KR20100032221A - Apparatus and method for disposing organic waste to utilize methane gas - Google Patents

Abstract

PURPOSE: An organic waste processing device utilizing methane gas and a method thereof are provided to utilize methane gas energy naturally produced in a digestion and fermentation process in different uses by processing and fermenting wastewater. CONSTITUTION: An organic waste processing device utilizing methane gas comprises the following: a sewage processing tank(10) in which sewage is stored; a digestion and fermentation tank(20) processing the sewage discharged from the sewage processing tank; and a heat pump(30) discharging the sewage by lowering temperature of the sewage. The heat pump includes a compressor(31), a first heat exchanger(32), an expansion side(33), and a second heat exchanger(34).

Description

Organic waste disposal apparatus and method for utilizing methane gas {APPARATUS AND METHOD FOR DISPOSING ORGANIC WASTE TO UTILIZE METHANE GAS}

The present invention relates to an organic waste treatment apparatus for utilizing methane gas, and more specifically, when treating sewage by anaerobic reaction, the sewage temperature may be adjusted to an appropriate temperature without operating a separate boiler. The present invention relates to an organic waste treatment apparatus and method for utilizing methane gas, which can be used for drying solid sewage sludge by energizing methane gas generated during fermentation by an anaerobic reaction.

At present, organic waste treatment methods for utilizing methane gas used in factories and livestock farms have been attempted to be composted by high-speed fermentation. However, in the case of composting, Korean food waste has a large amount of salinity. Loss of value as compost due to poor permeability, poor absorption of roots, and acidification of soil due to chlorine enrichment.For feed, the feed content of nutrients such as crude fat, crude protein, crude fiber, and crude ash is above a certain ratio. Due to legal regulations, heavy metals such as arsenic, mercury, and apritoxins, there are definite limits for hazardous substances, and due to problems such as incorporation of these substances, difficulties in anti-corruption, imbalance of calories, and moisture content relations, it is impossible to obtain active responses from farms and livestock. Organic to utilize methane gas Sexual waste disposal systems are limited to small-scale treatment technologies, but are lacking in technologies and methods for large-capacity treatment.

Recently, a technique for treating organic waste by anaerobic methods has been commercialized.

As shown in FIG. 1, in the method of treating organic waste by an anaerobic method, wastewater generated in a sewage treatment plant 1 is introduced into a digester 2, and the internal temperature of the digester 2 is adjusted by a boiler 3 to a proper temperature. It is maintained at (approximately 50 ° C.) and fermented. At this time, methane gas generated by methane bacteria is produced in the digester 2.

Conventionally, by operating the boiler 3 by energizing methane gas generated in the digester 2, the effect of reducing the cost of operating the boiler 3 is derived.

According to the conventional technology configured as described above, although the methane gas naturally generated in the digester 2 is energized without disposal, there is an advantage in terms of recycling and cost of waste resources, but only the operation of the boiler 3 is carried out. Since it is used, the utility of methane gas is falling.

For example, the above-described technology is limited to wastewater, and solid sewage sludge is dumped at sea because it has no special treatment technology and is not legally regulated. However, due to the severe environmental pollution caused by the sewage sludge's ocean dumping, the law prohibiting the sewage sludge's ocean dumping will be passed, and it will be implemented soon, and if methane gas energy is applied to the technology such as the composting of sewage sludge, environmental pollution However, it is possible to derive big expected effects in terms of cost.

The present invention is to solve the above problems, the wastewater generated in the sewage treatment plant is heated to an appropriate temperature and fermented by an anaerobic method, wherein the heat source of digestive fermentation is replaced by a heat source other than methane gas energy to extinguish It is an object of the present invention to provide an organic waste treatment apparatus and method for utilizing methane gas, which can use methane gas energy generated naturally during fermentation for other purposes.

Organic waste treatment apparatus for utilizing the methane gas according to the present invention for achieving the object as described above, the sewage treatment tank is stored sewage; A digestive fermentation tank for anaerobic treatment of sewage discharged from the sewage treatment tank; It includes a heat pump to increase the temperature of the sewage discharged from the sewage treatment tank to enter the digestive fermentation tank, and to lower the temperature of the waste water passed through the digestive fermentation tank to discharge the discharge, the heat pump, by the compressor, the compressor A first heat exchanger for exchanging the refrigerant compressed at high temperature and high pressure with the sewage discharged from the sewage treatment tank, an expansion valve for depressurizing the refrigerant passing through the first heat exchanger, and the refrigerant decompressed by the expansion valve and the fire extinguishing tank Characterized in that it consists of a second heat exchanger for heat exchange of the waste water.

In addition, the organic waste treatment method for utilizing the methane gas according to the present invention comprises a first step of raising the temperature of the sewage by heat-exchanging the refrigerant passing through the first heat exchanger of the sewage and the heat pump; A second step of putting anaerobic fermentation into the digestive fermentation tank by introducing the sewage whose temperature is increased by the first step; And a third step of lowering the temperature of the wastewater by exchanging heat with the refrigerant passing through the second heat exchanger of the wastewater and the heat pump.

