RU2537199C2 - Treatment of solid household wastes of vegetable origin - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to processing of solid domestic wastes with organic components. Proposed process comprises collection of wastes and their transfer to processing site, sorting and processing. Wastes are sorted by size and composition grading to coarse wood wastes, fine wood wastes and greenwood. Various inclusions are removed from household wood wastes. Moisture content is measured. Wastes with moisture content less than 20% are directly sent to grinding. Those with moisture content over 20% are subjected to drying. After adequate drying, these are directed to grinding. Moisture content of wood chips is measured. In case it is over 20%, said chips are dried and, thereafter, sorted to sizes and applications.

EFFECT: higher efficiency of processing and quality of produced chips, lower costs, non-polluting process.

6 cl, 2 dwg

Description

FIELD OF THE INVENTION

The invention relates to the field of processing of solid household waste (MSW) containing organic components, and can find application in utilities, energy, agriculture and other industries.

State of the art

MSW from the residential sector is divided into bulky waste and small waste that is collected in garbage containers and transported by garbage trucks to the MSW landfill. Bulky waste that is part of solid waste in the winter season is from 10 to 15% in the residential sector, which is built up with multi-story buildings, and 15-20% in the summer. In the residential sector, built up by private households, bulky waste is greater due to waste from household plots, their amount is from 10 to 15% in winter and from 25 to 35% in other seasons. In terms of morphological composition, bulky waste consists almost 95% of organic waste, 3% - metals from dismantling household appliances and 2% other waste to be disposed of in a landfill. Of the organic waste, about 80% is plant waste (tree trimmings, fallen leaves, tops from household plots). These wastes are also disposed of for landfill for disposal of solid waste, which are usually located at a considerable distance from the places of collection of solid waste.

There are various ways of processing household waste: accumulation at landfills and their natural decomposition with partial burning in the open air; alloy crushed household waste into the sewer; processing waste into compost and biofuel; waste incineration, etc.

There is a method of processing household waste (RF patent for the invention No. 2048462, C05F9 / 00, published on November 20, 1995), in accordance with this method, household waste is dried at a temperature of 75-105 ° C, metal inclusions are removed and pressed into bales. The remaining mass of household waste is crushed to the size of coarse sand, mixed with water and passed through sand traps. Then components that are heavier than water are removed from the sand trap and bricks and blocks are formed from them in a mixture with cement. Floating organic matter is passed through an arc sieve, mixed with sewage sludge, treated, treated, filled with oxygen in the air and organic fertilizers are prepared. Water with dissolved organic matter from the sand traps and arc sieves is sent to the sump, after which it is reused in the sand traps, and the sediment is mixed with the primary material descended from the arc sieves and with sewage sludge.

The disadvantage of this method is that the performance of such technology is limited, the technology is energy intensive, requires a large amount of electricity to be sold.

A known method of processing household waste (RF patent for the invention No. 2238156, B09B3 / 00, B03B9 / 06, C05F9 / 00, publ. 20.10.2004), including the preliminary extraction of bulky waste from the waste, followed by the supply of waste loading conveyor into the primary rotating drum in which the moving waste is loosened at the same time and the bags and bags with waste are destroyed, the waste coming from the rotating drum is transported by means of a sorting conveyor to the main sorting for sequential extraction of various fractions waste, which is transferred for recycling, and the preliminary removal of bulky garbage before transferring the waste to the loading conveyor is carried out at the storage sites of the pre-sorting unit, and before the main sorting, the waste is heated to a temperature of 150-250 ^° C for 15-40 minutes in a rotating rotary drum for their disinfection.

The disadvantage of this method of processing household waste is the relatively high complexity of the recycling process and high energy costs.

A known method of processing solid waste (RF patent for the invention No. 2158636, B02C21 / 00, B09B3 / 00, publ. 10.11.2000), including the simultaneous grinding, mixing and drying of waste at a temperature of 150-790 ^° C in the ventilated space of a ball mill with grinding the bodies of the mill.

The disadvantage of this method is the fact that the grinding of waste during drying by grinding media simultaneously with exposure to high temperature reduces the efficiency of extraction of useful products and leads to the fact that small parts of plastics, glass and other components fall into the compost. In addition, the high drying temperature of up to 790 ^° C contributes to the combustion of many components included in the waste, as a result of which the goal of complete processing of the waste into recycled raw materials is not achieved.

