SUMMERY OF THE UTILITY MODEL
The utility model aims to provide a horizontal type rotary mixing anaerobic (HRM) digester.
In order to achieve the above purpose, the technical scheme of the utility model is as follows:
the utility model relates to a horizontal rotary mixing anaerobic (HRM) digester, which comprises a feeding area, a mixed heating area, a rotary mixing fermentation area, a sedimentation area, a clean water tank and a reflux tank, wherein the feeding area, the mixed heating area, the rotary mixing fermentation area and the sedimentation area are connected in sequence, the sedimentation area is respectively connected with the clean water tank and the reflux tank,
the feeding area is used for temporarily storing and stirring the entering high-concentration organic wastewater, adding microorganisms into the wastewater, then inputting the stirred wastewater into the mixed heating area,
the mixed heating area is used for heating the stirred wastewater and inputting the heated wastewater into the rotary mixing fermentation area,
the rotary mixing fermentation area is used for carrying out anaerobic fermentation on the heated wastewater and inputting the fermented wastewater into the precipitation area,
the sedimentation zone is used for carrying out solid-liquid separation on the fermented wastewater to obtain sediment and supernatant, the supernatant is input into the clean water tank, the sediment is input into the reflux tank,
the clean water tank is used for temporarily storing the supernatant and returning the supernatant to the feeding area to circulate the treatment steps or outputting the supernatant meeting the environmental protection requirement,
the reflux pool is used for recovering sediments in the wastewater and returning collected sediments to the feeding area.
Preferably, the feeding area and the mixing and heating area are both provided with stirring devices.
Preferably, the rotary mixing fermentation zone comprises unpowered biogas stirring equipment and at least one anaerobic reactor, the anaerobic reactor is of a fully closed structure, and the unpowered biogas stirring equipment is positioned in the anaerobic reactor.
Preferably, the unpowered biogas stirring equipment comprises a rectangular tank body, a biogas return pipe and a gas one-way valve, wherein the rectangular tank body is a closed space formed by a top surface, a bottom surface and four side surfaces, at least one side surface is provided with a flow guide hole which is rectangular, the edge of the flow guide hole extends into the closed space to form a flow guide groove, the tail end of the flow guide groove is closed, the top of the flow guide groove is communicated with the closed space of the rectangular tank body, one end of the biogas return pipe is fixedly connected with the top surface of the rectangular tank body, the biogas return pipe is communicated with the rectangular tank body and is used for introducing biogas into the rectangular tank body,
the gas one-way valve is arranged on the methane return pipe and is used for enabling methane to flow only in the direction of entering the rectangular tank body.
Preferably, the top of the settling zone is provided with an effluent weir which is used for introducing supernatant overflow of the settling zone into a clean water tank, and the bottom of the settling zone is provided with a flow guide pipe which is communicated with the bottom of the reflux tank and is used for inputting sediments into the reflux tank.
Preferably, a slow descending slope is arranged below the sedimentation zone and is used for collecting sediments (namely anaerobic bacteria).
Preferably, the settling zone is a cuboid, the number of the slow descending slopes is four, the slow descending slopes are distributed at four corners of the settling zone, the top of each slow descending slope is connected with the inner wall of the settling zone, the bottom of each slow descending slope is connected with the bottom of the settling zone, and a space is reserved between the bottoms of two adjacent slow descending slopes.
Preferably, each slow descending slope adopts an inclined plate to constitute, and the inclination of every inclined plate is 35 ~ 45, honeycomb duct one end is located the settling zone bottom, and the other end is located the reflux pool bottom.
Preferably, a three-phase separator is arranged between the slow descending slope and the water outlet weir and used for separating sediment, water and gas in the settling zone, so that constant pressure in the settling zone and stable operation of equipment are ensured.
Preferably, biogas collecting pipes are arranged above the rotary mixing fermentation zone and the sedimentation zone and used for collecting and outputting biogas above the rotary mixing fermentation zone and the sedimentation zone.
