Method and device for carbon source of organic garbage leachate sewage

Abstract

The application discloses a method and device for carbon source of organic garbage leachate sewage. The application uses sodium tetraphenylborate to realize rapid precipitation removal of ammonium ions in sewage, provides carbon-nitrogen ratio of sewage, and improves biological availability. The method uses the precipitation reaction between sodium tetraphenylborate and ammonia ions in aqueous solution as the basic principle, and then selects static separation according to the properties of the precipitate. The water body can be stored as a carbon source or directly added to the water treatment process in the form of a carbon source. After the precipitate is collected, dewatered, and recovered by heating alkali, the precipitate can be recycled as a precipitant, and the released concentrated ammonia gas can be collected for industrial production. The method has high reaction efficiency, low interference degree, high controllability of carbon-nitrogen ratio, recyclable main reagent, low theoretical operation cost, obvious removal effect on the color of sewage, and high industrial value of the discharged carbon source water body.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of organic garbage leachate sewage carbonization method and device, it is related to wastewater comprehensive treatment and resource utilization.The present application more specifically, it intends to reduce the concentration of ammonium ion in solution by using sodium tetraphenylborate precipitate ammonium ion principle, improve the carbon-nitrogen ratio of wastewater, substantially improve the biological availability of organic matter in wastewater, promote wastewater as carbon source resource utilization. BACKGROUND

[0002] The nitrogen and phosphorus emission standards of municipal wastewater treatment plant are high, and there are problems such as large variation of influent, complex water quality, high nitrogen and phosphorus content, and lack of internal carbon source in wastewater during the actual operation of wastewater nitrogen and phosphorus removal in municipal wastewater treatment system, which requires a large amount of carbon source during the actual wastewater treatment process, especially during the denitrification process and the phosphorus removal process, which requires sufficient carbon source. At present, the main external carbon source is small molecule alcohol or acid such as methanol, sodium acetate and glucose, which has high cost. According to the experience of similar engineering treatment of landfill leachate, 4-5 kg of food grade glucose needs to be added per ton of leachate, and the unit price is 5000 yuan per ton. Each ton of leachate water needs to spend 20-25 yuan on carbon source. In addition to high cost, due to the fluctuation of influent water quality, quantitative carbon source addition can easily lead to problems such as reagent waste, sludge production increase, and nitrogen and phosphorus removal not meeting the standards.

[0003] Considering the above problems of external carbon source in industrial production as a comparison, it is of great significance to find a low-cost and stable carbon source. Current research shows that paper, corn cob and other materials can be used as external carbon source after a series of treatments, but the actual stability or utilization effect is relatively poor. Another waste resource utilization, kitchen waste hydrolysis acidification wastewater has very high organic matter concentration, which can improve the biodegradability of wastewater and improve the denitrification efficiency of wastewater. However, the chemical composition of this carbon source is relatively complex, and the carbon-nitrogen ratio is difficult to control at the target value, and the controllability is low. In addition, residual oil will inhibit the denitrification effect in the long-term operation. SUMMARY

[0004] The present application provides an organic garbage leachate sewage carbonization method from the perspective of wastewater resource utilization, which uses sodium tetraphenylborate to precipitate ammonium ion, reduces the molar amount of ammonia nitrogen in solution, promotes the increase of carbon-nitrogen ratio of solution, meets the carbon source utilization standard, and promotes its resource utilization.

[0005] The specific technical solutions adopted by the present application are as follows:

[0006] In a first aspect, the present application provides an organic garbage leachate sewage carbonization method, which comprises:

[0007] S1, the aqueous solution of sodium tetraphenylborate is added to the leachate wastewater of organic garbage as an ammonia nitrogen removal agent, and solid-liquid separation is carried out after sufficient stirring and mixing to obtain upper clear liquid and lower milky white aqueous precipitate;

[0008] S2, the lower milky white aqueous precipitate is taken out for dehydration treatment, the liquid part produced by dehydration is combined with the upper clear liquid as a carbon source required for adjusting the carbon-nitrogen ratio in the wastewater treatment process, the precipitate produced by dehydration is dissolved in an organic solvent, and an excess of a strong alkali solution is added for heating and condensation, the organic solvent is recovered from the condensate, and sodium tetraphenylborate is recovered from the precipitate part left after volatilization of the organic solvent.

[0009] As a preferred embodiment of the first aspect, the addition amount of the ammonia nitrogen removal agent should be such that the concentration of the precipitate in the mixed system after sufficient stirring and mixing is between 70 mmol / L and 120 mmol / L.

[0010] As a preferred embodiment of the first aspect, the solid-liquid separation is achieved by standing for 5-10 h.