A known method of processing solid household waste (USSR author's certificate No. 1616720, B07 B1 / 22, publ. 12/30/1990), including the collection of waste and their transportation by garbage trucks to a sorting station, pre-sorting by transferring waste from garbage trucks to a loading conveyor, followed by sorting into rotating drum screen, the main sorting into fractions of waste coming out of the screen, and the processing of materials obtained after sorting.

In the known method, large items, bags and bags of waste passing through the screen are not removed from the waste loaded into the drum screen, and as a result, after preliminary sorting, excess ballast materials are found in the waste leaving the screen, which also reduces efficiency of sorting into separate fractions.

The closest to the claimed technical solution for the combination of essential features and purpose is a method for the processing of municipal solid waste (RF patent for invention No. 2155108, B09B3 / 00, published on 08.27.2000), including waste collection and transportation by garbage trucks to a marshalling yard, preliminary sorting by transferring waste from garbage trucks to a loading conveyor, followed by sorting in a rotating drum screen, main sorting into fractions of waste coming out of the screen, and processing materials, floor after sorting, and large-sized items are removed from the waste transported by the loading conveyor, the waste is loaded into the rotating perforated cylinder of the drum screen, inside the screen, the waste is moved along spiral paths by means of the auger blades located in the screen, and at the same time, the transported waste loosens and destroys the bags and bags with waste, during the main sorting, the waste is transported by means of a sorting conveyor and various fractions are extracted from the transported waste, while the fraction consisting of non-utilizable waste is transferred to unloaded garbage trucks.

The disadvantage of this method is the relatively low efficiency of the technological process of processing, as well as obtaining products with low quality characteristics.

Disclosure of invention

The objective of the invention is to provide a simple and reliable method of processing solid household waste of plant content, which allows to obtain useful materials for humans from household waste: fuel, fertilizers, etc., which provides, inter alia, environmental protection.

The technical result of the present invention is to increase the efficiency of technological operations of processing solid waste, as well as improving the quality characteristics of the resulting chips; reduction of expenses for cleaning up natural dumps, obtaining alternative fuel from solid waste used for heating own production facilities; reduction of environmental stress in the area; ensuring high production ecology; exclusion of greenhouse gas emissions during landfill disposal.

The specified technical result is achieved by the fact that in the known method of processing waste of plant content, including collecting waste and transporting it to a site for processing solid household waste, sorting and processing waste, according to the invention, sorting is carried out by size and composition: large household wood waste, small wood waste and freshly sawn wood; various kinds of inclusions are removed from household wood waste; then they measure the humidity of the waste, and waste having a moisture content of less than 20% is sent directly to crushing, and having a moisture content of more than 20% is sent to drying; upon reaching the required humidity value, the dried waste is sent to grinding; then measure the moisture content of wood chips; if the moisture content of wood chips exceeds 20%, it is sent for drying; after which the chips are sorted by size and purpose.

Drying of solid household waste can be carried out naturally in a waste treatment area under a canopy or in a multi-tiered mesh rack.

Drying of solid household waste can be carried out by forced accelerated drying at a temperature of 75-100 ^° C.

It is possible to dry wood chips due to the hot water circuit passing inside the drying bin.

The movement of wood chips and sawdust during processing is carried out using conveyor belts.

Brief Description of the Drawings

In FIG. 1 shows a process flow diagram of a method for processing municipal solid waste of plant content.

In FIG. 2 shows a functional diagram of a site for the processing of municipal solid waste of plant content.

The implementation of the invention

In FIG. 2 the following designations are accepted: process receiver 1, site for receiving bulky waste 2, platform with a canopy for natural drying 3, device for forced accelerated drying 4, crusher 5, receiving hopper 6, drying hopper 7, warehouse 8, boiler 9, truck 10 , MSW 11.

The receiving hopper 6 is intended for the accumulation of crushed chips, as well as for measuring moisture and sorting chips. In the drying hopper 7 is forced drying of chips with a moisture content of more than 20%.

A method of processing municipal solid waste of plant content is as follows.

