Background
The harmless treatment modes of the household garbage mainly include incineration, landfill and composting. Compared with the latter two, the incineration method can realize the reduction and the resource of the household garbage, is a harmless method which is more suitable for the development requirements of the times, has higher social value and economic value, and becomes one of the garbage treatment modes which are vigorously pursued in China at present. However, municipal solid waste in China has the characteristics of high kitchen waste content and high water content, and the incineration calorific value of the solid waste is far lower than the incineration economic calorific value (7000kJ/kg), so that the direct incineration often causes the problems of insufficient combustion, higher cost, low efficiency, overproof pollutant emission and the like. Therefore, the high kitchen waste needs to be subjected to pre-dehydration treatment before incineration, so that the water content of the high kitchen waste is effectively reduced, and the incineration calorific value of the high kitchen waste is improved.
The main components of the domestic garbage comprise degradable substances such as kitchen wastes, paper, textile, bamboo and wood and inert substances such as plastics, rubber, slag, soil, glass, metal and the like. The kitchen waste refers to garbage generated in activities such as daily life and food processing, and comprises discarded vegetable leaves, leftovers, fruit peels, eggshells, tea leaves, bones and the like. Domestic waste in developed countries in Europe and America is mainly composed of paper components, and the content (wet basis) of the domestic waste is more than 30%, while the content (wet basis) of kitchen waste is generally less than 30%, and the domestic waste is called as 'low kitchen waste'. The moisture content of paper is low compared to the kitchen waste components, which results in low kitchen waste with an initial moisture content (wet basis) of typically less than 40%. Domestic waste in developing countries is based on kitchen waste with a content (wet basis) of up to 40% or more, and is called "high kitchen waste". Because the water content (wet basis) of the fresh kitchen waste components is generally over 74 percent, the initial water content (wet basis) of the high kitchen waste is as high as 40-65 percent.
The existing domestic garbage pre-dehydration device mostly adopts mechanical compression dehydration equipment, such as a spiral mechanical compression dehydrator, a hydraulic dehydrator and the like. On one hand, however, leachate generated after extrusion by mechanical compression dewatering equipment is difficult to be completely discharged, and the liquid outlet of the device is not thorough. On the other hand, the mechanical compression dehydration equipment has short compression time, uneven distribution of compressive stress in the extrusion process, no fermentation and degradation function on high kitchen garbage and single overall function, so that the dehydration rate is low and the thermal value requirement of incineration disposal is difficult to achieve.
Chinese patent application document CN111306899A discloses a dehydration treatment device for kitchen garbage, which comprises a stirring mechanism for preliminarily dehydrating and stirring kitchen garbage, and a stirring mechanism for stirring the kitchen garbage rightwards, wherein the stirring mechanism stirs the stirring chamber for stirring the kitchen garbage, the stirring mechanism stirs the stirring chamber for stirring the garbage, the stirring chamber is communicated with an extrusion chamber for mechanical compression dehydration, and a gravity pressing block is arranged on the upper side of the extrusion chamber for mechanical compression dehydration.
Chinese patent application CN110000195A discloses a kitchen waste treatment system with active negative pressure collection, which comprises a motor, a reducer, a clutch, a crushing device, a belt transmission mechanism, a dehydrator, a connecting sleeve, a conveying pipe and a negative pressure part, wherein the output shaft of the motor is mechanically connected with the reducer, the reducer is connected with the crushing device through the clutch, the lower part of the crushing device is connected with the dehydrator through the connecting sleeve, and the lower part of the dehydrator is connected with the negative pressure part through the conveying pipe; the mechanical connection has belt drive mechanism on reducing mechanism's the driving shaft, and the transmission shaft of hydroextractor is connected to belt drive mechanism below, and negative pressure portion includes liquid storage bucket, solenoid valve, presss from both sides the membrane valve, goes vacuum pump station, trachea, adjusting bolt, adjusting spring, lead wire screw, trimmer casing, lower trimmer, compression diaphragm, diaphragm casing, top, goes up trimmer, bracing piece and backup pad, retrieves filtrating through the negative pressure.
