68results about How to "Improve the effect of flocculation and sedimentation" patented technology

The invention discloses a composite medicinal preparation for biochemical effluent deep treatment of a sewage plant, and belongs to the technical field of sewage treatment. The composite medicinal preparation comprises the following raw materials in parts by weight: 500 parts of modified attapulgite, 25 to 55 parts of inorganic strong base, 300 to 550 parts of inorganic aluminum salt, 100 to 200 parts of inorganic ferric salt, and 400 to 650 parts of inorganic strong acid sodium silicate solution. The preparation method comprises the following steps: copolymerizing the modified attapulgite, the inorganic ferric salt and the inorganic aluminum salt; further performing secondary polymerization with the inorganic strong acid sodium silicate; regulating the basicity of the reaction mixture after secondary polymerization to 60-85 percent by using the inorganic strong base; and drying and grinding. The composite medicinal preparation is mainly suitable for biochemical effluent deep treatment of the sewage plant, has the functions of COD (chemical oxygen demand) enhanced removal, adsorption bleaching, auxiliary phosphor removal and the like and has good treatment effect; moreover, the preparation method is simple and easy to operate.

The invention discloses a method for preparing a polysilicate ferro-aluminum sulfate composite flocculant from red mud waste. The method comprises the following steps: (1) putting red mud waste and anactivating agent into a muffle furnace to be roasted and grinding the red mud waste to obtain activated red mud powder; (2) putting an oxidizing agent and the activated red mud powder into a sulfuricacid solution to react; (3) adding adjusting salt to adjust a molar ratio of Fe to Al to Si in the solution as 1 to 1 to (0.2 to 0.7), utilizing a pH conditioning agent to adjust a pH of the solutionto 1 to 6; (4) adding a stabilizer to react and filtering to obtain the polysilicate ferro-aluminum sulfate composite flocculant. By means of the method disclosed by the invention, ferric oxide, aluminum oxide and silicon oxide in the red mud waste are effectively utilized to prepare the polysilicate ferro-aluminum sulfate composite flocculant; not only are the problems that the waste red mud occupies a lot of land and pollutes underground water are solved, but also the waste red mud can be resourcefully utilized, production cost is low, added value of products is high, and a novel way for comprehensively utilizing the red mud waste is provided.

The invention belongs to the technical field of waste water treatment equipment, and discloses a car-washing waste water treatment device. The car-washing waste water treatment device comprises a waste water collecting tank, wherein a plurality of collecting holes are formed in the top of the waste water collecting tank; the waste water collecting tank is communicated with a sediment tank through a water pump; a water outlet of the water pump is close to the bottom of the sediment tank; a dosing device for adding flocculating agent is arranged on the sediment tank; the sediment tank is communicated with a filter tank through a pipe; a first filter plate and a second filter plate are arranged in the filter tank; the pipe penetrates through the first filter plate and the second filter plate; the outlet end of the pipe is located below the second filter plate; the filter tank which is located above the first filter plate is equipped with a water discharging pipe; the water discharging pipe is communicated with an active carbon filter; the active carbon filter is further communicated with a disinfecting tank; an ozone generator is arranged on the disinfecting tank; the disinfecting tank is communicated with a clean water reservoir. The car-washing waste water treatment device is simple in structure and low in treatment cost, has a good treating effect because the car-washing waste water treatment device can perform multi-stage purification treatment including flocculent precipitation, filtering by the filter plates, filtering by the active carbon filter, ozone disinfection and so on, and can be widely popularized to be used.

