RU2774418C1 - Method for solid municipal waste treatment - Google Patents

Abstract

FIELD: waste treatment.

SUBSTANCE: invention relates to the processing of garbage for use as fuel for combustion in power plants and can be implemented for the use of waste as a classified solid fuel or its component, and also as an alternative fuel in cement production. The method for municipal solid waste treatment is characterized by the fact that after negative and positive sorting of municipal solid waste, the remains of sorting larger than 100 mm and screening particles smaller than 100 mm are fed into the device for biothermal drying of waste by composting. After biothermal drying, the waste is sent to a screening device for separation into two fractions. The lower screening fraction obtained after separation with a size of less than 50 mm, which is an aerobically stabilized screening particles with an organic matter content of less than 10%, is sent for burial (disposal), and the upper screening fraction, a solid fuel component is fed to a grinding device, where the fractional composition of solid fuel from municipal solid waste with a humidity of 20% and less required by the customer is achieved. Before feeding to the grinding device, the upper fraction of the screening, the solid fuel component is fed to a magnetic separator to remove metal inclusions. At the same time, the size of the upper screening fraction after separation is more than 50 mm, the content of organic matter in the upper screening fraction is 70% or more, ash content is less than 10%, calorific value is 10 kJ/kg or more.

EFFECT: invention provides a decrease in the humidity of waste, a decrease in its ash content, an increase in the calorific value of waste.

3 cl, 1 dwg

Description

The invention relates to the processing of waste for use as a fuel for combustion in power plants, and can be implemented for the use of waste as a classified solid fuel or its component with characteristics that comply with regulatory and technical documentation, as well as an alternative fuel in cement production [ IPC B03B 9/06, B07B 9/00, B09B 3/00, C10L 5/48, F23G 5/02].

From the prior art known METHOD OF RECYCLING OF GARBAGE, BRIQUETTED FUEL AND ADDITIVE [RU2109035, publ. 04/20/1998], which includes preliminary sorting and processing of the original waste with the separation of the soft waste fraction containing organic residues, grinding this fraction, mixing with crushed coal, adding fat-containing residues, such as bleaching earth, compacting the mixture into briquettes, their subsequent burning, with In this case, the briquetted fuel contains a mixture in equal parts by weight of crushed coal and a fraction of soft debris containing organic residues and fat-containing residues, such as bleaching earth, and an additive to burned coal contains a fraction of soft debris containing organic residues, and fat-containing residues, such as bleaching earth .

A significant disadvantage of the analog is the need to add coal or coal dust to the recycled municipal solid waste (MSW) due to the proposed method, which leads to increased emissions of carbon dioxide and sulfur, and the resulting fuel has a high ash content, which does not allow fuel to be burned as efficiently as possible.

The prior art known METHOD OF MANUFACTURING FUEL FROM SOLID MUNICIPAL WASTE [RU2729638, publ. 08/12/2020], including the acceptance of initial MSW, their sorting with screening of non-combustible fractions, such as batteries, stones, building materials waste, cullet and ceramics, street estimates, food waste, leaves, etc., recovery of secondary materials: paper, rags, plastic, including ferrous and non-ferrous metals, grinding of the remaining wet combustible mass, its drying, further heating and thermoplastic extrusion, characterized in that the remaining combustible mass with a moisture content of more than 15% is preliminarily dehydrated in screw presses, roller presses, dryers or in another way to moisture content 5÷15%, crushed to a fraction of 5÷50 mm, heated to a temperature of 180÷250°C and subjected to thermoplastic extrusion to obtain fuel pellets or briquettes, and the water vapor and gaseous products escaping during the heating of the combustible mass are subjected to cleaning from the contents contained in them hydrogen halides. The technical result consists in increasing the physical and mechanical strength of the obtained solid (RDF) fuel, in increasing water absorption, in preventing the ingress of halogens into the manufactured fuel, in reducing the energy intensity of its production, as well as in improving the environmental situation, including by reducing the volume of landfills for MSW "tailings".

The disadvantage of analogue is the increased energy consumption due to the stage of heating the processed MSW mass to a temperature of 180...250°C before performing thermoplastic extrusion to obtain fuel pellets or briquettes.

The closest in technical essence is the METHOD OF OBTAINING SOLID BIOFUEL FROM SOLID MUNICIPAL WASTE [RU2749055, publ. 06/03/2021], which includes sorting MSW into two fractions, small - up to 80 mm and large - more than 80 mm, characterized by the fact that when sorting a large fraction, components of biogenic origin are selected, followed by grinding of components of biogenic origin. The technical result consists in improving the quality of the fuel due to the complete elimination of hazardous components.

The main technical problem of the prototype is increased energy consumption (drying of components after screening), as well as increased ash content (more than 10%) in combination with a low content of organic matter (less than 70%), which leads to a decrease in the efficiency of MSW use as fuel.

The objective of the invention is to eliminate the disadvantages of the prototype.

The technical result of the invention is to reduce the moisture content of the waste, reduce the ash content, increase the calorific value of the waste.

The specified technical result is achieved due to the fact that the method of processing solid municipal waste, characterized in that after the negative and positive sorting of solid municipal waste, the residues of sorting with a size of more than 100 mm and screening screening with a size of less than 100 mm are fed into the device for biothermal waste drying by composting, after which the waste after biothermal drying is sent to a screening device for separation into two fractions, while the lower screening fraction less than 50 mm in size obtained after separation, which is an aerobically stabilized screening with an organic matter content of less than 10%, is sent for disposal (utilization), and the upper fraction of screening - a component of solid fuel is fed to the grinding device, where the fractional composition of solid fuel required by the consumer is reached from municipal solid waste with a moisture content of 20% or less, characterized in that before feeding to the grinding device, the upper fraction screening action - a solid fuel component is fed to a magnetic separator to remove metal inclusions, the size of the upper screening fraction after separation is more than 50 mm, the content of organic matter in the upper screening fraction is 70% or more, the ash content is less than 10%, the calorific value is 10 kJ /kg and more.