According to the organic waste treatment apparatus and method for utilizing the methane gas according to the present invention, a separate boiler for controlling the digestive fermentation tank to the fermentation temperature by adjusting the temperature of the sewage to the fermentation temperature by heat-exchanging the refrigerant and sewage of the heat pump Since it does not operate, the methane gas energy used in the operation of the conventional boiler can be used for other purposes such as solid sewage sludge drying, which can lead to excellent effects in terms of resource recycling.

<Example 1>

As shown in Figure 2, the organic waste treatment apparatus for utilizing methane gas according to the present embodiment, anaerobic fermentation of the sewage treatment tank 10 and the sewage supplied from the sewage treatment tank 10 in which sewage is stored. The digestive fermentation tank 20 and the heat pump 30 for supplying the digestive fermentation tank 20 by heating the sewage supplied from the sewage treatment tank 10 to a temperature suitable for anaerobic fermentation. That is, the present embodiment is to heat the sewage rather than directly to the digestive fermentation tank 20, and thus, it is possible to utilize the methane gas energy generated in the digestive fermentation tank 20 to heat the digestive fermentation tank 20 for other purposes. It is.

The sewage treatment tank 10 and the digestive fermentation tank 20 have no novel configuration according to the present embodiment, and all that is used in the organic waste treatment technology for utilizing the existing methane gas can be used.

As is well known, the heat pump 30 includes a compressor 31 for compressing a refrigerant at high temperature and high pressure, a first heat exchanger (condenser) 32 for condensing the refrigerant compressed at high temperature and high pressure by the compressor 31, and An expansion valve 33 for depressurizing the refrigerant passing through the first heat exchanger 32 and a second heat exchanger (evaporator) 34 for evaporating the refrigerant depressurized by the expansion valve 33.

In this embodiment, the sewage is adjusted to an appropriate temperature according to the situation by using the refrigerant temperature of the heat pump 30.

In detail, the temperature of the sewage discharged from the sewage treatment tank 10 is about 10 ° C. unless a separate heating or cooling is performed. The temperature required for extinguishing and fermentation is 35 to 37 ° C., and the discharge temperature of the wastewater is It may be referred to as about 10 ℃.

Therefore, the sewage temperature is discharged from the sewage treatment tank 10 and the coolant passing through the first heat exchanger 32 of the heat pump 30 and the sewage supplied to the digestive fermentation tank 20 is heat exchanged to about 37 ° C. The oligohydride is discharged from the fermentation tank 20 to heat the refrigerant passing through the second heat exchanger 34 of the heat pump 30 to adjust to 10 ℃.

By such a configuration, wastewater can be discharged by anaerobic treatment of sewage, which is an organic waste. At this time, methane gas is generated and discharged from the digestive fermentation tank 20.

The present embodiment further includes a dryer 40 for drying the dry item using methane gas energy as a heat source.

The dryer 40 has a structure in which a dry matter is stored and supplies methane gas energy to the dry matter, which will be easily understood by those skilled in the art through a known methane gas energyization technique and a dryer technique. Is omitted.

The organic waste treatment method for utilizing methane gas according to this embodiment configured as described above is as follows.

(S10) sewage catchment.

The sewage generated in a factory or a livestock house is collected in the sewage treatment tank 10. Sewage treatment tank 10 is not a separate condition for anaerobic treatment, the temperature of the stored sewage will be about 10 ℃.

(S20) sewage supply.

The temperature of the sewage discharged from the sewage treatment tank 10 is 10 ℃ but the temperature suitable for anaerobic treatment is 35 ~ 37 ℃, the temperature of the sewage should be raised to the anaerobic treatment temperature, the first of the sewage and heat pump 30 The refrigerant passing through the heat exchanger 32 is allowed to heat exchange with each other. In this process, sewage takes heat away from the coolant and the temperature rises to about 37 ° C. On the contrary, the coolant lowers the temperature.

(S30) anaerobic reaction.

When a suitable amount of 37 ° C. sewage is put into the digestive anaerobic tank 20, the sewage is treated by the anaerobic reaction in the digestive anaerobic tank 20. Since the temperature of the sewage is a temperature suitable for the anaerobic reaction, the digestion anaerobic tank 20 is not heated, and since the anaerobic reaction of the sewage is well known, a detailed description thereof will be omitted.

(S40) wastewater discharge.

The wastewater from which the reaction is completed in the digestive anaerobic tank 20 is discharged. At this time, the temperature of the waste water is about 35 ° C, and if discharged in this state, the sewage system may be contaminated, so that the temperature is lowered by passing the second heat exchanger 34 of the heat pump 30 without being discharged as it is.

That is, when the wastewater discharged from the digestion anaerobic tank 20 and the refrigerant flowing inside the second heat exchanger 34 exchange heat, the wastewater loses heat to the refrigerant, thereby lowering the temperature of the wastewater.

(S50) Methane gas energy utilization.

