Method and device for preparing microbial denitrification carbon source from brewing wastewater

Abstract

This invention discloses a method and apparatus for preparing a microbial denitrification carbon source from brewing wastewater, belonging to the field of brewing wastewater treatment technology. The method includes: introducing ozone into the brewing wastewater, and carrying out an ozone catalytic oxidation reaction under the action of a catalyst; then adjusting the pH and Mg content of the wastewater. 2+ Content; solid-liquid separation; adding a conditioning agent to the wastewater after solid-liquid separation to obtain a microbial denitrification carbon source. The device disclosed in this invention includes an ozone catalytic conversion system, a solid-liquid separation system, and a conditioning system connected in sequence, and also includes a dosing system for adding chemicals to the above systems respectively; the ozone catalytic conversion system is connected to an ozone generator and a brewing wastewater inlet pipe, and the conditioning system is connected to a wastewater outlet pipe. This invention uses the approach of "ozone catalytic oxidation + denitrification and phosphorus removal + solid-liquid separation + conditioning" to deeply prepare a brewing wastewater-based denitrification carbon source, realizing the resource-based treatment of brewing wastewater and reducing the cost of environmental biological treatment processes.

Description

Technical Field

[0001] This invention belongs to the field of brewing wastewater treatment technology, specifically relating to a method and apparatus for preparing microbial denitrification carbon sources from brewing wastewater. Background Technology

[0002] Brewing wastewater is rich in organic substances such as starch, reducing sugars, acids, alcohols, and esters. It is characterized by numerous impurities, strong odors, and high variability and instability, resulting in high levels of COD, BOD, and SS. Proper treatment of brewing wastewater is necessary to minimize its environmental impact.

[0003] In existing technologies, the core processes for treating brewing wastewater mainly rely on anaerobic biological treatment, aerobic biological treatment, and combinations of both, such as upflow anaerobic sludge blanket (UASB), expanded anaerobic granular sludge blanket (EGSB), integrated flow reactor (IC), sludge batch reactor (SBR), circulating activated sludge process (CASS), biological contact oxidation, and membrane bioreactors. From these brewing wastewater treatment technologies, it can be seen that brewing wastewater is primarily treated as a pollutant, with organic matter in the wastewater forcibly converted into carbon dioxide and water through physicochemical or biodegradation methods. Brewing wastewater originates from the fermentation process of agricultural crops, and no toxic or harmful substances are produced at the source or during the intermediate transformation process, indicating good potential for resource utilization. Its main components include organic acids, small molecule alcohols, amino acids, peptides, phenolic substances, and alkaloids; therefore, research on the resource utilization of brewing wastewater is gradually expanding. Examples include bio-hydrogen production, methanogenesis, and fuel cells. However, due to the need for optimized design in terms of operation and maintenance, operating costs, and economic value, there is still a long way to go in terms of practical application and promotion.

[0004] Given that brewing wastewater is readily utilized by microorganisms, using it as a carbon source for microbial denitrification is a highly effective treatment approach. Investigations have shown that municipal wastewater is often treated using activated sludge processes such as AAO and SBR, but due to the low C / N ratio (3-4), insufficient carbon source is frequently encountered during denitrification. Traditional solutions involve adding sodium acetate, methanol, or glucose as external carbon sources to ensure efficient nitrogen and phosphorus removal, but this increases the economic burden on wastewater treatment plants. Therefore, in recent years, brewing wastewater has been increasingly used as a carbon source in municipal wastewater treatment research. These alternative carbon sources improve the nitrogen and phosphorus removal efficiency of AAO, SBR, and denitrification processes, and offer advantages such as high utilization rates, no byproducts, and no adverse effects on the water treatment system.

[0005] Therefore, providing a method for preparing microbial denitrification carbon sources using brewing wastewater as raw material, in order to realize the resource utilization of brewing bottom water, solve the problem of wastewater treatment and disposal that plagues the liquor industry, and explore a practical and feasible resource utilization path for high-concentration organic wastewater, has become an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0006] One of the objectives of this invention is to provide a method for preparing microbial denitrification carbon sources from brewing wastewater. This method uses the approach of "ozone catalytic oxidation + nitrogen and phosphorus removal + solid-liquid separation + blending" to deeply prepare brewing bottom pot water-based denitrification carbon sources. The method is simple and easy to operate, which not only realizes the resource-based treatment of bottom pot water, but also reduces the cost of environmental biological treatment processes, and has good application value and prospects.

[0007] The second objective of this invention is to provide an apparatus for preparing a microbial denitrification carbon source from brewing wastewater using the above-described method.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0009] This invention discloses a method for preparing microbial denitrification carbon sources from brewing wastewater, comprising the following steps:

[0010] Step 1. Introduce ozone into the brewing wastewater to carry out an ozone catalytic oxidation reaction under the action of a catalyst;

[0011] Step 2. Nitrogen and phosphorus removal: Control the pH and Mg content of the wastewater after the ozone catalytic oxidation reaction. 2+ To determine the content of nitrogen and phosphorus in wastewater;

[0012] Step 3. Solid-liquid separation: The wastewater treated in Steps 1 and 2 is subjected to solid-liquid separation;

[0013] Step 4. Blending: Add a blending agent to the wastewater after solid-liquid separation to obtain a microbial denitrification carbon source.

[0014] In some embodiments of the present invention, in step 1, the pH value of the brewing wastewater is controlled to be 3-5, and the ozone content is controlled to be 5-10 g / m³. 3 The hydraulic retention time is 1-3 hours, preferably 2 hours;

[0015] Preferably, the catalyst is a heterogeneous catalyst, more preferably an iron-based catalyst; even more preferably, the catalyst loading is 0.25-0.5.