The prior art has at least the following disadvantages:
1. leachate generated after extrusion is difficult to be completely discharged, and the effluent of the garbage treatment device is not thorough;
2. the compression time is short, and the distribution of the compressive stress in the extrusion process is uneven, so that the dehydration efficiency of the garbage is not high;
3. the garbage treatment method has no fermentation and degradation function on kitchen garbage, has single integral function and lower dehydration rate, and is difficult to ensure that the treated garbage meets the requirement of heat value for incineration disposal.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a high kitchen garbage pre-dehydration treatment device, which is characterized in that garbage is continuously and uniformly compressed and dehydrated for a long time by utilizing an air pressure loading mode of an air bag pressure stabilizing and loading system, the garbage is subjected to enzymolysis through cellulase and pectinase to assist in accelerating dehydration, percolate is promoted to be discharged from the device by utilizing a negative pressure technology, and meanwhile, a constant-temperature ventilation system is adopted to provide constant-temperature air for a pre-dehydration treatment bin, so that proper conditions can be provided for microbial aerobic degradation in the garbage. The invention has the characteristics of full extrusion, thorough liquid discharge, high dehydration rate, easy realization, low cost and the like. Meanwhile, the high kitchen waste pre-dehydration treatment method provided by the invention combines aerobic degradation dehydration and continuous mechanical compression dehydration technologies, thereby realizing high-efficiency dehydration pretreatment of the high kitchen waste. Meanwhile, the pressure in the air bag is controlled by the air pump and the air pressure meter, so that the air bag continuously applies a set pressure to the garbage, and the garbage is uniformly extruded.
The invention provides a high kitchen waste pre-dehydration treatment device, which comprises:
the device comprises a pre-dehydration treatment bin, an air bag pressure stabilizing loading system, a constant temperature ventilation system and a gas-liquid separation type liquid collecting system;
the upper part of one side wall of the pre-dehydration treatment bin is provided with a feeding pipe, and the lower part of the other side wall is provided with a sealing door;
the pre-dehydration treatment bin is used for accommodating high kitchen waste sprayed with an enzyme solution, and the enzyme solution comprises cellulase and pectinase;
the air bag pressure stabilizing and loading system comprises an air pump, a pressure regulating valve, an air pressure gauge and an air bag, wherein the air pump is connected with the air pressure gauge, the air pressure gauge is connected with the pressure regulating valve, the pressure regulating valve is connected with the air bag, and the air bag pressure stabilizing and loading system controls the pressure in the air bag to ensure that the air bag is inflated and expanded to continuously and mechanically compress and dewater the high kitchen garbage;
the air bag is arranged at the top in the pre-dehydration treatment bin; the bottom structure of the air bag is sequentially provided with a rubber layer, an inner geotechnical cloth layer, a steel wire mesh layer and an outer geotechnical cloth layer from inside to outside;
inlets of air inlet pipes of the constant-temperature ventilation system are uniformly distributed on the side wall of the pre-dehydration treatment bin, and the constant-temperature ventilation system is used for providing constant-temperature air for the pre-dehydration treatment bin;
the gas-liquid separation type liquid collecting system is connected with the bottom of the pre-dehydration treatment bin and is used for creating a negative pressure environment in the pre-dehydration treatment bin and promoting gas generated by aerobic degradation of microorganisms in the garbage and percolate extruded from the garbage to be discharged from the device.
Preferably, the bottom in the pre-dehydration treatment bin is provided with a guide and discharge plate, a water outlet pipe is arranged below the guide and discharge plate, and the water outlet pipe is connected with the gas-liquid separation type liquid collection system.
Preferably, constant temperature ventilation system includes air pump, heater, thermometer and air-supply line No. two, No. two air pumps the heater with the thermometer all with the air-supply line is connected, No. two air pumps pass through the air-supply line is connected the heater, the heater passes through the air-supply line with the thermometer is connected.
Preferably, the number of the inlets of the air inlet pipe connected to the side wall of the pre-dehydration treatment bin is at least 15.
