KR102222858B1 - Thermal hydrolysis reaction anaerobic digestion system of organic waste - Google Patents

Abstract

The present invention relates to a thermal hydrolysis anaerobic digestion system of organic waste capable of increasing the amount of biogas generated by thermally hydrolyzing organic waste using high temperature and high pressure steam and introducing a two-stage cooling device. To this end, the present invention provides a pretreatment unit for pretreating according to the characteristics of organic waste; A thermal hydrolysis unit preheating the preheated organic waste, supplying steam to the preheated organic waste to thermally hydrolyze, and secondary cooling the thermally hydrolyzed organic waste; A boiler unit comprising a waste heat boiler that generates the steam through waste heat and an auxiliary boiler that generates the steam through digestion gas and LNG (Liquefied Natural Gas); And an anaerobic digester for separating organic matter from the secondary cooled organic waste through methanogenic bacteria.

Description

Thermohydrolysis anaerobic digestion system of organic waste {THERMAL HYDROLYSIS REACTION ANAEROBIC DIGESTION SYSTEM OF ORGANIC WASTE}

The present invention relates to a technology for the anaerobic digestion of thermal hydrolysis of organic waste, and more specifically, an organic waste capable of increasing the amount of biogas generated by thermally hydrolyzing organic waste using high-temperature and high-pressure steam and introducing a two-stage cooling device. It relates to an anaerobic digestion system for thermal hydrolysis of waste.

The generation of organic wastes including sewage sludge, manure, food waste, and livestock manure continues to increase in the future due to the improvement of living standards, the increase of the population, the development of new cities, and the increase of income.

In addition, responding to the new climate system (Post 2020, Paris Agreement), prohibiting direct landfilling and marine emission of organic waste, implementing the RFS (Renewable Fuel Standard; mandatory mixing of renewable fuels), and energy crisis. Interest in biogas production is increasing rapidly.

The Ministry of Environment is continuously promoting the energy self-reliance project of sewage treatment plants to reduce the dependence on fossil energy used in sewage treatment plants such as electricity and LNG (Liquefied Natural Gas) to less than 50% as of 2030. There is a lot of progress in the establishment of solubilization facilities.

In anaerobic digestion for organic wastes such as food waste, sewage sludge, and manure, it is difficult to maintain a stable decomposition rate during anaerobic digestion due to different substrate characteristics, so solubilization is mostly applied as pretreatment for anaerobic digestion.

However, most of the previously installed solubilization facilities use ultrasonic and cavitation technologies, and are not showing the effect of removing organic matter compared to before installation.

Some local governments are considering the expansion of facilities and interest in thermohydrolysis anaerobic digestion as a way to improve the energy independence rate to comply with the Ministry of Environment's energy independence policy for sewage treatment plants (50% energy independence rate for sewage treatment plants as of 2030). (Operating & Maintenance) There are problems such as lack of know-how, insufficient process composition, and technical instability.Confidence in the possibility of securing the economic feasibility of the facility by increasing the amount of digestion gas generated and sludge reduction rate after stopping the operation of the existing installed facility Due to the shortage and lack of certainty in the construction of facilities, the rate of expansion of facilities has been low so far.

In addition, in order to lower the temperature of the thermally hydrolyzed substrate among the pyrohydrolysis anaerobic digestion facilities that are already in operation, the digestive solution inside the digester is contacted with the hot substrate that has been thermally hydrolyzed. There is a phenomenon that the activity decreases.

Therefore, in order to solve the conventional problem, the present invention thermally hydrolyzes organic waste using high-temperature and high-pressure steam and introduces a two-stage cooling device to increase the amount of biogas. Its purpose is to provide a digestive system.

In addition, the present invention lowers the temperature to 40 degrees before introducing the thermally hydrolyzed substrate into the digester to form conditions optimized for medium temperature digestion, thereby increasing the amount of biogas generated by 10% or more compared to the existing thermal hydrolysis process. Another object is to provide an anaerobic digestion system for pyrolysis of waste.

