55results about How to "Improve nitrogen removal effect" patented technology

The invention discloses a composite carbon source for sewage denitrification as well as preparation and using methods of the composite carbon source. The composite carbon source comprises the following raw materials in parts by weight: 15 parts of sodium acetate solution with the concentration being 35%, 8 parts of glucose solution with the concentration being 45%, 6 parts of xylitol solution withthe concentration being 65%, 28 parts of glycerol, 25 parts of methanol with the purity being 99%, 4 parts of ethanol, 15 parts of glycol, 6 parts of glacial acetic acid, 5 parts of active peptide and 14 parts of composite amino acid solution with the concentration being 48%. The composite carbon source disclosed by the invention is a carbon source product more easily absorbed and utilized by microorganisms, all the raw materials of the composite carbon source are common substances, however, the compounded carbon source avoids the phenomenon that a single carbon source results in microbial acclimation to affect decarburization, therefore, the phenomenon that nutrient absorption of other microorganisms is inhibited due to mass propagation of a certain single microorganism cannot appear, and adverse effects on other bacteria can be avoided while denitrification is promoted; and the conversion rate of the composite carbon source from COD to BOD5 can reach up to about 85%.

The invention relates to a city watercourse drain outlet sewage treatment method. The method mainly comprise the steps of regulation, wherein sewage is introduced into a regulating reservoir for regulation; mixing with flocculant, wherein sewage in the regulating reservoir is led out to be mixed with flocculant; flocculent settling, wherein sewage mixed with flocculant is sequentially introduced into a baffle flocculation reaction tank and a settling tank for sewage flocculation and sludge precipitation separation; denitrification, wherein water discharged from the settling tank and part of water discharged from a nitration aerating filter are introduced into a denitrification filter for denitrification; aerobiotic nitration, wherein water discharged from the denitrification filter is introduced into a nitration aerating filter for nitration; filtration, wherein part of water discharged from the nitration aerating filter is introduced into a filtering device for filtration. The invention further provides a sewage treatment device adopting the method. The sewage treatment device comprises a regulating reservoir, a pipeline mixer, a baffle flocculation reaction tank, an oblique plate settling tank, a denitrification filter, a nitration aerating filter and a clear water pond which are connected in series, wherein a water outlet pipeline of the clear water pond is connected to a filter device.

A process for effectively screening the nitrogen cycling bacteria used to repair the ecological environment of water and treat water includes such steps as acquiring the water sample containing local nitrogen cycling bacteria, respectively preparing the culture media for ammonifying bacteria, nitrosifying bacteria, nitrifying bacteria and denitrifying bacteria, culturing, separating, purifying and using the bacterium with high conversion rate as the preferable one.

The invention provides a novel wastewater treatment device, aiming to solve the problem of domestic wastewater treatment of the traditional ship and aiming to the special requirements on the ship. The device integrates coarse filtration, anaerobic biological treatment, fine filtration and aerobic biological treatment into a whole and adopts an embedded membrane filtering technology. A depositing chamber is internally provided with a coarse filter, and the coarse filter can automatically carry out ventilation washing according to the preset time to prevent blockage without artificial cleaning. Water is output through coarse filtration and enters a baffling chamber, an organic matter is further precipitated and degraded, output water thereof flows into a regulation chamber, and water inflow and uneven water quantity are automatically regulated through the regulation chamber. Output water of the regulation chamber is pumped into an external fine filter through a pump, filtered wastewater enters a membrane bioreactor, and the wastewater which accords with a drainage standard is drained after treatment. The wastewater treatment equipment and the method for the ship ensure that wastewater treatment reaches a new national drainage standard; and the equipment satisfies the requirements for low energy consumption and easy maintenance and cleaning.