[0016] Preferably, a defoamer is added in step 1; more preferably, the amount of defoamer added is 5-10 wt.‰ of the brewing wastewater.

[0017] Or / and in step 2, add alkaline solution and magnesium salt to the wastewater after the ozone catalytic oxidation reaction, adjust the pH value to 8-9, and react for 10-60 min, preferably 30 min;

[0018] Preferably, the magnesium salt is a water-soluble magnesium salt, more preferably magnesium sulfate;

[0019] Preferably, in the wastewater after adding magnesium salts, Mg 2+ With PO4 3- The molar ratio is 1.0 to 1.3:1.

[0020] Or / and in step 3, a membrane module is used for solid-liquid separation.

[0021] Preferably, the effluent from the membrane module is sent to step 4 for the preparation of a microbial denitrification carbon source;

[0022] Preferably, the concentrate from the membrane module is dehydrated by pressure filtration, the liquid phase is returned to step 2, and the solid phase is transported off-site for disposal.

[0023] Or / and the conditioning agent in step 4 includes zinc sulfate: 0.1-0.2 wt.‰; ferrous chloride: 0.05-0.1 wt.‰; sodium molybdate: 0.2-0.4 wt.‰; copper chloride: 0.05-0.1 wt.‰; the amount of conditioning agent added is 0.5-1 wt.‰ of the mass of the wastewater after solid-liquid separation.

[0024] In some embodiments of the present invention, the brewing wastewater is brewing bottom water or yellow water.

[0025] The present invention discloses an apparatus for preparing microbial denitrification carbon source from brewing wastewater. The apparatus adopts the above-mentioned method and includes an ozone catalytic conversion system, a solid-liquid separation system and a blending system connected in sequence. It also includes a dosing system for adding chemicals to the ozone catalytic conversion system, the solid-liquid separation system and the blending system respectively.

[0026] The ozone catalytic conversion system is connected to an ozone generator and a brewing wastewater input pipe, while the blending system is connected to a wastewater output pipe.

[0027] In some embodiments of the present invention, the ozone catalytic conversion system includes an ozone catalytic unit and a nitrogen and phosphorus removal unit; wherein the ozone catalytic unit includes an ozone reactor and a gas distributor located at the bottom of the ozone reactor, and the nitrogen and phosphorus removal unit includes a nitrogen and phosphorus removal reactor; preferably, the nitrogen and phosphorus removal reactor is provided with a first stirrer;

[0028] Preferably, the ozone generator is connected to the gas distributor via a pipeline, which is used to send the ozone generated by the ozone generator into the gas distributor via the pipeline, and then into the brewing wastewater of the ozone reactor through the gas distributor.

[0029] Preferably, the ozone reactor is provided with an overflow port at the top, which is connected to the denitrification and phosphorus removal reactor via a pipeline, for overflowing the wastewater in the ozone reactor into the denitrification and phosphorus removal reactor.

[0030] In some embodiments of the present invention, the solid-liquid separation system includes a tubular filter membrane;

[0031] Preferably, the inlet of the tubular filter membrane is connected to the denitrification and phosphorus removal reactor via a denitrification and phosphorus removal liquid conveying pipe, and the outlet of the tubular filter membrane is connected to the blending system to send the filtered effluent into the blending system.

[0032] Preferably, the concentrate outlet of the tubular ultrafiltration membrane is connected to a filter press; the outlet of the filter press is connected to a denitrification and phosphorus removal reactor via a pipeline, which is used to return the filtered liquid phase for further denitrification and phosphorus removal.

[0033] In some embodiments of the present invention, the mixing system includes a mixing tank; preferably, the mixing tank is provided with a second stirrer;

[0034] The mixing tank is connected to the outlet of the tubular filter membrane via a filter outlet pipe. The mixing tank is also connected to a wastewater output pipe, which is used to send the mixed wastewater as a carbon source to the wastewater treatment plant.

[0035] In some embodiments of the present invention, the dosing system includes an antifoaming agent storage tank, an alkali storage tank, and a formulation agent storage tank; the antifoaming agent storage tank is connected to the ozone reactor via an antifoaming agent delivery pipe, the alkali storage tank is connected to the denitrification and phosphorus removal reactor via an alkali delivery pipe, and the formulation agent storage tank is connected to the formulation tank via a formulation agent delivery pipe.

[0036] In some embodiments of the present invention, metering pumps are installed on the defoamer delivery pipe, the alkali delivery pipe, and the formulation delivery pipe.

[0037] In some embodiments of the present invention, a first pump is provided on the denitrification and phosphorus removal liquid conveying pipe, and a circulation pump is provided on the denitrification and phosphorus removal liquid conveying pipe between the first pump and the inlet of the tubular filter membrane. The concentrated liquid outlet of the tubular filter membrane is connected to the circulation pump via a pipeline.

[0038] Preferably, a second pump is installed on the filtered water outlet pipe, and a third pump is installed on the sewage output pipe.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] This invention fully considers the current status of water treatment in brewing enterprises, takes brewing wastewater as the research object, and adopts the scheme of "ozone catalytic oxidation + denitrification and phosphorus removal + solid-liquid separation + blending" to deeply prepare brewing wastewater-based denitrifying carbon source. The brewing wastewater-based denitrifying carbon source obtained by the method of this invention not only realizes the resource-based treatment of brewing wastewater, but also reduces the cost of environmental biological treatment process, and has good application value and prospects. It solves the problem of wastewater treatment and disposal that plagues the liquor industry, and greatly improves the ecological, environmental and economic benefits of brewing enterprises. Attached Figure Description

[0041] Appendix Figure 1 This is a schematic diagram of the device structure of the present invention.