In addition, the present invention produces and supplies steam using waste heat generated in the process of generating digestion gas, and operates an auxiliary boiler that can use digestion gas and LNG at the same time when the power plant is not operated to treat organic waste without stopping the facility. Another object is to provide an anaerobic digestion system for thermohydrolysis of organic waste.

The problem of the present invention is not limited to those mentioned above, and other problems that are not mentioned will be clearly understood by those skilled in the art from the following description.

According to an aspect of the present invention for achieving the objects and other features of the present invention, a pretreatment unit for pretreating according to the characteristics of organic waste; A thermal hydrolysis unit preheating the preheated organic waste, supplying steam to the preheated organic waste to thermally hydrolyze, and secondary cooling the thermally hydrolyzed organic waste; A boiler unit comprising a waste heat boiler that generates the steam through waste heat and an auxiliary boiler that generates the steam through digestion gas and LNG (Liquefied Natural Gas); And there is provided a thermohydrolysis anaerobic digestion system of organic waste comprising an anaerobic digester for separating organic matter from the secondary cooled organic waste through methanogenic bacteria.

In the present invention, the pretreatment unit removes foreign substances when the organic waste is food or drinking water and crushes it into particles of a certain size, and when the organic waste is sewage sludge, dewaters through a centrifugal dehydrator, and the organic waste is condensed. Alternatively, in the case of manure, it is preferable to remove foreign substances and dehydrate through a centrifugal dehydrator.

In the present invention, the interior is partitioned through the partition wall, and it is preferable to further include an intermediate storage unit for storing the organic waste that has undergone the pretreatment.

In the present invention, the thermohydrolysis unit recovers waste heat, preheats the pre-treated organic waste, and mixes and homogenizes the preheated organic waste through a monopump; A reaction tank receiving steam from the waste heat boiler or the auxiliary boiler and first destroying the cell walls of the homogenized organic waste; And a storage tank for secondarily destroying the cell wall of the organic waste in which the cell wall is first destroyed in the reaction tank.

In the present invention, the thermal hydrolysis unit supplies cooling water to the thermally hydrolyzed organic waste to first cool the organic waste; And a secondary cooling device for secondary cooling the organic waste by supplying cooling water to the first cooled organic waste through a double tube heat exchanger method.

In the present invention, the secondary cooling device is preferably characterized in that the secondary cooling of the organic waste to lower the temperature of the first cooled organic waste between 35 ~ 41.5 ℃.

In the present invention, it is preferable to further include a extinguishing gas power generation unit for storing the extinguishing gas generated in the process of separating the organic matter from the organic waste, and generating electricity through the extinguishing gas.

In the present invention, it is preferable that the waste heat boiler recovers waste heat generated in the process of generating the electricity, and the auxiliary boiler is operated when the waste heat boiler cannot be used.

The thermohydrolysis anaerobic digestion system of organic waste according to the present invention provides the following effects.

The present invention has an effect of thermally hydrolyzing organic waste using high-temperature and high-pressure steam and introducing a two-stage cooling device to increase the amount of biogas generated.

The present invention has the effect of increasing the amount of biogas generated by 10% or more compared to the existing thermohydrolysis process by lowering the temperature to 40 degrees before introducing the thermally hydrolyzed substrate into the digester to form conditions optimized for medium temperature digestion. .

The present invention produces and supplies steam using waste heat generated in the process of generating digestion gas, and operates an auxiliary boiler that can use digestion gas and LNG at the same time when the power generation facility is not operated to treat organic waste without stopping the facility. It works.

The effects of the present invention are not limited to those mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the following description.