Oversized solid household waste stored by the population near the container sites is taken to the waste treatment site 2. The waste treatment site 2 has a solid waterproof coating with cut-off concrete borders around the perimeter on three sides. From the end of the fourth side, the site goes into a technological pit for collecting waste that has not undergone processing and is subsequently sent to the landfill. The technological pit has dimensions of 5 m in length and 2 m in width, depth is not more than 0.45 m. Site 2 has a rectangular configuration, its area is determined based on 9 square meters for receiving 6-8 cubic meters of waste. For example, a site measuring 9 m in width and 18 m in length allows you to accumulate up to 100 cubic meters of waste at a time, which ensures the implementation of an uninterrupted technological process for the disposal of solid waste.

Waste 11 from trucks 10 (dump trucks) is unloaded in rows along the length of platform 2. At site 2, the sorting of solid waste is carried out. The sorted bulky waste by morphological composition is distinguished by the quantitative ratio of plant waste from the household plot and waste from dwellings. Spring, summer and autumn - the time of the greatest amount of waste of plant content, such as pruning of trees, shrubs, etc. Sorting is carried out by size and composition: for large household wood waste (furniture), small wood waste and freshly sawn wood. From household wood waste - furniture - remove inclusions of various kinds (metal, plastic, etc.). Then a moisture measurement is carried out, waste having a moisture content of less than 20% is sent directly to crushing.

If the moisture content of solid waste is more than 20%, they are dried. Various drying options are possible: natural drying on a platform with a canopy 3 or, for example, on a multi-tiered mesh rack. For high air humidity or in the cold season, forced accelerated drying can be carried out at a temperature of 75-100 ^° C using a forced drying device 4 (infrared heater, "heat gun", etc.). Upon reaching the required humidity value (determined by a control measurement of moisture), the dried waste is sent to the crusher 5, in which the waste is crushed into chips.

Then, the crushed chips enter the receiving hopper 6, in which they also measure the moisture content of the chips and sort them by size and purpose. Sorting chips can be carried out using a metal mesh with different cell sizes.

If the moisture content of the chips exceeds 20%, it is sent to a drying bin 7, in which the chips are forced to dry. Drying of wood chips occurs due to the hot water circuit passing inside the hopper 7, connected to the heating system from the boiler. The movement of wood chips and sawdust during the process is carried out using conveyor belts.

Wood chips can then be used to heat their own production facilities, and wood chips can also be used to make compost, fuel briquettes, pellets, in the process of making animal skins, etc.

The described method for the processing of bulky solid waste can be fully applied for landscaping (utilization of felled trees, cleaning of natural dumps, etc.). The cost of material costs for the construction and launch of such processing of municipal solid waste of plant content is minimal.

Thus, the claimed method ensures the achievement of the claimed technical result, namely, increasing the efficiency of technological operations of processing solid waste, improving the quality characteristics of the resulting chips; reduction of costs for cleaning up natural dumps; obtaining alternative fuel, the ability to manufacture composite materials (wood-polymer). The claimed processing method also provides a reduction in environmental stress; ensuring high production ecology; exclusion of greenhouse gas emissions during landfill disposal.

Claims (6)

1. A method of processing waste of plant content, including collecting waste and transporting it to a site for processing solid household waste, sorting and processing waste, characterized in that the sorting is carried out by size and composition: large household waste wood, small wood waste and freshly sawn wood , various inclusions are removed from household wood waste, then the moisture content of the waste is measured, and waste having a moisture content of less than 20% is sent directly to the fraction pouring, and having a humidity of more than 20% - for drying, upon reaching the required humidity value, the dried waste is sent for grinding, then the moisture content of wood chips is measured, if the moisture content of wood chips exceeds 20%, it is sent for drying, and then sorted wood chips in size and purpose. 2. The method according to claim 1, characterized in that the drying of municipal solid waste is carried out naturally at the site for processing waste under a canopy. 3. The method according to claim 1, characterized in that the drying of municipal solid waste is carried out naturally on a multi-tiered mesh rack. 4. The method according to claim 1, characterized in that the drying of municipal solid waste is carried out by forced accelerated drying at a temperature of 75-100 ° C. 5. The method according to claim 1, characterized in that the drying of wood chips is carried out due to the hot water circuit passing inside the drying hopper. 6. The method according to claim 1, characterized in that the movement of wood chips and sawdust during processing is carried out using conveyor belts.

Images