57 results about "Low dissolved oxygen" patented technology

The utility model provides a biological nitrogen and phosphorus removal system for sewage, and relates to the technical field of sewage treatment. The system comprises an anaerobic zone, a denitrification anoxic zone, a low dissolved oxygen aeration zone, a solid-liquid separation zone and an equipment zone which are sequentially communicated along a sewage flowing direction, all biochemical areas in the system are operated at high sludge concentration; the anaerobic zone is connected with a water inlet pipe; the solid-liquid separation area is provided with a drainage pipe; and the equipment area comprises stirring equipment and dissolved oxygen providing equipment. According to the biological nitrogen and phosphorus removal system for the sewage, provided by the utility model, the organic matter intake capacity and phosphate release capacity of microorganisms in the anaerobic zone can be improved, and synchronous nitrification and denitrification and denitrification phosphorus removal reaction can be promoted in the denitrification anoxic tank to remove nitrogen and phosphorus; synchronous nitrification and denitrification and phosphorus accumulation reaction can be performed in the low-dissolved-oxygen aeration area, organic matter removal is realized, no additional carbon source is needed, the aeration intensity is small, the operation energy consumption is low, and the treatment effect is good.

The invention discloses a biological enhancement treatment method for eucalyptus chemimechanical pulp high-concentration wastewater, and belongs to the technical field of toxic chemimechanical pulp high-concentration wastewater treatment. According to the method, the eucalyptus chemimechanical pulp high-concentration wastewater is taken as a treatment object, the biodegradability of the wastewater is improved through biological detoxification treatment, low-oxygen treatment is carried out after anaerobic treatment, organic pollutants are degraded under a low dissolved oxygen condition, and aerobic biological enhancement treatment and deep treatment are carried out through a short process, so that the removal rate of chemical oxygen demand is improved. According to the method disclosed by the invention, the biological detoxification tank is arranged before anaerobic treatment, and the toxicity-resistant microbial flora is screened and domesticated, so that refractory organic matters and antibacterial components in the eucalyptus chemithermomechanical pulp wastewater are treated, toxicity in the wastewater is removed, and the biodegradability of the wastewater is improved, so that the efficiency of subsequent biological treatment is optimized; compared with traditional long-time aerobic treatment, the treatment method disclosed by the invention has the advantages that most pollutants can be removed with lower energy consumption, and the energy consumption in the aerobic treatment process is effectively reduced.

The invention relates to the technical field of micro-ecology, in particular to a rhodococcus coryneform strain and application thereof in aquaculture. The invention discloses a strain of Rhodococcus corynobacteria, and the preservation number of the strain is CGMCC (China General Microbiological Culture Collection Center) No.23799. The invention further discloses a preparation method of the strain of Rhodococcus corynobacteria. The rhodococcus strain can oxidize sulfides under the condition of low dissolved oxygen, does not reduce the pH value of a water body, reduces sulfide pollution of an aquaculture water body, relieves bottom mud acidification, and has no toxic effect on cultured animals.

The invention relates to an aquaculture pond aerator capable of self-adaptive adjustment. The aerator comprises a water quality detection module, a central processing unit module and a control module, wherein the water quality detection module is used for collecting water environment parameters in an aquaculture pond in real time and sending the water environment parameters to the central processing unit module; the central processing unit module is used for determining the oxygenation demand of the water body and the area needing oxygenation based on the water body environment parameters, generating a control instruction and sending the control instruction to the intelligent navigation module and the self-adaptive oxygenation module; the intelligent navigation module is used for controlling the position and direction of the aerator on the basis of the control instruction in combination with inertial navigation system information and GPS position information, so that the aerator reaches an area needing oxygenation; the self-adaptive oxygenation module is used for controlling the aerator to carry out oxygenation based on the control instruction after the aerator reaches the area needing oxygenation; and the Internet of Things module is used for accessing each module to the Internet and providing remote monitoring and control. Dissolved oxygen distribution of a water body can be automatically detected, the position is adaptively moved to reach a low-dissolved-oxygen water area for oxygenation, and power output of the aerator is automatically adjusted according to the dissolved oxygen amount of the water body.