Figure 1 is a block diagram showing the anaerobic digestion system of organic waste according to the present invention.
FIG. 2 is a graph illustrating increasing the growth rate of methanogenic bacteria by lowering the organic waste to a temperature optimized for medium temperature digestion using a two-stage cooling technology of the anaerobic digestion system for thermal hydrolysis of organic waste according to the present invention. .
FIG. 3 is a graph of experimental data comparing the amount of biogas generated in the thermohydrolysis anaerobic digestion system of organic waste according to the present invention and the biogas generated in the existing process.

Additional objects, features and advantages of the present invention may be more clearly understood from the following detailed description and accompanying drawings.

Prior to the detailed description of the present invention, the present invention is capable of various modifications and various embodiments, and the examples described below and shown in the drawings are intended to limit the present invention to specific embodiments. It should be understood as including all changes, equivalents, and substitutes included in the spirit and scope of the present invention.

When a component is referred to as being "connected" or "connected" to another component, it is understood that it may be directly connected or connected to the other component, but other components may exist in the middle. It should be. On the other hand, when a component is referred to as being "directly connected" or "directly connected" to another component, it should be understood that there is no other component in the middle.

The terms used in the present specification are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In the present specification, terms such as "comprise" or "have" are intended to designate the presence of features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, but one or more other features. It is to be understood that the presence or addition of elements or numbers, steps, actions, components, parts, or combinations thereof does not preclude in advance.

In addition, terms such as "... unit", "... unit", "... module" described in the specification mean a unit that processes at least one function or operation, which is hardware, software, or hardware and It can be implemented as a combination of software.

In addition, in the description with reference to the accompanying drawings, the same components are assigned the same reference numerals regardless of the reference numerals, and redundant descriptions thereof will be omitted. In describing the present invention, when it is determined that a detailed description of a related known technology may unnecessarily obscure the subject matter of the present invention, a detailed description thereof will be omitted.

Hereinafter, a thermohydrolysis anaerobic digestion system for organic waste according to a preferred embodiment of the present invention will be described in detail with reference to FIGS. 1 and 2.

Figure 1 is a block diagram showing the anaerobic digestion system of organic waste according to the present invention.

As shown in Figure 1, the thermohydrolysis anaerobic digestion system 100 of organic waste according to the present invention is a pre-treatment unit 110 for pre-treatment according to the characteristics of organic waste, preheating the pre-treated organic waste, and preheated organic waste. A thermal hydrolysis unit 130 that supplies steam to the waste to thermally hydrolyze it and cools the thermally hydrolyzed organic waste secondary, a waste heat boiler 161 that generates steam through waste heat, and digestion gas and LNG (Liquefied Natural Gas). ), and an anaerobic digester 140 for separating organic matter from organic wastes secondarily cooled through methanogenic bacteria and a boiler unit 160 comprising an auxiliary boiler 162 for generating steam.

In addition, the thermohydrolysis anaerobic digestion system 100 of organic waste according to the present invention is partitioned inside through a partition wall, the intermediate storage unit 120 storing the organic waste that has undergone pretreatment, and the process of separating organic matter from the organic waste It stores the extinguishing gas generated in the, and further includes a extinguishing gas power generation unit 150 for generating electricity through the extinguishing gas.

The pretreatment unit 110 may pre-treat the organic waste carried into the anaerobic digestion system 100 for thermal hydrolysis of organic waste to meet the optimum solubilization conditions for thermal hydrolysis.

When the organic waste is food, the pretreatment unit 110 selects foreign materials with a foreign material selection rate of 97% or more through a crushing separator, a pulper, a drum screen, a cyclone, etc., and pre-treats the particle size to 3 mm or less. If the waste is negative water, it can be pretreated by sorting foreign substances through a drum screen or cyclone.

When the organic waste is sewage sludge, the pretreatment unit 110 dehydrates and pre-treats at a moisture content of around 80% through a centrifugal dehydrator. When the organic waste is livestock or manure, the pretreatment unit 110 selects foreign substances in the coarse crop treatment unit and uses a centrifugal dehydrator to achieve a moisture content of around 80%. It can be pretreated by dehydration.