In particular, sorting residues with a size of more than 100 mm and screening screening with a size of less than 100 mm are fed into the device for biothermal waste drying by composting method together.

In particular, sorting residues with a size of more than 100 mm and screening screening with a size of less than 100 mm are fed into the device for biothermal waste drying by composting separately from each other.

Brief description of the drawings.

In FIG. 1 shows a block diagram of the treatment of municipal solid waste.

In FIG. 1 marked: o1 - sorting residues, o2 - screening screening, 1 - device for biothermal drying of waste by composting, 1a - waste after biothermal drying, 2 - screening device, 2a - upper screening fraction - solid fuel component, 2b - lower screening fraction , 3 – magnetic separator, 3а – upper screening fraction after removal of metal inclusions, 4 – grinding device, 4а – solid fuel from municipal solid waste.

Implementation of the invention

When implementing the proposed method of MSW treatment, screening screening of MSW in case of their negative (manual or mechanical separation from the general flow of sorted MSW of hazardous waste, including organochlorine waste, the content of which in solid fuel (RDF) is limited by regulatory and technical documentation) and positive (isolation by manual or mechanized from the total flow of sorted MSW of secondary material resources, which may have consumer demand as secondary raw materials) sorting, containing a fraction of less than 100 mm, and the waste of sorting MSW, containing a fraction of more than 100 mm, separately or in a mixture, are sent for biothermal drying to a device for biothermal drying of waste by composting in accordance with the technical solution described in [RU 198939 U1, publ. 08/03/2020]. After biothermal drying, the waste is sent to a screening device for separation into at least 2 fractions, with a size of less than 50 mm and more than 50 mm. The first lower fraction is an aerobically stabilized screening with an organic matter content of less than 10%. The second (upper) screening fraction is a component of solid fuel from MSW with a moisture content of 20% or less, a fractional composition of 50 mm or more, with an organic matter content of 70% or more.

If necessary, at the outlet of the screening device, the second, upper fraction is subjected to magnetic separation to remove metal inclusions.

Further, the component of solid fuel from MSW (the second, upper screening fraction) is fed to the grinding device, where the required fractional composition of solid fuel from MSW, ordered by the consumer, is achieved.

The claimed technical solution is used for the manufacture of solid fuel from MSW with characteristics that meet the requirements of the current regulatory and technical documentation used in any solid fuel installations for generating heat, electricity, and also as an alternative fuel in cement production.

The claimed technical result is achieved through a single biothermal drying of waste by composting, which reduces the moisture content of MSW (up to 20% or less) and at the same time reduces energy consumption (compared to the prototype); due to the magnetic separation of the upper screening fraction, which removes metal inclusions and thus increases the efficiency of fuel combustion from MSW; due to the repeated screening operation for separation after biothermal waste drying, which leads to a more thorough selection of organic matter and an increase in its percentage (up to 70% or more) in the fuel, while the ash content due to screening decreases to less than 10%, which leads to increasing the calorific value of the resulting fuel up to 10,000 kJ/kg or more.

An example of achieving a technical result

To implement the proposed method, municipal solid waste (garbage from office and domestic premises, garbage and sweepings from cleaning parks and public recreation areas, waste from cleaning air ducts of ventilation systems) was fed to the screening device, where positive and negative sorting was carried out, after which screening was screened size less than 100 mm and sorting residues larger than 100 m were sent to a device for biothermal drying by composting.

After biothermal drying, the waste was sent to a screening device for separation into 2 fractions, with a size of less than 50 mm and more than 50 mm. The lower fraction was aerobically stabilized screening with an organic matter content of less than 10% (sent for disposal), the upper screening fraction is a component of solid fuel from MSW.

At the outlet of the screening device, the upper fraction was subjected to magnetic separation to remove metal inclusions, at the outlet of which a solid fuel component was obtained from household (communal waste) in accordance with GOST 33564.

Next, the upper screening fraction was fed to the grinding device, where the required fractional composition of solid fuel from MSW (classified according to GOST 33516), ordered by the consumer, was achieved, with the following characteristics:

- humidity 16%;

- ash content 7%;

- organic matter content 78%;

- calorific value of waste 16500 kJ/kg.

Claims (3)

1. A method for processing municipal solid waste, characterized in that, after negative and positive sorting of solid municipal waste, sorting residues of more than 100 mm in size and screening screenings of less than 100 mm in size are fed into the device for biothermal waste drying by composting, after which the waste after biothermal drying is sent to the screening device for separation into two fractions, while the lower screening fraction less than 50 mm in size, which is an aerobically stabilized screening with an organic matter content of less than 10%, obtained after separation, is sent for disposal (utilization), and the upper screening fraction is a component of solid fuel is fed to the grinding device, where the fractional composition of solid fuel required by the consumer from municipal solid waste with a moisture content of 20% or less is reached, characterized in that before being fed to the grinding device, the upper screening fraction - a component of solid fuel is fed to the magnet filament separator for removing metal inclusions, the size of the upper screening fraction after separation is more than 50 mm, the content of organic matter in the upper screening fraction is 70% or more, the ash content is less than 10%, the calorific value is 10 kJ/kg or more. 2. The method according to claim 1, characterized in that the sorting residues with a size of more than 100 mm and the screening screening with a size of less than 100 mm are fed into the device for biothermal waste drying by composting together. 3. The method according to claim 1, characterized in that the sorting residues with a size of more than 100 mm and screening screening with a size of less than 100 mm are fed into the device for biothermal waste drying by composting separately from each other.

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