The invention relates to a method for preparing polyaluminum chloride, in particular to a method for preparing low-residual-aluminum polyaluminum chloride. The method is mainly used for solving the technical problem that in the prior art, when polyaluminum chloride serves as a flocculating agent in water high in pH or alkalinity, residual aluminum in the water exceeds the national drinking water standard, namely the concentration is larger than 0.2 mg / Kg. The method includes the steps that firstly, hydrochloric acid and an aluminum-containing raw material are put in a closed reaction kettle and fully stirred, water, calcium aluminate powder or sodium aluminate is added into polyaluminum chloride liquid in the closed reaction kettle, the mixture is discharged to a stirring tank through filter pressing after reaction is completed, and 50-150 Kg of a sodium dihydrogen phosphate and disodium hydrogen phosphate mixed aqueous solution is added into each ton of the mixture in the stirring tank, wherein the sodium dihydrogen phosphate and disodium hydrogen phosphate mixed aqueous solution comprises, by mass fraction, 20-30% of sodium dihydrogen phosphate, 5-15% of disodium hydrogen phosphate and the balance water; the finished polyaluminum chloride is obtained after stirring.

The invention discloses efficient flocculant for improving the yield of stevioside. The efficient flocculant comprises, by weight, 30-40 parts of modified lignin, 25-35 parts of modified polymerization ferric sulfate, 3-6 parts of polyaluminum ferric chloride, 12-15 parts of polyaluminium sulfate, 4-8 parts of magnesium citrate, 12-20 parts of xanthan gum, 2-3 parts of activated carbon, 1-2 parts of kieselguhr and 2-4 parts of zeolite powder. The efficient flocculant for improving the yield of stevioside is fast in flocculoreaction, the production period is shortened, and particles of a flocculating constituent are large, and are easy to separate.

The invention relates to a flue gas cleaner with integration of desulfurization, denitrification, mercury removal and dust removal. The flue gas cleaner comprises an integrated cleaning tower arranged on a base, a spiral flue duct, a dry absorbing and cleaning agent applying device and a wet absorbing and cleaning agent applying device, wherein an automatic slag remover, a flocculation and precipitation cleaning working zone, an inner precipitation circulating zone and an outer precipitation circulating zone are arranged in the base; an inner wall cleaning fluid collecting water channel is formed between the inner precipitation circulating zone and the outer precipitation circulating zone; the outer precipitation circulating zone is divided to form winding paths by a transverse partition board; the integrated cleaning tower is divided into a demisting and dewatering cleaning working zone, an absorption cleaning working zone and an oxidation cleaning working zone by a gas-water separator; an annular sprayer, a backwash cylindrical sprayer and a demisting filter screen are arranged in the demisting and dewatering cleaning working zone respectively; a main cylindrical sprayer is arranged in the absorption cleaning working zone; a cylindrical oxidation cleaning agent sprayer is arranged in the oxidation cleaning working zone; a flue gas outlet and a spray circulating system are arranged at the top of the integrated cleaning tower respectively. The flue gas cleaner has significant cleaning effect.

The invention discloses flocculant capable of improving the refining efficiency of stevioside. The flocculant comprises, by weight, 12-18 parts of modified chitosan, 20-30 parts of modified aluminum polychlorid, 20-25 parts of polymeric ferric sulfate, 12-20 parts of ferric citrate, 8-12 parts of magnesium sulfate, 15-25 parts of polymeric ferric silicate-sulfate, 5-7 parts of activated carbon and 1-2 parts of bentonite. According to the flocculant capable of improving the refining efficiency of stevioside, flocculoreaction is quick, the production cycle is shortened, flocculating constituents are large in particle and easy to separate, and glucoside cannot be adsorbed by flocculent precipitate easily.

The invention discloses an energy-saving sewage precipitation device which comprises a precipitation tank fixedly connected with a base; a conical cavity is formed in the precipitation tank, and a water inlet pipe is fixedly connected with the left side of the precipitation tank; a central shaft is arranged in a central axis position of the conical cavity, and a stirring plate is fixedly connectedwith the central shaft; and a spray pipe is arranged above the stirring plate, a liquid inlet pipe is communicated above the central shaft through a rotating joint, and a liquid storage tank is communicated with the liquid inlet pipe. The energy-saving sewage precipitation device disclosed by the invention has the benefits that as the conical cavity and the water inlet pipe tangentially communicated with the conical cavity are arranged, water flow enters the conical cavity to form rotational flow so as to drive the stirring plate to rotate, accelerate the dispersion of a flocculating agent, improve the mixing uniformity of the flocculating agent and improve flocculation and precipitation effects; and through arranging a solar-powered drive motor, the rotating speed of the stirring plate is further improved, the mixing effect of the flocculating agent is improved, and the flocculation and precipitation effects are better while the energy conservation is achieved.