[0042] Appendix Figure 2 This is a comparison diagram showing the effect of the carbon source prepared in this invention on conventional carbon sources during the denitrification process.

[0043] The names corresponding to the reference numerals in the attached figures are:

[0044] 1-Ozone catalytic conversion system, 11-Ozone reactor, 12-Denitrification and phosphorus removal reactor, 13-First stirrer, 14-Ozone generator, 15-Gas distributor, 16-Brewing wastewater inlet pipe;

[0045] 2-Solid-liquid separation system, 21-Denitrification and phosphorus removal liquid delivery pipe, 22-Filtered water outlet pipe, 23-First pump, 24-Circulation pump, 25-Second pump;

[0046] 3-Blending system, 31-Blending tank, 32-Second agitator, 33-Sewage output pipe, 34-Third pump;

[0047] 4-Dosing system, 41-Defoamer storage tank, 42-Alkali storage tank, 43-Formulin storage tank, 4-Defoamer delivery pipe, 45-Alkali delivery pipe, 46-Formulin delivery pipe;

[0048] 5-Filter press. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0050] A method for preparing a microbial denitrification carbon source from brewing wastewater includes the following steps:

[0051] Step 1. Introduce ozone into the brewing wastewater to carry out an ozone catalytic oxidation reaction under the action of a catalyst;

[0052] Step 2. Nitrogen and phosphorus removal: Control the pH and Mg content of the wastewater after the ozone catalytic oxidation reaction. 2+ To determine the content of nitrogen and phosphorus in wastewater;

[0053] Step 3. Solid-liquid separation: The wastewater treated in Steps 1 and 2 is subjected to solid-liquid separation;

[0054] Step 4. Blending: Add a blending agent to the wastewater after solid-liquid separation to obtain a microbial denitrification carbon source.

[0055] In step 1, the pH of the brewing wastewater is controlled to be 3-5, and the ozone concentration is controlled to be 5-10 g / m³. 3 The hydraulic retention time is 1-3 hours, preferably 2 hours; preferably, the catalyst is a heterogeneous catalyst, more preferably an iron-based catalyst; more preferably, the catalyst loading is 0.25-0.5; preferably, an antifoaming agent is added in step 1, more preferably, the amount of antifoaming agent added is 5-10 wt.‰ of the brewing wastewater.

[0056] Since the pH of the brewing pot water is 3.5-5, no additional adjustment is needed for this catalytic process. The ozone concentration is controlled at 5-10 g / L, the defoamer dosage is 5-10‰, the catalyst loading is between 0.25-0.5 g / L, the reaction temperature is room temperature, and the reaction time is 2.5 hours. The catalyst loading amount mentioned in this invention refers to the volume of wastewater in the reactor. For example, if the volume of brewing wastewater in the ozone reactor is 1 L and the catalyst is 0.25 L, then the catalyst loading amount is 0.25 L.

[0057] The COD in the brewing pot water was reduced by 20% (determination of chemical oxygen demand in water by rapid digestion spectrophotometry (HJ / T399-2007)). Macromolecules and easily oxidized substances reacted with oxides in the system to transform into stable organic substances, thus enhancing the stability of the brewing pot water.

[0058] In step 2, an alkaline solution is added to the wastewater after the controlled ozone catalytic oxidation reaction to adjust the pH to 8-9, and the reaction is carried out for 10-60 minutes, preferably 30 minutes; preferably, the wastewater after adding magnesium salt contains Mg 2+ With PO4 3- The molar ratio is 1.0 to 1.3:1. Preferably, the magnesium salt is a water-soluble magnesium salt, more preferably magnesium sulfate.

[0059] Since the brewing batch water is a product of grain fermentation, it contains ammonia nitrogen and phosphorus compounds, which is detrimental to the subsequent utilization of carbon sources and increases the load on ammonia nitrogen and total phosphorus treatment during practical applications. Therefore, it is essential to carry out necessary nitrogen and phosphorus removal. This invention, taking into account the water quality characteristics of the brewing batch water, utilizes magnesium ammonium phosphate precipitation to simultaneously remove ammonia nitrogen and total phosphorus.

[0060] Since the brewing pot water contains magnesium salts, ammonia nitrogen, and phosphorus, this provides a prerequisite for simultaneous nitrogen and phosphorus removal. This invention addresses this by controlling pH and appropriately controlling Mg... 2+ The removal of nitrogen and phosphorus from the brewing pot water, under conditions of sufficient reaction time, is a crucial step in the preparation of a high-quality carbon source. The basic principle is as follows:

[0061] Mg 2+ +PO4 3- +NH4 + +6H₂O→MgNH₄PO₄·6H₂O

[0062] Mg 2+ The addition amount is 1.0-1.3 times the phosphorus molar content in the bottom pot water, the pH is controlled between 8.0 and 9.0, the reaction time is 0.5h, the ammonia nitrogen removal rate can be maintained above 60% (determination of ammonia nitrogen in water quality by Nessler's reagent spectrophotometric method (HJ 535-2009)), and the total phosphorus removal rate can be maintained above 80% (determination of total phosphorus in water quality by ammonium molybdate spectrophotometric method (GB 11893-89)), which greatly ensures the subsequent use of carbon source and prevents the impact of nitrogen and phosphorus on the water treatment process of the user unit.

[0063] In step 3, a membrane module is used for solid-liquid separation; preferably, the effluent from the membrane module is sent to step 4 for the preparation of a microbial denitrification carbon source; preferably, the concentrate from the membrane module is dehydrated by pressure filtration, with the liquid phase returned to step 2 and the solid phase disposed of off-site.