The utility model has the advantages that:
the utility model provides a horizontal type mixes anaerobism (HRM) digester soon compares with current vertical anaerobism digester, the utility model discloses add unpowered agitated vessel in mixing the fermentation district soon, the disturbance through this equipment makes the rivers that mix in the fermentation district soon be the whirl state, can make the substrate in the sewage and the abundant contact digestion of microorganism, improves the digestion capacity. After the biogas is treated by the digester, the yield of the biogas is increased by 15%, and the treatment rate of suspended matters is increased to 80-90%. The utility model discloses need not to add equipment such as three-phase separator and water-locator in mixing the fermentation district soon, and avoided marsh gas to leak, can be with the marsh gas output of collecting or for anaerobic system provides the heat source.
The equipment has the advantages of low investment, long service cycle, low maintenance rate and low treatment cost. And a water distribution system, a baffle plate, a sectional water distribution system and the like are not required to be arranged, and the problems of water distribution blockage, equipment aging corrosion and flow velocity influence are avoided.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be described in detail below. It is to be understood that the embodiments described are only some embodiments of the invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.
In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be described in detail below. It is to be understood that the embodiments described are only some embodiments of the invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.
The embodiment of the utility model relates to a horizontal whirlpool anaerobism (HRM) digester that mixes, as shown in figure 1, this digester includes feeding zone 1, mixes the heating zone 2, revolves and mixes fermentation zone 3, settling zone 4, clean water basin 5 and reflux pool 6. The feeding area 1, the mixed heating area 2, the rotary mixing fermentation area 3 and the sedimentation area 4 are sequentially connected, and the sedimentation area 4 is respectively connected with the clean water tank 5 and the reflux tank 6. The structure and function of each reaction zone are as follows:
[ feed zone ]
The feeding area 1 is used for temporarily storing and stirring the entering high-concentration organic wastewater, adding microorganisms into the wastewater, and then inputting the stirred wastewater into the mixed heating area 2. In addition, because the sediment collected by the recovery tank and the supernatant collected by the clean water tank flow back to enter the feeding area 1, the feeding area 1 also has the functions of mixing the backflow matter with the entering high-concentration organic wastewater, stabilizing the wastewater concentration in the wastewater, and adjusting, buffering and diluting the wastewater. The dashed line in fig. 1 represents a suspended stirring device, which may be a paddle stirrer or an anchor stirrer. Located in the feed zone 1 is a first suspended stirring device 11.
The utility model provides a HRM digester can only handle dirty waste water body, especially high concentration organic waste water, for example plant's waste water, coking waste water, pharmacy waste water, weaving/printing and dyeing waste water, petroleum/chemical industry waste water. The suspended matter content (ss value) in the wastewater is 100-500 mg/L, and the COD value is 1000-50000 mg/L. The utility model discloses in use the waste water of plant as the example, explain its processing procedure. The waste water of the farm mainly contains urine, partial excrement and flushing water, belongs to high-concentration organic sewage, and has high content of suspended matters and ammonia nitrogen. After the untreated wastewater enters a natural water body, the contents of solid suspended matters, organic matters and microorganisms in the water body are increased, the physical, chemical and biological community composition of the water body is changed, and the water quality is deteriorated. The sewage also contains a large amount of pathogen microorganisms which are diffused and spread through the water body and harm the health of people and livestock.
[ Mixed temperature rise region ]
The mixing temperature rising area 2 is used for heating the stirred wastewater and inputting the heated wastewater into the rotary mixing fermentation area 3. In order to realize the functions, a second suspension type stirring device 21 and a first heating coil 22 are arranged in the mixed heating area 2, and the wastewater above the mixed heating area 2 overflows into the rotary mixing fermentation area 3. The temperature is increased within a certain temperature range, the organic matter removal rate is increased, and the gas production rate is increased. The rapid changes and fluctuations in temperature are generally considered to be detrimental to the anaerobic digestion process. The heating temperature can be properly selected according to the types of the added microorganisms, so as to promote the digestion reaction of the substrate and the microorganisms. The utility model discloses in, the heating temperature who mixes heating zone 2 is 28 ~ 30 ℃.