[0011] As a preferred embodiment of the first aspect, the organic solvent is acetone.

[0012] As a preferred embodiment of the first aspect, the strong alkali solution is a sodium hydroxide aqueous solution.

[0013] As a preferred embodiment of the first aspect, the precipitate produced by dehydration needs to be prewashed, dried and crushed before being dissolved in the organic solvent.

[0014] As a preferred embodiment of the first aspect, in the heating and condensation process, the heating temperature is 60-90℃, the heating is performed until the organic solvent is completely volatilized to leave the precipitate, the volatilized organic solvent is recovered through a condensing device during the heating and condensation process, the escaped ammonia gas is collected through a tail gas collecting device, and finally the sodium tetraphenylborate in the precipitate is collected.

[0015] As a preferred embodiment of the first aspect, after the ammonia nitrogen removal agent is added to the leachate wastewater of organic garbage, a flocculant and a coagulant aid need to be further added to strengthen the precipitation.

[0016] As a preferred embodiment of the first aspect, the industrial purity of sodium tetraphenylborate in the sodium tetraphenylborate aqueous solution is 99%.

[0017] In a second aspect, the present application provides an organic garbage leachate wastewater carbon source device, which comprises a uniform feeding device, a stirring device, a reaction tank, an overflow sedimentation tank, a buffer tank, a dehydration device, a membrane filtration system and a storage tank.

[0018] The reaction tank serves as the main body of the reaction, the side wall thereof is provided with a water inlet and a water outlet, and the bottom precipitate area is provided with a sludge discharge port.

[0019] The overflow sedimentation tank is used as the main body of secondary sedimentation, and the side wall is provided with a water inlet and a water outlet, and the bottom sedimentation area is provided with a sludge discharge port;

[0020] The uniform feeding device is located above the reaction tank and is provided with a plurality of discharge holes for uniformly adding the aqueous solution of sodium tetraphenylborate as an ammonia nitrogen remover to the leachate sewage.

[0021] The stirring device is used for fully stirring and mixing the ammonia nitrogen remover and the leachate sewage in the reaction tank.

[0022] The water inlet of the reaction tank is used for injecting the leachate sewage of organic garbage, the water outlet is connected to the water inlet of the overflow sedimentation tank, the supernatant preliminarily separated after fully stirring and mixing in the reaction tank is injected into the overflow sedimentation tank for secondary sedimentation, the supernatant overflowed from the overflow sedimentation tank is sent to the membrane filtration system through the water outlet for membrane filtration, and the liquid after membrane filtration is temporarily stored in the storage tank for use as a carbon source required for adjusting the carbon-nitrogen ratio in the sewage treatment process.

[0023] The lower layer of milky white water-containing sediment collected at the bottom of the reaction tank and the overflow sedimentation tank is periodically discharged into the dewatering device through the sludge discharge port, the liquid part generated by dewatering is temporarily stored in the storage tank after being filtered by the membrane filtration system, and the sediment generated by dewatering is sent to the heating and condensation recovery device, and the sodium tetraphenylborate is recovered from the sediment part left after the organic solvent volatilizes.

[0024] As a preferred embodiment of the second aspect, the dewatering device is a cyclone separator or a plate-and-frame filter press.

[0025] Compared with the prior art, the present application has the following advantages:

[0026] (1) The present application uses the method of treating waste with waste, and the leachate sewage of high-organic-content organic garbage is converted into a high-carbon-nitrogen-ratio carbon source by adding sodium tetraphenylborate for sewage denitrification and phosphorus removal.

[0027] (2) The wastewater carbonization method provided by the present application involves fewer reactions, simple operation, strong controllability, rapid reaction time, and the precipitant sodium tetraphenylborate can be recycled and regenerated.

[0028] (3) The wastewater carbon source method provided by the application has less influence on the COD value of the carbon source wastewater, and can remove precipitated impurities and part of the colority in the wastewater through precipitation and adsorption during the treatment process, thereby sufficiently improving the quality of the wastewater as a carbon source, and the quality of the carbon source added after hydrolysis and acidification of the kitchen waste wastewater is better, and the controllability of the carbon-nitrogen ratio is stronger. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 It is a schematic diagram of the steps of an organic garbage leachate wastewater carbon source method.

[0030] Figure 2 It is a structural schematic diagram of an organic garbage leachate wastewater carbon source device.