Preferably, the gas-liquid separation type liquid collection system comprises a gas outlet end, a liquid outlet end, a gas-liquid separation tank and a negative pressure pump, wherein the top of the gas-liquid separation tank is connected with one end of the negative pressure pump, the other end of the negative pressure pump is the gas outlet end, one end of the bottom of the gas-liquid separation tank is connected with the bottom of the pre-dehydration treatment bin, and the other end of the bottom of the gas-liquid separation tank is the liquid outlet end.
The invention provides a pre-dehydration treatment method using the high kitchen waste pre-dehydration device, which comprises the following steps:
s100: discharging the high kitchen garbage into the pre-dehydration treatment bin through a feeding pipe;
s200: spraying the enzyme solution into the waste, the enzyme solution comprising cellulase and pectinase;
s300: starting the air bag pressure stabilizing and loading system, and adjusting the air pressure in the air bag through the pressure adjusting valve and the air pressure gauge to ensure that the air bag continuously applies 200-300 kPa pressure on the top of the garbage and keeps stable, wherein the process is continued until the dehydration is finished;
s400: starting the constant-temperature ventilation system, and continuously introducing air heated by a heater into the pre-dehydration treatment bin; simultaneously starting the gas-liquid separation type liquid collection system, opening the gas outlet end, closing the liquid outlet end, discharging gas generated by aerobic degradation of microorganisms in the garbage and redundant gas introduced by the constant-temperature ventilation system from the gas outlet end, and temporarily storing percolate extruded from the garbage at the bottom of the gas-liquid separation tank for T1 time;
s500: closing the constant-temperature ventilation system, keeping the gas-liquid separation type liquid collection system running, closing the gas outlet end, opening the liquid outlet end, and discharging percolate temporarily stored at the bottom of the gas-liquid separation tank from the liquid outlet end, wherein the process lasts for T2 time;
s600: alternately implementing the steps S400 and S500, and carrying out dehydration treatment for T3 time under the combined action of continuous mechanical compression and aerobic degradation to finish dehydration.
Preferably, the enzyme solution is prepared by adopting a two-enzyme method, and is prepared from cellulase, pectinase and water according to a mass ratio of 1 (0.2-1) to 100.
Preferably, the T1 is 5-6 hours, the T2 is 0.5-1 hour, and the T3 is at least 3 days.
Preferably, the constant-temperature ventilation system adjusts the temperature of the air flow through the heater and the thermometer, and continuously introduces air of 40 +/-3 ℃ into the pre-dehydration treatment bin, and the ventilation rate is 100-200L/kg dry garbage/day.
Preferably, the weight of the enzyme solution is 1-3% of the weight of the garbage in the pre-dehydration treatment bin.
Compared with the prior art, the invention has the following beneficial effects:
(1) the invention utilizes the air pressure loading mode to continuously and uniformly compress and dewater the high kitchen garbage for a long time, and the dewatering rate is higher;
(2) the high kitchen waste is subjected to enzymolysis through cellulase and pectinase to assist in accelerating dehydration;
(3) the invention utilizes the negative pressure technology to promote the percolate to be discharged from the device, and the liquid is discharged thoroughly;
(4) the constant-temperature ventilation system is used for providing constant-temperature air for the pre-dehydration treatment bin, and suitable conditions are provided for aerobic degradation of microorganisms in the garbage;
(5) the invention mechanically extrudes the garbage by utilizing the air bags respectively comprising the rubber layer, the inner geotechnical cloth layer, the steel wire mesh layer and the outer geotechnical cloth layer from inside to outside, thereby not only ensuring uniform stress distribution during extrusion and achieving the purpose of uniform compression and dehydration, but also ensuring that the air bags are not easy to corrode and prolonging the service life of the air bags.
Detailed Description
The following detailed description of embodiments of the invention refers to the accompanying drawings of fig. 1-7.
