous drying and loosening of waste, the subsequent processing of the oversize fraction is carried out by manual sorting, and the processing of the sub-sieve fraction The operations are carried out by initial extraction of ferrous metals, manual sorting to separate paper, plastic, glass containers, textiles, large cullet, cans, rags, large non-ferrous scrap metal, separation of stones, sand, gravel, crushing to a fraction of not more than 20 mm on a centrifugal screen, extraction of non-ferrous metal, grinding to a fraction of 0.07-0.1 mm, removing particles of glass, plastic, manufactory, paper and feeding them to pyrolysis, composting the remaining organic component to obtain an environmentally friendly product rhenium and biogas.  2. The method according to p. 1, characterized in that the separation according to the fractional composition of the oversize and sublattice fractions is carried out on a screen with a mesh size of 0.6 mx 0.6 m 3. The method according to p. 1, characterized in that the separation on the screen according to the fractional composition is carried out in streams of air heated to 120-150 ^o C.  4. The method according to p. 1, characterized in that the extraction of ferrous metals from the under-sieve fraction is carried out in three stages by an electromagnetic separator, made in the form of a discharge tape with an electromagnet.  5. The method according to p. 1, characterized in that the crushing of the under-sieve fraction to a particle size of not more than 20 mm is carried out on crushers of the tacking-center type.  6. The method according to p. 1, characterized in that the extraction of non-ferrous metals from the crushed sublattice fraction with a particle size of not more than 20 mm is carried out in three stages on an electrodynamic separator.  7. The method according to p. 1, characterized in that the grinding of the under-sieve fraction to a particle size of 0.07-0.1 mm is carried out in a mill.  8. The method according to p. 1, characterized in that the removal of particles of glass, plastic, manufactory, paper and other inorganics from the fraction with a particle size of 0.07-0.1 mm is carried out in a dielectric separator.