KR102625530B1 - Hybrid Biogas Production System - Google Patents

Abstract

The present invention relates to a hybrid biogas production system, which has an ammonia gas production tank at the top and a carbon dioxide absorption tank directly below, so that biogas and wastewater discharged from the anaerobic treatment of livestock manure are converted into ammonia in a small space in a single housing. It can remove and absorb carbon dioxide, and can degas the ammonia by gravity-falling it from the ammonia gas production tank. The first effluent water from which ammonia has been removed from the ammonia gas production tank at the top is supplied to the carbon dioxide absorption tank without a separate driving device to produce ammonia. It relates to a hybrid biogas production system that can save energy when changing degassed and strong base first effluent into neutralized second effluent.
This invention was researched with support from the Green Forest Food Technology Planning and Evaluation Institute's "Development of biogas-ammonia power generation technology at farm village level using Korean beef and dairy cow manure for farm income generation" project funded by the Ministry of Agriculture, Food and Rural Affairs (project specific) Number: 1545028287, Detailed project number: 00233134).

Description

Hybrid biogas production system {Hybrid Biogas Production System}

The present invention relates to a hybrid biogas production system, and more specifically, by placing an ammonia gas production tank at the top and providing a carbon dioxide absorption tank directly below, the biogas and wastewater discharged from the anaerobic treatment of livestock manure are combined into one housing. It is about a hybrid biogas production system that can remove ammonia and absorb carbon dioxide in a small space. This invention was researched with support from the Green Forest Food Technology Planning and Evaluation Institute's "Development of biogas-ammonia power generation technology at farm village level using Korean beef and dairy cow manure for farm income generation" project funded by the Ministry of Agriculture, Food and Rural Affairs (project specific) Number: 1545028287, Detailed project number: 00233134).

The treatment of food waste or livestock waste from livestock farms can be divided into incineration, landfill, and recycling technologies, and recycling technologies are divided into feed and composting.

In the case of incineration in the treatment of such organic waste, it is a technology that has been specified due to the serious problem of polluting the environment by causing secondary pollution due to the generation of dioxins due to low calorific value and incomplete combustion due to moisture content, and feed technology is from the perspective of recycling of resources. Although it is the most widely used technology, it requires very complicated procedures in the processing process and is subject to many problems.

In addition, composting technology includes aerobic treatment methods and anaerobic treatment methods, but the aerobic treatment method requires the use of moisture regulators (sawdust, etc.) to facilitate the respiration of aerobic microorganisms, which has the disadvantage of being less economical and causing air pollution problems. On the other hand, the anaerobic treatment method has the advantage of not only solving the odor problem by blocking the process from the atmosphere, but also generating usable biogas (approximately 70% methane) during the anaerobic treatment process, which can be used to generate biogas power.

In this way, the method of using organic waste as an energy resource is attracting attention and is continuously being developed from the perspective of environmental conservation and new renewable energy source. Biogas is produced by anaerobic digestion of organic waste and can be used as electricity and heat energy. Since it can be converted and used as a by-product and used as fertilizer, etc., its usability is high and continuous development is required.

In this way, in anaerobic digesters and landfills that process high-concentration organic waste such as livestock manure and food waste, biogas is generated as organic materials decompose in anaerobic conditions. The main components of this biogas are methane (50-70%) and carbon dioxide (30%). ~50%), and contains trace amounts of impurities such as hydrogen sulfide, ammonia, hydrogen, nitrogen, volatile organic compounds, and siloxane. Organic waste, which is the raw material, is constantly generated through human activities and various industrial activities, so the amount generated is It is continuously increasing.

Biogas is a combustible material and can be used as an energy source because its main ingredient is methane. However, the methane content is almost half that of natural gas and it contains a lot of impurities, so it is mainly used as a fuel for processes that produce electricity or heat, such as boilers and combined heat and power generation. It is used only for limited purposes.

However, recently, mainly in Europe, there has been a growing trend to increase the proportion of methane and use biomethane with impurities removed as fuel for higher quality rather than simple use of biogas.

Biomethane is a gas with a methane concentration of 97% or more, oxygen and nitrogen concentrations of 3% or less, and hydrogen sulfide and siloxane within the limit. Its calorific value is about 85% of natural gas, but it is not used in homes, transportation, or power generation facilities. It can be used in all places where existing natural gas is used.

This purification of biogas is divided into a pretreatment process to remove hydrogen sulfide, siloxane, and other impurities contained in biogas, and a biomethane purification process to remove carbon dioxide and remaining impurities. The purification methods for biomethane are generally: Absorption method, adsorption method and membrane method are known.

Recently, a number of patents have been applied for in Korea, and research to purify biomethane is actively underway, but commercialization is still difficult and most of them are implemented by introducing technologies and systems from foreign countries.

In this way, there is an emerging need for biogasification technology that can extract methane gas from livestock waste and utilize it to produce electricity and heat, or secure additional sources of income such as income from electricity and heat sales, and other organic waste import fees.