(S30) During the anaerobic reaction, methane gas is naturally generated, and the methane gas is energized and then supplied to the dryer 40, and composted by drying the dried material contained in the dryer 40, for example, solid sewage sludge. .

<Example 2>

Since the heat exchange is performed only by the heat pump 30, the first embodiment has to increase the capacity of the heat pump 30, and the present embodiment is characterized in that it is configured to reduce the capacity of the heat pump 30. .

As shown in FIG. 3, the organic waste treatment apparatus for utilizing methane gas according to the present embodiment uses a temperature difference between wastewater discharged from the sewage treatment tank 10 and wastewater discharged from the digestive fermentation tank 20. The sewage and wastewater are exchanged with each other by the temperature difference and then adjusted to an appropriate temperature by the heat pump 30.

In this embodiment, a heat exchanger 50 for further exchanging sewage and wastewater is further applied.

That is, the heat exchanger 50 may be a plate heat exchanger having two flow paths, respectively, through which sewage discharged from the sewage treatment tank 10 and wastewater discharged from the digestive fermentation tank 20 flow.

Any one of the two flow paths of the heat exchanger 50 is connected to the outlet side of the sewage treatment tank 10 and the first heat exchanger 32 side of the heat pump 30, and the remaining flow path is a digestive fermentation tank 20. And the second heat exchanger 34 side of the heat pump 30.

According to this embodiment, the sewage discharged from the sewage treatment tank 10 first passes through the heat exchanger 50, and at this time, it is discharged from the digestive fermentation tank 20 to exchange heat with wastewater introduced into the heat exchanger 50. Therefore, the temperature of the sewage at 10 ° C heats up to about 20 ° C by heat exchange with the waste water at 35 ° C, on the contrary, the temperature of the 35 ° C wastewater drops to 25 ° C.

As a result, when the temperature of the sewage supplied to the digestive fermentation tank 20 (37 ° C.) and the temperature of the wastewater discharged from the digestive fermentation tank 20 (35 ° C.) are the same as those of Example 1, the first heat exchanger of the heat pump 30 Since the sewage heat exchanged with the 32 is 20 ° C., and the waste water heat exchanged with the second heat exchanger 34 is 25 ° C., the temperature difference is not larger than that of the first embodiment, so that the driving force of the heat pump 30 can be reduced and the heat pump The use quantity of 30 can be reduced.

1 is a block diagram of an organic waste treatment apparatus according to the prior art.

2 is a block diagram of an organic waste treatment apparatus for utilizing methane gas according to the first embodiment of the present invention.

3 is a block diagram of an organic waste treatment apparatus for utilizing methane gas according to a second embodiment of the present invention.

<Description of Signs for Main Parts of Drawings>

10: sewage treatment tank, 20: digestive fermentation tank

30: heat pump, 40: sewage sludge dryer

Claims (6)

A sewage treatment tank 10 in which sewage is stored; A digestive fermentation tank 20 for anaerobic treatment of sewage discharged from the sewage treatment tank; It includes a heat pump (30) to increase the temperature of the sewage discharged from the sewage treatment tank to put into the digestive fermentation tank, and to discharge the waste water by lowering the temperature of the wastewater passed through the digestive fermentation tank, The heat pump decompresses the refrigerant passing through the compressor (31), the first heat exchanger (32) for exchanging the refrigerant compressed at a high temperature and high pressure by the compressor with the sewage discharged from the sewage treatment tank, and the refrigerant passing through the first heat exchanger. An expansion waste (33), the organic waste treatment apparatus for utilizing the methane gas, characterized in that consisting of a second heat exchanger (34) for heat exchange between the refrigerant depressurized by the expansion valve and the waste water discharged from the digestive fermentation tank. The waste water discharged from the sewage treatment tank and the wastewater discharged from the digestive fermentation tank exchange heat with each other to heat the sewage and the wastewater, respectively. Organic waste treatment apparatus for utilizing methane gas, characterized in that further comprises a heat exchanger (50) for heat exchange with the first and second heat exchangers of the pump. The methane gas according to claim 1 or 2, further comprising a dryer (40) containing the dry matter inside and receiving the methane gas energy generated from the digestive fermentation tank as a heat source to dry the dry matter. Organic Waste Disposal Device for Use. A first step of raising the temperature of the sewage by exchanging heat between the sewage and the refrigerant passing through the first heat exchanger of the heat pump; A second step of putting anaerobic fermentation into the digestive fermentation tank by introducing the sewage whose temperature is increased by the first step; And a third step of lowering the temperature of the waste water by exchanging heat with the refrigerant passing through the second heat exchanger of the waste water and the heat pump after the second step. The first and second heat exchange of the heat pump after exchanging the sewage and wastewater with each other before passing the first and second heat exchangers of the heat pump. Organic waste treatment method for utilizing methane gas, characterized in that the supply to the air. The organic waste treatment according to claim 4, further comprising the step of energizing the naturally occurring methane gas in the second step and drying the dried material using the energy as a heat source. Way.

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