[0064] After ozone catalytic oxidation and denitrification / phosphorus removal processes, phosphate and magnesium ammonium phosphate precipitates are generated in the brewing batch water. To prevent these precipitates from affecting the subsequent use of carbon sources, necessary treatment of the brewing batch water is essential. This invention employs high-efficiency ultrafiltration membrane separation technology to achieve solid-liquid separation, removing phosphate and magnesium ammonium phosphate precipitates, as well as large molecular substances from the water.

[0065] In one embodiment of the present invention, the ultrafiltration membrane is made of hydrophilic PVDF material, the membrane tube diameter is 8 mm, the operating pressure is below 6 bar, the operating temperature is room temperature, and the water flux is 100 L / m³. 2 After the brewing pot water is separated by ultrafiltration membrane, the suspended solids removal rate is close to 100% (determination of suspended solids in water quality by gravimetric method (GB 11901-89)), which greatly reduces the treatment load of subsequent processes.

[0066] The conditioning agent in step 4 includes organic acid, zinc salt, iron salt, molybdenum salt, and copper salt. The amount of conditioning agent added is 0.5-1 wt.‰ of the mass of the wastewater after solid-liquid separation.

[0067] To reduce the impact of carbon source addition on the denitrification process, this invention utilizes organic acids such as acetic acid and formic acid to adjust the pH of the prepared carbon source to approximately neutral. These organic acids can be rapidly utilized by microorganisms and have no significant impact on them. Based on the pH characteristics of brewing wastewater, the addition amount is controlled at 0.5-1 wt.%.

[0068] This invention discloses an apparatus for preparing microbial denitrification carbon source from brewing wastewater. The apparatus adopts the method described in any one of claims 1-3. The apparatus includes an ozone catalytic conversion system 1, a solid-liquid separation system 2, and a blending system 3 connected in sequence. It also includes a dosing system 4 for adding chemicals to the ozone catalytic conversion system 1, the solid-liquid separation system 2, and the blending system 3 respectively.

[0069] The ozone catalytic conversion system 1 is connected to an ozone generator 14 and a brewing wastewater input pipe 16, and the blending system 3 is connected to a sewage output pipe 33.

[0070] The ozone catalytic conversion system 1 includes an ozone catalytic unit and a nitrogen and phosphorus removal unit; wherein the ozone catalytic unit includes an ozone reactor 11 and a gas distributor 15 located at the bottom of the ozone reactor 11, and the nitrogen and phosphorus removal unit includes a nitrogen and phosphorus removal reactor 12; preferably, the nitrogen and phosphorus removal reactor 12 is provided with a first stirrer 13.

[0071] Preferably, the ozone generator 14 is connected to the gas distributor 15 via a pipe, which is used to send the ozone generated by the ozone generator 14 into the gas distributor 15 via the pipe, and then into the brewing wastewater of the ozone reactor 11 via the gas distributor 15.

[0072] Preferably, the ozone reactor 11 is provided with an overflow port at the top, and the overflow port is connected to the denitrification and phosphorus removal reactor 12 via a pipe, for overflowing the wastewater in the ozone reactor 11 into the denitrification and phosphorus removal reactor 12.

[0073] The solid-liquid separation system 2 includes a tubular filter membrane;

[0074] Preferably, the inlet of the tubular filter membrane is connected to the denitrification and phosphorus removal reactor 12 via the denitrification and phosphorus removal liquid conveying pipe 21, and the outlet of the tubular filter membrane is connected to the blending system 3 for sending the filtered effluent into the blending system 3.

[0075] Preferably, the concentrated liquid outlet of the tubular ultrafiltration membrane is connected to a filter press 5; the outlet of the filter press 5 is connected to the denitrification and phosphorus removal reactor 12 via a pipeline, for returning the filtered liquid phase for further denitrification and phosphorus removal.

[0076] The mixing system 3 includes a mixing tank 31; preferably, the mixing tank 31 is provided with a second stirrer 32;

[0077] The mixing tank 31 is connected to the outlet of the tubular filter membrane via a filter outlet pipe 22. The mixing tank 31 is also connected to a sewage output pipe 33, which is used to send the mixed sewage as a carbon source to the sewage treatment plant.

[0078] The dosing system 4 includes an antifoaming agent storage tank 41, an alkali solution storage tank 42, and a formulation agent storage tank 43; the antifoaming agent storage tank 41 is connected to the ozone reactor 11 via an antifoaming agent delivery pipe 44, the alkali solution storage tank 42 is connected to the denitrification and phosphorus removal reactor 12 via an alkali solution delivery pipe 45, and the formulation agent storage tank 43 is connected to the formulation tank 31 via a formulation agent delivery pipe 46.

[0079] Metering pumps are installed on the defoamer delivery pipe 44, the alkali delivery pipe 45, and the conditioning agent delivery pipe 46.

[0080] A first pump 23 is installed on the denitrification and phosphorus removal liquid delivery pipe 21. A circulation pump 24 is installed on the denitrification and phosphorus removal liquid delivery pipe 21 between the first pump 23 and the inlet of the tubular filter membrane. The concentrated liquid outlet of the tubular filter membrane is connected to the circulation pump 24 via a pipeline.

[0081] Preferably, a second pump 25 is installed on the filtered water outlet pipe 22, and a third pump 34 is installed on the sewage output pipe 33.