The invention discloses a treatment system for electroplating wastewater, and relates to the technical field of sewage treatment. The system comprises a natural sedimentation pond, a chromium breakingreaction tank, a neutralization reaction tank, a first flocculation and precipitation pond, an electrolysis tower, a second flocculation and precipitation pond and a comprehensive filtering device which are successively connected, the chromium breaking reaction tank is connected with an acid agent addition box and a reduction agent addition box in sequence, and the neutralization reaction tank isconnected with organic processing cleaning water, nickeling wastewater, coppering wastewater and an alkaline agent addition box; filtration partition plates are obliquely arranged in the first and second flocculation and precipitation ponds, lifting devices are connected with the filtration partition plates, and spinous inverse hooks are arranged on the end surfaces of the filtration partition plates; the filtration partition plates are connected with floating balls through ropes, a setting agent is arranged in the floating balls, in the electrolysis tower, scrap iron is used as an anode, carbon granules are used as a cathode, the wastewater is used as an electrolyte solution, so that a tiny primary battery is formed, and the electrolysis tower is connected with an aeration device and theacid agent addition box; the system has the advantages of improving the quality and efficiency of treating the electroplating wastewater.

The invention discloses an oily wastewater adsorbent and a preparation method thereof. The oily wastewater adsorbent is prepared from coal ash, rape straws, calcium hydroxide, magnesia, ethyl orthosilicate, ferroferric oxide and the like. The straws are mixed with the coal ash, by the aid of loose porous excellent carrier performances, the magnesia is modified to prepare particles, the finished adsorbent particles have the advantages of light weight, high chemical stability and the like, environmental pollution is avoided, the oily wastewater adsorbent is simple to operate, low in cost and recyclable, the concentration of residual COD (chemical oxygen demand) and the like in wastewater meets national emission requirements after adsorption treatment is performed on the oily wastewater, andthe oily wastewater adsorbent is suitable for large-scale oily wastewater treatment.

The invention discloses an integrated oil and turbidity removing device which comprises a device body; a clarification zone is arranged at the upper part of the device body, and a mud settling zone isarranged at the lower part; symmetrical mud collecting hoppers are arranged under the mud settling zone; a flocculation reaction chamber is divided into a first flocculation reaction chamber and a second flocculation reaction chamber; the first flocculation reaction chamber is embedded in the second flocculation reaction chamber and is communicated with the second flocculation reaction chamber through the open lower end of the first flocculation reaction chamber; a slag collecting hopper is connected under the second flocculation reaction chamber; a water outlet is formed above the second flocculation reaction chamber and is close to the symmetrical mud collecting hoppers; the symmetrical mud collecting hoppers comprise two symmetrical mud hopper cone plates; an included angle between each of the mud hopper cone plates and a horizontal plane is 45 degrees; a roof structure with an included angle of 90 degrees is formed between the two mud hopper cone plates. The integrated oil and turbidity removing device disclosed by the invention has the benefits that all the functions of a chemical oil remover and a high-speed filter are combined, and the floor area is reduced.

The invention provides a composite cationic polyacrylamide flocculant and a preparation method thereof. The composite cationic polyacrylamide flocculant comprises the following raw materials in partsby weight: 50-80 parts of starch polyacrylamide, 20-50 parts of activated silicic acid, 0.9-2 parts of liquid polyaluminum chloride, 0.1-0.5 part of a stabilizer, 7-12 parts of zinc sulfate, 7-12 parts of magnesium sulfate and 1-5 parts of a borax solution. In the present invention, the activated silicic acid can increase the polymerization degree of the polyaluminium chloride and adjust the internal charge structure of the polyaluminium chloride; the activated silicic acid interacts with aluminum ions in the system to generate larger polymer (polyaluminum silicate chloride), and the polyaluminum silicate chloride simultaneously has three functions of electrostatic neutralization, adsorption bridging and net capture in the wastewater treatment process, so that the flocculation settling capacity of the composite flocculant is enhanced, and the obtained flocculant is relatively moderate in price and relatively high in cost performance.

