JP2000303082A - Method for slurrying organic waste and production of slurried fuel thereby - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a slurried fuel which does not need dehydration, does not generate black smoke, is low in cost, is easily transported and stored, has a high calorific value and does not generate dust by freezing and milling an organic waste and mixing and dispersing the resultant slurry into a liquid or solid powdery auxiliary fuel. SOLUTION: An organic waste is frozen, divided and milled to give a slurry having a water content of about 80%. This slurry is mixed and dispersed, if necessary together with a surfactant, into a liquid auxiliary fuel, such as petroleum, a waste plastic oil or a waste oil, or into a solid powdery auxiliary fuel, such as a pulverized combustible waste, a carbonized pulverized combustible waste or coal. Thus, the cell membranes of an organic waste are destructed by a simple method without the necessity for heat and pressure, giving a slurried fuel. When fine air bubbles are mixed into this slurried fuel, the fuel burns completely without generating black smoke.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for slurrying organic waste and a method for producing a slurry fuel using the same.

[0002]

2. Description of the Related Art Organic wastes such as garbage and sewage sludge are disposed of by landfill, ocean dumping, incineration, etc. However, ocean dumping is prohibited, landfills are depleted, and are now in a marginal state. . In the future, the treatment of garbage and sewage sludge will have to rely on incineration and recycling. The biggest obstacle to incineration and recycling is that organic sludge is not fluid and is in a solid state despite its high water content of about 80%. This is because the sludge particles are covered with the protein film, and moisture is trapped in the film. Therefore, it cannot be dehydrated by ordinary mechanical dehydration, but merely dehydrates free water between cells. This is the biggest barrier to recycling and incineration. As a method for destroying the cell membrane, there is a swelling treatment. Japanese Patent No. 2741565 describes that sludge is formed into a slurry by the swelling treatment to be used as a fuel. This is a method of destroying the protein membrane by
There is a disadvantage that the processing cost is also high. This is not an effective method for treating waste.

[0003]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above problems, and has as its objects (1) a method of destroying a cell membrane of an organic waste by an extremely simple method without requiring heating and pressurization. Therefore, it is intended to provide a method capable of forming a slurry. Another object of the present invention is to provide (2) a novel method of breaking down a cell membrane to form a slurry to produce a slurry-like fuel.

[0004]

Means for Solving the Problems The present inventors have conducted intensive studies on the above-mentioned problems, and have obtained the following findings. That is, (1) When an organic waste such as garbage and sludge is frozen and divided and ground, the cell membrane is destroyed and the water in the membrane flows out to form a slurry. (2) An excellent slurry-like fuel can be obtained by mixing and dispersing an auxiliary fuel in the form of a liquid or a solid powder into a slurry obtained by freezing, dividing and grinding the organic waste to form a slurry. The above findings were obtained. The present invention has been made based on the above findings, and has the following configuration. (1) A method for forming a slurry of organic waste, comprising freezing the organic waste and subjecting it to fragmentation and grinding. (2) The method according to claim 1, wherein the waste is sewage sludge. (3) The method according to claim 1, wherein the waste is garbage. (4) A process for producing a slurry-like fuel, comprising the steps of freezing and grinding organic waste to form a slurry, and mixing and dispersing a liquid or solid powdery auxiliary fuel with the slurry. Method. (5) a step of freezing and grinding organic waste to form a slurry, a step of mixing and dispersing a liquid or solid powdery auxiliary fuel with the slurry, and a step of mixing and dispersing air bubbles in the slurry. A method for producing a slurry-like fuel, comprising: (6) The auxiliary fuel is waste plastic oil.
Alternatively, the slurry fuel according to 5. (7) The slurry-like fuel according to claim 4 or 5, wherein the auxiliary fuel is finely pulverized combustible waste. (8) The slurry fuel according to claim 4 or 5, wherein the auxiliary fuel is a combustible waste carbide powder. (9) The slurry-like fuel according to claim 4 or 5, wherein the auxiliary fuel is a fossil fuel.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The freezing and fragmentation of the present invention is
This means that the water in the cell membrane is frozen or semi-frozen to form fine particles by high-speed pulverization. Micronization occurs at temperatures substantially below freezing. When the microparticles with the cell membrane destroyed are thawed, the water in the membrane flows out to form a slurry.

The thawed slurry contains a maximum of about 80% of water and can be used as a fuel by itself. However, since the calorific value fluctuates greatly and the calorific value is often small, the amount of water is appropriately adjusted (reduced). In addition, it is preferable that the heat generation amount is adjusted for use. To adjust the calorific value, it is preferable to mix and disperse a liquid or solid powdery auxiliary fuel. The order of mixing may be such that the organic waste is once freeze-milled to form a slurry and then mixed, or may be added simultaneously with freeze-milling to form a slurry together.