The utility model provides low dissolved oxygen sewage microbiological treatment equipment, which relates to the technical field of sewage treatment and comprises a storage main body, a filter screen mounted on the inner side of the storage main body, and a group of movably connected cleaning mechanisms above the storage main body, the cleaning mechanism is jointly composed of a first electric motor, a positioning block, a threaded rod, a scraping plate, a positioning rod, a tension spring and a sliding block, and two collecting shells are installed on the outer side of the storage body. The filter screen is arranged to filter sewage, the cleaning mechanism is arranged to achieve the effect of automatically cleaning the filter screen, meanwhile, the hidden danger that the filter screen is blocked is avoided, a scraping plate of an elastic structure is arranged in the cleaning mechanism, and the scraping plate can push out impurities adhering to the upper portion of the filter screen in the moving process.

The invention relates to a method for reducing dissolved oxygen in an MMA raw material solution, the MMA raw material solution and application of the MMA raw material solution, and the method comprises the following steps: (1) mixing the MMA raw material solution with nitrogen for gas replacement treatment to obtain a mixed MMA raw material solution; (2) decompressing and degassing the mixed MMA raw material liquid obtained in the step (1) to obtain mixed gas and MMA raw material liquid with low dissolved oxygen; and (3) sequentially pressurizing, condensing and separating the mixed gas obtained in the step (2) to realize separation of nitrogen, oxygen and the MMA raw material liquid. According to the method, the dissolved oxygen in the MMA raw material solution can be removed to 0.1 ppm or below, the polymerization reaction is completed by adopting a conventional polymerization process, and the PMMA material with excellent performance can be obtained.

The invention relates to the technical field of sewage treatment, and aims to solve the problems that a dissolved oxygen detector is limited in measuring range, an air inlet fan and an air inlet valve in a low-dissolved-oxygen area cannot be guided to act according to dissolved oxygen indexes, an efficient denitrification state cannot be maintained, a dephosphorization agent is added according to effluent total phosphorus, a dephosphorization agent adding point is the tail end of an aerobic II area, the feedback time is long, and the efficiency is high. The invention provides an optimized oxygen dissolving and dosing regulation and control method suitable for an A2O + MBR (Membrane Bioreactor) process, aiming at solving the problems of unstable total phosphorus in effluent caused by low control efficiency in the prior art. The method comprises the steps of data acquisition, medicament adding control and dissolved oxygen control. According to the invention, the opening degree of the fan and the joint action of the valves in the areas to be controlled are controlled through the oxidation-reduction potential, the linkage automatic control of the oxidation-reduction potential of the biochemical pool and the dissolved oxygen in the low dissolved oxygen area and the aerobic area is completed, the actions of the fan and the valves of the aeration system are effectively guided, and the efficient denitrification state can be maintained; the orthophosphate value at the tail end of the aerobic zone is used as the adding basis of the dephosphorization agent, so that the method is more accurate and efficient.

The invention provides a two-stage HRBPR-PN / A process and device based on sludge biological enhancement. In the front section of the process, an endogenous carbon source is taken in and phosphate is released in an anaerobic stage through phosphorus-accumulating bacteria (PAOs), and then excessive phosphorus is absorbed in an aerobic stage. And the rear stage is an anaerobic / aerobic alternate operation short-cut nitrification anaerobic ammonia oxidation (PNA) process, under the condition of low dissolved oxygen, ammonia oxidizing bacteria AOB and anaerobic ammonia oxidizing bacteria AnAOB cooperate to efficiently remove nitrogen, and meanwhile, residual organic matters in the previous stage and nitrate in the system are removed by strengthening endogenous denitrification. The method comprises the following steps: introducing residual sludge containing a small amount of AOB from an HRBPR section, and periodically adding the residual sludge into a PN / A reactor according to a volume ratio of 0.1-5%; according to the process, segmented DO control is adopted, NOB ecological niche inhibition and short-cut nitrification long-term stability are achieved, and synchronous deep nitrogen and phosphorus removal can be achieved without additional carbon sources and chemical agents. The device has the advantages of low energy consumption, low sludge yield, high operation stability and the like, and is suitable for energy-saving and efficient treatment of urban low-C / N-ratio sewage.