[0031] In the drawing, the reference signs are: uniform feeding device 1, stirring device 2, reaction tank 3, overflow sedimentation tank 4, buffer tank 5, dewatering device 6, membrane filtration system 7, and storage tank 8. DETAILED DESCRIPTION

[0032] In order to make the above-mentioned objects, features and advantages of the application more apparent and easy to understand, the following will make a detailed description through specific embodiments. In the following description, a large number of specific details are set forth in order to fully understand the application. However, the application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the concept of the application, so the application is not limited by the specific embodiments disclosed below. The technical features in each embodiment of the application can be combined accordingly without conflict.

[0033] The application is based on the perspective of wastewater carbon source resourceization, and aims to provide a waste resource carbon source with strong controllability, stable operation and low cost on the basis of existing problems. The target water body is selected to have a high content of organic matter and a high proportion of ammonia nitrogen to total nitrogen. The main purpose is to improve the carbon-nitrogen ratio of wastewater by removing ammonium ions through precipitation, thereby improving the biodegradability of wastewater. Based on existing research, there are two main principles of ammonia nitrogen precipitation that can be used. One is to remove ammonium ions and also has a removal effect on phosphorus by forming magnesium ammonium phosphate. The other principle is the precipitation of sodium tetraphenylborate and ammonium ions. The latter has the advantage of rapid reaction and only a single chemical reaction occurs. Ammonium ions replace sodium ions in sodium tetraphenylborate to precipitate, and ammonia is released from tetraphenylammonium borate to reduce sodium tetraphenylborate under the condition of alkaline solution heating. The reaction path is simple, and the reaction cost is low. Therefore, the application uses the precipitation reaction between sodium tetraphenylborate and ammonia ions in aqueous solution as the basic principle to reduce the equimolar amount of ammonia nitrogen in the solution, promote the increase of the carbon-nitrogen ratio of the solution, and reach the carbon source utilization standard to promote its resource utilization.

[0034] Example 1

[0035] This embodiment is a pre-experiment, which is used to show the ammonium ion control effect of adding sodium tetraphenylborate to the organic garbage leachate water sample before UASB treatment, so as to prove the feasibility of the principle of the present application. The specific experimental process of this embodiment is as follows:

[0036] Take the UASB water sample before treatment of a certain transfer station containing NH4 + -N (which belongs to organic garbage leachate, the same below) with a concentration of 2300 mg / L, divide it into multiple test tubes, and set 6 groups of parallel samples, each group sets three parallels, the total molar amount of sodium tetraphenylborate added to the test tube and the total molar amount of ammonia nitrogen in the test tube are in the ratio of 6:5, 1:1, 2:3, 1:2, 1:3, and 1:6, mix uniformly, then use 0.45 micron microporous filter paper to filter, take the clear liquid in the bottle to the test tube, because the 6:5 and 1:1 experimental groups may have excessive sodium tetraphenylborate, which has a certain influence on the determination of ammonia nitrogen concentration by sodium reagent ultraviolet spectrophotometry, so after taking out, add excessive 1 g / L potassium chloride solution, record the volume of the added solution, convert the dilution multiple, after sufficient precipitation, use 10000 r / min high-speed centrifugation for 2 min, then take the solution to the test tube. The determination results of sodium reagent ultraviolet spectrophotometry in this embodiment show that the ammonia nitrogen concentrations under the six ratios are 0 mg / L, 0 mg / L, 455 mg / L, 1136 mg / L, 1535 mg / L, and 1904 mg / L, and the removal rates are 100%, 100%, 80.23%, 50.63%, 33.25%, and 17.23%, respectively, excluding the slight error influence of potassium ions in the solution, it basically accords with the theoretical addition ratio. Therefore, it is fully demonstrated that in this water sample treatment system, adding sodium tetraphenylborate can remove the ammonium ions in the leachate wastewater in equimolar amount, so in actual engineering, the concentration of ammonium ions in the water body can be controlled by controlling the amount of sodium tetraphenylborate added according to actual needs, the carbon-nitrogen ratio of the wastewater can be improved, and the carbon-nitrogen ratio demand as a carbon source can be met.

[0037] In addition, for each experimental group of this embodiment, the COD value of the solution before and after the reaction is determined, and after repeated experiments and comparison, it is found that the COD value of the solution after precipitation separation by adding sodium tetraphenylborate is reduced by about 10% compared with 5900 mg / L before, and the COD value reduction is basically the same under multiple sodium tetraphenylborate addition concentrations. Considering multiple factors such as the existence of part of the precipitate in the solution and the problem of significant decrease of the colority of the solution before and after the reaction, the reason for the decrease of the COD value may be that the colority-containing substances in the solution are adsorbed or reacted when the sodium tetraphenylborate precipitate is removed, and part of the precipitate containing COD in the solution is also removed during the precipitation process.