The auxiliary fuel is preferably in the form of a liquid or solid powder. As the liquid type, petroleum, waste plastic oil, waste oil and the like are preferable, but since the oil type is difficult to mix with the slurry, it is preferable to add a surfactant to the slurry to emulsify. Ultrasonic irradiation is also effective for emulsification. Pulverized combustible waste, or finely pulverized combustible waste carbide or fossil fuel powder such as coal is preferred as the solid powdered auxiliary fuel. In order to improve the property, a surfactant may be added in an amount of 1% to several%.

The term "combustible waste" refers to all organic and inorganic combustible waste. What is inorganic combustible waste?
Refers to coal-based waste such as waste coal, waste pitch and waste coke. Organic combustible waste refers to all hydrocarbon waste. For example, shochu, salmon, beer and other various alcohols, waste vegetables, waste food, waste pulp, waste wood, waste alcohol, waste plastic, waste oil, okara, food processing residue, livestock offal, blood, feces And so on. As for these wastes, those which can be powdered are preferably directly powdered, and the others are preferably carbonized once, pulverized and powdered.

The amount of water may be adjusted by appropriate heat treatment or by mechanical dehydration or by adding water-absorbing waste such as waste paper and sawdust.

When fine air bubbles are mixed with the slurry-like fuel of the present invention, the fuel is completely burnt and the generation of graphite can be prevented.
Fine bubbles can be generated in the invention as described below, which is an invention related to the present applicant's application. In other words, by rotating the spiral plate in the slurry, a strong swirling flow is generated while sucking air to generate a strong swirling flow, finely divide the air to purify fine bubbles, and generate a slurry in which bubbles are dispersed by mixing and stirring. . The size of the bubbles can be freely adjusted to a size of 10 to several hundred microns.

[0011]

The present invention will be described by way of examples. Example 1 Preparation of slurry 1 kg of sewage sludge mechanically dewatered as organic waste as raw material
Was prepared, frozen at −30 ° C. below the freezing point, pulverized by a high-speed disintegrator, and then thawed. The solid sludge became a muddy slurry. The water content was about 80%. Next, after drying and dehydrating to 60%, 30% of waste plastic oil made by turning waste plastic (polystyrene) into oil and 5% of a surfactant are added, stirred and mixed to emulsify the oil and organic slurry to form a slurry. A fuel was prepared. Combustion test Next, this was subjected to a combustion test using a burner. Burned black smoke. The calorific value was about 7,000 Kcal.

Example 2 Raw Materials: 1. Sewage sludge mechanically dewatered as organic waste: 800 g 2. Dehydrated garbage: 200 g Waste wood, carbonized powder of waste plastic: 300 g The raw materials of 1, 2, and 3 were mixed, frozen at −30 ° C., crushed with a high-speed cutting and grinding machine, and then thawed. A muddy slurry was obtained. Next, 50 to 100 micro micro bubbles were mixed and dispersed in the slurry, and this was subjected to a combustion test using a burner. There was almost no generation of graphite. The calorific value is 5000
Kcal.

Example 3 Raw Materials: 1. Sewage sludge mechanically dewatered as organic waste: 800 g 2. Heavy oil: 100 g Waste coal powder: 100 g A small amount of a surfactant was mixed with the raw materials of 1, 2, 3 and frozen at -20 ° C, followed by grinding with a high-speed cutting and grinding machine, followed by thawing. A muddy slurry was obtained. Next, it was burned using a burner. The calorific value was 4000 Kcal.

[0014]

According to the present invention, as described in detail above, an organic waste such as sludge which is in trouble in a dumping place and is in trouble can be slurried and converted into a fuel by a simple method. And high level of calorific value Inexpensive and easy to transport and store Low generation of black smoke during combustion. There is no generation of dust. It has features such as no need for dehydration and makes a great contribution to waste reduction and resource recycling.

Claims (9)

[Claims] 1. A method for preparing a slurry of organic waste, comprising freezing the organic waste and subjecting it to fragmentation and grinding. 2. The liquefaction method according to claim 1, wherein the waste is sewage sludge. 3. The liquefaction method according to claim 1, wherein the waste is garbage. 4. A slurry-like fuel comprising a step of freezing and grinding an organic waste to form a slurry, and a step of mixing and dispersing a liquid or solid powdery auxiliary fuel with the slurry. Manufacturing method. 5. A process for freezing and grinding organic waste to form a slurry, a process for mixing and dispersing a liquid or solid powdery auxiliary fuel with the slurry, and a process for mixing and dispersing air bubbles in the slurry. A method for producing a slurry-like fuel, comprising a step. 6. A slurry fuel according to claim 4, wherein said auxiliary fuel is waste plastic oil. 7. The slurry fuel according to claim 4, wherein the auxiliary fuel is finely pulverized combustible waste. 8. The slurry fuel according to claim 4, wherein the auxiliary fuel is a combustible waste carbide powder. 9. The slurry fuel according to claim 4, wherein the auxiliary fuel is a fossil fuel.