The invention discloses a coal chemical wastewater pretreatment method. The method includes flocculent settling treatment, hydrogen peroxide catalytic oxidation treatment and internal electrolysis treatment, and effluent quality reaches that COD is smaller than or equal to 500mg / L, ammonia nitrogen content is smaller than or equal to 200mg / L, and suspended matter content is smaller than or equal to 70mg / L after treatment. After treatment according to the pretreatment method, wastewater available for biochemical treatment is obtained and can be directly discharged or recycled after biochemicaltreatment. A treatment system is stable in operation, and biochemical degradability of coal chemical wastewater is effectively achieved. The coal chemical wastewater pretreatment method and the pretreatment system have positive popularization significance and remarkable application value.

The invention discloses a kitchen waste treatment method. The kitchen waste treatment method comprises the steps of kitchen waste sorting and crushing, microbial fermentation decomposition, oil-water separation, aeration air flotation separation, hydrolysis-anaerobic fermentation, A / O tank treatment, hydrolysis-MBR treatment and disinfection treatment. The effluent quality reaches the discharge or reuse standard, the whole treatment process is carried out at normal temperature, high-temperature drying is not needed, the defects that in the prior art, kitchen waste treatment needs high-temperature treatment, energy consumption is high, and the decrement rate is low are overcome, kitchen waste treatment in the normal-temperature aerobic environment is achieved, energy consumption is low, the decrement rate reaches up to 99%, final products obtained after organic matter decomposition are carbon dioxide and water, no secondary pollutant is generated, environmental pollution is reduced, and the environmental comprehensive treatment capability of kitchen waste treatment is greatly improved.

The invention belongs to the technical field of chelating agents, and in particular relates to a synthesis method of a heavy metal chelating agent. The synthesis method comprises the steps of 1, adding excess carbon disulfide to active polymer aliphatic amine under an alkaline condition to enable active polymer aliphatic amine to react with the excess carbon disulfide so as to obtain an intermediate product, wherein the active polymer aliphatic amine is at average molecular weight of 200,000 to 300,000; 2, adding hydroxide powder to the intermediate product, agitating, and then performing solid-liquid separation to obtain the heavy metal chelating agent. Compared with the prior art, the synthesis method has the advantages that the prepared heavy metal chelating agent with relatively large average molecular weight is added to heavy metal ion containing wastewater to greatly improve the capacity of flocculating settling after reacting with the heavy metal ion, and therefore, the problem of pollution caused by wastewater with relatively low heavy metal concentration can be effectively solved.

The invention discloses a modified dicyandiamide formaldehyde-mimic enzyme compound sewage treatment agent. The sewage treatment agent is prepared from 20 to 50 parts by mass of a modified dicyandiamide formaldehyde polymer, 1 to 5 parts by mass of ethylene diaminetetraacetic acid tetrasodium salt, 5 to 20 parts by mass of ferrous sulfate heptahydrate, 1 to 3 parts by mass of polyferric sulfate, 1 to 5 parts by mass of calcium sulfate and 2 to 6 parts by mass of aluminum sulfate. A modifier of the modified dicyandiamide formaldehyde polymer is ethylenediamine or N-dihydroxyaniline or 2-imidazolidinone. The invention utilizes combination of a mimic enzyme technology and the modified dicyandiamide formaldehyde to improve the reaction efficiency of oxidation, complexation and polymerization of the mimic enzyme and organic pollutes. The sewage treatment agent realizes stable mimic enzyme catalysis and has good organic pollutants and chroma removal effects and has a low cost.