[0038] Embodiment 2

[0039] This embodiment is used to verify the precipitation separation effect of adding sodium tetraphenylborate aqueous solution to the leachate, which sets two different tests of static precipitation and flocculation precipitation.

[0040] The experimental process of the static precipitation method is as follows:

[0041] A certain transit station UASB water sample containing 2300 mg / L NH4 + -N before treatment was taken, and six groups of parallel samples were set up in multiple test tubes, each group was set up in triplicate, the total molar ratio of sodium tetraphenylborate added to the total molar amount of ammonia nitrogen in the test tube was 6:5, 1:1, 2:3, 1:2, 1:3 and 1:6, and the corresponding generated precipitate molar concentration was 164.28 mmol / L, 164.28 mmol / L, 109.52 mmol / L, 82.14 mmol / L, 54.76 mmol / L and 27.38 mmol / L. The precipitation effect of different dosages was compared by using the static precipitation method, and after 8 hours of standing, it was found that the solution supernatant was best clarified at the dosing ratio of 2:3 and 1:2, which was similar to the filtering effect of 10 micron aperture filter paper, and the solution clarification degree showed a downward trend when the amount of sodium tetraphenylborate added was more or less than this amount. The experiment showed that the relationship between the precipitation effect of sodium tetraphenylborate and the precipitation concentration showed a trend of first increasing and then decreasing. Further gradient test results showed that if the static precipitation method is used to remove the precipitate generated by sodium tetraphenylborate and ammonia nitrogen, the dosage of the ammonia nitrogen remover should be such that the precipitate concentration in the mixed system after sufficient stirring and mixing is between 70 mmol / L and 120 mmol / L.

[0042] The experimental process of the flocculation precipitation method is as follows:

[0043] A certain transit station UASB water sample containing 2300 mg / L NH4 + -N before treatment was taken, and an equal volume of 28110 mg / L sodium tetraphenylborate solution was reacted, at which time the molar ratio of NH4 + -N to sodium tetraphenylborate in the mixed system was 2:1, and the theoretical remaining NH4 + -N was 1150 mg / L. According to the results of multiple tests, the remaining ammonia nitrogen concentration in the solution was measured to be 1134 mg / L, and the precipitation flocculation efficiency was high when 100 mg / L of polyaluminum chloride and 100 mg / L of polyacrylamide were added. After standing for 5 hours, the total volume ratio of the precipitate layer reached 42.86%, and the supernatant was highly clarified, with a turbidity similar to that of 0.45 filter paper filtration, and the suspended matter mass was also the same after drying and weighing. After standing for 14 hours, the total volume ratio of the precipitate layer reached 31.25%, and the supernatant was still highly clarified. This shows that if the static precipitation method cannot meet the requirements for sedimentation effect after the ammonia nitrogen remover is added to the organic waste leachate wastewater, flocculants and coagulants can be added to strengthen the precipitation.

[0044] Example 3

[0045] This embodiment is used to verify the precipitation separation effect of the centrifugal precipitation method after adding aqueous sodium tetraphenylborate solution into the percolate.

[0046] Take the water sample containing 2300 mg / L NH4 + The water sample containing 2300 mg / L NH4

[0047] The water sample containing 2300 mg / L NH4 + The water sample containing 2300 mg / L NH4

[0048] Therefore, it is shown that when the precipitation concentration generated by sodium tetraphenylborate and ammonia nitrogen is too high, the centrifugal precipitation method has certain effect, but it is still difficult to achieve the best removal performance. When the method of the present application is applied, it is still necessary to reasonably control the precipitation concentration, that is, the sodium tetraphenylborate dosage is determined according to the sewage volume, ammonia nitrogen molar concentration and target carbon-nitrogen ratio, and preferably the precipitation concentration in the mixed system after mixing is ensured to be between 70 mmol / L and 120 mmol / L, at which time the separation effect by static precipitation is also good. However, if the single addition of carbon-nitrogen ratio cannot be reduced to the target value, multiple additions can be considered for separation to reduce the precipitation concentration generated each time.

[0049] Example 4

[0050] This embodiment is used to show that the carbon source method of the present application can realize the regeneration of sodium tetraphenylborate.