[ Rotary mixing fermentation zone ]
The rotary mixing fermentation zone 3 is used for carrying out anaerobic fermentation digestion reaction on the heated wastewater and inputting the wastewater after fermentation digestion into the precipitation zone 4. The anaerobic fermentation reaction mainly comprises the following four stages:
(1) a hydrolysis stage: due to the large molecular volume of the macromolecular organic matter, the macromolecular organic matter can not directly pass through the cell wall of anaerobic bacteria, and needs to be decomposed into small molecules by extracellular enzymes outside microorganisms. Typical organic substances in wastewater, such as cellulose, are decomposed by cellulase into cellobiose and glucose, starch is decomposed into maltose and glucose, and protein is decomposed into short peptides and amino acids. The decomposed small molecules can enter cells through cell walls to be decomposed in the next step.
(2) And (3) acidification stage: the small molecule organic matter enters the cell body to be converted into simpler compounds and is distributed outside the cell, and the main product of the stage is Volatile Fatty Acid (VFA), and meanwhile, partial products such as alcohols, lactic acid, carbon dioxide, hydrogen, ammonia, hydrogen sulfide and the like are generated.
(3) An acetic acid production stage: at this stage, the product of the last step is further converted into acetic acid, carbonic acid, hydrogen and new cellular material.
(4) A methanogenesis stage: at this stage, acetic acid, hydrogen, carbonic acid, formic acid and methanol are all converted to methane, carbon dioxide and new cellular material. This phase is also the most important phase of the whole anaerobic process and the rate-limiting phase of the whole anaerobic reaction process.
In one embodiment of the present invention, the rotary mixing fermentation zone 3 comprises an unpowered biogas stirring device 31 and an anaerobic reactor 32, the anaerobic reactor 32 is a totally enclosed structure, and a water inlet is provided at the bottom of the anaerobic reactor 32. The unpowered biogas stirring device 31 is located inside the anaerobic reactor 32.
As shown in FIG. 1, a plurality of unpowered biogas stirring devices 31 are arranged in parallel in an anaerobic reactor 32, and the anaerobic reactor 32 has a gallery type structure. As can be seen from the figure 2, the second heating coils 321 are symmetrically arranged on the two sides of the anaerobic reactor 32, biogas enters the unpowered biogas stirring device 31, and water flow in the tank forms a spiral mixing plug flow type effect through the exhaust disturbance effect of the unpowered biogas stirring device 31, so that substrates and microorganisms are fully fused, the existence of dead corners is avoided, and the wastewater treatment effect is improved.
[ unpowered biogas stirring device ]
As shown in fig. 3, the unpowered biogas mixing device 31 comprises a rectangular tank 311, a biogas return pipe 312 and a gas check valve 313. Wherein,
rectangular tank 311 constitutes the enclosure by top surface, bottom surface and four sides, is equipped with water conservancy diversion hole 3110 on at least one side, and water conservancy diversion hole 3110 is the rectangle, and its edge extends to forming guiding gutter 3111 in the enclosure, and the end of guiding gutter 3111 is sealed, and the top of guiding gutter 3111 is linked together with rectangular tank 311's enclosure.
As can be seen from fig. 3 and 4, the depth of the guide holes 3110 extending inward is smaller than the width of the rectangular can 311. The reason for this design is as follows: when water is injected into the anaerobic reactor 32, the water level rises from the bottom and gradually enters the region between the anaerobic reactor 32 and the unpowered biogas stirring device 31. When water enters the diversion holes 3110 and also enters the diversion trench 3111, and when the water level reaches the top of the diversion trench 3111, the air pressure inside the rectangular tank 311 is greater than the water pressure in the anaerobic reactor 32 because gas (air or methane) is stored inside the rectangular tank 311. Although the top of the guiding groove 3111 is connected to the enclosed space of the rectangular tank 311, water cannot continuously enter the rectangular tank 311 through the top of the guiding groove 3111. The water level in the anaerobic reactor 32 continues to rise until the rectangular tank 311 is submerged, thus forming a continuous vacuum zone within the rectangular tank 311, i.e., the lightly shaded region in FIG. 4. At this time, water can be injected until the biogas return pipe 312 is partially or completely submerged, and then biogas is introduced into the rectangular tank 311 through the biogas return pipe 312. When the rectangular tank 311 is filled with biogas and the pressure in the rectangular tank 311 is continuously increased, the excess biogas escapes from the top of the baffle-trough 3111 to form bubbles, and the liquid material in the anaerobic reactor 32 is stirred during the rising process.