[0082] Example 1

[0083] As attached Figure 1 As shown, this embodiment discloses an apparatus for preparing microbial denitrification carbon source from brewing wastewater according to the present invention, including an ozone catalytic conversion system 1, a solid-liquid separation system 2 and a blending system 3 connected in sequence, and a dosing system 4 for adding chemicals to the ozone catalytic conversion system 1, the solid-liquid separation system 2 and the blending system 3 respectively;

[0084] The ozone catalytic conversion system 1 includes an ozone catalytic unit and a nitrogen and phosphorus removal unit; wherein the ozone catalytic unit includes an ozone reactor 11 and a gas distributor 15 located at the bottom of the ozone reactor 11, and the nitrogen and phosphorus removal unit includes a nitrogen and phosphorus removal reactor 12 equipped with a first stirrer 13.

[0085] The ozone reactor 11 is connected to an ozone generator 14 and a brewing wastewater inlet pipe 16. The ozone generator 14 is connected to a gas distributor 15 via a pipe, which is used to send the ozone generated by the ozone generator 14 into the gas distributor 15 via the pipe, and then into the brewing wastewater of the ozone reactor 11 via the gas distributor 15.

[0086] An overflow port is provided at the top of the ozone reactor 11. The overflow port is connected to the denitrification and phosphorus removal reactor 12 via a pipe, and is used to overflow the wastewater in the ozone reactor 11 into the denitrification and phosphorus removal reactor 12.

[0087] The solid-liquid separation system 2 includes a tubular filter membrane; the inlet of the tubular filter membrane is connected to the denitrification and phosphorus removal reactor 12 via the denitrification and phosphorus removal liquid conveying pipe 21, and the outlet of the tubular filter membrane is connected to the blending system 3 for sending the filtered effluent into the blending system 3.

[0088] The concentrated liquid outlet of the tubular ultrafiltration membrane is connected to a filter press 5; the outlet of the filter press 5 is connected to the denitrification and phosphorus removal reactor 12 via a pipeline, which is used to return the filtered liquid phase for denitrification and phosphorus removal again.

[0089] The mixing system 3 includes a mixing tank 31 equipped with a second stirrer 32; the mixing tank 31 is connected to the outlet of the tubular filter membrane via a filter outlet pipe 22, and the mixing tank 31 is connected to a sewage output pipe 33 for sending the mixed sewage as a carbon source to the sewage treatment plant.

[0090] The dosing system 4 includes an antifoaming agent storage tank 41, an alkali solution storage tank 42, and a formulation agent storage tank 43; the antifoaming agent storage tank 41 is connected to the ozone reactor 11 via an antifoaming agent delivery pipe 44, the alkali solution storage tank 42 is connected to the denitrification and phosphorus removal reactor 12 via an alkali solution delivery pipe 45, and the formulation agent storage tank 43 is connected to the formulation tank 31 via a formulation agent delivery pipe 46.

[0091] Metering pumps are installed on the defoamer delivery pipe 44, the alkali delivery pipe 45, and the conditioning agent delivery pipe 46.

[0092] A first pump 23 is installed on the denitrification and phosphorus removal liquid delivery pipe 21. A circulation pump 24 is installed on the denitrification and phosphorus removal liquid delivery pipe 21 between the first pump 23 and the inlet of the tubular filter membrane. The concentrated liquid outlet of the tubular filter membrane is connected to the circulation pump 24 via a pipeline.

[0093] A second pump 25 is installed on the filtered water outlet pipe 22, and a third pump 34 is installed on the sewage output pipe 33.

[0094] Example 2

[0095] This embodiment discloses a method for preparing microbial denitrification carbon source from brewing wastewater using the apparatus of Embodiment 1. The brewing wastewater in this embodiment is brewing bottom water.

[0096] Specifically, the steps include the following:

[0097] Step 1. The brewing wastewater is fed into the ozone reactor, and defoamer and catalyst are added to the brewing wastewater. The ozone generated by the ozone generator is introduced into the brewing wastewater in the ozone reactor through the gas distributor to carry out the ozone catalytic oxidation reaction.

[0098] The pH value of the brewing pot water in this embodiment is 3.5-5, so no additional adjustment is required for this catalytic process;

[0099] The catalyst in this embodiment is a heterogeneous catalyst, ferric oxide, with a loading of 0.25.

[0100] The ozone concentration in the reaction system was controlled at 10 g / L, the amount of defoamer added was 5 wt.‰, the reaction was carried out at room temperature, and the hydraulic retention time was 2.5 h.

[0101] In this step, the COD in the brewing pot water is reduced by 20% through ozone catalytic oxidation (determination of chemical oxygen demand in water by rapid digestion spectrophotometry (HJ / T 399-2007)). Macromolecules and easily oxidized substances react with the oxides in the system to transform into stable organic substances, thereby enhancing the stability of the brewing pot water.

[0102] Step 2. Denitrification and Phosphorus Removal: The brewing wastewater after the ozone catalytic oxidation reaction in Step 1 flows by gravity into the denitrification and phosphorus removal reactor. The pH of the wastewater after the ozone catalytic oxidation reaction is controlled to 8.0-9.0 by adding alkaline solution (sodium hydroxide aqueous solution). Magnesium sulfate and Mg sulfate are also added to the wastewater after the ozone catalytic oxidation reaction. 2+ The amount added is 1.0 times the phosphorus molar content in the bottom pot water, and the reaction is carried out at room temperature for 0.5 hours to remove nitrogen and phosphorus from the wastewater.

[0103] Step 2 ensures that the ammonia nitrogen removal rate can be maintained above 60% (Determination of ammonia nitrogen in water quality by Nessler's reagent spectrophotometric method (HJ 535-2009)) and the total phosphorus removal rate can be maintained above 80% (Determination of total phosphorus in water quality by ammonium molybdate spectrophotometric method (GB11893-89)), which greatly guarantees the subsequent use of carbon sources and prevents nitrogen and phosphorus from impacting the water treatment process of the user unit.