The system that produces biogas by processing livestock waste requires ammonia degassing and carbon dioxide absorption, but the ammonia degassing tower or carbon dioxide absorption tower requires a large space, making it difficult for small-scale livestock farms to install.

In addition, ammonia removal and carbon dioxide absorption required continuous use of multiple pumps and compressors, which consumed a lot of energy and required space to install these driving devices.

KR 10-0743373 (registration number) 2007.07.23. KR 10-1234286 (registration number) 2013.02.12. KR 20-2015-0003169 (Publication number) 2015.08.21.

The present invention is intended to solve the above problems, by placing an ammonia gas production tank through ammonia or degassing at the top and providing a carbon dioxide absorption tank directly below to collect the gas and wastewater discharged from the anaerobic treatment of livestock manure in one housing. The goal is to provide a hybrid biogas generation system that can remove ammonia and absorb carbon dioxide in biogas in a small space.

In the present invention, ammonia can be degassed by falling in an ammonia gas production tank by gravity, and the first effluent water from which ammonia has been removed from the ammonia gas production tank at the top is supplied to the carbon dioxide absorption tank without a separate pump to degas the ammonia and remove the first strong base. The aim is to provide a hybrid biogas production system that can save energy when changing effluent into neutralized secondary effluent.

The present invention provides a series of small-sized treatment tanks side by side, supplies wastewater to each, and installs a paddle, which is a corrugated inclined plate, downward in the horizontal direction inside each treatment tank to form a plurality of paddles in which the inflow wastewater is formed in a zigzag pattern. By falling and moving by their own weight, the residence time is extended, providing a hybrid biogas production system that facilitates ammonia degassing.

The present invention is provided with a plurality of paddles having a concave-convex corrugated upper surface inclined downward in the longitudinal direction inside a rectangular-shaped small treatment tank, so that the inflowed wastewater moves alternately through drop movement and uneven movement, and in the plurality of small treatment tanks. The first effluent from which the ammonia gas group has been removed is stored in one effluent storage tank and dropped into a carbon dioxide absorption tank, thereby providing a hybrid biogas generation system that has high ammonia degassing efficiency and allows control of the supply amount to the carbon dioxide absorption tank.

In order to achieve the above object, the present invention has an ammonia gas production tank 200 placed at the top to receive wastewater from livestock manure treated in an anaerobic digestion tank, and absorbs carbon dioxide to receive biogas that is processed in the anaerobic digestion tank and discharged as gas. In the hybrid biogas production system in which the tank 100 is disposed at the bottom, the ammonia gas production tank 200 includes a plurality of rectangular cross-sectional treatment tanks 210 with open bottoms spaced apart from each other and arranged consecutively; At the lower part of the treatment tank 210, an effluent water storage tank 240 is provided, which has an upper-lower narrow shape with a closed lower end, and into which the first effluent water treated in the treatment tank 210 falls and is stored; A carbon dioxide absorption tank 100 having a rectangular cross-section perpendicular to the treatment tank 210 is provided below the effluent storage tank 240; An effluent pipe 250 is provided to vertically connect the lower part of the effluent storage tank 240 and the lower part of the carbon dioxide absorption tank 100 to supply the first effluent water to the carbon dioxide absorption tank 100; The first effluent and biogas flow into the lower part of the carbon dioxide absorption tank 100, and flow into opposite horizontal surfaces, respectively.

The plurality of treatment tanks 210 of the present invention have the same shape and size; Each treatment tank 210 is provided with a plurality of horizontal wastewater inlets 215 protruding into the treatment tank 210 on the upper side, and an ammonia gas outlet 216 through which ammonia gas is discharged at the top. do.

In addition, the inside of the treatment tank 210 of the present invention is provided with a plurality of paddles 220 having a rectangular shape; Each paddle 220 has a rectangular shape forming four sides of a small paddle surface 221 with a small length and a large paddle surface 222 with a long length; The paddle surface 221 has one side (221a) coupled to the inner wall of the treatment tank 210 and the other side (221b) spaced apart from the inner wall of the treatment tank 210, and the paddle surface 222 has both sides. It is coupled to the inner wall of the treatment tank 210; The paddle 220 has three sides closed by the inner wall of the treatment tank 210 and one side is open.

In addition, the paddle 220 of the present invention has irregularities formed on the upper surface, and the large paddle surface 222 is inclined downward from one surface 221a coupled to the inner wall surface of the small paddle surface of the small treatment tank 210; Each paddle 220 is spaced apart up and down, and one side 221a of the paddle surface 221 is formed in the opposite direction inside the treatment tank 210.

In addition, in the effluent storage tank 240 of the present invention, the first upper surface 241, which is in contact with the inside of the treatment tank 210, is open, and the second upper surface 242, which is not in contact with the treatment tank 210, is closed. and; A first outflow hole 251 connected to the outflow pipe 250 is formed on one side of the lower part.