The intermediate storage unit 120 may temporarily store the organic waste pretreated by the pretreatment unit 110 (eg, about 3 days). The intermediate storage unit 120 may store food and drinking water among organic wastes together, and may store sewage sludge, livestock manure, and manure together.

The intermediate storage unit 120 may always store organic waste even if the interior is separated through a partition wall and a failure or internal cleaning operation proceeds, and the organic waste may be transferred to the thermal hydrolysis unit 130.

The thermal hydrolysis unit 130 may receive the organic waste stored in the intermediate storage unit 120 and perform thermal hydrolysis. To this end, the thermal hydrolysis unit 130 may include a production tank 131, a reaction tank 132, a storage tank 133, a primary cooling device 134, and a secondary cooling device 135.

The production tank 131 may recover waste heat generated during treatment of organic waste from the reaction tank 132 and the storage tank 133 to preheat the organic waste pre-treated by the pretreatment unit 110. For example, the manufacturing tank 131 may preheat organic waste at 15 to 25°C to 95 to 100°C through waste heat.

In addition, the production tank 131 may be homogenized by mixing the organic waste up and down in a manner in which the organic waste is preheated and is circulated from the bottom through a monopump and circulated to the top. Here, the monopump is a uniaxial eccentric screw helical pump and corresponds to a rotary displacement metering pump, and a detailed description thereof will be omitted since it corresponds to a general pump that is widely used in the industrial field.

The reaction tank 132 may receive high-temperature and high-pressure steam produced from the waste heat boiler 161 or the auxiliary boiler 162 to first destroy the cell wall of the organic waste homogenized in the production tank 131. Steam may be generated in the waste heat boiler 161 or the auxiliary boiler 162 under high temperature and high pressure conditions of 200°C and 10 bar.

When the extinguishing gas power generation unit 150 and the waste heat boiler 161 operate normally, the reaction tank 132 receives steam generated by the waste heat boiler 161 as a heat source using waste heat generated from the extinguishing gas power generation unit 150. , When the digestion gas power generation unit 150 or the waste heat boiler 161 is malfunctioning or unable to operate normally due to periodic inspection, the steam generated from the auxiliary boiler 162 may be supplied.

The storage tank 133 may pressurize the organic waste in which the cell wall is first destroyed in the reaction tank 132 to secondarily destroy the cell wall of the organic waste in which the cell wall is first destroyed. That is, the storage tank 133 is formed to have a pressure of 0.5 bar or less so that the pressure is automatically lowered when the organic waste whose cell wall is first destroyed in the reaction tank 132 having a pressure of 6 bar is moved. The cell wall of organic waste can be destroyed secondarily without the device.

The primary cooling device 134 supplies cooling water corresponding to the effluent of the sewage treatment plant to the organic waste (that is, the organic waste that has been thermally hydrolyzed) having a cell wall of about 110° C. in the storage tank 133. It can be cooled first to have a temperature of ~ 85℃.

The secondary cooling device 135 supplies cooling water through a double-tube heat exchanger method, and generates organic wastes having a temperature of about 80 to 85°C, which is first cooled by the first cooling device 134, and has a temperature of about 40°C. It can be cooled secondarily so that it is possible.

The reason why the temperature of the organic waste is cooled to approximately 40° C. through the secondary cooling device 135 in the anaerobic digestion system 100 for thermal hydrolysis of organic waste according to the present invention will be described with reference to FIG. 2.

FIG. 2 is a graph illustrating increasing the growth rate of methanogenic bacteria by lowering the organic waste to a temperature optimized for medium temperature digestion using a two-stage cooling technology of the anaerobic digestion system for thermal hydrolysis of organic waste according to the present invention. .

As shown in FIG. 2, mesophilics are bacteria used to decompose organic matter from organic waste, and grow most at 35 to 41.5°C, and at 40°C or higher, the growth rate decreases rapidly. That is, the methanogenic bacteria rapidly decrease in activity at 40°C or higher, thereby reducing the rate of decomposing organic matter from organic waste and reducing the amount of biogas.