The invention discloses a secondary aluminum ash alkalescent washing harmless treatment method, belongs to the technical field of aluminum ash treatment, and adopts a technical method for hydrolyzing aluminum nitride in a high-temperature water bath heating environment by doping an alkalescent catalyst. According to the method, the problems that in the harmless treatment process of the secondary aluminum ash, a traditional chemical treatment method is difficult to separate, high in manufacturing cost, prone to generating secondary hazardous waste, very difficult to apply to concrete mineral admixtures and the like are solved, aluminum nitride in the secondary aluminum ash can be remarkably removed, and the volatilization toxicity of the secondary aluminum ash is effectively reduced.

The invention discloses an artificial wetland sewage treatment system, which comprises a sedimentation tank, an aeration tank, a microelectrolysis packing drum, a first reaction tank, a second reaction tank, a third reaction tank, a water collection tank and a control system in sequential arrangement from left to right. The first reaction tank, the second reaction tank, the third reaction tank andthe water collection tank are arranged sequentially from left to right; each of the first reaction tank, the second reaction tank and the third reaction tank comprises a heat insulation layer, a gravel packing layer, a mud-free grit packing layer, a zeolite base material layer, a coal ash base material layer, lower partition plates, an anti-permeation membrane and upper partition plates. The artificial wetland sewage treatment system has advantages that quick discharging of precipitates and segmental combined treatment can be realized, and excellent nitrogen and phosphorus removal effects areachieved.

The invention discloses a bioretention system suitable for processing urban initial rainwater in a severe nitrogen pollution area. The system is composed of a water inlet facility, an overflow facility, plants, a filler layer, an internal water level regulating and controlling facility and a water discharging facility; the water inlet facility intercepts runoff with extremely poor water quality inthe initial stage of rainfall through a surface-layer water inlet pipe; the overflow facility includes an overflow weir and an overflow pipe; the plants are planted at the surface of the filler layer, and a planting mode of the plants is optimized according to the nitrogen removing characteristics of the plants; the filler layer realizes high-efficiency nitrogen removal through addition of a novel nitrogen-removing material; the water discharging facility promotes infiltration, interception and discharge of rainfall runoff in the system by utilizing perforated water-discharging pipes arrangedat the bottom of the system; and the internal water level regulating and controlling facility is a U-shaped pipe, an internal water storage layer is formed in the water inlet process through a theoryof communicating vessels of the U-shaped pipe, a height of the U-shaped pipe can be adjusted to create the aerobic-anaerobic alternating environment required for the nitrogen removal, and the top ofthe U-shaped pipe is provided with a sensor to control water inflow to ensure effective storage and retention of the initial rainwater.

The invention provides a biodegradable foaming material and a preparation method thereof. The biodegradable foaming material is prepared from, by weight, 100 parts of biodegradable polymer A and a10-40 parts of biodegradable polymer B, the opening percentage of the foaming material is 50%-90%, and the specific surface area is 100-900 m<2> / g. The preparation method of the biodegradable foaming material is simple, and the biodegradable foaming material is stable in structure, high in porosity, large in specific surface area, high in mechanical strength and good in impact resistance property andcan serve as a carrier for water treatment. In addition, the biodegradable foaming material provides a solid carbon source for microbes, especially for denitrifying bacteria, the growth and nitrogen removal effects of the denitrifying bacteria are improved, and meanwhile secondary pollution due to increase of the organic content in water is not caused.

The invention discloses a microorganism carrier which comprises more than one biodegradation polymer resin porous layer A and more than one abiotic degradation resin porous layer B. The porous carriercan facilitate growth and reproduction of beneficial bacteria and can also keep shape integrity after biodegradation polymer resin is consumed, abiotic degradation resin in the porous carrier can still provide load capacity after the biodegradation polymer resin is consumed, additional space is generated as the biodegradation polymer resin is consumed, the load amount of the beneficial bacteria is increased, microorganism advantages are continuously achieved, and the microorganism carrier is easily recovered after being used.