The invention discloses sewage and sludge separation and cyclic utilization equipment for constructional engineering, relates to the technical field of sewage treatment equipment, and solves the problems that in existing sewage equipment, a traditional rotary stirring part integrally stirs sewage, the sewage around a flocculating agent spray pipe cannot be accurately stirred, and the sewage treatment efficiency is low, and therefore the problem of insufficient diffusion and mixing of the flocculating agent and the sewage is solved. The equipment comprises a sewage tank that comprises a rail groove, a positioning ring, a transmission shaft and a positioning shaft, the sewage tank is of a rectangular structure as a whole, a cover plate is tightened and fixed to an opening in the top end, andtwo water inlet pipelines are symmetrically and vertically welded to the cover plate in a supporting mode; and four vertical rail grooves are symmetrically formed in the front inner wall and the rearinner wall of the sewage tank. The four expansion plates arranged in a surrounding manner can synchronously expand, support, gather and slide to precisely stir sewage around the feeding spray pipe, so that a flocculating agent sprayed by the feeding spray pipe can be fully stirred and diffused to be mixed and react with the sewage.

The invention discloses a physicochemical sewage processing system and method for simultaneously removing COD and total phosphorus. The sewage processing system comprises an improved reaction tank, animproved horizontal flow sedimentation tank, a magnetic powder recovering system, and a sludge discharge system. The improved reaction tank is divided into a coagulation reaction region, a magnetic powder loading region, and a flocculation reaction region. Between the improved reaction tank and the improved horizontal flow sedimentation tank, a water distribution adjusting region is arranged. A flow adjusting device and a triangular guide plate are arranged in the water distribution adjusting region. A horizontal pipe is arranged in the upper layer of the improved horizontal flow sedimentation tank, and a mud scraper is arranged on the bottom of the improved horizontal flow sedimentation tank. The magnetic powder recovering system comprises a separation groove, a cutting machine, and a magnetic separator, which are arranged in sequence. The sludge discharged from the bottom of the improved horizontal flow sedimentation tank is introduced into the separation groove through a pipeline;the separation groove is provided with two sludge discharge pipelines; one of the sludge discharge pipelines is connected to the magnetic powder loading region of the improved reaction tank, the otherone is connected to the cutting machine; and the magnetic powder separated by the magnetic separator is added into the magnetic powder loading region again. The provided system and method can efficiently remove COD, TP, and SS.

The invention discloses an anaerobic biogas slurry treatment process, and belongs to the related technical field of anaerobic biogas slurry treatment. The anaerobic biogas slurry treatment process comprises the following steps: step A: aeration, step B: precipitation, step C: filter pressing, step D: catalytic oxidation, step E: MBBR, step F: RO / AC, and step G: discharge. The invention further discloses anaerobic biogas slurry treatment equipment which comprises supporting legs, a treatment box is fixedly connected to the top ends of the supporting legs, a feeding pipe is fixedly connected tothe middle of the top end of the treatment box, air cylinders are fixedly mounted in the middles of the two sides of the treatment box, and telescopic rods are fixedly connected to the middles of onesides of the air cylinders. In treatment process,biogas slurry is subjected to aerobic aeration treatment through efficient micro-nano air active oxygen bubbles, anaerobic microorganisms in the biogasslurry are killed or are promoted to sleep, and suspended solids and organic matters in the biogas slurry are oxidized at the same time, so that the flocculating settling effect is improved. Resultsshow thatbiogas slurry flocculation and sedimentationeffect is impossible to achieve without aerobic aeration treatment.

The invention relates to the technical field of sewage treatment, and discloses an efficient flocculation precipitation system. In order to improve the efficient performance of sewage flocculent precipitation, the number of mixing tanks is eight, the number of flocculation tanks is four, the number of precipitation tanks is four, the number of mud plants is two, every two groups of mixing tanks are in one-to-one correspondence with one group of flocculation tanks, the flocculation tanks are in one-to-one correspondence with the precipitation tanks, and the mud plants are positioned between the flocculation tanks and the precipitation tanks. The system has the advantages that the removal effect of phosphorus and suspended solids in sewage can be improved for water entering the system while the adding amount of a flocculant is calculated and controlled according to the water quality condition, so that the flocculation and sedimentation effect is improved, the suspended solids and total phosphorus are effectively removed (the removal rate of the suspended solids is larger than 60%, and the removal rate of the total phosphorus is larger than 80%), the labor cost can be reduced, and the high efficiency of flocculent precipitation can be improved.