Accordingly, the present invention can increase the decomposition rate of organic matter using methanogenic bacteria by cooling the organic waste to 35 ~ 41.5 °C before introducing the organic waste into the anaerobic digester 140.

The anaerobic digester 140 may decompose organic matter from organic waste cooled to between 35 and 41.5° C. in the secondary cooling device 135 using methanogenic bacteria. The anaerobic digester 140 can efficiently decompose organic matter from organic waste by providing an optimal habitat environment for methanogenic bacteria by maintaining the internal temperature at approximately 40°C.

The anaerobic digester 140 may maintain the organic matter loading ratio of more than 2.0kg VS/m3*d and less than 2.5kg VS/m3*d to optimally maintain the activity of methanogenic bacteria. When the organic matter load rate is a high load state of 2.5kg VS/m3*d or more or a low load state of 2.0kg VS/m3*d or less, the activity of methanogenic bacteria in the anaerobic digester 140 decreases, and the organic matter decomposition rate may be reduced.

The extinguishing gas power generation unit 150 may store extinguishing gas generated in the process of separating organic substances from organic waste. At this time, the extinguishing gas power generation unit 150 may store the extinguishing gas after removing impurities such as moisture, hydrogen sulfide, and siloxane from the extinguishing gas. Here, the extinguishing gas corresponds to a gas containing more than 60% of methane.

The extinguishing gas power generation unit 150 may generate electricity from the extinguishing gas using a gas engine or a gas turbine generator. The extinguishing gas power generation unit 150 may transfer waste heat generated in the process of generating electricity to the waste heat boiler 161.

The boiler unit 160 may provide steam required when the thermal hydrolysis unit 130 thermally hydrolyzes organic waste, and may include a waste heat boiler 161 and an auxiliary boiler 162 for this purpose.

The waste heat boiler 161 may generate steam by recovering waste heat generated from the digestion gas power generation unit 150. The waste heat boiler 161 may generate steam by receiving waste heat from the extinguishing gas power generation unit 150 if normal operation is possible.

The auxiliary boiler 162 is, when the extinguishing gas power generation unit 150 or the waste heat boiler 161 is malfunctioning or unable to operate normally due to periodic inspection, the extinguishing gas stored in the extinguishing gas power generation unit 150 and LNG supplied from the outside. Steam can be generated by using.

On the other hand, the thermohydrolysis anaerobic digestion system 100 of organic waste according to the present invention has a characteristic capable of increasing the amount of biogas generated by 10% or more compared to the existing process, and this is proved through the experimental data below.

Experiment 1 corresponds to a technology that improves the thermohydrolysis anaerobic digestion process using a two-stage cooling technology according to the present invention, and Experiment 2 corresponds to a technology of performing a thermal hydrolysis anaerobic digestion process through a digester circulation line.

[Table 1] shows the experimental conditions of Experiment 1 and Experiment 2, and [Table 2] shows a table comparing the amount of biogas generated by operating the lab reactors of Experiment 1 and Experiment 2 continuously for 173 days under normal load conditions. .

division Experiment 1 (invention) Experiment 2 (existing technology) Experimental conditions After cooling the thermally hydrolyzed organic waste in two stages, it is operated by putting it into a digester (anaerobic digester 140) at 40°C. The thermally hydrolyzed organic waste is put into the digester at 35℃ through the three-stage cooling process (Dilution Water, Digester Recycle, Cooler). Organic matter loading factor 1.7~2.5gVS/L·d 1.7~2.5gVS/L·d Residence time 20 days 20 days

