KR20030080701A - Method for manufacturing refuse derived fuel in soild state which comprises food waste containing grain and vegetable, general waste containing paper and plastic, and coals - Google Patents

Abstract

PURPOSE: A method for manufacturing refuse derived fuel (RDF) comprising garbage including grain and vegetables, general waste including paper and plastics, and coal is provided, wherein starch is used to keep the shape of RDF at low price. CONSTITUTION: The method comprises first step of producing a pressed garbage material by pressing garbage including grain and vegetables; second step of producing crushed garbage material by cutting the pressed garbage material; third step of producing pressed general waste material by pressing general waste including paper and plastics; fourth step of producing crushed general waste material by cutting the pressed general waste material; fifth step of mixing the crushed garbage material, crushed general waste material and coal; sixth step of producing first solid fuel molded article by press molding the mixture of the fifth step; seventh step of producing dried first molded article by heating the first molded article of the sixth step; and eighth step of producing final solid fuel by cutting the dried molded article to a size capable of being poured into burner.

Description

Method for manufacturing refuse derived fuel in soild state which comprises food waste containing grain and vegetable, general waste containing paper and plastic, and coals}

The present invention relates to a waste recycling method, and more particularly, to a method for producing agricultural solid fuel containing coal and food waste containing grains and vegetables, general waste including paper and plastics.

Domestic waste generation has decreased greatly in the early stages of the introduction of the waste-based tax system in 1995, but has recently increased gradually. Food waste has also continued to decline, but the decline is slowing. In particular, the share of food waste in household waste still exceeds 25%, regardless of the increase or decrease in domestic waste generation (see Table 1).

(Unit: ton / day) division 1994 1995 1996's 1997 1998 1999 2000's Domestic Waste Generation 58,118 47,774 49,925 47,895 44,583 45,614 46,438 Food Waste Generation 18,055 (31%) 15,075 (31%) 14,532 (29%) 13,063 (27%) 11,798 (26%) 11,577 (25%) 11,434 (25%)

In terms of occurrence, most food wastes occur in general households, followed by restaurants. However, in terms of the amount generated per capita, the amount of food emitted from restaurants is eight times higher than that of households, which can cause serious food waste problems in restaurants. By nature, vegetables account for 46%, cereals 22%, fish meat 16%, and fruits 16%. [Yoo Ki-young, "Reduction of Food Waste and Resources," Seoul Development Institute, 1997, p 15]. Table 2 shows the percentage of food waste generated by each source.

division home Restaurants (including retailers) Composition ratio 53% 47% Amount per person (kg / day) 0.3 2.3

On the other hand, with the emission sources, the rate of outbreaks at restaurants and retailers rather than at home is expected to increase with the development of the food culture and distribution industry.

As of the end of 2000, the amount of food waste generated daily is 11,434 tons, which is about 1,400 units in 8 tons of large trucks, and it costs 400 billion won to process them. In particular, when burying food waste, odor may occur, and leachate may cause secondary environmental pollution such as inhibition of landfill stabilization and soil pollution and insect breeding.

Therefore, it is a mission of the times to recycle food waste, which is inevitably generated, despite various reduction efforts.

A method for composting or feeding food wastes is disclosed in Korean Unexamined Patent Publication No. 2001-0029297 as one of the recycling methods of food waste.

On the other hand, as a prior art regarding recycled fuel, a method of producing waste induction fuel containing waste sludge and waste paper and waste plastic, such as sewage sludge generated in a sewage terminal treatment plant, is disclosed in Korean Patent Laid-Open No. 2001-0087835.

There are a number of prior arts relating to other food waste recycling methods and methods for producing recycled fuels, but to date, there have been no techniques for producing recycled solid fuels containing food wastes suitable for use as low cost fuel for agriculture.

Therefore, the present invention includes food waste containing grains and vegetables, general waste including paper and plastics, and coal, in order to obtain food waste resources and low-cost fuel for agriculture, and by starch components included in the food waste. It is intended to provide a method of manufacturing recycled solid fuel that maintains shape by bonding force.

1 is an overall configuration diagram of an exemplary facility for realizing the recycled solid fuel production method of the present invention.