The invention provides a method for denitrifying rare earth ore wastewater by using supported microalgae, and belongs to the technical field of wastewater treatment. The invention provides a method for denitrifying rare earth ore wastewater by using supported microalgae, which comprises the following steps: carrying out quicklime precipitation on rare earth ore wastewater raw water to obtain clarified water; and denitrifying the clarified water, wherein the denitrification is carried out under the condition that flocculation microalgae and corncobs exist at the same time. According to the method provided by the invention, rapid, effective and economic treatment of the high-ammonia-nitrogen rare earth ore wastewater is realized; the total nitrogen and ammonia nitrogen removal capacity is high, the average ammonia nitrogen removal capacity is 83.3 mg. L <-1 >. d <-1 >, the average total nitrogen removal capacity is 86.7 mg.L <-1 >. d <-1 >, and the method further has a series of advantages of being low in treatment cost, simple in process operation equipment, stable in effect, environmentally friendly, capable of achieving rare earth element recycling and algae colony recycling and the like.

The invention discloses a swage disposal system for a ship and a disposal method of the swage disposal system. The sewage disposal system for the ship comprises an oil water separator, a precise filter, an ultraviolet sterilizing device, a resin adsorption system, an MBR membrane bioreactor, a liquid buffer tank and a membrane separator. The disposal method for the swage disposal system for the ship comprises the following steps: (1) sewage flows into the oil water separator; (2) the sewage enters the precise filter from the oil water separator to be filtered; (3) water flowing out of the precise filter enters the ultraviolet sterilizing device; (4) water flowing out of the ultraviolet sterilizing device enters the MBR membrane bioreactor; (5) water flowing out of the MBR membrane bioreactor enters the liquid buffer tank; (6) water flowing out of the liquid buffer tank flows to the membrane separator; (7) water flowing out of the membrane separator enters the resin adsorption system. The sewage disposal system is simple in structure and good in purifying effect.

The invention relates to a method for efficiently treating high-ammonia nitrogen raw water at a low temperature, belonging to the technical field of water treatment. The invention solves the problems of low ammonia nitrogen treatment efficiency at low temperature and further influencing the water supply security in the conventional treatment method. When the high-ammonia nitrogen raw water flows through a biological nitration unit, the ammonia nitrogen is transformed into nitrate nitrogen and organic substances are removed; and the nitrate nitrogen is transformed into nitrogen gas and is removed thoroughly by a biological ceramic grain-sulphur-alkali filter bed. The biological ceramic grain-sulphur-alkali filter bed unit provided by the invention adopts gradation and mix of ceramic grains, sulphur grains and CaHCO3 (sodium bicarbonate) grains. The ceramic grains and sulphur grains provide growth environment for denitrifying bacteria, and CaHCO3 (sodium bicarbonate) adjusts alkalinity and provides inorganic carbon source. The removal rate of the nitrate nitrogen at low temperature keeps 98% and the removal rate of the ammonia nitrogen at low temperature keeps 95%; as calcium in the effluent water is used as flocculant for reinforcing removal of SS (suspended solid) and total phosphorus, the quality of the effluent water is further enhanced. The method provided by the invention effectively transforms ammonia nitrogen into nitrogen gas at low temperature, and is particularly suitable for use in winter and in cold regions.

The invention discloses a method for purifying low-carbon-nitrogen-ratio domestic sewage by a biological fermentation coupling artificial wetland system. The system consists of a microbial fermentation system and a wetland unit which are connected in series. The method comprises the following steps: fermenting straws by adopting microorganisms to obtain a microbial fermentation broth; then adding the microbial fermentation broth into the artificial wetland; mixing the microbial fermentation broth with domestic sewage to obtain a mixed solution, and treating the mixed solution by using the artificial wetland to obtain purified domestic sewage. According to the method, the straws are fermented, so that the straws are reasonably utilized; the resource utilization rate is increased; the carbon source release capacity is high; the carbon-nitrogen ratio of the sewage is effectively improved; and the sewage treatment efficiency is improved.