division Experiment 1
Gas generation amount (L/d) Experiment 2
Gas generation amount (L/d) division Experiment 1
Gas generation amount (L/d) Experiment 2
Gas generation amount (L/d) 1 day 3,616.3 3,746.9 43 days 4,745.0 4,072.9 2 days 5,148.1 4,275.2 44 days 4,179.5 3,655.6 3 days 4,764.5 4,396.2 45 days 4,176.3 3,693.6 4 days 4,733.2 4,377.2 46 days 4,829.5 4,476.0 5 days 4,622.3 4,400.8 47 days 4,845.8 4,374.6 6 days 4,855.5 4,185.0 48 days 4,891.3 4,317.6 7 days 4,972.5 4,742.3 49 days 4,673.5 4,293.3 8 days 4,953.0 4,348.4 50 days 4,909.7 4,352.1 9 days 4,585.3 4,540.3 51 days 4,674.5 4,234.3 10 days 5,070.0 4,344.4 52 days 4,656.5 4,328.2 11th 4,907.5 4,872.3 53 days 5,434.0 4,473.8 12 days 4,777.5 4,447.5 54 days 5,148.0 4,717.0 13th 5,177.3 4,704.3 55 days 4,862.0 4,593.3 14 days 5,086.3 4,957.9 56 days 5,291.0 4,840.6 15th 4,780.8 4,789.9 57 days 5,349.5 4,704.3 16th 4,706.0 4,957.9 58 days 5,772.0 4,697.9 17th 4,095.0 4,789.9 59 days 5,190.3 4,672.6 18th 4,950.3 4,976.9 60 days 5,551.0 4,789.3 19th 4,960.0 4,456.2 61 days 4,589.0 4,470.6 20 days 5,050.5 4,615.5 62 days 4,914.0 4,866.0 21st 4,918.3 4,775.2 63 days 5,453.5 4,730.8 22nd 5,534.8 4,907.2 64 days 5,183.8 5,027.7 23 days 4,972.5 4,380.5 65 days 5,365.8 4,568.0 24th 5,161.0 4,402.7 66 days 5,092.8 4,653.6 25 days 5,079.8 4,199.8 67 days 5,018.0 5,119.6 26th 5,414.5 4,964.3 68 days 5,187.0 5,585.5 27 days 4,813.3 4,253.0 69 days 5,492.5 6,051.5 28 days 5,333.3 4,834.5 70 days 5,200.0 4,694.8 29th 5,310.5 4,329.3 71 days 5,391.8 4,850.1 30 days 4,907.5 4,244.2 72 days 5,164.3 4,507.7 31 days 4,755.0 4,578.3 73 days 4,644.3 4,165.4 32 days 4,384.3 4,159.9 74 days 5,304.0 4,932.5 33 days 3,942.2 3,662.2 75 days 4,702.2 4,209.8 34 days 4,475.3 3,905.5 76 days 4,559.8 4,029.1 35 days 4,020.3 3,835.0 77 days 4,364.8 3,918.1 36 days 4,338.8 4,128.5 78 days 4,163.3 4,339.7 37 days 4,121.0 3,831.6 79 days 3,812.0 3,740.6 38 days 3,675.8 3,679.5 80 days 4,670.2 3,763.8 39 days 3,653.0 3,408.0 81 days 4,316.0 3,702.6 40 days 4,433.0 3,841.0 82 days 4,621.5 4,073.1 41 days 3,710.8 3,559.9 83 days 4,465.5 3,658.2 42 days 4,904.3 4,080.4 84 days 4,791.8 3,636.0 85 days 4,767.8 4,368.3 130 days 5,321.5 