The invention relates to a method for deep oxidation treatment on organic wastewater by activating peroxymonosulfate based on visible light-assisted complexing iron ions. The method comprises the following steps: adding PMS (peroxymonosulfate) into initial organic wastewater, performing sufficient mixing, adding a mixed liquid of an oxalate and a trivalent iron salt, performing irradiation with anLED (light emitting diode) lamp and performing a stirring reaction synchronously, adding an alkali liquid and calcium hydroxide, and performing uniform stirring and precipitation, so as to effectively reduce CODcr (dichromate oxidizability) in supernatant tail water. By adopting the method, under the condition that the initial pH value of wastewater is not adjusted, iron ion precipitation is controlled by using a complexing agent, and under the action of visible light, circulation generation of ferrous ions is promoted, the PMS is continuously catalyzed and activated to produce strongly oxidized sulfate radicals, organic pollutants can be effectively oxidized and degraded, and thus CODcr in wastewater can be effectively removed. The method has the characteristics of being good in operability, low in energy consumption, wide in pH value application range, good in oxidation reaction continuity, high in organic matter oxidation degradation efficiency, and the like, and has great application potential in the field of deep wastewater treatment.

The invention discloses a cadmium pollution adsorbent and a preparation method thereof. The cadmium pollution adsorbent is prepared from raw materials of brown alga, glucose, magnesite, tetraethoxysilane, ferroferric oxide powder and the like. According to the cadmium pollution adsorbent and the preparation method thereof, the brown alga is used as a biological adsorbent, and the adsorption capacity of the brown alga is increased by crosslinking modification; the brown alga is combined with the modification magnesite under the adhesion of the glucose, and then carries manganese dioxide throughimpregnation of potassium permanganate to add ion exchange and complexing for cadmium to repair cadmium pollution. Compared with the prior art, the cadmium pollution adsorbent disclosed by the invention realizes relatively high adsorption efficiency and achieves a relatively good repair effect under a condition of use of a small number of repair agent, and no pollution is caused to the environment.

The invention belongs to the technical field of environmental protection, and particularly relates to a sewage recovery device with multiple filtering functions. The sewage recovery device comprises acover body and a tank body, the cover body and the tank body are detachably connected through bolts, the side wall of the tank body is fixedly connected with multiple groups of water inlet pipes, andthe water inlet pipes are provided with a filter assembly in a matched manner. The filter assembly comprises a support, an outer filter screen and an inner filter screen, one end of the outer filterscreen is fixedly connected with the support, the support is slidably connected with the tank body, the other end of the outer filter screen is movably connected with the inner filter screen through atransmission mechanism, the inner filter screen is fixedly connected with a water outlet pipe, and the water outlet pipe is slidably connected with the cover body. By arranging the sewage recovery device with the multiple filtering functions, the multiple filtering effects are achieved in the sewage recovery treatment process, the sewage treatment time is shortened in cooperation with dosing, mixing and precipitation, the sewage recovery efficiency is improved, secondary utilization of sewage can be rapidly achieved, and the sewage treatment cost is reduced.

The invention belongs to the technical field of production of soybean protein isolate, in particular relates to an acid precipitation system for the soybean protein isolate, and further discloses an acid precipitation method of the soybean protein isolate. The acid precipitation system comprises an acid precipitation tank and a precipitation tube bundle which are sequentially connected; spacer plates with flow through holes in different positions are additionally arranged on the acid precipitation tank, so that a flow path of acid precipitate liquid in a reaction cavity can be changed, the flocculation time of the acid precipitate liquid is further prolonged, the pH value stability rate of the acid precipitate liquid is accordingly increased, and the extraction efficiency of a final product is further increased; the precipitation tube bundle is used for enhancing the effect of flocculation-precipitation, and is beneficial to protein molecular flocculation so as to enlarge protein particles and further enhance the flocculation effect, so that a material is easier to separate in subsequent centrifugal treatment, protein loss in legumelin is effectively reduced, and the protein yieldis increased.