In addition, the carbon dioxide absorption tank 100 of the present invention includes a main absorption tank 120 of a rectangular shape; The main absorption tank 120 has a first inlet hole 252 formed on one lower side to receive the first effluent water from the effluent storage tank 240, and the other side of the lower side into which biogas generated from anaerobic treatment of livestock waste flows into. A mountain stone 140 is placed; A gas collection tank 111 in the shape of a lower chamber is provided on the upper part of the main absorption tank 120 to collect biogas; The gas collection tank 110 is provided with a biogas outlet 111 through which biogas is discharged.

In addition, a closed blocking surface 243 is formed between the gas collection tank 110 and the effluent storage tank 240 of the present invention to prevent movement; The gas collection tank 110 and the effluent storage tank 240 have the same shape and are arranged in opposite directions around the blocking surface 243.

In addition, the diffuser stone 140 of the present invention includes a supply pipe 141 extending into the carbon dioxide absorption tank 100 and a plurality of through holes 142 disposed in the supply pipe 142.

Therefore, the hybrid biogas generation system of the present invention has an ammonia gas production tank through ammonia degassing at the top and a carbon dioxide absorption tank directly below, so that the gas and wastewater discharged from the anaerobic treatment of livestock manure can be stored in a single housing with a small space. It is effective in removing ammonia and absorbing carbon dioxide in biogas.

In the present invention, ammonia can be degassed by falling in an ammonia gas production tank by gravity, and the first effluent water from which ammonia has been removed from the ammonia gas production tank at the top is supplied to the carbon dioxide absorption tank without a separate pump to degas the ammonia and remove the first strong base. There is an advantage in energy savings when changing the effluent to neutralized secondary effluent.

The present invention provides a series of small-sized treatment tanks side by side, supplies wastewater to each, and installs a paddle, which is a corrugated inclined plate, downward in the horizontal direction inside each treatment tank to form a plurality of paddles in which the inflow wastewater is formed in a zigzag pattern. There is an advantage in that the residence time is prolonged as the particles fall and move under their own weight, allowing for smooth degassing of ammonia.

The present invention provides a plurality of paddles with a concavo-convex corrugated upper surface inclined downward in the longitudinal direction inside a rectangular-shaped digestion tank, so that the inflow wastewater alternates between drop movement and uneven movement, and ammonia is removed from the plurality of digestion tanks. Since the first effluent from which gases have been removed is stored in one effluent storage tank and dropped into the carbon dioxide absorption tank, ammonia degassing efficiency is high and the amount of supply to the carbon dioxide absorption tank can be controlled.

1 is an external perspective view of a hybrid biogas production system according to the present invention,
Figure 2 is a perspective view with the upper and lower covers removed in the hybrid biogas production system according to the present invention;
Figure 3 is a front view and a side view of the hybrid biogas production system according to the present invention;
Figure 4 is a cross-sectional exploded view of the ammonia gas production tank 200 of the hybrid biogas production system according to the present invention.
Figure 5 is a cross-sectional view of the treatment tank 210, which is a component of the ammonia gas production tank 200 of the hybrid biogas production system according to the present invention.
Figure 6 shows a paddle 220 inserted into the small treatment tank 210 of the hybrid biogas production system according to the present invention,
Figure 7 is an internal perspective view of the hybrid biogas production system according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings.

The present invention is a hybrid biogas production system (10) that sequentially performs ammonia gas production through ammonia degassing and carbon dioxide absorption in biogas in one system formed up and down, as shown in FIGS. 1 to 7,

At the top is an ammonia gas production tank 200 that receives wastewater discharged from livestock waste treatment in an anaerobic digestion tank (not shown), and a carbon dioxide absorption tank 100 that receives biogas processed in an anaerobic digestion tank and discharged as gas. In the hybrid biogas production system 10 disposed directly below,

The ammonia gas production tank 200 has an open bottom. A plurality of rectangular cross-sectional treatment tanks 210 are arranged continuously and spaced apart from each other,

At the lower part of the treatment tank 210, an effluent water storage tank 240 is provided, which has an upper-lower-hole shape with a closed bottom and where the first effluent water treated in the treatment tank 210 falls and is stored,

A carbon dioxide absorption tank 100 having a rectangular cross-section perpendicular to the treatment tank 210 is provided below the effluent storage tank 240,

An effluent pipe 250 is provided that vertically connects the lower part of the effluent storage tank 240 and the lower part of the carbon dioxide absorption tank 100,

The first effluent and biogas flow into the lower part of the carbon dioxide absorption tank 100, and flow into opposite horizontal surfaces of the carbon dioxide absorption tank 100, respectively.

The plurality of treatment tanks 210 are of the same size and shape, and each treatment tank 210 has a wastewater inlet 215 protruding into the treatment tank 210 on its upper side in a horizontal direction. It is provided with a plurality of and an ammonia gas outlet 216 through which ammonia gas is discharged is provided at the top.