4,170.5 86 days 4,312.8 3,800.8 131 days 5,302.0 4,523.6 87 days 4,732.0 3,889.6 132 days 5,170.8 4,273.2 88 days 4,283.5 3,769.1 133 days 5,044.5 4,485.6 89 days 4,569.5 3,975.2 134 days 5,136.3 4,384.1 90 days 4,241.3 3,686.7 135 days 5,005.0 4,330.2 91 days 4,455.8 3,908.6 136 days 5,076.2 4,323.9 92 days 4,748.3 4,260.5 137 days 4,969.3 4,460.2 93 days 4,374.5 3,880.4 138 days 4,429.8 4,466.0 94 days 4,465.5 4,010.1 139 days 4,728.8 4,311.2 95 days 4,491.5 3,880.1 140 days 4,455.8 4,010.1 96 days 4,491.5 4,105.2 141 days 4,621.1 4,100.7 97 days 4,771.0 3,854.5 142 days 4,625.3 4,228.5 98 days 4,448.3 4,095.6 143 days 4,725.5 4,054.5 99 days 4,829.5 3,835.7 144 days 4,436.3 3,881.3 100 days 4,582.5 3,918.1 145 days 4,407.0 3,934.0 101 days 4,563.0 4,032.2 146 days 4,039.8 3,772.3 102 days 4,468.8 3,743.8 147 days 4,090.5 3,711.5 103 days 4,641.0 4,051.5 148 days 4,190.5 3,842.1 104 days 4,514.3 3,934.0 149 days 4,078.3 3,487.6 105 days 4,221.8 3,922.7 150 days 4,420.0 3,937.1 106 days 4,566.3 3,908.6 151 days 4,100.7 3,855.2 107 days 4,381.0 3,605.4 152 days 4,228.5 3,943.5 108 days 4,618.3 4,051.3 153 days 4,836.0 4,197.1 109 days 4,316.0 3,629.7 154 days 4,202.3 4,006.9 110 days 4,592.3 3,918.1 155 days 5,001.8 4,107.5 111 days 4,390.8 3,629.7 156 days 4,530.5 3,927.6 112 days 4,472.6 3,623.3 157 days 4,858.8 4,621.1 113 days 4,306.3 3,658.2 158 days 4,772.3 4,273.2 114 days 4,591.3 3,986.1 159 days 4,927.0 4,374.6 115 days 4,669.3 3,998.8 160 days 4,355.5 3,857.1 116 days 4,303.3 3,603.1 161 days 4,806.8 4,140.0 117 days 4,715.7 3,785.0 162 days 5,031.0 4,075.2 118 days 4,429.8 3,991.0 163 days 5,284.5 4,563.1 119 days 4,579.3 3,972.0 164 days 5,456.8 4,745.5 120 days 4,583.5 3,854.7 165 days 5,200.5 4,300.8 121 days 4,599.0 3,715.2 166 days 5,168.0 4,540.3 122 days 4,692.8 3,784.7 167 days 5,135.5 4,452.6 123 days 4,985.5 3,984.7 168 days 5,034.2 4,652.2 124 days 5,076.5 4,048.0 169 days 5,170.2 4,666.5 125 days 4,689.8 4,086.1 170 days 5,355.5 4,233.2 126 days 4,713.8 4,186.7 171 days 5,105.5 4,723.2 127 days 4,979.0 4,421.9 172 days 4,953.8 4,333.9 128 days 4,611.8 4,197.1 173 days 4,940.5 4,488.2 129 days 4,482.8 3,755.3 Average 4,736.2 4,228.6