The invention provides a high kitchen waste pre-dehydration treatment device, which comprises:
the device comprises a pre-dehydration treatment bin 1, an air bag pressure stabilizing and loading system, a constant temperature ventilation system and a gas-liquid separation type liquid collecting system;
a feeding pipe 2 is arranged at the upper part of one side wall of the pre-dehydration treatment bin 1, and a sealing door 3 is arranged at the lower part of the other side wall;
the pre-dehydration treatment bin 1 is used for containing high kitchen waste sprayed with enzyme solution, and the enzyme solution comprises cellulase and pectinase;
one of the characteristics of the high kitchen waste is that the content of fruits and vegetables is high, and the main components of the cell wall of plant cells are cellulose and pectin. The two are selected from biological enzymes in order to disrupt the cell wall and thereby promote adequate dewatering of the high kitchen waste. The two enzymes are selected according to the characteristics of the high kitchen waste, so that the pertinence is stronger, the high kitchen waste is decomposed more comprehensively and thoroughly, and the cost can be saved.
The air bag pressure stabilizing and loading system comprises an air pump 6, a pressure regulating valve 7, a barometer 8 and an air bag 9, wherein the air pump 6 is connected with the barometer 8, the barometer 8 is connected with the pressure regulating valve 7, the pressure regulating valve 7 is connected with the air bag 9, and the air bag pressure stabilizing and loading system controls the pressure in the air bag 9 to ensure that the air bag 9 is inflated and expanded to continuously and mechanically compress and dewater garbage;
the air bag 9 is arranged at the top in the pre-dehydration treatment bin 1; the bottom structure of the air bag 9 is sequentially provided with a rubber layer 18, an inner geotechnical cloth layer 19, a steel wire mesh layer 20 and an outer geotechnical cloth layer 21 from inside to outside;
the rubber layer 18 is arranged on the innermost layer, so that the air bag 9 can expand downwards to extrude garbage after being inflated; and the air bag 9 is adopted for extrusion, so that the distribution of the pressure stress is more uniform during extrusion.
An inner geotextile layer 19 is disposed adjacent to the rubber layer 18 for purposes including:
1. as the cushion rubber layer 18, the steel wire mesh layer 20 is prevented from directly contacting the rubber layer 18, so that the hard part of the steel wire mesh layer 20 punctures the rubber layer 18.
2. The geotextile 19 has good tensile property and is not easy to damage when being expanded together with the air bag 9.
The outside of geotechnological cloth layer 19 including wire net layer 20 sets up, and the purpose includes:
1. the steel wire mesh is hard, and the steel wire mesh layer is arranged outside the inner geotechnical cloth layer 19, so that garbage can be compressed downwards uniformly.
2. The rubber layer 18 is protected, and sharp objects in the garbage are prevented from puncturing and damaging the rubber layer 18.
3. The steel wire has good tensile property and is not easy to damage when being expanded together with the air bag 9.
Outer geotextile layer 21 is arranged at the outermost layer for the purposes of:
1. the steel wire mesh layer 20 is protected by buffering, so that the garbage is prevented from directly contacting with the steel wire mesh to corrode the steel wire.
2. The geotextile has good tensile property and is not easy to damage when expanding together with the air bag 9.
The air bag has the advantages of air pressure loading:
1. the air is used as the working medium, the working medium is easy to obtain, the cost is low (the cost of purchasing and storing hydraulic oil needs to be considered in hydraulic loading), the air used in the air bag is discharged into the atmosphere, the treatment is convenient, and no pollution is caused.
2. Because the viscosity of air is very small (about ten-thousandth of the dynamic viscosity of hydraulic oil), the flow resistance in the pipe is small, and the pressure loss is small, the centralized air supply and the delivery are convenient.
3. Compared with hydraulic pressure, the pneumatic reaction is fast, the action is fast, the maintenance is simple, and the pipeline is not easy to block.
Inlets of air inlet pipes 13 of the constant temperature ventilation system are uniformly distributed on the side wall of the pre-dehydration treatment bin 1, and the constant temperature ventilation system is used for providing constant temperature air for the pre-dehydration treatment bin 1;
the purpose of adopting a constant-temperature ventilation system for ventilation is to provide aerobic conditions for the aerobic degradation of microorganisms in the garbage, and the purpose of constant temperature is to provide proper temperature for the aerobic degradation of the microorganisms and the enzymolysis of biological enzymes.