Compared with the method of directly forming the diversion holes 3110 on the side surface of the rectangular tank body 311, the additional diversion groove 3111 can keep the vacuum state in the rectangular tank body 311 after the water surface continuously rises and submerges the diversion holes 3110, and the biogas is not influenced to escape from the upper side of the diversion groove 3111. Therefore, more water can be added into the anaerobic reactor 32, the contact area of the biogas and the liquid material is increased, and the degradation efficiency of the biogas is further improved.
In a specific embodiment of the present invention, the projection of the guiding groove 3111 on the bottom surface of the rectangular tank 311 may be rectangular. As shown in fig. 3 and 4, it can be understood that the cross section of the guide groove 3111 along the direction a is rectangular. The guide groove 3111 having a rectangular cross section or a projection has a first connection surface, a second connection surface, and a third connection surface connected in sequence, and a top surface of the guide groove 3111 is not closed in an open state. The first connecting surface and the third connecting surface are both connected to the side surface of the rectangular can 311, and the second connecting surface forms the end of the guiding groove 3111. The second connecting surface is parallel to the side of the rectangular can 311 where the guiding hole 3110 is located, and the first connecting surface is parallel to the third connecting surface.
In an embodiment of the present invention, the guiding groove 3111 and the rectangular tank 311 have a common bottom surface. If the guiding gutter 3111 and the rectangular tank 311 are not at the same bottom, the rising height of the bubbles in the anaerobic reactor 32 is shortened, and the bottom of the guiding gutter 3111 needs to be processed separately, which increases the difficulty of manufacturing the device.
One end of the biogas return pipe 312 is fixedly connected with the top surface of the rectangular tank 311, the other end is connected with an external device, and the biogas return pipe 312 is communicated with the rectangular tank 311 and is used for introducing biogas into the rectangular tank 311.
The gas check valve 313 is disposed on the biogas return pipe 312, and functions to allow biogas to flow only in the direction of entering the rectangular tank 311.
The working principle of the rotary mixing fermentation zone 3 is as follows: water is injected into the anaerobic reactor 31 through a water inlet at the bottom until the water level reaches the position below the gas one-way valve 313, and a space required by the independent air chamber 322 is reserved above the water level of the anaerobic reactor 31. The rectangular can 311 has a continuous vacuum region therein. The biogas collected by the biogas chamber enters the rectangular tank 311 through the biogas return pipe 312, and when the rectangular tank 311 is filled with biogas and the pressure in the rectangular tank 311 is continuously increased, the excess biogas escapes from the top of the guide groove 3111 to form bubbles, and the escape direction of the biogas is the direction indicated by the arrow. And the stirring action of the liquid material in the anaerobic reactor 32 is realized in the rising process.
[ settling, clean water and reflux tanks ]
The settling zone 4 is used for separating solid and liquid of the fermented wastewater and separating microorganisms in the wastewater from a water body. The microorganism in the wastewater is precipitated to the bottom of the precipitation zone 4 to obtain precipitate and supernatant, the supernatant is input into a clean water tank 5, and the precipitate is input into a reflux tank 6.
Further, as shown in fig. 1, the top of the settling zone 4 is provided with an effluent weir 41, which functions to introduce the overflow of the settling zone 4 into the clean water tank 5. The clean water tank 5 is used for temporarily storing the supernatant, and after the upper limit of the volume is reached, the supernatant can be returned to the feeding area 1 to circulate the treatment steps, and the supernatant reaching the urban comprehensive discharge standard can be output and discharged. The weir is a water passing structure in hydraulic engineering, water does not pass when being lower than the weir crest, and the weir only plays the manger plate effect this moment, if the upper reaches continue to come water, the upstream water level has just been raised to the weir, when the water level was higher than the weir crest, water just overflowed from the weir crest, and this is exactly the meaning of weir. The utility model discloses a set up the weir plate at the settling zone top to realize overflow and play water function. The weir plate can be made into a plate with a rectangular notch or a triangular notch by adopting a wood plate, a metal plate or a cement plate. The utility model discloses be equipped with the sawtooth backplate in play mill weir 41 both sides, can guarantee balanced play water.