Inside the treatment tank 210, a plurality of rectangular-shaped paddles 220 are provided below the wastewater inlet 215, and each paddle 220 has a small paddle surface 221 having a small length on four sides and a long It is made of a large paddle surface 222 having a length, and the small paddle surface 221 has one side (221a) coupled to the inner wall of the treatment tank 210 and the other side (221b) is connected to the inner wall of the treatment tank 210. is spaced apart from; Both sides of the planer surface 222 are coupled to the inner wall of the treatment tank 210.

The paddle 220 has irregularities 223 formed on its upper surface, a large paddle surface 222 is inclined downward from one surface 221a of the small paddle surface, and a plurality of paddles 220 are spaced apart up and down, and each paddle 220 ) One side (221a) of the small paddle surface 221 is formed in the opposite direction inside the small treatment tank 210.

The effluent storage tank 240 has a first upper surface 241 that is in contact with the inside of the treatment tank 210, is open, a second upper surface 242 that is not in contact with the inside is closed, and is connected to the effluent pipe 250 on one lower side. A first outflow hole 251 is formed.

Biogas is produced through anaerobic digestion of organic materials consisting of livestock manure, and its main components are methane and carbon dioxide, and contains trace amounts of impurities such as ammonia, hydrogen, nitrogen, volatile organic compounds, and siloxane, including hydrogen sulfide. In the present invention, biogas is First effluent is generated by degassing ammonia from wastewater into a gaseous state, carbon dioxide in the biogas is dissolved and absorbed in the strong base first effluent, and contact with the strong base first effluent water produces high purity biogas by removing hydrogen sulfide from the biogas. do.

In the present invention, wastewater may contain sludge in a state separated from biogas in an anaerobic digestion tank (not shown), and refers to the state before ammonia gas is removed in the ammonia gas production tank 200, and is a product from which ammonia gas has been removed. The state in which the first effluent falls due to its own weight and the carbon dioxide is absorbed in the carbon dioxide absorption tank 100 and the pH is neutralized is called the second effluent. However, in the process in which wastewater flows in and passes over the paddle 220 in the ammonia gas production tank 200 and separates ammonia gas, the first effluent water and ammonia are mixed, but this is referred to as 'wastewater'.

The ammonia gas production tank 200 causes the strongly base wastewater to fall onto the paddle 220, which is a corrugated sloping plate disposed in opposite directions up and down and inclined downward, generating turbulence and causing degassing of ammonia gas due to the drop, and absorbing the carbon dioxide. In the tank 100, carbon dioxide is absorbed and hydrogen sulfide is removed through contact between the biogas flowing in from the anaerobic digestion tank and the first effluent water flowing in from the ammonia gas production tank 200, and high-purity biogas with a relatively high methane ratio and carbon dioxide are produced. A second effluent that is absorbed and neutralized is generated.

The anaerobic digester processes livestock waste to emit biogas and carbon dioxide, and the configuration of generating wastewater containing ammonia is known, so detailed description thereof will be omitted.

In the present invention, the wastewater supplied to the ammonia gas production tank 200 is in a strongly basic state by injecting chemicals such as sodium hydroxide (NaOH), and preferably has a pH of 11 or higher.

As shown in FIGS. 1 and 2, the ammonia gas production tank 200 is disposed directly above the carbon dioxide absorption tank 100, and is provided with a plurality of rectangular-shaped reprocessing tanks 210 spaced apart from each other. Each treatment tank 210 has the same size and shape both inside and outside. In the present invention, the small treatment tank 210 is shown as three, so it is described as three, but is not limited to this.

Each treatment tank 210 has a rectangular cross-section, and the entire ammonia gas production tank 200, which consists of three treatment tanks 210, also has a rectangular cross-section. For convenience of explanation, in the present invention, in a rectangular shape, the long side is written as 'horizontal' and the short side is written as 'vertical'. The side of the horizontal side is written as the horizontal side, and the side of the vertical side is written as the vertical side. Therefore, the horizontal plane has a larger area than the vertical plane.

In the present invention, the ammonia gas production tank 200 includes three treatment tanks 210 and has a rectangular shape perpendicular to the treatment tanks 210. That is, the horizontal direction of the treatment tank 210 becomes the vertical direction in the ammonia gas production tank 200, and the vertical direction of the treatment tank 210 becomes the horizontal direction in the ammonia gas production tank 200. Accordingly, the treatment tanks 210 having a rectangular cross-section are continuously arranged in parallel, and each treatment tank 210 is spaced apart from each other. The three treatment tanks 210 are gathered together to form one large rectangular shape, and the rectangles of each treatment tank and all treatment tanks have horizontal directions perpendicular to each other.