The purpose of accelerating aerobic degradation is as follows: the aerobic degradation can promote the quick decomposition of kitchen waste components in the high kitchen waste household garbage, so that the water in the kitchen waste components is easier to compress and extrude; in addition, the microorganism aerobic fermentation can generate a large amount of heat, and the water content of the garbage can be effectively reduced through high-temperature evaporation and ventilation entrainment.
The gas-liquid separation type liquid collecting system is connected with the bottom of the pre-dehydration treatment bin 1 and is used for creating a negative pressure environment in the pre-dehydration treatment bin 1 and promoting gas generated by aerobic degradation of microorganisms in the garbage and percolate extruded from the garbage to be discharged from the device.
The first air pump, the pressure regulating valve and the barometer of the air bag pressure stabilizing and loading system are arranged outside the pre-dehydration treatment bin 1, the air bag 9 is arranged in the pre-dehydration treatment bin 1, and all components of the air bag pressure stabilizing and loading system are connected through a ventilation pipeline.
After the air bag pressure stabilizing loading system is started, the air bag 9 is ventilated by the first air pump 6, the air bag 9 is inflated and then expands downwards to extrude garbage so as to achieve the purpose of uniform compression and dehydration, the barometer 8 is used for measuring the air pressure in the air bag 9, and when the set air pressure is reached, the pressure regulating valve 7 is controlled to close the ventilation pipeline to stop the inflation; when the air pressure measured by the air pressure meter is lower than the set air pressure, the pressure regulating valve 7 is controlled to be opened, and the air bag 9 is continuously inflated to the set air pressure.
As a preferred embodiment, a guide and discharge plate 4 is arranged at the bottom in the pre-dehydration treatment bin 1, a water outlet pipe 5 is arranged below the guide and discharge plate 4, and the water outlet pipe 5 is connected with the gas-liquid separation type liquid collection system, so that the gas-liquid separation type liquid collection system can promote the leachate to be discharged from the high kitchen garbage pre-dehydration device through the water outlet pipe by using a negative pressure technology.
As a preferred embodiment, the constant temperature ventilation system comprises an air pump 10, a heater 11, a thermometer 12 and an air inlet pipe 13, wherein the air pump 10, the heater 11 and the thermometer 12 are all connected with the air inlet pipe 13, the air pump 10 is connected with the heater 11 through the air inlet pipe 13, and the heater 11 is connected with the thermometer 12 through the air inlet pipe 13.
The components of the constant temperature ventilation system are all arranged outside the pre-dehydration treatment bin 1 and are connected with the pre-dehydration treatment bin 1 through an air inlet pipe 13. All components of the constant temperature ventilation system are connected through ventilation pipelines.
After the constant temperature ventilation system is started, the second air pump 10 is used for ventilating the pre-dehydration treatment bin 1, so that aerobic conditions are provided for microbial aerobic degradation inside garbage, and the heater 11 and the thermometer 12 are used for heating air and controlling temperature, so that proper temperature is provided for microbial aerobic degradation and biological enzyme enzymolysis.
In a preferred embodiment, the number of the inlets of the air inlet pipe 13 connected to the side wall of the pre-dehydration treatment bin 1 is at least 15.
As a preferred embodiment, the gas-liquid separation type liquid collection system comprises a gas outlet end 15, a liquid outlet end 16, a gas-liquid separation tank 14 and a negative pressure pump 17, wherein the top of the gas-liquid separation tank 14 is connected with one end of the negative pressure pump 17, the other end of the negative pressure pump 17 is the gas outlet end 15, one end of the bottom of the gas-liquid separation tank 14 is connected with the bottom of the pre-dehydration treatment bin 1, and the other end of the bottom of the gas-liquid separation tank 14 is the liquid outlet end 16.