[0051] Take 60 mL of water containing a concentration of 2300 mg / L NH4 + -N, the water sample after reaction with an equal volume of 56220 mg / L sodium tetraphenylborate solution, 0.45 micron microfiltration paper and glass dish drying weight after using 0.45 micron microfiltration paper to filter the water sample, take the precipitate at 80 ℃ drying to the balance weight, record the average mass of 2.1368 g, the recovery rate of the precipitate is 64.28%. Again take the precipitate placed in the mortar to powder, then washed into the ground cone flask with 20 mL of acetone, add 0.5 g of sheet sodium hydroxide reagent and 20 mL of deionized water, dissolve and stir evenly, set the spherical condenser with air as the condensing fluid, place in the electromagnetic heating stirring furnace on 100 ℃ sand bath stirring heating 4 h. During the stirring and heating process, the white precipitate releases yellow insoluble material suspended in the solution. After heating, wait until the solution cools to room temperature, volatilize and condense the acetone, adjust the pH of the water body to about 7-8, add the solution to 2000 mg / L NH4 + -N, the white flocculent precipitate in the solution indicates that the sodium tetraphenylborate is regenerated successfully.

[0052] Take 20 mL of water containing a concentration of 2300 mg / L NH4 + -N, the water sample after reaction with an equal volume of 56220 mg / L sodium tetraphenylborate solution, 0.45 micron microfiltration paper and glass dish drying weight after using 0.45 micron microfiltration paper to filter the water sample, take the precipitate at 80 ℃ drying to the balance weight, record the average mass of 2.1368 g, the recovery rate of the precipitate is 64.28%. Again take the precipitate placed in the mortar to powder, then washed into the ground cone flask with 20 mL of acetone, add 0.5 g of sheet sodium hydroxide reagent and 20 mL of deionized water, dissolve and stir evenly, set the spherical condenser with air as the condensing fluid, place in the electromagnetic heating stirring furnace on 100 ℃ sand bath stirring heating 4 h. During the stirring and heating process, the white precipitate releases yellow insoluble material suspended in the solution. After heating, wait until the solution cools to room temperature, volatilize and condense the acetone, adjust the pH of the water body to about 7-8, add the solution to 2000 mg / L NH4 +- NH4Cl solution in a test tube, add 5 mL volumetric flask regenerated sodium tetraphenylborate solution, each group of three parallel, add 5 mL of the solution of sodium tetraphenylborate configuration, respectively, for calculating the recovery rate. The above solution using 2000 r / min high speed centrifugation 20 min, take supernatant for ammonia nitrogen concentration determination, using sodium reagent UV spectrophotometry, also measured 2000 mg / L NH4 + - NH4Cl solution ammonia nitrogen value, using ammonia nitrogen removal rate to calculate the concentration of sodium tetraphenylborate solution. After the determination, the actual recovery rate of sodium tetraphenylborate is 56.18%.

[0053] Example 5

[0054] This example is used to show the effect of adding sodium tetraphenylborate to organic waste leachate at different processing links.

[0055] Test 1: using a landfill leachate raw water, the ammonia nitrogen concentration is 1128 mg / L NH4 + - N, according to 1:1 molar ratio of sodium tetraphenylborate reagent, after reaction and centrifugal separation, the ammonia nitrogen is basically completely removed, the COD concentration is reduced to a certain extent, the nitrate nitrogen is basically unchanged, and the carbon nitrogen ratio of water body is greatly increased.

[0056] Test 2: using a landfill leachate wastewater treatment process two sedimentation tank effluent, the ammonia nitrogen concentration is 188 mg / L NH4 + - N, according to 1:1 molar ratio of sodium tetraphenylborate reagent, after reaction and centrifugal separation, the ammonia nitrogen is basically completely removed, the COD concentration is basically unchanged, the nitrate nitrogen is basically unchanged, and the carbon nitrogen ratio of water body is greatly increased.

[0057] Test 3: using a landfill leachate wastewater treatment process anoxic tank effluent, the ammonia nitrogen concentration is 1031 mg / L NH4 + - N, according to 1:1 molar ratio of sodium tetraphenylborate reagent, after reaction and centrifugal separation, the ammonia nitrogen is basically completely removed, the COD concentration is basically unchanged, the nitrate nitrogen is basically unchanged, and the carbon nitrogen ratio of water body is greatly increased.

[0058] Test 4: using a certain transfer station concentrated liquid water sample, the ammonia nitrogen concentration is 1191 mg / L NH4 + - N, according to 1:1 molar ratio of sodium tetraphenylborate reagent, after reaction and centrifugal separation, the ammonia nitrogen is basically completely removed, the COD concentration is reduced to a certain extent, the nitrate nitrogen is basically unchanged, and the carbon nitrogen ratio of water body is greatly increased.

[0059] Test 5: using a certain transfer station conditioning tank water sample, the ammonia nitrogen concentration is 948 mg / L NH4 +-N, sodium tetraphenylborate reagent was added in a 1:1 molar ratio. After centrifugal separation, it was determined that ammonia nitrogen was basically completely removed, COD concentration was reduced to a certain extent, nitrate nitrogen was basically unchanged, and the carbon-nitrogen ratio of the water body was greatly increased.