Meanwhile, the present invention places the carbon dioxide absorption tank 100 directly below the ammonia gas production tank 200 to form a single housing to process wastewater and gas in a small space after anaerobic digestion of livestock manure, thereby absorbing carbon dioxide. The rectangular directions of the tank 100 and the ammonia gas production tank 200 are the same, and accordingly, the rectangular directions of the carbon dioxide absorption tank 100 and the treatment tank 210 are perpendicular. In the present invention, the carbon dioxide absorption tank 100 and the ammonia gas production tank 200 form an upper and lower end of a rectangle with the same cross-section where the horizontal and vertical sides have the same length, thereby forming an overall single housing. Therefore, the present invention can simultaneously produce ammonia gas through ammonia degassing and absorb carbon dioxide in biogas in one housing.

In the present invention, the ammonia gas production tank 200 is provided with a plurality of separate treatment tanks 210, so that the inflow amount and inflow rate of wastewater and the stability of the process can be secured. In the present invention, since the first effluent treated in the treatment tank 210 falls by gravity, it is difficult to control the flow rate or change the operating conditions in the carbon dioxide absorption tank 100, so the ammonia gas production tank 200 at the upper stage is difficult. It is desirable to selectively control the inflow rate of wastewater.

Additionally, providing a plurality of small-sized treatment tanks 210 can increase ammonia degassing efficiency. This will be explained later.

In the present invention, each treatment tank 210 is formed in the shape of a square pillar with a cross-section of a long horizontal side and a short vertical side, and is provided with a plurality of wastewater inlets 215 horizontally on the upper side, and degassed ammonia gas. An ammonia gas outlet 216 whose width narrows toward the top is formed to discharge the ammonia gas to the outside from the ammonia gas production tank 200, and the lower part is opened so that the first effluent water degassed with ammonia falls by its own weight into the effluent water storage tank ( 240).

The wastewater inlet 215 is installed to protrude into the treatment tank 210 as if a straw is inserted, so that the wastewater flowing into the inside falls with a drop instead of flowing along the inner wall of the treatment tank 210. The wastewater flowing in through the wastewater inlet 215 freely falls and falls on the upper surface of the paddle 220, and as it flows slowly along the paddle, ammonia gas is degassed to become first effluent water, which is stored in the effluent storage tank 240.

The ammonia gas outlet 216, which discharges ammonia gas that is separated from the wastewater and moves upward, is formed in the shape of a lower chamber so that ammonia gas can be collected and discharged.

In this way, the ammonia gas separated from the wastewater flowing into the treatment tank 210 is discharged through the ammonia gas outlet 216, and is collected in a separate ammonia gas storage tank (not shown) and converted to a hydrogen medium by electrolysis or heat. It can be used as an energy source for carbon-free ammonia power generation by burning it.

The treatment tank 210 is provided with a plurality of paddles 220, the upper surface of which is corrugated with irregularities 223, spaced apart vertically. Each paddle 220 is made of a small paddle surface 221 having a small length on four sides in a square shape and a large paddle surface 222 having a long length, and one side 221a of the small paddle surface 221 is used in the treatment tank. It is coupled to the inner wall of the treatment tank 210 and the other side 221b is spaced apart from the inner wall of the treatment tank 210, and both sides of the planer surface 222 are coupled to the inner wall of the treatment tank 210.

The paddle 220 has an upper surface wrinkled with irregularities 223, a large paddle surface 222 is inclined downward from the one surface 221a of the small paddle surface, and each paddle 220 is spaced up and down, with the upper and lower small paddle surfaces 221 ) is formed in the opposite direction inside the treatment tank 210.

That is, the square paddle 220 has two long sides (large paddle side 222) and one short side (small paddle side 221a) combined with the inner wall of the treatment tank 210 (three sides are closed). ), the wastewater travels down the corrugated upper surface through vibration, falls from the other surface 221b of the open paddle surface, lands on the upper surface of the paddle 220 below, and repeats the same movement.

In Figure 4, the paddle 220 is installed to be inclined downward at an inclination of 8 degrees, and the height of the protruding portion of the unevenness 223 formed on the upper surface is shown to be 5 mm and the spacing is 10 mm. Wastewater with a pH of 11 or higher flowing into the treatment tank 210 falls by gravity, and the lower paddle catches and moves the wastewater falling from the end of the upper paddle, generating turbulence and inducing ammonia gas degassing due to the drop. The paddles 220 are installed to be inclined downward in the horizontal longitudinal direction of the treatment tank 210 and are spaced at regular intervals but arranged in a zigzag pattern to lengthen the time for wastewater to fall, thereby allowing the ammonia gas to be smoothly separated and discharged.

In the present invention, a plurality of small treatment tanks 210 of the same shape are arranged in parallel, and the parallel arrangement of such small treatment tanks 210 can achieve higher degassing efficiency and appropriate flow rate control than a single large ammonia gas production tank. You can.

If only one large treatment tank is installed, the length of the inclined plate becomes longer, which reduces degassing efficiency. Since the degassing efficiency is ideal when there are many irregularities and turbulence is formed due to drops, it is desirable to go through several stages of an inclined plate of appropriate length. When one large treatment tank is installed, the length of the paddle becomes longer, so the number of paddles must be reduced, and the shock caused by the drop between paddles is reduced.