The gas-liquid separation type liquid collecting system utilizes a negative pressure pump 17 connected with the air outlet end 15 to manufacture a negative pressure environment. Since the gas density is low, the gas outlet end 15 is arranged at the upper side, the liquid density is high, the liquid flows at the lower side under the influence of gravity, and the liquid outlet end 15 is arranged at the lower side.
The components of the gas-liquid separation type liquid collecting system are all arranged outside the pre-dehydration treatment bin 1 and are connected with the pre-dehydration treatment bin 1 through a water outlet pipe 15.
After the gas-liquid separation type liquid collecting system is started, the negative pressure pump 17 is started, a negative pressure environment is manufactured in the pre-dehydration treatment bin 1, the gas outlet end 15 and the liquid outlet end 16 are alternately opened, the leachate is discharged from the liquid outlet end 16 due to the negative pressure environment, and the waste gas is discharged from the gas outlet end 15.
The device of the invention is not provided with an exhaust pipe independently, and the exhaust end of the gas-liquid separation type liquid collecting system is used for exhausting air.
The invention provides a pre-dehydration treatment method using the high kitchen waste pre-dehydration device, which comprises the following steps:
s100: discharging the high kitchen garbage into the pre-dehydration treatment bin 1 through a feeding pipe 2;
s200: spraying the enzyme solution into the waste, the enzyme solution comprising cellulase and pectinase;
s300: starting the air bag pressure stabilizing and loading system, and adjusting the air pressure in the air bag through the pressure adjusting valve and the air pressure gauge to ensure that the air bag continuously applies 200-300 kPa pressure on the top of the garbage and keeps stable, wherein the process is continued until the dehydration is finished;
figure 5 shows the relationship between the air bag pressure and the dewatering rate using different pressures in one embodiment of the pre-dewatering process of the present invention.
Wherein,
sample preparation: typical domestic garbage in Hangzhou city has kitchen residue content of about 60% and initial water content (wet basis) of about 65%;
the test conditions are as follows: the temperature is 40 plus or minus 3 ℃, the ventilation rate is 100L/kg dry garbage/day, and the covering stress is 50, 100, 200, 300 and 400 kPa;
it can be seen from the figure that: along with the increase of the overlying stress, the dehydration rate of the household garbage is gradually improved; when the overlying stress exceeds 200kPa, the efficiency of improving the dehydration rate of the domestic garbage is not high. Therefore, in consideration of economic cost and other factors, the optimal overlying stress range is recommended to be 200-300 kPa.
S400: starting the constant-temperature ventilation system, and continuously introducing air heated by a heater into the pre-dehydration treatment bin; simultaneously starting the gas-liquid separation type liquid collection system, opening the gas outlet end, closing the liquid outlet end, discharging gas generated by aerobic degradation of microorganisms in the garbage and redundant gas introduced by the constant-temperature ventilation system from the gas outlet end, and temporarily storing percolate extruded from the garbage at the bottom of the gas-liquid separation tank for T1 time;
s500: closing the constant-temperature ventilation system, keeping the gas-liquid separation type liquid collection system running, closing the gas outlet end, opening the liquid outlet end, and discharging percolate temporarily stored at the bottom of the gas-liquid separation tank from the liquid outlet end, wherein the process lasts for T2 time;
s600: alternately implementing the steps S400 and S500, and carrying out dehydration treatment for T3 time under the combined action of continuous mechanical compression and aerobic degradation to finish dehydration.
In a preferred embodiment, the enzyme solution is prepared by adopting a two-enzyme method, and the enzyme solution is prepared from cellulase, pectinase and water according to a mass ratio of 1 (0.2-1) to 100.
In a preferred embodiment, the T1 is 5 to 6 hours, the T2 is 0.5 to 1 hour, and the T3 is at least 3 days.
In a preferred embodiment, the constant temperature ventilation system adjusts the temperature of the air flow through the heater and the thermometer, and continuously introduces air with the temperature of 40 +/-3 ℃ into the pre-dehydration treatment bin, wherein the ventilation rate is 100-200L/kg dry garbage/day.
FIG. 6 is a graph showing the relationship between the air input into the constant temperature ventilation system and the degradation rate at different temperatures according to an embodiment of the pre-dehydration treatment method of the present invention.