The application discloses a kind of Phascolosoma esculenta seedling cultivation methods, it is related to the technical field of mariculture.(1) parent culture;(2) labor induction;(3) sea ball larva cultivation;(4) the preparation of benthic cultivation pool;(5) planktonic larva metamorphosis induction;(6) the cultivation management of benthic larva.The application can effectively improve the efficiency of feeding sea mud of creeping stage larva, improve the dissolved oxygen in silt substrate, reduce the low dissolved oxygen caused by accumulated water during the process of dry, and the high mortality rate.

The present invention relates to a device and a screening method for screening living freshwater snails. The device comprises a zero dissolved oxygen zone and a high dissolved oxygen zone. The zero dissolved oxygen zone comprises a zero oxygen water tank and a zero dissolved oxygen water tank. The zero oxygen water tank and the zero dissolved oxygen water tank are connected through a first connecting pipeline. Freshwater snails are placed in the zero dissolved oxygen water tank and spread evenly. Zero oxygen water in the zero oxygen water tank is dispersed into the zero dissolved oxygen water tank through the first connecting pipeline. The dissolved oxygen concentration of the zero oxygen water is not higher than 1 mg / L. The present invention creates a low dissolved oxygen water body through the zero oxygen water in the zero oxygen water tank, so that the freshwater snails with good vitality quickly escape from the zero dissolved oxygen water tank after being stimulated by the zero oxygen water, thereby achieving the purpose of rapid screening. The operation is simple, the cost is low, and the labor intensity is greatly reduced.

The present disclosure relates to sterile concentrated tea extracts and tea beverages with a low dissolved oxygen level. An example method includes steeping tea leaves in water to extract the tea leaves and obtain a steeped tea, separating the tea leaves from the steeped tea, cooling the steeped tea to room temperature to obtain an initial tea extract, removing dissolved oxygen until a dissolved oxygen concentration of the initial tea extract is 5.0 mg / L or lower, and sterilizing the tea extract to obtain a sterile concentrated tea extract having a low dissolved oxygen level of 5.0 mg / L or lower and a Brix value of 0.3 to 3.3. The method of the present disclosure can be used to achieve reduced oxidation of tea polyphenols, achieve a flavor close to that of freshly brewed tea, delay quality degradation, and lower production costs.

The utility model discloses a touch control type on-line dissolved oxygen detection and analysis device, which relates to the technical field of dissolved oxygen detection and analysis and comprises a detection body and a touch display screen arranged at the upper end of the detection body, the lower end of the detection body is provided with a containing groove, and a detection probe is arranged in the containing groove in a sliding and penetrating mode. The lower end of the outer side of the detection body is covered with a plurality of sealing cover plates which are symmetrically arranged in a surrounding mode, the multiple sealing cover plates all cover the lower end of the detection probe, a rotating rod is rotationally arranged at the upper end of the interior of the detection body in a penetrating mode, the rod wall of the rotating rod is fixedly sleeved with a protection plate, the protection plate covers the outer side of the touch display screen, and the rear end of the rotating rod is fixedly sleeved with a rotating block. And a push-out use mechanism for driving the detection probe to move is arranged in the storage groove. The detection probe can be effectively sealed and protected in the storage process of the touch display screen, the detection probe is prevented from being influenced to reduce the detection precision of dissolved oxygen as much as possible, and the use effect of the device is improved.