The invention relates to a method for removing mercury in the process of acid making with lead-zinc smelting flue gas, belonging to the technical field of flue gas treatment. Efficient mercury removalin the process of acid making is realized by adding a complexing agent I at the primary power wave, adding a complexing agent II to a gas-phase pipeline from an intermediate washing tower to a secondary power wave, and adding the complexing agent I at a secondary power wave; finally, mercury content in sulfuric acid in the dry absorption section is lower than 0.002%, the mercury content in finished product acid after standing is lower than 0.001%, and the requirement of superior product of industrial sulfuric acid is achieved; furthermore, the mercury removing method is steady in mercury removing efficiency, simple in mercury removal process, strong in adaptability, and favorable for transformation of existing devices, and addition of new equipment is not needed.

The invention provides a preparation and purification method of stevioside and application of the stevioside in an anti-fatigue product, and relates to the technical field of extraction. The preparation and purification method specifically comprises the following steps of (1), extraction: mixing stevia rebaudian and an extracting agent and then conducting reflux extraction to obtain an extracting solution A; (2) flocculating and precipitating: adding a flocculating agent into the extracting solution A, conducting filtering to remove precipitate to obtain filtrate; and (3) secondary extraction, refining and concentration: carrying out secondary extraction on the filtrate by using an adsorption column, conducting treatment through a refining column, and conducting concentrating, wherein the flocculating agent is prepared from polyferric sulfate, activated carbon, ferrous sulfate, ferric citrate, glycine iron, edible seaweed powder, starch and zeolite powder. By optimizing the components of the flocculating agent and the whole method, the impurity removal rate and the extraction rate can be effectively improved, the loss rate is reduced, and the product prepared by taking the stevioside obtained by the method as the raw material has an excellent anti-fatigue effect.

The invention discloses a coaxially-rotary stirring clarification tank. The coaxially-rotary stirring clarification tank comprises a driving motor, a planetary gear set, a clarification tank housing,an inner cylinder, an outer cylinder, a gas lift pipe, a mud guide pipe, a stirring and lifting impeller, a stirring and precipitating impeller and a water inlet pipe. The planetary gear set is connected with the driving motor and the clarification tank housing; an annular gear of the planetary gear set is hollow, and an output shaft of the driving motor is connected with a sun gear and the stirring and lifting impeller located in the inner cylinder; a planet carrier is fixedly connected with the inner cylinder; the sun gear is connected with the top of the outer cylinder; the bottom of the outer cylinder is connected with the stirring and precipitating impeller; the bottom of the clarification tank housing is fittingly connected with the mud guide pipe, and the gas lift pipe is fittinglyconnected with an opening at the bottom of the mud guide pipe; the water inlet pipe penetrates the wall of the clarification tank housing to be fittingly connected with the bottom of the inner cylinder. The coaxially-rotary stirring clarification tank has the advantages of large-scale industrialized production, effectively reduced production cost, improved production efficiency, and improved watertreatment effect.

The invention relates to a method for treating low-temperature low-turbidity water, in particular to a method for treating low-temperature low-turbidity water through ultrasonic enhanced coagulation. The method aims to solve the problems that in an existing method for treating the low-temperature low-turbidity water, the dosage of coagulant is large, and the purification effect is poor. The method comprises the steps that an ultrasonic processor is mounted on a low-temperature low-turbidity water inlet pipeline, and a coagulant adding opening is formed in the position, 10 m to 60 m away from the tail end of the ultrasonic processor, of the inlet pipeline; the low-temperature low-turbidity water is injected, meanwhile the ultrasonic processor is started, and when the low-temperature low-turbidity water after ultrasonic treatment flows through the coagulant adding opening, the coagulant is added, the low-temperature low-turbidity water with the coagulant is finally collected in a settling pond, settling is carried out for certain time, and therefore the low-temperature low-turbidity water is treated. The method is mainly used for treating the low-temperature low-turbidity water.