[0060] In the above examples 1-5, the sodium tetraphenylborate added will produce a high-moisture white aqueous precipitate. After removing the solid-liquid separation of this part of the precipitate, the liquid part remaining, and the liquid part produced in the further dehydration process of this high-moisture precipitate, the carbon-nitrogen ratio is high, so theoretically it can be used as a carbon source required for adjusting the carbon-nitrogen ratio in the sewage treatment process.

[0061] Example 6

[0062] In this embodiment, based on the experimental results in the above examples 1-5, a regenerative organic waste leachate sewage carbon source method is designed, the specific steps including:

[0063] S1, the aqueous solution of sodium tetraphenylborate is added to the organic waste leachate sewage as an ammonia nitrogen removal agent, and is fully stirred and mixed for solid-liquid separation (the solid-liquid layering can be completed by standing for 5-10 h, of course, flocculants and coagulants can also be added, or centrifugation and membrane filtration operations can be used), to obtain the upper clear liquid and the lower white aqueous precipitate;

[0064] S2, the white aqueous precipitate is removed for dehydration treatment, the liquid part produced by dehydration is combined with the above-mentioned upper clear liquid as a carbon source required for adjusting the carbon-nitrogen ratio in the sewage treatment process, and the precipitate produced by dehydration (preferably pre-washed, dried and crushed to improve the solubility) is dissolved in an organic solvent (preferably acetone or other organic solvents that can dissolve the precipitate), and an excess of a strong alkali solution (preferably sodium hydroxide aqueous solution, the molar number of sodium hydroxide is preferably 1.1 times the molar amount of sodium tetraphenylborate, with appropriate excess) is added for heating and condensation. Recover the organic solvent from the condensate, and recover the sodium tetraphenylborate from the precipitate left after the organic solvent volatilizes.

[0065] In the above heating and condensation process, the heating temperature is preferably controlled at 60-90°C, and the heating can be performed by water bath or other methods until the organic solvent is completely volatilized to leave the precipitate. The volatilized organic solvent is recovered by a condensing device, the escaped ammonia gas is collected by a tail gas collection device, and finally the sodium tetraphenylborate in the precipitate is collected.

[0066] The method uses the precipitation reaction of sodium tetraphenylborate with ammonia radical ion in aqueous solution as the basic principle, and then selects static separation according to the properties of the precipitate, and the water body can be stored as a carbon source or directly added to the water treatment process as a carbon source. The precipitate collected is dehydrated, and the alkaline solution is heated and recovered, and then can be recycled as a precipitant, and the released concentrated ammonia gas can be collected for industrial production. The method has high reaction efficiency and low interference, high controllability of carbon-nitrogen ratio, main reagents can be recycled, low theoretical operation cost, obvious effect on removing color of sewage, and high industrial value of the discharged carbon source water body.

[0067] Meanwhile, the embodiment also relates to an organic garbage leachate sewage carbonization device for realizing the organic garbage leachate sewage carbonization method, which comprises a uniform feeding device 1, a stirring device 2, a reaction tank 3, an overflow sedimentation tank 4, a buffer tank 5, a dehydration device 6, a membrane filtration system 7 and a storage tank 8.

[0068] The reaction tank 3 serves as the main body of the reaction, and the side wall is provided with a water inlet and a water outlet, and the bottom sedimentation area is provided with a sludge discharge port.

[0069] The overflow sedimentation tank 4 serves as the main body of the secondary precipitation, and the side wall is provided with a water inlet and a water outlet, and the bottom sedimentation area is provided with a sludge discharge port. The uniform feeding device 1 is located above the reaction tank 3 and is provided with a plurality of discharge holes for uniformly adding sodium tetraphenylborate aqueous solution as an ammonia-nitrogen removal agent to the leachate sewage. The stirring device 2 is used for fully stirring and mixing the ammonia-nitrogen removal agent and the leachate sewage in the reaction tank 3. The water inlet of the reaction tank 3 is used for injecting the leachate sewage of the organic garbage, and the water outlet is connected to the water inlet of the overflow sedimentation tank 4. The upper clear liquid preliminarily separated by fully stirring and mixing in the reaction tank 3 is injected into the overflow sedimentation tank 4 for secondary precipitation. The overflow upper clear liquid in the overflow sedimentation tank 4 is sent to the membrane filtration system 7 for membrane filtration through the water outlet, and the membrane-filtered liquid is temporarily stored in the storage tank 8 for use as a carbon source required for adjusting the carbon-nitrogen ratio in the sewage treatment process.