This invention relates to the field of wastewater biological treatment technology, specifically to a device and method for improving the autotrophic denitrification performance of a MABR reactor. It employs a composite membrane module combining a curtain-type silica gel filament membrane with excellent oxygen permeability with a spatial three-dimensional mesh packing material that facilitates the attachment of anaerobic ammonia-oxidizing bacteria, thereby coupling part of the nitrification reaction with the anaerobic ammonia oxidation reaction. Through the circulating reaction zone and membrane reaction zone within the reactor, nitrate nitrogen generated by anaerobic ammonia oxidation and excess nitrite nitrogen during instability adjustment are circulated and removed, thus improving the total nitrogen removal efficiency of the reactor. By adding appropriate amounts of sodium nitrite solution at appropriate times, the free nitrite concentration in the reactor mixture is increased. Simultaneously, the intermittent aeration ratio of the MABR is controlled to achieve synergistic inhibition of nitrite-oxidizing bacteria activity by low dissolved oxygen and high free nitrite, allowing the unstable short-range nitrification reaction to recover and improving the autotrophic denitrification performance of the reactor.

This invention relates to a device and method for rapidly starting a short-cut nitrification process, belonging to the field of water treatment. The invention involves inoculating a secondary sedimentation tank with sludge and adding a polyurethane biological sponge carrier into a sequencing batch reactor (SBR). First, a phased influent influent + incremental post-aeration strategy (increasing aeration time first, then increasing aeration rate) is adopted. This utilizes nitrate and a dynamic oxygen environment to drive the migration of *Candidatus Contendobacter* to the sponge carrier and complete its enrichment and acclimatization, reducing the obstruction of O2 on the endogenous denitrification process of *Candidatus Contendobacter* under aerobic conditions. The phased influent influent is then eliminated, and NH4 is introduced. + -N synthesis wastewater is treated using a low-alkalinity strategy (reducing influent KHCO3 concentration) + post-aeration with an initial increase followed by a decrease in aeration volume, combined with strong NO2 stimulation from Candidatus Contendobacter in a low dissolved oxygen environment. ‑ -N reducing power inhibits NOB growth, enabling rapid start-up of the short-cut nitration process.

This invention discloses a gradient dissolved oxygen-guided multi-filler synergistic submersible aeration and purification device. The device includes: an aeration zone for aeration, with an aerobic layer with high dissolved oxygen content installed at the upper end of the aeration zone, an anoxic layer with low dissolved oxygen content installed at the upper end of the aeration zone, and an anaerobic layer installed at the lower end of the anoxic layer; the aeration zone includes an aeration cylinder with a permeable inner cylinder containing an aeration component that sprays air horizontally; the aerobic layer includes a first packing cylinder. The gradient dissolved oxygen-guided multi-filler synergistic submersible aeration and purification device provided by this invention, through the synergistic effect of aeration in the aeration zone and the gradient porosity packing layer, forms a stable dissolved oxygen gradient of "aerobic upper layer – anoxic middle layer – anaerobic lower layer," simultaneously meeting the functional requirements of nitrification, denitrification, and phosphorus removal.

The application discloses a method for rapidly improving river water dissolved oxygen, and belongs to the technical field of environmental protection. The method comprises the following technical steps: (1) water quality fluorescence fingerprint database establishment; (2) pollution source dissolved oxygen concentration gradient division; (3) low-oxygen discharge outlet dissolved oxygen and water flow determination; (4) water quality fluorescence fingerprint similarity comparison; and (5) river required ecological water flow calculation. The method comprises the following steps: establishing a water quality fluorescence fingerprint database, dividing a pollution source dissolved oxygen concentration gradient, determining low-oxygen discharge outlet dissolved oxygen and water flow, comparing water quality fluorescence fingerprint similarity, and calculating the ecological water flow required for river water dissolved oxygen to reach the standard. Then, the ecological water flow is dispatched to equivalently hedge the water body with low dissolved oxygen concentration in the river mainstream, so that the river water dissolved oxygen concentration can be simply, rapidly, efficiently and accurately improved, water resource waste in the water flow dispatching process is avoided, the method has good precision and strong operability, and is easy to popularize on a large scale.