3 is a graph comparing the amount of biogas generated in Experiment 1 and 2, and according to the experimental results, it can be seen that the average amount of biogas generated in Experiment 1 was 10.1% higher than that in Experiment 2. FIG.

Existing thermohydrolysis anaerobic digestion process firstly supplies dilution water to organic wastes that have been pyrolyzed and cools them to 90°C. After contacting the first cooled organic waste, it is secondarily cooled to 50°C. In this process, the mesophilic microorganisms (35 ~ 40 °C optimal condition) constantly contact the organic waste at a high temperature of 90 °C, resulting in a problem that the number of mesophilic microorganisms decreases and the activity decreases.

The organic waste that has completed secondary cooling flows into a cooler, is cooled from 50°C to around 35°C by the cooler, and flows into the digester.

The embodiments described in the present specification and the accompanying drawings are merely illustrative of some of the technical ideas included in the present invention. Accordingly, it is obvious that the embodiments disclosed in the present specification are not intended to limit the technical idea of the present disclosure, but to explain the technical idea, and thus the scope of the technical idea of the present disclosure is not limited by these embodiments. Modification examples and specific embodiments that can be easily inferred by those skilled in the art within the scope of the technical idea included in the specification and drawings of the present invention should be interpreted as being included in the scope of the present invention.

100: Thermohydrolysis anaerobic digestion system of organic waste
110: pretreatment unit
120: intermediate storage
130: thermal hydrolysis unit
140: anaerobic digester
150: digestive gas power generation unit
160: boiler part

Claims (8)

A pretreatment unit for pretreating according to the characteristics of organic waste;
An intermediate storage unit partitioned through the partition wall and storing the organic waste that has undergone the pretreatment;
A thermal hydrolysis unit preheating the preheated organic waste, supplying steam to the preheated organic waste to thermally hydrolyze, and secondary cooling the thermally hydrolyzed organic waste;
A boiler unit comprising a waste heat boiler that generates the steam through waste heat and an auxiliary boiler that generates the steam through digestion gas and LNG (Liquefied Natural Gas);
An anaerobic digester for separating organic matter from the secondary cooled organic waste through methanogenic bacteria; And
Including; a digestion gas power generation unit for storing the digestion gas generated in the process of separating the organic matter from the organic waste, and generating electricity through the digestion gas,
The pretreatment unit,
When the organic waste is food, the foreign matter is sorted with a foreign matter sorting rate of 97% or more through a crushing sorter, a pulper, a drum screen, and a cyclone, and the particle size is pretreated to be 3 mm or less,
When the organic waste is negative waste water, foreign substances are sorted and pretreated through a drum screen and a cyclone,
When the organic waste is sewage sludge, pretreatment is performed by dewatering with a moisture content of 80% through a centrifugal dehydrator,
In the case where the organic waste is livestock or manure, foreign substances are selected in a co-crop treatment machine and pretreated by dehydrating at a moisture content of 80% through a centrifugal dehydrator,
The intermediate storage unit temporarily stores the organic waste pretreated by the pretreatment unit, stores food and drinking water among the organic wastes together, and stores sewage sludge, livestock manure, and manure among the organic wastes,
The extinguishing gas power generation unit stores extinguishing gas containing 60% or more of methane after removing impurities of moisture, hydrogen sulfide, and siloxane from the extinguishing gas,
The waste heat boiler is operated by receiving waste heat generated in the process of generating electricity from the extinguishing gas power generation unit, and the auxiliary boiler includes extinguishing gas stored in the extinguishing gas power generation unit and external It is operated using LNG supplied from
The thermal hydrolysis unit,
A production tank for recovering waste heat, preheating the pre-treated organic waste, and homogenizing the preheated organic waste by mixing up and down through a monopump;
A reaction tank receiving steam from the waste heat boiler or the auxiliary boiler and first destroying the cell wall of the homogenized organic waste;
A storage tank for secondarily destroying the cell wall of the organic waste in which the cell wall is first destroyed in the reaction tank;
A primary cooling device for primary cooling the organic waste by supplying cooling water to the thermally hydrolyzed organic waste; And
Including; a secondary cooling device for secondary cooling the organic waste by supplying cooling water to the first cooled organic waste through a double tube heat exchanger method,
The primary cooling device supplies cooling water corresponding to the discharged water from the sewage treatment plant to the organic waste having a secondary destruction of the cell wall in the storage tank at 110° C., and performs primary cooling to have a temperature of 80 to 85° C.,
The secondary cooling device supplies cooling water through a double tube heat exchanger method to secondaryly cool the organic waste first cooled in the primary cooling device to a temperature of 40°C. Hydrolytic anaerobic digestion system. delete delete delete delete delete delete delete

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