[0070] The lower layer of milky white water-containing precipitate collected at the bottom of the reaction tank 3 and the overflow sedimentation tank 4 is periodically discharged into the dehydration device 6 through the sludge discharge port. The liquid part generated by dehydration is temporarily stored in the storage tank 8 after being filtered by the membrane filtration system 7, and the precipitate generated by dehydration is sent to a heating and condensation recovery device, dissolved in an organic solvent, and added with an excess of strong alkali solution for heating and condensation. The organic solvent is recovered from the condensate, and sodium tetraphenylborate is recovered from the precipitate part left after the organic solvent volatilizes.

[0071] In the embodiment of the present application, the uniform feeding device 1 can uniformly add sodium tetraphenylborate solution from the top through a plurality of holes to prevent local precipitation and difficulty in stirring. Uniform addition is good for controlling the stirring intensity and effect of the solution.

[0072] In the embodiment of the present application, the stirring device 2 can determine the appropriate range of stirring intensity according to different precipitation effects in the project, and the main consideration factor is the tetraphenylboron ammonium polymer precipitation effect. Insufficient stirring can easily lead to poor reaction effect, and too large stirring intensity can easily lead to part of the flocculation floating above the solution, forming high-viscosity substances that are difficult to settle and process. Therefore, the stirring intensity after the reagent is added needs to be controlled, and too strong intensity can lead to part of the flocculation floating to the upper layer of the solution and being difficult to settle.

[0073] In the embodiment of the present application, the reaction tank 3 mainly performs the precipitation reaction of tetraphenylboron sodium and ammonium ions and the polymer precipitation effect of tetraphenylboron sodium, and a precipitation collection funnel is arranged at the bottom to collect the substances polymerized and precipitated in the system.

[0074] In the embodiment of the present application, in the overflow precipitation tank 4, the water body mixed with a large amount of milky white substances enters the precipitation tank from the reaction tank 3 of the device 3, and then is precipitated under the condition of overflow flow. A large-scale precipitation funnel is arranged below to collect the precipitation. In the range of 70 mmol / L to 120 mmol / L of precipitation concentration, the effect is obvious after standing for 5 to 10 hours, the supernatant has little residual precipitation, and the overflow tank is designed according to the precipitation time of 5 to 10 hours. After standing sufficiently, the volume ratio of the supernatant to the precipitation layer is 2:3, and the water outlet is arranged at a position 0.8 times the height of the overflow tank.

[0075] In the embodiment of the present application, the water body after the overflow precipitation of the buffer tank 4 performs a collection and buffering action to prevent the subsequent membrane treatment process from having too large treatment pressure and being difficult to continue running.

[0076] In the embodiment of the present application, the dewatering device 6 adopts a cyclone centrifugal device, which can collect the precipitation water layer in the collection funnel at the bottom of the device 3 and the device 4, perform cyclone treatment, promote solid-liquid separation, further reduce the water content of the precipitation, and return the separated liquid to the device 5 for collection and reprocessing. The solid is collected by centrifugal force, washed and dried, and then subjected to subsequent recovery treatment. Of course, according to the results of the foregoing embodiments, the volume ratio of the solid phase to the liquid phase is between 2:3 and 1:2 under the condition of static stratification, and the dewatering treatment can be completed by centrifugation at a speed of 1000 to 2000 r / min for 20 to 30 min. Therefore, in the project, in addition to the cyclone separator, a plate and frame filter press can also be used, and good dewatering effect can be obtained.

[0077] In the embodiment of the present application, the membrane filtration system 7 is provided with a pore size of 0.45 microns or below, and an ultrafiltration membrane is considered. Experimental determination shows that the minimum particle diameter of the precipitation is greater than 0.45 microns, and there is basically no precipitation residue in the water body after the ultrafiltration membrane.

[0078] In the embodiments of the present application, the storage pool 8 can adopt a pool body or a tank body for collecting water bodies passing through the ultrafiltration membrane for storage as a carbon source.

[0079] The above-described embodiments are only preferred embodiments of the present application, and are not intended to limit the present application. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present application. Therefore, any technical solutions obtained by equivalent replacement or equivalent transformation shall fall within the protection scope of the present application.

Claims

1. A method for carbon source of organic waste leachate sewage, characterized in that, The application relates to an ammonia-nitrogen removal method for leachate sewage of organic garbage. S1, adding an aqueous solution of sodium tetraphenylborate into leachate sewage of organic garbage as an ammonia-nitrogen removal agent, fully stirring and mixing to separate solid and liquid, and obtaining upper clear liquid and lower milky white water-containing precipitate; S2, taking out the lower milky white water-containing precipitate to carry out dehydration treatment, mixing the liquid part generated by dehydration with the upper clear liquid as a carbon source required for adjusting the carbon-nitrogen ratio in a sewage treatment process, dissolving the precipitate generated by dehydration in an organic solvent, adding an excess of a strong alkali solution to carry out heating and condensation, recovering the organic solvent from the condensate, and recovering sodium tetraphenylborate from the precipitate part left after the organic solvent volatilizes.