[0104] Step 3. Solid-liquid separation: The wastewater treated in Steps 1 and 2 is subjected to solid-liquid separation using a tubular ultrafiltration membrane; the effluent from the tubular ultrafiltration membrane is sent to Step 4 for the preparation of a carbon source for microbial denitrification; the concentrate from the tubular ultrafiltration membrane is dehydrated by pressure filtration, with the liquid phase returned to Step 2 and the solid phase transported for disposal.

[0105] In this embodiment, the ultrafiltration membrane is made of hydrophilic PVDF material, with a membrane tube diameter of 8 mm, an operating pressure below 6 bar, an operating temperature of room temperature, and a water flux of 100 L / m³. 2 After the brewing pot water is separated by ultrafiltration membrane, the suspended solids removal rate is close to 100% (determination of suspended solids in water quality by gravimetric method (GB 11901-89)), which greatly reduces the treatment load of subsequent processes.

[0106] Step 4. Preparation: A conditioning agent is added to the wastewater after solid-liquid separation to prepare a carbon source for microbial denitrification. The conditioning agent contains zinc sulfate (0.2 wt.‰), ferrous chloride (0.1 wt.‰), sodium molybdate (0.4 wt.‰), and copper chloride (0.1 wt.‰); the amount of conditioning agent added is 0.5 wt.‰ of the mass of the wastewater after solid-liquid separation. The pH of the prepared carbon source is adjusted to approximately neutral using organic acids.

[0107] Example 3

[0108] This embodiment differs from Embodiment 2 in that it uses different brewing wastewater, but all other conditions remain the same. The brewing wastewater in this embodiment is yellow water.

[0109] Example 4

[0110] This embodiment differs from Embodiment 2 in that the parameters are different, but all other conditions are the same. The steps of this embodiment are as follows:

[0111] Step 1. The brewing wastewater is fed into the ozone reactor, and defoamer and catalyst are added to the brewing wastewater. The ozone generated by the ozone generator is introduced into the brewing wastewater in the ozone reactor through the gas distributor to carry out the ozone catalytic oxidation reaction.

[0112] The pH value of the brewing pot water in this embodiment is 3.5-5, so no additional adjustment is required for this catalytic process;

[0113] The catalyst in this embodiment is a heterogeneous catalyst, ferric oxide, with a loading amount of 0.5.

[0114] The ozone concentration in the reaction system was controlled at 5 g / L, the amount of defoamer added was 10 wt.‰, the reaction was carried out at room temperature, and the hydraulic retention time was 3 h.

[0115] The COD in the brewing pot water is reduced by 20% through the ozone catalytic oxidation reaction in step 1.

[0116] Step 2. Denitrification and Phosphorus Removal: The brewing wastewater after the ozone catalytic oxidation reaction in Step 1 flows by gravity into the denitrification and phosphorus removal reactor. The pH of the wastewater after the ozone catalytic oxidation reaction is controlled to 8.0-9.0 by adding alkaline solution (sodium hydroxide aqueous solution). Magnesium sulfate and Mg sulfate are also added to the wastewater after the ozone catalytic oxidation reaction. 2+ The amount added is 1.3 times the phosphorus molar content in the bottom pot water, and the reaction is carried out at room temperature for 1 hour to remove nitrogen and phosphorus from the wastewater.

[0117] Through step 2, the ammonia nitrogen removal rate can be maintained above 60%, and the total phosphorus removal rate can be maintained above 80%.

[0118] Step 3. Solid-liquid separation: The wastewater treated in Steps 1 and 2 is subjected to solid-liquid separation using a tubular ultrafiltration membrane; the effluent from the tubular ultrafiltration membrane is sent to Step 4 for the preparation of a carbon source for microbial denitrification; the concentrate from the tubular ultrafiltration membrane is dehydrated by pressure filtration, with the liquid phase returned to Step 2 and the solid phase transported for disposal.

[0119] In this embodiment, the ultrafiltration membrane is made of hydrophilic PVDF material, with a membrane tube diameter of 8 mm, an operating pressure below 6 bar, an operating temperature of room temperature, and a water flux of 100 L / m³. 2 After the brewing pot water is separated by ultrafiltration membrane, the suspended solids removal rate is close to 100% (determination of suspended solids in water quality by gravimetric method (GB 11901-89)), which greatly reduces the treatment load of subsequent processes.

[0120] Step 4. Preparation: A conditioning agent is added to the wastewater after solid-liquid separation to prepare a carbon source for microbial denitrification. The conditioning agent contains zinc sulfate: 0.1 wt.‰, ferrous chloride: 0.05 wt.‰, sodium molybdate: 0.2 wt.‰, and copper chloride: 0.05 wt.‰; the amount of conditioning agent added is 1 wt.‰ of the mass of the wastewater after solid-liquid separation. The pH of the prepared carbon source is adjusted to approximately neutral using organic acids.

[0121] Example 5

[0122] This embodiment differs from Embodiment 2 in that the parameters are different, but all other conditions are the same. The steps of this embodiment are as follows:

[0123] Step 1. The brewing wastewater is fed into the ozone reactor, and defoamer and catalyst are added to the brewing wastewater. The ozone generated by the ozone generator is introduced into the brewing wastewater in the ozone reactor through the gas distributor to carry out the ozone catalytic oxidation reaction.

[0124] The pH value of the brewing pot water in this embodiment is 3.5-5, so no additional adjustment is required for this catalytic process;

[0125] The catalyst in this embodiment is a heterogeneous catalyst, ferric oxide, with a loading amount of 0.5.