In an embodiment of the present invention, a slow descending slope 43 is provided below the settling zone 4 for collecting the sediment. As shown in fig. 4, the settling zone 4 is a rectangular body having a top surface, a bottom surface, and four side surfaces. The number of the slow descending slopes 43 is four, the top of each slow descending slope 43 is connected with the inner wall of the side face of the settling zone 4, the bottom of each slow descending slope is connected with the bottom face of the settling zone 4, and a space is reserved between the bottoms of every two adjacent slow descending slopes 43. Furthermore, each slow descending slope 43 is composed of a sloping plate, and the inclination angle of each sloping plate is 35-45 degrees.
The bottom of the settling zone 4 is provided with a guide pipe 42, and the guide pipe 42 is communicated with the bottom of the reflux pool 6 and is used for inputting sediments into the reflux pool 6. The reflux pool 6 is used for recovering sediments (mainly microorganisms, namely anaerobic bacteria added into the feeding area 1) in the wastewater, and returning the collected sediments to the feeding area 1, so that the microorganisms can be recycled. In order to transfer the sediment as much as possible, one end of the draft tube 42 is located at a position where the bottom surface of the settling zone 4 is not in contact with the slow descending slope 43, and the other end of the draft tube 42 is located at the bottom of the return pond 6. When the microorganism sediments are settled in the settling zone 4, part of the microorganism sediments directly settle to the bottom of the settling zone 4, part of the microorganism sediments settle on the slow descending slope 43, and the microorganism sediments move along the inclined angle to fall to the bottom of the settling zone 4, and then directly enter the reflux pool 6 through the draft tube 42.
In an embodiment of the present invention, a three-phase separator 44 is disposed between the slow descending slope 43 and the water outlet weir 41 for separating the sediment, water and gas in the settling zone 4, thereby ensuring the constant pressure and stable operation of the equipment in the settling zone. The three-phase separator 44 may be a balanced pressure type three-phase separator described in patent CN206089191U, which includes a gas chamber, a gas collecting duct and a flow guide plate. The bottom end of the air chamber is open, the top of the air chamber is sealed, the side wall of the air chamber is provided with a biogas diversion hole, the air chamber is communicated with the gas collecting pipeline through the biogas diversion hole, and collected biogas is discharged outside. The guide plate is arranged in the air chamber, and the bottom end of the guide plate is arranged at the lower edge of the biogas guide hole. When the device is used, the constant-pressure three-phase separator is placed in biogas slurry or other fermentation liquid, and the generated methane gas is gathered in the gas chamber. When the volume of the gas in the gas chamber exceeds the volume of the part above the methane diversion hole in the gas chamber, the gas can enter the gas collection pipeline through the methane diversion hole, and the gas quantity in the gas chamber keeps a constant value, so that the pressure in the gas chamber is ensured to be constant and not influenced by anaerobic reaction and fluctuation of actual working conditions, the problems of loss of anaerobic flora, fluctuation of effective volume of a system, difficulty in methane output and blockage of a methane pipe network caused by buoyancy of the whole working conditions of the constant pressure type three-phase separator are reduced, and the stable treatment efficiency of the settling zone 4 is ensured and improved.
In an embodiment of the present invention, a biogas collecting pipe (not shown in the figure) is disposed above the rotary mixing fermentation zone 3 and the sedimentation zone 4, and is used for collecting and outputting biogas above the two zones. As can be seen from fig. 1 and 4, in the rotary mixing fermentation zone 3, an independent air chamber 322 is arranged above the anaerobic reactor 32, a biogas collecting and discharging chamber 45 is arranged above the effluent weir 41 of the settling zone 4, and both the independent air chamber 322 and the biogas collecting and discharging chamber 45 are connected with a biogas collecting pipe to collect and output biogas in the rotary mixing fermentation zone 3 and the settling zone 4.