2. The method of claim 1, wherein the carbon source is added to the organic waste leachate wastewater in an amount of 0.1 to 10 g / L. The adding amount of the ammonia-nitrogen removal agent should be such that the concentration of the precipitate in the mixed system after fully stirring and mixing is between 70 mmol / L and 120 mmol / L. ​ 3. The method for carbon source conversion of organic waste leachate as described in claim 1, characterized in that, The solid-liquid separation is realized by standing for 5-10 hours.

4. The method of claim 1, wherein the carbon source is added to the organic waste leachate wastewater in an amount of 0.1 to 10 g / L. The organic solvent is acetone. ​ 5. The method of claim 1, wherein the carbon source is added to the organic waste leachate wastewater in an amount of 0.1 to 10 g / L. The strong alkali solution is sodium hydroxide aqueous solution. ​ 6. The method of claim 1, wherein the carbon source is added to the organic waste leachate wastewater in an amount of 0.1 to 10 g / L. The precipitate generated by dehydration needs to be cleaned, dried and crushed before being dissolved in the organic solvent.

7. The method of claim 1, wherein the carbon source is added to the organic waste leachate wastewater in an amount of 0.1 to 10 g / L. In the heating and condensation process, the heating temperature is 60-90 DEG C, the heating is carried out until the organic solvent completely volatilizes and leaves the precipitate, the volatilized organic solvent needs to be recovered through a condensing device, the escaped ammonia gas needs to be collected through a tail gas collecting device, and finally the sodium tetraphenylborate in the precipitate is collected.

8. The method of claim 1, wherein the carbon source is added to the organic waste leachate wastewater in an amount of 0.1 to 10 g / L. After the ammonia-nitrogen removal agent is added into the leachate sewage of organic garbage, a flocculant and a coagulant aid need to be further added to strengthen the precipitation.

9. An organic waste leachate wastewater carbon source device, characterized in that, The application further discloses a device for removing ammonia-nitrogen from leachate sewage of organic garbage. The reaction pool (3) is used as the main body of the reaction, the side wall of the reaction pool (3) is provided with a water inlet and a water outlet, and the bottom of the reaction pool (3) is provided with a sludge discharge port; The overflow precipitation pool (4) is used as the main body of the secondary precipitation, the side wall of the overflow precipitation pool (4) is provided with a water inlet and a water outlet, and the bottom of the overflow precipitation pool (4) is provided with a sludge discharge port; The uniform feeding device (1) is located above the reaction pool (3) and is provided with a plurality of discharging holes and is used for uniformly adding the aqueous solution of sodium tetraphenylborate into the leachate sewage as the ammonia-nitrogen removal agent; The stirring device (2) is used for fully stirring and mixing the ammonia-nitrogen removal agent and the leachate sewage in the reaction pool (3); The water inlet of the reaction pool (3) is used for injecting the leachate sewage of organic garbage, the water outlet of the reaction pool (3) is connected with the water inlet of the overflow precipitation pool (4), the upper clear liquid preliminarily separated by fully stirring and mixing in the reaction pool (3) is injected into the overflow precipitation pool (4) to carry out secondary precipitation, the upper clear liquid overflowed from the overflow precipitation pool (4) is sent into the membrane filtration system (7) through the water outlet to carry out membrane filtration, and the liquid after membrane filtration is sent into the storage pool (8) to carry out temporary storage and is used as a carbon source required for adjusting the carbon-nitrogen ratio in a sewage treatment process. The lower layer milky white aqueous precipitate collected at the bottom of the reaction tank (3) and the overflow sedimentation tank (4) is periodically discharged through a sludge discharge port into a dewatering device (6). The liquid portion produced by dewatering is temporarily stored in a storage tank (8) after being filtered through the membrane filtration system (7), while the precipitate produced by dewatering is sent into a heating and condensation recovery device, which recovers the organic solvent by dissolving in the organic solvent and adding an excess of strong alkali solution for heating and condensation, and recovers sodium tetraphenylborate from the precipitate portion left after the organic solvent volatilizes.

10. The organic waste leachate wastewater carbon source device according to claim 9, wherein The dewatering device (6) uses a cyclone separator or a plate and frame filter press.

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