The application discloses a short-process sewage treatment process with low dissolved oxygen operation, which adopts two-stage biochemical treatment to realize simultaneous nitrification and denitrification under the conditions of micro-dissolved oxygen (DO 0.5-1.5 mg / L) and low-dissolved oxygen (DO 1.5-2.5 mg / L); a new aeration mode combining cyclone aeration and micropore aeration is adopted to promote the fluidization of fillers, strengthen mass transfer, make the dissolved oxygen concentration controllable and not cause the abrasion of fillers; the mud film mixed mode is adopted to operate, and a low activated sludge concentration is set to guarantee that the ammonia nitrogen in the effluent meets the standard under the short process, and the residual sludge is reduced. The process greatly shortens the traditional denitrification process flow, significantly improves the denitrification efficiency, effectively reduces the aeration energy consumption under the low-dissolved oxygen operation, reduces the unnecessary aeration amount through fine aeration control, realizes energy saving and efficiency increase, and further reduces the number of process units, reduces the land occupation and construction cost.

This invention relates to an adaptive aerator for aquaculture ponds, comprising: a water quality monitoring module for real-time acquisition of aquatic environmental parameters in the aquaculture pond and transmission to a central processing unit (CPU) module; a CPU module for determining the oxygenation demand and required oxygenation areas based on the aquatic environmental parameters, generating control commands and sending them to an intelligent navigation module and an adaptive aeration module; an intelligent navigation module for controlling the position and direction of the aerator based on the control commands combined with inertial navigation system information and GPS location information, to reach the required oxygenation area; an adaptive aeration module for controlling the aerator to perform oxygenation based on the control commands after reaching the required oxygenation area; and an Internet of Things (IoT) module for connecting all modules to the Internet and providing remote monitoring and control. This invention can automatically detect the dissolved oxygen distribution in the water, adaptively move to areas with low dissolved oxygen for oxygenation, and automatically adjust the aerator's power output according to the dissolved oxygen level.

The invention relates to the technical field of environmental biology, and discloses a short-cut nitrification-denitrification complex microbial inoculant and a preparation method thereof. The method includes; the method comprises the following steps: respectively culturing ammonia oxidizing bacteria, denitrifying bacteria and heterotrophic nitrification-denitrifying bacteria, mixing, and co-domesticating under a low dissolved oxygen condition to obtain a co-domesticated flora; and then adding into sodium alginate-polyvinyl alcohol, immobilizing by a calcium chloride-boric acid-glutaraldehyde system, and freeze-drying to obtain the complex microbial inoculant. The prepared complex microbial inoculant can stably realize synchronous short-cut nitrification and denitrification under the condition of low dissolved oxygen, is high in nitrite accumulation rate, remarkably improves the removal rate of ammonia nitrogen and total nitrogen, has the advantages of stable flora structure, high denitrification efficiency and low operation energy consumption, and is suitable for industrial production. The method can be widely applied to biological nitrogen treatment of urban sewage and high-ammonia-nitrogen industrial wastewater.

The present invention discloses a method for bio-enhanced treatment of high-concentration wastewater from eucalyptus chemical mechanical pulp, and belongs to the technical field of treatment of high-concentration wastewater from toxic chemical mechanical pulp. The present invention takes high-concentration wastewater from eucalyptus chemical mechanical pulp as the treatment object, improves the biodegradability of the wastewater through biological detoxification treatment, performs low-oxygen treatment after anaerobic treatment, utilizes low dissolved oxygen conditions to degrade organic pollutants, and performs aerobic bio-enhanced treatment and deep treatment through a short process, thereby improving the removal rate of chemical oxygen demand. The present invention sets a biological detoxification pool before anaerobic treatment, screens and domesticates toxic-resistant microbial flora, so as to treat the difficult-to-degrade organic matter and antibacterial components in the eucalyptus chemical mechanical pulp wastewater, remove the toxicity in the wastewater, and improve its biodegradability, thereby optimizing the efficiency of subsequent biological treatment; compared with traditional long-term aerobic treatment, the treatment method of the present invention can remove most of the pollutants with lower energy consumption, effectively reducing the energy consumption in the aerobic treatment process.

The utility model relates to the technical field of water quality improvement, in particular to a water source ground layer water quality improvement system which comprises a water source pool, a circle of embankment is arranged on the edge of the water source pool, a protective fence is fixed to the embankment, and a plurality of water replacement assemblies are connected to the lower portion in the water source pool through adjusting assemblies. The device has the advantages that bottom water of the water source pool can be well pumped to the position above the water surface and flows back to the upper layer of the water surface, circulation is formed, oxygen is increased, a thermocline layer is effectively broken, and the water quality of the water source pool is improved. Therefore, the problems that bottom-layer water does not circulate, dissolved oxygen is low, and odor exceeds the standard are effectively solved.