[0126] The ozone concentration in the reaction system was controlled at 7.5 g / L, the defoamer dosage was 8 wt.‰, the reaction was carried out at room temperature, and the hydraulic retention time was 1 h.

[0127] Step 2. Denitrification and Phosphorus Removal: The brewing wastewater after the ozone catalytic oxidation reaction in Step 1 flows by gravity into the denitrification and phosphorus removal reactor. The pH of the wastewater after the ozone catalytic oxidation reaction is controlled to 8.0-9.0 by adding alkaline solution (sodium hydroxide aqueous solution). Magnesium sulfate and Mg sulfate are also added to the wastewater after the ozone catalytic oxidation reaction. 2+ The amount added is 1.2 times the phosphorus molar content in the bottom pot water, and the reaction is carried out at room temperature for 20 minutes to remove nitrogen and phosphorus from the wastewater.

[0128] Through step 2, the ammonia nitrogen removal rate can be maintained above 60%, and the total phosphorus removal rate can be maintained above 80%.

[0129] Step 3. Solid-liquid separation: The wastewater treated in Steps 1 and 2 is subjected to solid-liquid separation using a tubular ultrafiltration membrane; the effluent from the tubular ultrafiltration membrane is sent to Step 4 for the preparation of a carbon source for microbial denitrification; the concentrate from the tubular ultrafiltration membrane is dehydrated by pressure filtration, with the liquid phase returned to Step 2 and the solid phase transported for disposal.

[0130] In this embodiment, the ultrafiltration membrane is made of hydrophilic PVDF material, with a membrane tube diameter of 8 mm, an operating pressure below 6 bar, an operating temperature of room temperature, and a water flux of 100 L / m³. 2 After the brewing pot water is separated by ultrafiltration membrane, the suspended solids removal rate is close to 100% (determination of suspended solids in water quality by gravimetric method (GB 11901-89)), which greatly reduces the treatment load of subsequent processes.

[0131] Step 4. Preparation: A conditioning agent is added to the wastewater after solid-liquid separation to prepare a carbon source for microbial denitrification. The conditioning agent contains zinc sulfate (0.2 wt.‰), ferrous chloride (0.05 wt.‰), sodium molybdate (0.3 wt.‰), and copper chloride (0.07 wt.‰); the amount of conditioning agent added is 0.8 wt.‰ of the mass of the wastewater after solid-liquid separation. The pH of the prepared carbon source is adjusted to approximately neutral using organic acids.

[0132] Experimental Example 1

[0133] In this experiment, carbon sources prepared from brewing wastewater treated in Examples 2 and 3 were used as carbon sources for microbial denitrification, and sodium acetate, glucose, and sucrose were used as controls to investigate the effects of different carbon sources on the efficiency of microbial denitrification.

[0134] The specific steps are as follows:

[0135] 1. Prepare simulated nitrogen-containing wastewater using sodium nitrate and tap water, with a total nitrogen concentration of approximately 120 ppm and a pH of 6-7.5;

[0136] 2. Select a 2L denitrifier, add 2L of nitrogen-containing wastewater, then add 400ppm of carbon source (calculated as COD), followed by 100ppm of denitrifying bacteria, mix well and seal, and place in the dark for denitrification reaction;

[0137] 3. During the denitrification process, samples were taken at 12h, 24h, 36h, 60h and 72h of reaction for determination of total nitrogen (see "Determination of Total Nitrogen in Water by Alkaline Potassium Persulfate Digestion Ultraviolet Spectrophotometry (HJ 636—2012)").

[0138] The results are attached. Figure 2 As shown.

[0139] The results above show that, as the denitrification reaction proceeds, the carbon source prepared from brewing bottom water and yellow water can reduce total nitrogen from 120 ppm to about 15 ppm, maintaining a denitrification rate of about 87.5%, demonstrating a denitrification effect comparable to conventional carbon sources such as sodium acetate, glucose, and sucrose. Furthermore, the carbon source prepared from brewing bottom water and yellow water exhibits a faster degradation rate in the first 36 hours, especially the carbon source prepared from yellow water, which reduces total nitrogen from 120 ppm to about 20 ppm within 24 hours, fully demonstrating the significant advantages of carbon sources prepared from brewing bottom water and yellow water in the denitrification process.

[0140] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing microbial denitrification carbon source from brewing wastewater, characterized in that, The brewing wastewater is the bottom water or yellow water from the brewing process, and the method includes the following steps: Step 1. Introduce ozone into the brewing wastewater to carry out an ozone catalytic oxidation reaction under the action of a catalyst; Step 2. Nitrogen and phosphorus removal: Control the pH and Mg content of the wastewater after the ozone catalytic oxidation reaction. 2+ To determine the content of nitrogen and phosphorus in wastewater; Step 3. Solid-liquid separation: The wastewater treated in Steps 1 and 2 is subjected to solid-liquid separation; Step 4. Blending: Add a blending agent to the wastewater after solid-liquid separation to obtain a carbon source for microbial denitrification; In step 1, the pH of the brewing wastewater is controlled to be 3-5, and the ozone concentration is controlled to be 5-10 g / m³. 3 The hydraulic retention time is 1-3 hours, and the catalyst is an iron-based catalyst. In step 2, an alkaline solution and water-soluble magnesium salt are added to the wastewater after the ozone catalytic oxidation reaction to adjust the pH to 8-9, and the reaction is carried out for 10-60 minutes; in the wastewater after adding magnesium salt, Mg 2+ With PO4 3- The molar ratio is 1.0~1.3:1; In step 3, a membrane module is used for solid-liquid separation. The effluent from the membrane module is sent to step 4 to prepare a carbon source for microbial denitrification. The concentrate from the membrane module is dehydrated by pressure filtration. The liquid phase is returned to step 2, and the solid phase is transported for disposal. The preparation agent in step 4 includes zinc sulfate: 0.1-0.2 wt.‰; Ferrous chloride: 0.05-0.1 wt.‰; Sodium molybdate: 0.2-0.4 wt.‰; Copper chloride: 0.05-0.1 wt.‰; the amount of conditioning agent added is 0.5-1 wt.‰ of the mass of the wastewater after solid-liquid separation.