If too much wastewater is injected from the upper treatment tank, the flow rate increases and it cannot be sufficiently degassed and falls into the effluent storage tank, so the treatment capacity per treatment tank is limited. Therefore, having multiple small-sized small treatment tanks can treat more wastewater in the same time than one large treatment tank. In addition, the carbon dioxide absorption tank 100 at the bottom is provided with a sufficient flow rate of the first effluent water to form a certain depth or more for gas-liquid contact to occur, so it is equipped with a plurality of small treatment tanks smaller than one large ammonia gas production tank. This has high ammonia degassing efficiency and carbon dioxide absorption efficiency. In addition, the amount of treatment can be adjusted by operating the small treatment tank separately into 1st, 2nd, and 3rd units depending on the amount of wastewater injected.

The effluent storage tank 240 disposed at the lower part of the treatment tank 210 has a first upper surface 241 that is in contact with the inside of the treatment tank 210 open, a second upper surface 242 that is not in contact with the inside of the treatment tank 210, and is closed. A first outflow hole 251 coupled to the effluent pipe 250 is formed on one side, and the first effluent water separated from the treatment tank 210 falls and is stored.

The effluent storage tank 240 is a place where the first effluent water from the three treatment tanks 210 is collected. It is shaped like a hopper with a wide upper part and a narrow lower part, so that it facilitates the collection of the first effluent water and releases a small amount of water. Even the primary runoff has depth and height. Since the first effluent water supplied to the carbon dioxide absorption tank 100 through the effluent pipe 250 is supplied by its own weight, the depth of the first effluent water in the effluent storage tank 240 is important. The higher the height of the first effluent water stored in the effluent storage tank 240, the greater the amount of first effluent water flowing out of the effluent water pipe 250, thereby increasing the carbon dioxide absorption rate in the carbon dioxide absorption tank 100 at the lower stage. A valve (not shown) is provided in the effluent pipe 250 to move the first effluent water to the carbon dioxide absorption tank 100 when the first effluent water is stored in the effluent storage tank 240 to a certain extent.

In the present invention, since the first effluent water is directly supplied to the carbon dioxide absorption tank 100 through the effluent pipe 250, the flow rate control is determined by the amount of wastewater flowing into the ammonia gas production tank 200. The bottom of the effluent storage tank 240 is blocked, so the first effluent can only move to the effluent pipe 250.

The carbon dioxide absorption tank 100 includes a main absorption tank 120 with a rectangular cross-section. The main absorption tank 120 has a first inlet hole 252 formed on one lower side to receive the first effluent water from the effluent storage tank 240, and an acid stone 140 through which biogas generated through anaerobic treatment flows into the lower side. ) is placed. The upper part of the main absorption tank 120 is provided with a gas collection tank 110 in the shape of a lower chamber so that carbon dioxide is absorbed and the remaining biogas is collected, and the gas collection tank 110 has a biogas outlet through which biogas is discharged. (111) is provided.

A closed blocking surface 243 is formed between the gas collection tank 110 and the effluent storage tank 240 to prevent movement between the gas collection tank 110 and the effluent storage tank 240. The gas collection tank 110 and the effluent storage tank 240 have the same shape and are arranged in opposite directions around the blocking surface 243. That is, it has the smallest cross section at the blocking surface 243 and the cross section gradually increases as it moves away from the blocking surface 243.

The first effluent water from which the ammonia gas is separated in the ammonia gas production tank 200 is transferred to the carbon dioxide absorption tank 100 through the effluent pipe 250 by its own weight.

The ammonia gas production tank 200 forms a time and space for the wastewater to fall from the top to the paddle 220 and degassing the ammonia gas, and the first effluent discharged through the effluent storage tank 240 is ammonia from the wastewater. has been removed.

The paddle 220 can be attached to the inner wall of the treatment tank 210 in a detachable state, and the present invention uses only the paddle 220 without a heating facility to remove ammonia gas due to the turbulence and drop of wastewater. It becomes possible. The paddle 220 can be combined in various ways, such as male and female combination, bolt combination, etc.

The first effluent discharged from the ammonia gas production tank 200 flows into the bottom of the carbon dioxide absorption tank 100 under its own weight without a driving pump, and the biogas (including carbon dioxide) discharged from the anaerobic digestion tank (not shown) is supplied by the supply pump ( It flows into the acid stone 140 at the bottom of the carbon dioxide absorption tank 100 through (not shown).

The diffuser 140 includes a plurality of supply pipes 141, and each supply pipe 141 extending inside the main absorption tank 120 is provided with a plurality of through holes 142 to allow bio-acids to flow into the diffuser 140. Gas is supplied into the first effluent water within the main absorption tank 120.

Since the acid stone extends between the strong base first effluent to supply biogas, it is preferable to be made of a material that is resistant to corrosion, such as ceramic.