In order to solve the above technical problem, the present invention, the first step of producing food waste compacted by compressing food waste containing grains and vegetables, the first step of cutting the food waste compacted to produce a food waste crushed A second step of compressing the general waste including paper and plastic to produce a general waste compact, a fourth step of cutting the general waste compact to generate a general waste pulverized product, the food waste pulverized product, A fifth step of mixing the general waste pulverized product and coal, and a sixth step of compressing the mixture of the fifth step to produce a compression molded product, and heating the compressed product of the sixth step to produce a dried compressed product. Step 7 and the recycled solid completed by cutting the dried compact into a size that can be put into the combustor It provides a recycling method of producing a solid fuel, comprising an eighth step of generating a charge.

On the other hand, the sixth step and the seventh step may be performed at the same time to simplify the manufacturing apparatus.

In addition, the drying of the seventh step is preferably carried out at a temperature of 100 to 600 ℃.

Moreover, it is preferable that the coal used for the said manufacturing method is powder coal.

In addition, the mixing ratio of the food waste in the recycled solid fuel in the manufacturing method is 20 to 45% by weight, the mixing ratio of the general waste in the recycled solid fuel is 25 to 60% by weight, and the mixing ratio of coal in the recycled solid fuel is 20 It is preferable to make it to 50 weight%.

In addition, the form of the primary molded product produced in the seventh step of the manufacturing method is preferably selected from hollow park mold, hollow triangle pillar, hollow fiber pillar, hollow hexagon pillar and hollow octagon pillar.

In addition, it is preferable that the primary molded product has an outer diameter of 5 to 15 cm and an inner diameter of the hollow portion of 2 to 6 cm.

In addition, the final solid fuel produced in the eighth step of the manufacturing method is preferably cut to have a size of 10 to 30 cm in length.

In addition, the present invention is a solid fuel produced by the above production method, the solid fuel maintains the shape by the binding force by the starch component contained in the food waste, the compressive strength is 0.1 to 1 ㎏ / ㎠, low The calorific value provides a recycled solid fuel, characterized in that 1000 to 6000 kcal / kg.

Hereinafter, the technical configuration of the present invention through the preferred embodiment of the present invention with reference to the accompanying drawings will be described in detail.

1 is an overall configuration diagram of an exemplary facility for realizing the recycled solid fuel production method of the present invention. The facility is a waste compression / cutting machine (1) for compressing / cutting food waste and / or general waste, a conveying conveyor (3) for moving the compressed / cut waste to the next step, mixing the compressed / cut waste and coal Mixing tank (9), coal conveyor (5) for transporting coal to mixing tank (9), coal storage tank (7) for storing coal in powdered coal form, compression molding dryer (11) for compression molding and drying mixture Compression molding machine 13 for cutting the dried compressed molding to a predetermined size, and a finished fuel discharge conveyor 15 for conveying the finished recycled solid fuel.

The general waste including food waste and food and plastics separated and discharged mainly from restaurants is put into a trash compactor / cutter (1) and is converted into trash waste on assembly. In this case, food waste and general waste may be crushed through separate waste compression / cutting machines because the strengths are different from each other.

The waste pulverized product is introduced into the mixing tank 9 through the transfer conveyor 3. In addition, coal in the form of powdered coal is introduced into the mixing tank 9 through the coal conveyor 5 from the coal storage tank (7).

The waste pulverized matter and the powdered coal are uniformly stirred in the mixing tank 9 and then moved to the compression molding dryer 11 under the mixing tank 9. The mixture is compression molded by a screw in the compression dryer 11 and dried by a heating device attached to the compression dryer 11 while passing through the compression dryer 11. At this time, the drying temperature is preferably 100 to 600 ℃. In addition, in order to increase the combustion performance of the recycled solid fuel, by changing the shape and size of the nozzle of the compression molding dryer (11), the shape of the compression molded product in the hollow park mold, hollow triangle pillar, hollow fiber pillar, hollow hexagon pillar and hollow octagon The outer diameter of the compression molded product may be selected from the pillars, and the inner diameter of the hollow portion may be 2 to 6 cm.

The dried compacts are cut into sizes suitable for use in combustion as they pass through the compacts cutter 13 to become a finished recycled solid fuel. The completed recycled solid fuel is discharged out of the facility through the finished fuel discharge conveyor (15). At this time, the finished recycled solid fuel is preferably cut to have a length of 10 to 30 cm in size.