Wherein,
sample preparation: the typical domestic garbage in Hangzhou city has kitchen residue content of 60% and initial water content (wet basis) of 65%
The test conditions are as follows: the covering stress is 10kPa, the ventilation rate is 100L/kg dry garbage/day, and the temperature is 25 ℃, 30 ℃, 35, 40, 45 and 50 DEG C
As can be seen from the figure: along with the rise of the temperature, the degradation rate of the household garbage is gradually improved; when the temperature exceeds 40 ℃, the degradation rate of the household garbage is not obviously improved. Therefore, in consideration of economic cost and the like, an optimum temperature control range of 40 ± 3 ℃ is suggested.
FIG. 7 shows the relationship between aeration rate and degradation rate of the constant temperature ventilation system in one embodiment of the pre-dehydration treatment method of the present invention.
Wherein,
sample preparation: the typical domestic garbage in Hangzhou city has kitchen residue content of 60% and initial water content (wet basis) of 65%
The test conditions are as follows: covering with 10kPa, the temperature is 40 +/-3 ℃, and the ventilation rate is 25, 50, 100, 200 and 400L/kg dry garbage/day;
as can be seen from the figure: when the ventilation rate is increased from 25L/kg dry garbage/day to 200L/kg dry garbage/day, the degradation rate of the domestic garbage is gradually increased, and the effect is best when 100-200L/kg dry garbage/day; when the aeration rate is further increased to 400L/kg dry garbage/day, the domestic garbage degradation rate is slightly reduced compared with 200L/kg dry garbage/day. Therefore, considering the economic cost, the degradation effect and other factors, the optimal ventilation rate control range is recommended to be 100-200L/kg dry garbage/day.
In a preferred embodiment, the weight of the enzyme solution is 1-3% of the weight of the high kitchen garbage in the pre-dehydration treatment bin.
Example 1
The high kitchen waste pre-dehydration treatment apparatus according to the present invention will be described in detail below according to an embodiment of the present invention.
The invention provides a high kitchen waste pre-dehydration treatment device, which comprises:
the device comprises a pre-dehydration treatment bin 1, an air bag pressure stabilizing and loading system, a constant temperature ventilation system and a gas-liquid separation type liquid collecting system;
a feeding pipe 2 is arranged at the upper part of one side wall of the pre-dehydration treatment bin 1, and a sealing door 3 is arranged at the lower part of the other side wall;
the pre-dehydration treatment bin 1 is used for containing high kitchen waste sprayed with enzyme solution, and the enzyme solution comprises cellulase and pectinase;
the air bag pressure stabilizing and loading system comprises an air pump 6, a pressure regulating valve 7, a barometer 8 and an air bag 9, wherein the air pump 6 is connected with the barometer, the barometer is connected with the pressure regulating valve, the pressure regulating valve is connected with the air bag, and the air bag pressure stabilizing and loading system controls the pressure in the air bag 9 to ensure that the air bag 9 is inflated and expanded to continuously and mechanically compress and dewater garbage;
the air bag 9 is arranged at the top in the pre-dehydration treatment bin 1; the bottom structure of the air bag 12 is sequentially provided with a rubber layer 18, an inner geotechnical cloth layer 19, a steel wire mesh layer 20 and an outer geotechnical cloth layer 21 from inside to outside;
inlets of air inlet pipes 13 of the constant temperature ventilation system are uniformly distributed on the side wall of the pre-dehydration treatment bin 1, and the constant temperature ventilation system is used for providing constant temperature air for the pre-dehydration treatment bin 1; 15 inlets of the air inlet pipe 13 on each side wall of the pre-dehydration treatment bin 1;
the constant-temperature ventilation system comprises a second air pump 10, a heater 11, a thermometer 12 and an air inlet pipe 13, wherein the second air pump 10, the heater 11 and the thermometer 12 are all connected with the air inlet pipe 13, the second air pump 10 is connected with the heater 11 through the air inlet pipe 13, and the heater 11 is connected with the thermometer 12 through the air inlet pipe 13;