The first effluent water transferred from the ammonia gas production tank 100 falls and flows into the carbon dioxide absorption tank 100 from the lower side, and at this time, the biogas transferred through the supply pump flows into the carbon dioxide absorption tank 100. The first effluent is neutralized by absorbing carbon dioxide in the biogas and becomes the second effluent. In other words, the strongly basic first effluent becomes neutral second effluent by injecting biogas generated after anaerobic treatment of livestock manure without the injection of separate chemicals.

In the present invention, in order to lengthen the contact time between carbon dioxide and the first effluent and lower the non-contact ratio, the carbon dioxide is discharged from the inside of the first effluent stored in the lower part of the carbon dioxide absorption tank 100.

The carbon dioxide absorption tank 100 and the ammonia gas production tank 200 of the present invention form one housing. The effluent storage tank 240 forming the lower part of the ammonia gas production tank 200 and the gas collection tank 110 forming the upper part of the carbon dioxide absorption tank 100. It has an opposite shape centered on the blocking surface 243 and has a concave shape. In the present invention, an upper cover 245 and a lower cover 115 are provided on the outer surfaces of the effluent storage tank 240 and the gas collection tank 110, respectively, so that one housing can be seen as a whole rather than having this concave shape. The upper cover 245 and lower cover 115 are made of a rectangle with the same shape as the main absorption tank 120 disposed below. When the effluent storage tank 240 and the gas collection tank 110 are surrounded by the upper cover 245 and the lower cover 115, the present invention The hybrid biogas production system 10 has an overall rectangular parallelepiped shape.

Meanwhile, hydrogen sulfide in the biogas is removed through gas-liquid contact between the transferred biogas and the first effluent water with a pH of 11 or higher. Hydrogen sulfide exists in an ionic state (dissolved) in bases above pH 10, and in a gaseous state in acids below pH 7. The present invention uses carbon dioxide in the biogas discharged from anaerobic treatment of livestock waste instead of adding a separate chemical to lower the basic first effluent to neutral, and reduces hydrogen sulfide in biogas in the process of lowering the basic first effluent to neutral. Additional benefits arise from the elimination of .

The first effluent flowing into the carbon dioxide absorption tank can be reused as neutral second effluent by lowering the pH to pH 11 or higher, so the pH is lowered in the carbon dioxide absorption tank 100 using carbon dioxide in the biogas flowing in from the anaerobic digestion tank. .

At this time, in the carbon dioxide absorption tank 100, carbon dioxide is dissolved in the first effluent water, lowering the pH, thereby generating neutral second effluent water, and as hydrogen sulfide is removed, the methane ratio is relatively increased and highly nitrified biogas is generated. That is, the methane of the biogas discharged from the upper part of the carbon dioxide absorption tank 100 is lower than the biogas that contacts the first effluent water from which ammonia has been removed and carbon dioxide is absorbed, lowering the pH, and hydrogen sulfide is removed and flowing into the carbon dioxide absorption tank 100. The ratio becomes higher.

In this way, when biogas flows into the carbon dioxide absorption tank 100, the carbon dioxide is dissolved and the first effluent water becomes a neutral second effluent water, and hydrogen sulfide, a corrosive gas, is removed (desulfurized) to produce high-purity biogas with a relatively high proportion of methane. Gas comes out. In this way, in the process of lowering the pH of the first effluent to neutral, if the first effluent with a pH of 11 or higher comes into contact with biogas, that is, gas-liquid contact, an additional benefit occurs in that hydrogen sulfide in the biogas is removed.

Accordingly, the present invention can remove hydrogen sulfide and prevent problems caused by corrosion of pipes and equipment due to hydrogen sulfide.

The second effluent water discharged from the carbon dioxide absorption tank 100 has ammonia, carbon dioxide, and hydrogen sulfide removed from the second outflow hole 125 below the main absorption tank 120, and uses a separate effluent pump (not shown). It is discharged.

Therefore, the hybrid biogas generation system 10 of the present invention has an ammonia gas production tank at the top and a carbon dioxide absorption tank directly below, so that the biogas and wastewater discharged from the anaerobic treatment of livestock manure can be stored in a single housing. It is effective in removing ammonia through ammonia degassing and absorbing carbon dioxide in biogas.

In the present invention, ammonia can be degassed by falling in an ammonia gas production tank by gravity, and the first effluent water from which ammonia has been removed from the ammonia gas production tank at the top is supplied to the carbon dioxide absorption tank without a separate pump to degas the ammonia and remove the first strong base. There is an advantage in energy savings when changing the effluent to neutralized secondary effluent.

The present invention provides a series of small-sized treatment tanks side by side, supplies wastewater to each, and installs a paddle, which is a corrugated inclined plate, downward in the horizontal direction inside each treatment tank to form a plurality of paddles in which the inflow wastewater is formed in a zigzag pattern. There is an advantage in that the residence time is prolonged as the particles fall and move due to their own weight, allowing for smooth degassing of ammonia.