On the other hand, in the manufacturing method of the present invention, in order to ensure that the recycled solid fuel has an appropriate calorific value and maintains its proper strength in use, the mixing ratio of the food waste in the recycled solid fuel is 20 to 45% by weight, and the amount of general waste in the recycled solid fuel Preferably, the mixing ratio is 25 to 60% by weight and the mixing ratio of coal in the recycled solid fuel is 20 to 50% by weight. Accordingly, the low calorific value of the recycled solid fuel according to the manufacturing method of the present invention is about 1000 to 6000 kcal / kg.

In addition, the manufacturing method of the present invention may further comprise the step of introducing a lime component to neutralize the SOx, NOx components in the exhaust gas generated during the combustion of the recycled solid fuel, the lime component of the recycled solid fuel The content is preferably 2 to 5% by weight. The lime component may be introduced into the mixing tank 9 in the above embodiment.

In addition, the recycled solid fuel produced according to the production method of the present invention has a compressive strength sufficient to maintain its shape when transported / handled by a binding force of starch contained in food waste, without any binding material. In practice, the numerical value exhibits about 0.1 to 1 kg / cm 2.

Example

By using the equipment according to the preferred embodiment of the present invention, the hollow waste plastic recycled solid fuel sample having a diameter of 9 cm, a hollow portion of an inner diameter of 3 cm, and a length of 20 cm, varying in general waste, food waste and coal content. The compressive strength and low calorific value were measured, and the results are shown in Table 3.

Food waste (% by weight) General garbage (% by weight) Coal (wt%) Compressive strength (㎏ / ㎠) Low calorific value (㎉ / ㎏) grain vegetable Etc paper plastic Etc 7 10 8 20 5 10 40 0.5-1.0 2000 ~ 3000 5 10 10 25 7 8 35 0.4 ~ 0.8 1500-2000 5 13 12 25 7 8 30 0.3 ~ 1.0 1200-1700 5 13 12 28 9 8 25 0.1 1000-1500

By using the method of the present invention, the food waste containing grains and vegetables, the general waste including paper and plastics and coal, and the shape of the transport / handling by the binding force by the starch component contained in the food waste It is possible to obtain a recycled solid fuel having a compressive strength suitable for maintenance and having a calorific value suitable for use as a low-cost fuel for agriculture, and at the same time to achieve the recycling of food waste and general garbage.

In the present specification, the present invention has been described with reference to limited embodiments, but various embodiments are possible within the spirit of the present invention, and equivalent means will be referred to as being combined with the present invention. Therefore, the true scope of the present invention will be defined by the claims.

Claims (9)

A first step of compressing food waste containing grains and vegetables to produce food waste compacts; A second step of cutting the food waste compact to produce a food waste crushed product; A third step of compressing the general waste including paper and plastic to produce a general waste compact; A fourth step of cutting the general waste compact to produce general waste pulverized product; A fifth step of mixing the food waste ground product, the general waste ground material and coal; A sixth step of compression molding the mixture of the fifth step to produce a solid fuel primary molding; A seventh step of producing a dried primary molded product by heating the primary molded product of the sixth step; And And a eighth step of cutting the dried primary molded product into a size that can be injected into a combustor to produce a final solid fuel. The method of claim 1, wherein the sixth step and the seventh step are performed at the same time. The method of claim 1, wherein the drying of the seventh step is carried out at a temperature of 100 to 600 ℃. The method of claim 1, wherein the coal is a powdered coal production method. The mixing ratio of the food waste in the recycled solid fuel is 20 to 45% by weight, the mixing ratio of the general waste in the recycled solid fuel is 25 to 60% by weight, and the mixing ratio of the coal in the recycled solid fuel is 20. Method for producing a solid fuel, characterized in that from about 50% by weight. The method of claim 1, wherein the form of the primary molded product produced in the seventh step is selected from hollow park moulds, hollow triangular prisms, hollow fiber prisms, hollow hexagonal prisms, and hollow octagonal prisms. . 7. The method of claim 6, wherein the primary molded product has an outer diameter of 5 to 15 cm and an inner diameter of the hollow portion of 2 to 6 cm. The method of claim 1, wherein the final solid fuel produced in the eighth step has a size of 10 to 30 cm in length. The solid fuel according to any one of claims 1 to 8, wherein the solid fuel maintains the shape by the binding force by the starch component contained in the food waste, the compressive strength is 0.1 to 1 kg / ㎠, low Calorific value is a recycled solid fuel, characterized in that 1000 to 6000 kcal / kg.