The horizontal rotary mixing anaerobic (HRM) digester of the utility model can be provided with a plurality of rotary mixing fermentation areas 3, so that the high-concentration organic wastewater is subjected to anaerobic fermentation reaction in the plurality of rotary mixing fermentation areas 3. After the output biogas is desulfurized by the desulfurization equipment, the biogas can be conveyed to the boiler equipment through the circulating fan to provide heat energy for the whole reaction system, and the redundant biogas can also be conveyed to the biogas generator to realize electric energy output.
Compared with the prior art, the horizontal rotary mixing anaerobic (HRM) digester has the highest height of only 6 meters, so the horizontal rotary mixing anaerobic (HRM) digester has low manufacturing cost and is suitable for being constructed in any area. The unpowered methane stirring equipment adopted in the rotary mixing fermentation area 3 can improve the degradation efficiency of a biochemical system, and solve the problems of sludge loss, low treatment rate, incomplete contact between substrates and microorganisms and the like caused by nonuniform water distribution in the prior art, and has stable treatment effect and high treatment rate. The material flowing mode in the system is a mixed spiral plug flow type and an independent backflow system is arranged to prevent the sludge loss. Due to the adoption of the independent air chamber and the methane collecting and discharging chamber, the methane collecting and gas production rate is improved by 10-15%.
Taking the treatment of farm wastewater as an example, the working principle of the horizontal rotary mixing anaerobic (HRM) digester is as follows:
(1) feeding wastewater of a farm into a feeding area 1, adding microorganisms into the wastewater, stirring the wastewater by using a suspension type stirring device, possibly collecting materials of a clean water tank 5 and a backflow tank 6 in the process, feeding the collected materials into the feeding area 1, mixing the wastewater with the collected materials in the feeding area 1, and then inputting the stirred wastewater into a mixed heating area 2;
(2) heating and stirring the wastewater in a mixed heating area 2, and inputting the heated wastewater into a rotary mixing fermentation area 3;
(3) anaerobic fermentation is carried out on the wastewater in the rotary mixing fermentation zone 3, biogas generated after fermentation is collected by an air chamber above the rotary mixing fermentation zone 3 and enters unpowered biogas stirring equipment 31 to realize stirring and reaction promotion of substrates and microorganisms in the wastewater, and the fermented wastewater is input into a precipitation zone 4;
(4) the solid-liquid-gas separation of the wastewater occurs in the sedimentation zone 4, the microorganisms in the wastewater are precipitated to the bottom of the sedimentation zone 4 to obtain precipitate and supernatant, the supernatant is overflowed and input into the clean water tank 5 through the effluent weir 41, and the precipitate is input into the reflux tank 6 through the draft tube 42;
(5) the supernatant is temporarily stored in the clean water tank 5, and if the ss value of the supernatant meets the environmental protection requirement, the supernatant can be discharged or used as industrial water. Returning the supernatant to the feeding zone 1 for recycling the treatment step if the ss value of the supernatant does not meet the environmental protection requirement;
the sediment, which is mainly anaerobic microorganisms, can be periodically returned to the feed zone 1 from the sediment collected in the return basin 6.
(6) The biogas generated in the rotary mixing fermentation zone 3 enters an independent gas chamber 322 above the anaerobic reactor 32, the biogas generated in the sedimentation zone 4 enters a biogas collecting and discharging chamber 45 above the effluent weir 41, and the generated biogas is collected and output through a biogas collecting pipe and is used for boiler heating and power generation after being desulfurized.
The HRM process can only treat sewage and wastewater, and the biogas yield of the existing UASB anaerobic fermentation process is usually determined according to the influent water concentration (CODr/kg/m)3) Calculated, generally 0.35m per kg of CODR3Biogas. And by adopting the HRM process of the utility model, each kilogram of CODr can generate 0.4-0.6 m3The biogas can be used as fuel for heating the boiler, and provides a heat source for the HRM system. Compared with the inlet water, the outlet water can degrade 75 to 90 percent of the solid content and can reach the content of the solid in national townsFirst class a emission standard.
The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present invention, and all should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.