The present invention provides a plurality of paddles with a concavo-convex corrugated upper surface inclined downward in the longitudinal direction inside a rectangular-shaped digestion tank, so that the inflow wastewater alternates between drop movement and uneven movement, and ammonia is removed from the plurality of digestion tanks. Since the first effluent from which gases have been removed is stored in one effluent storage tank and dropped into the carbon dioxide absorption tank, ammonia degassing efficiency is high and the amount of supply to the carbon dioxide absorption tank can be controlled.

10: Hybrid biogas generation system
100: Carbon dioxide absorption tank
110: gas collection tank
111: biogas outlet 115: lower cover
120: main absorption tank
125: Second outflow hole
140: acid stone
141: supply pipe 142: through hole
200: Ammonia gas production tank
210: small processing tank
215: wastewater inlet 216: ammonia gas outlet
220: Paddle
221: Small padded noodles 221a: One side 221b: Thawed noodles
222: Plane surface 223: Irregularity
240: Runoff water storage tank
241: first upper surface 242: second upper surface 243: blocking surface
245: Top cover
250: Runoff water pipe
251: first outflow hole 252: first inflow hole

Claims (8)

An ammonia gas production tank 200, which receives wastewater from livestock manure treated in an anaerobic digestion tank, is placed at the top, and a carbon dioxide absorption tank 100, which receives biogas treated in the anaerobic digestion tank and discharged as gas, is placed at the bottom. In the hybrid biogas production system,
The ammonia gas production tank 200 includes a plurality of rectangular cross-sectional treatment tanks 210 with open bottoms spaced apart from each other and arranged consecutively;
At the lower part of the treatment tank 210, an effluent water storage tank 240 is provided, which has an upper-lower narrow shape with a closed lower end, and into which the first effluent water treated in the treatment tank 210 falls and is stored;
A carbon dioxide absorption tank 100 having a rectangular cross-section perpendicular to the treatment tank 210 is provided below the effluent storage tank 240;
An effluent pipe 250 is provided to vertically connect the lower part of the effluent storage tank 240 and the lower part of the carbon dioxide absorption tank 100 to supply the first effluent water to the carbon dioxide absorption tank 100;
The first effluent and biogas flow into the lower part of the carbon dioxide absorption tank 100, and flow into opposite horizontal surfaces, respectively;
Hybrid biogas generation system
According to paragraph 1,
The plurality of treatment tanks 210 have the same shape and size;
Each treatment tank 210 is
A plurality of wastewater inlets 215 protruding into the treatment tank 210 are provided on the upper side in a horizontal direction, and an ammonia gas outlet 216 through which ammonia gas is discharged is provided at the top;
Hybrid biogas generation system.
According to paragraph 1,
A plurality of rectangular paddles 220 are provided inside the treatment tank 210;
Each paddle 220 has a rectangular shape forming four sides of a small paddle surface 221 with a small length and a large paddle surface 222 with a long length;
The paddle surface 221 has one side (221a) coupled to the inner wall of the treatment tank 210 and the other side (221b) spaced apart from the inner wall of the treatment tank 210, and the paddle surface 222 has both sides. It is coupled to the inner wall of the treatment tank 210;
The paddle 220 has three sides closed by the inner wall of the treatment tank 210 and one side open;
Hybrid biogas generation system.
According to paragraph 3,
The paddle 220 has irregularities formed on its upper surface, and the large paddle surface 222 is inclined downward from one surface 221a coupled to the inner wall of the small paddle surface of the treatment tank 210;
Each paddle 220 is spaced apart up and down, and one side 221a of the adjacent paddle surface 221 is formed in the opposite direction inside the treatment tank 210.
Hybrid biogas generation system.
According to paragraph 1,
The effluent storage tank 240 has a first upper surface 241 that is in contact with the inside of the treatment tank 210 open, and a second upper surface 242 that is not in contact with the treatment tank 210 is closed;
A first outflow hole 251 coupled to the outflow pipe 250 is formed on one side of the lower part;
Hybrid biogas generation system.
According to paragraph 2,
The carbon dioxide absorption tank 100 includes a rectangular main absorption tank 120;
The main absorption tank 120 has a first inlet hole 252 formed on one lower side to receive the first effluent water from the effluent storage tank 240, and the other side of the lower side into which biogas generated from anaerobic treatment of livestock waste flows into. A mountain stone 140 is placed;
A gas collection tank 110 in the shape of a lower chamber is provided on the upper part of the main absorption tank 120 to collect biogas;
The gas collection tank 110 is provided with a biogas outlet 111 through which biogas is discharged;
Hybrid biogas generation system.
According to clause 6,
A closed blocking surface 243 is formed between the gas collection tank 110 and the effluent storage tank 240 to prevent movement;
The gas collection tank 110 and the effluent storage tank 240 have the same shape and are arranged in opposite directions around the blocking surface 243;
Hybrid biogas generation system.
According to clause 6,
The acid stone 140 is
Comprising a supply pipe 141 extending into the carbon dioxide absorption tank 100 and a plurality of through holes 142 disposed in the supply pipe 141.
Hybrid biogas generation system.