A substrate processing method capable of suppressing corrosion of a conductive material on a surface of a substrate by supplying a liquid having a reduced concentration of dissolved oxygen onto the substrate. The substrate processing method includes: dissolving an inert gas in a liquid at not less than a saturation solubility to replace oxygen dissolved in the liquid with the inert gas; generating bubbles of the inert gas in the liquid by depressurizing the liquid in which the inert gas is dissolved; and processing the substrate while supplying the liquid containing the bubbles to the surface of the substrate.

The invention provides a method and system for removing high-concentration complex cyanogen in gold extraction wastewater, and relates to the technical field of sewage treatment.The method comprises the steps that the pH of the gold extraction wastewater is adjusted to 8-10, and pretreated wastewater is obtained; adding a cobalt ferrite particle catalyst into the pretreated wastewater, and introducing ozone to obtain oxidized effluent; dividing the oxidized effluent into a solution A and a solution B according to a volume ratio, oxidizing the solution A by using anaerobic ammonium oxidation bacteria under the condition of low dissolved oxygen, and mixing the oxidized solution A with the untreated solution B to obtain a mixed solution; enabling the mixed solution to react with anaerobic ammonium oxidation bacteria through a porous adsorption material, and recovering the cobalt ferrite particle catalyst for recycling. According to the method, the removal rate of the high-concentration complex cyanogen can be effectively increased, thorough mineralization of the complex cyanogen is achieved, and the core problem that the complex cyanogen is difficult to degrade is solved; and the method and the system have relatively high load resistance, are simple and convenient to operate and have good adaptability.

The invention relates to a method for preparing a sterile low-dissolved-oxygen concentrated tea extracting solution. The method comprises the following steps: a) extracting tea leaves with water for 1 minute to 2 hours; b) separating the tea leaves from the tea soup, and cooling the tea soup to room temperature or keeping the temperature of the tea soup at 5-25 DEG C to obtain an initial tea extracting solution; c) removing dissolved oxygen until the dissolved oxygen concentration of the initial tea extracting solution is below 5.0 mg / L; d) sterilizing to obtain a final sterile low-dissolved-oxygen concentrated tea extracting solution; wherein the Brix degree Brix of the sterile low dissolved oxygen concentrated tea extracting solution is 0.3 to 3.3. The invention also relates to a product obtained by the method, a tea beverage based on the product and a preparation method of the tea beverage. According to the method, oxidation of tea polyphenol can be reduced, the flavor of the tea beverage is close to that of the freshly-brewed tea, quality degradation is delayed, and the production cost is low.

The present invention belongs to the technical field of river water body treatment facilities, and in particular relates to an underwater forest ecological restoration structure. The present invention makes the ecological restoration effect of the underwater forest more prominent, flexible, and comprehensive by arranging a lifting suspension box unit, a lifting frame unit, and a porous strip unit on the water-retaining wooden pile unit. The present invention has the following advantages: First, the water-retaining wooden pile unit is high on both sides and low in the middle, so that the cleaning boat can pass normally, ensuring that the overall sewage treatment effect of the river is more prominent and comprehensive; second, the underwater forest structure includes submerged plants, emergent plants, and microorganisms, so that many water purification effects such as reducing the nitrogen and phosphorus content in the water, increasing dissolved oxygen, absorbing heavy metals, and settling suspended pollutants can be achieved.

The present invention provides a process for preparing a composition having a low dissolved oxygen content comprising acetaminophen and optionally one or more NSAIDs wherein the composition has a dissolved oxygen of at most 1.0 ppm in a closed container, said process comprising flushing the mixing container at least once with water at a temperature of at least 80 DEG C, and the composition obtained therefrom, thereby heating the container and creating a hypoxic environment in the container; and dissolving the acetaminophen in water for injection in the flushed container, the water for injection having a temperature of at least 80 DEG C wherein one or more NSAIDs are optionally added before or after dissolving the acetaminophen. The method of the present invention can produce a stable, intravenously administered aqueous composition without the need to deoxidize the composition.