2. The method according to claim 1, characterized in that, In step 1, the hydraulic residence time is 2 hours.

3. The method according to claim 1, characterized in that, In step 1, the catalyst loading amount is 0.25-0.

5.

4. The method according to claim 1, characterized in that, In step 1, an antifoaming agent is added, and the amount added is 5-10 wt.‰ of the brewing wastewater.

5. The method according to claim 1, characterized in that, In step 2, the reaction time is 30 minutes.

6. The method according to claim 1, characterized in that, The magnesium salt is magnesium sulfate.

7. An apparatus for preparing a microbial denitrification carbon source from brewing wastewater, characterized in that, The device employs the method described in any one of claims 1-6. The device comprises an ozone catalytic conversion system (1), a solid-liquid separation system (2), and a blending system (3) connected in sequence. It also includes a dosing system (4) for adding chemicals to the ozone catalytic conversion system (1), the solid-liquid separation system (2), and the blending system (3) respectively. The ozone catalytic conversion system (1) is connected to an ozone generator (14) and a brewing wastewater input pipe (16), and the blending system (3) is connected to a sewage output pipe (33). The ozone catalytic conversion system (1) includes an ozone catalytic unit and a nitrogen and phosphorus removal unit; wherein the ozone catalytic unit includes an ozone reactor (11) and a gas distributor (15) located at the bottom of the ozone reactor (11), and the nitrogen and phosphorus removal unit includes a nitrogen and phosphorus removal reactor (12). The solid-liquid separation system (2) includes a tubular filter membrane; the inlet of the tubular filter membrane is connected to the denitrification and phosphorus removal reactor (12) via a denitrification and phosphorus removal liquid delivery pipe (21), and the outlet of the tubular filter membrane is connected to the blending system (3) for sending the filtered effluent into the blending system (3); the concentrated liquid outlet of the tubular filter membrane is connected to a filter press (5); the outlet of the filter press (5) is connected to the denitrification and phosphorus removal reactor (12) via a pipeline for returning the filtered liquid phase for denitrification and phosphorus removal again.

8. The apparatus for preparing microbial denitrification carbon source from brewing wastewater according to claim 7, characterized in that, The denitrification and phosphorus removal reactor (12) is equipped with a first stirrer (13).

9. The apparatus for preparing microbial denitrification carbon source from brewing wastewater according to claim 7, characterized in that, The ozone generator (14) is connected to the gas distributor (15) via a pipe. The ozone generated by the ozone generator (14) is sent into the gas distributor (15) via the pipe, and then into the brewing wastewater of the ozone reactor (11) via the gas distributor (15).

10. The apparatus for preparing microbial denitrification carbon source from brewing wastewater according to claim 7, characterized in that, An overflow port is provided at the top of the ozone reactor (11), and the overflow port is connected to the denitrification and phosphorus removal reactor (12) via a pipe to allow the wastewater in the ozone reactor (11) to overflow into the denitrification and phosphorus removal reactor (12).

11. The apparatus for preparing microbial denitrification carbon source from brewing wastewater according to claim 7, characterized in that, The mixing system (3) includes a mixing tank (31); The mixing tank (31) is connected to the outlet of the tubular filter membrane via a filter outlet pipe (22). The mixing tank (31) is also connected to a sewage output pipe (33) for sending the mixed sewage as a carbon source to the sewage treatment plant.

12. The apparatus for preparing microbial denitrification carbon source from brewing wastewater according to claim 11, characterized in that, The mixing tank (31) is equipped with a second stirrer (32).

13. The apparatus for preparing microbial denitrification carbon source from brewing wastewater according to claim 11, characterized in that, The dosing system (4) includes an antifoaming agent storage tank (41), an alkali storage tank (42), and a formulation storage tank (43); the antifoaming agent storage tank (41) is connected to the ozone reactor (11) via an antifoaming agent delivery pipe (44), the alkali storage tank (42) is connected to the denitrification and phosphorus removal reactor (12) via an alkali delivery pipe (45), and the formulation storage tank (43) is connected to the formulation tank (31) via a formulation delivery pipe (46).

14. The apparatus for preparing microbial denitrification carbon source from brewing wastewater according to claim 13, characterized in that, Metering pumps are installed on the defoamer delivery pipe (44), the alkali delivery pipe (45), and the conditioning agent delivery pipe (46).

15. The apparatus for preparing microbial denitrification carbon source from brewing wastewater according to claim 11, characterized in that, A first pump (23) is installed on the denitrification and phosphorus removal liquid delivery pipe (21), and a circulation pump (24) is installed on the denitrification and phosphorus removal liquid delivery pipe (21) between the first pump (23) and the inlet of the tubular filter membrane. The concentrated liquid outlet of the tubular filter membrane is connected to the circulation pump (24) through a pipeline.

16. The apparatus for preparing microbial denitrification carbon source from brewing wastewater according to claim 15, characterized in that, A second pump (25) is installed on the filter outlet pipe (22), and a third pump (34) is installed on the sewage outlet pipe (33).

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