the gas-liquid separation type liquid collecting system is connected with the bottom of the pre-dehydration treatment bin 1 and is used for creating a negative pressure environment in the pre-dehydration treatment bin 1 and discharging gas generated by aerobic degradation of microorganisms in the garbage and percolate extruded from the garbage from the device;
the gas-liquid separation type liquid collection system comprises a gas outlet end 15, a liquid outlet end 16, a gas-liquid separation tank 14 and a negative pressure pump 17, wherein the top of the gas-liquid separation tank 14 is connected with one end of the negative pressure pump 17, the other end of the negative pressure pump 17 is the gas outlet end 15, one end of the bottom of the gas-liquid separation tank 14 is connected with the bottom of the pre-dehydration treatment bin 1, and the other end of the bottom of the gas-liquid separation tank 14 is the liquid outlet end 16;
the bottom in the pre-dehydration treatment bin 1 is provided with a guide and discharge plate 4, a water outlet pipe 5 is arranged below the guide and discharge plate 4, and the water outlet pipe 5 is connected with the gas-liquid separation type liquid collection system, so that the gas-liquid separation type liquid collection system utilizes a negative pressure technology to promote leachate to be discharged from the high kitchen waste pre-dehydration device through the water outlet pipe 5.
Example 2
The method for pre-dewatering high-kitchen-waste according to the present invention will be described in detail below.
The invention provides a pre-dehydration treatment method using the high kitchen waste pre-dehydration device, which comprises the following steps:
s100: discharging the high kitchen garbage into the pre-dehydration treatment bin 1 through a feeding pipe 2;
s200: spraying the enzyme solution into the waste, the enzyme solution comprising cellulase and pectinase; the weight of the enzyme solution is 1-3% of the weight of the garbage in the pre-dehydration treatment bin 1, the enzyme solution is prepared by adopting a double-enzyme method, and the enzyme solution is prepared from cellulase, pectinase and water according to the mass ratio of 1 (0.2-1) to 100;
s300: starting the air bag pressure stabilizing and loading system, and adjusting the air pressure in the air bag 9 through the pressure adjusting valve 7 and the barometer 8, so that the air bag 9 continuously applies 200kPa pressure on the top of the garbage and keeps stable, and the process is continued until the dehydration is finished; the pressure can be adjusted by a pressure adjusting valve 7, the air bag 9 is continuously inflated downwards after being ventilated, and the pressure stabilizing loading is started until the air bag touches the top of the garbage pile body, so that the influence is avoided even if the garbage pile does not reach the top;
s400: starting the constant temperature ventilation system, and continuously introducing air heated by a heater 11 into the pre-dehydration treatment bin 1; simultaneously starting the gas-liquid separation type liquid collection system, opening the gas outlet end 15, closing the liquid outlet end 16, discharging gas generated by aerobic degradation of microorganisms in the garbage and redundant gas introduced by the constant-temperature ventilation system from the gas outlet end 15, discharging the gas and the redundant gas into the waste gas purification system, and temporarily storing percolate extruded from the garbage at the bottom of the gas-liquid separation tank for T1 time, wherein the T1 time is 6 hours;
the constant-temperature ventilation system adjusts the temperature of air flow through the heater 11 and the thermometer 12, and continuously introduces air of 40 ℃ into the pre-dehydration treatment bin 1, wherein the ventilation rate is 150L/kg dry garbage/day;
s500: closing the constant-temperature ventilation system, keeping the gas-liquid separation type liquid collection system running, closing the gas outlet end, opening the liquid outlet end, discharging percolate temporarily stored at the bottom of the gas-liquid separation tank from the liquid outlet end, and discharging the percolate into a percolate treatment system, wherein the process lasts for T2 time, and T2 is 1 hour;
s600: alternately implementing the steps S400 and S500, and carrying out dehydration treatment for T3 time under the combined action of continuous mechanical compression and aerobic degradation to complete dehydration, wherein the T3 is 4 days.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention shall fall within the protection scope of the present invention.