This application relates to the field of rotifer culture technology and discloses a method for regulating rotifer body size. This application successfully controls the body size of marine rotifers by regulating factors such as dissolved oxygen, temperature, salinity, and feed. Specifically, the conditions for large-scale rotifer culture include relatively low dissolved oxygen, temperature, and a larger feed, while the conditions for small-scale rotifer culture include relatively high dissolved oxygen, temperature, and a smaller feed. Certain cyanobacteria can also be used as supplementary feed. This application stably controls the environmental conditions for marine rotifer body size and selectively modifies the feed for the rotifers, achieving the goal of selectively regulating the body size of marine rotifers.

The invention discloses a method for predicting the lowest dissolved oxygen of a rice and shrimp water body by using a random forest algorithm, and relates to the technical field of agricultural meteorological disaster risk early warning and assessment. The method comprises the following steps: collecting observation data of water temperature, water quality, dissolved oxygen and synchronous weather of water bodies at different depths of a rice and shrimp pond, and carrying out quality control processing on various observation data; analyzing comprehensive factors of the rice and shrimp water body low dissolved oxygen disaster process; analyzing a key driving factor influencing the lowest dissolved oxygen of the water body, and establishing a key variable data set based on daily scale; according to the method, the water temperature, water quality and dissolved oxygen of the rice and shrimp water body over the years and meteorological observation data above the rice and shrimp pond in the same period are systematically analyzed, the occurrence season and the occurrence time period of the low dissolved oxygen in the water body and other accompanying main control factors are screened out, and the disaster-inducing indexes of the low dissolved oxygen disaster are more accurately grasped; the method can truly reflect the influence of various other main factors on the low dissolved oxygen formation rule, and provides a more reliable scientific basis for forecasting the low dissolved oxygen in the rice and shrimp water body.

The application provides a method and system for removing high-concentration complex cyanide in gold extraction wastewater, and relates to the technical field of sewage treatment. The method comprises the following steps: adjusting the pH of the gold extraction wastewater to 8-10 to obtain pretreated wastewater; adding a cobalt ferrite particle catalyst to the pretreated wastewater and introducing ozone to obtain oxidized effluent; dividing the oxidized effluent into solution A and solution B according to the volume ratio, oxidizing solution A under the condition of low dissolved oxygen by using anaerobic ammonia oxidation bacteria, mixing the oxidized solution A with untreated solution B to obtain a mixed solution; and reacting the mixed solution with porous adsorption material and anaerobic ammonia oxidation bacteria, and recycling the cobalt ferrite particle catalyst for circulation. The method used by the application can effectively improve the removal rate of high-concentration complex cyanide, realizes complete mineralization of the complex cyanide, solves the core problem of difficult degradation of the complex cyanide, has strong load resistance, is simple to operate, and has good adaptability.

This invention discloses a method for enhanced nitrogen and phosphorus removal from wastewater with low carbon-to-nitrogen ratio using algae-bacterial granular sludge, comprising the following steps: inoculating an algae-bacterial symbiotic sludge into a sequencing batch reactor; introducing domestic sewage, performing low-DO aeration, subjecting the reactor to light treatment, and operating the reactor in an anaerobic / aerobic / anoxic mode, thereby forming algae-bacterial symbiotic sludge into algae-bacterial granular sludge; and controlling the dissolved oxygen concentration of the low-DO aeration to 0.4–0.6 mg·L⁻¹. ‑1 The inoculated sludge concentration is 4000-5000 mg / L. This invention employs low dissolved oxygen aeration combined with lighting to drive algae and bacteria granular sludge to achieve endogenous carbon compensation, significantly reducing the carbon source demand in the denitrification and phosphorus removal process of low carbon-to-nitrogen ratio wastewater, lowering wastewater treatment operating costs, and avoiding secondary pollution caused by carbon source addition.