The invention discloses a preparation method for a graphene rare earth aluminum alloy high-conductivity material cable. Aluminum alloy is obtained by performing smelting on waste aluminum, silicon-calcium alloy, copper-aluminum alloy, zinc-aluminum alloy, magnesium ingot, rare earth aluminum alloy and graphene; and next, heat treatment is performed, and then the graphene rare earth aluminum alloy high-conductivity material cable is obtained by processing. According to the preparation method for the graphene rare earth aluminum alloy high-conductivity material cable provided by the invention, through reasonable setting of the technological parameters and optimization of the graphene structure, the overall performance of the aluminum alloy is improved effectively, so that the obtained graphene rare earth aluminum alloy high-conductivity material cable has the advantages of high intensity, plasticity, conductivity, heat resistance, resistance to fatigue under flexing, and processing performance and the like.

The invention discloses a titanium dioxide calcination exhaust gas comprehensive utilization system and an exhaust gas processing method, and relates to the field of titanium dioxide calcination exhaust gas recycling. The system comprises an exhaust gas purification device, a heat energy recovering device, a steam using device and a waste liquid recovering device, the exhaust gas purification device is in circulated connection with the heat energy recovering device, the heat energy recovering device is connected with the steam using device, and the waste liquid recovering device is connected with the exhaust gas purification device; the exhaust gas purification device comprises a dust removal device, a desulfurizer, a denitrification device, a demisting device, an induced draft fan and a chimney, and the heat energy recovering device comprises a primary heat energy recovering device, a secondary heat energy recovering device and a thrice heat energy recovering device which are sequentially connected; and the steam using device comprises a power generation system and a heat supply system. According to the titanium dioxide calcination exhaust gas comprehensive utilization system andthe exhaust gas processing method, while the environmental requirement is met, the calcination exhaust gas heat energy using rate is effectively improved, and the titanium dioxide calcination exhaustgas economical value is improved.

The invention relates to a city watercourse drain outlet sewage treatment method. The method mainly comprise the steps of regulation, wherein sewage is introduced into a regulating reservoir for regulation; mixing with flocculant, wherein sewage in the regulating reservoir is led out to be mixed with flocculant; flocculent settling, wherein sewage mixed with flocculant is sequentially introduced into a baffle flocculation reaction tank and a settling tank for sewage flocculation and sludge precipitation separation; denitrification, wherein water discharged from the settling tank and part of water discharged from a nitration aerating filter are introduced into a denitrification filter for denitrification; aerobiotic nitration, wherein water discharged from the denitrification filter is introduced into a nitration aerating filter for nitration; filtration, wherein part of water discharged from the nitration aerating filter is introduced into a filtering device for filtration. The invention further provides a sewage treatment device adopting the method. The sewage treatment device comprises a regulating reservoir, a pipeline mixer, a baffle flocculation reaction tank, an oblique plate settling tank, a denitrification filter, a nitration aerating filter and a clear water pond which are connected in series, wherein a water outlet pipeline of the clear water pond is connected to a filter device.

The invention discloses a synchronous short-cut nitrification-denitrification water treatment apparatus and a synchronous short-cut nitrification-denitrification water treatment process. The apparatuscomprises a water treatment bin cylinder and a central control system, wherein the water treatment bin cylinder comprises an inner ring layer and an outer ring layer, the inner ring layer is providedwith an internal aeration device and a three-phase separation zone, the outlet of the three-phase separation zone is connected to a reflux pipe, the reflux pipe extends into the outer ring layer, andthe inner ring layer is provided with a first through-wall pump. According to the process, sewage and active sludge are subjected to a nitrification reaction in the first aerobic zone of the inner ring layer; the mixture after the reaction enters the three-phase separation zone, wherein gas and part of the mud-water mixed liquid enter the outer ring layer through the reflux pipe, the remaining mud-water mixed liquid overflows upward, and the water is discharged after precipitation; and the mud-water mixed liquid refluxed to the outer ring layer is subjected to denitrification in the outer ring layer, and the obtained liquid enters the inner ring layer through the first through-wall pump, and is subjected to nitrification. According to the present invention, with the apparatus and the process, sewage can be subjected to synchronous short-cut nitrification and short-cut denitrification in the water treatment bin cylinder, such that the sewage nitrogen removal effect is good, the efficiency is high, and the oxygen consumption and the active sludge consumption required in the process are reduced.

The invention discloses a method and a system for deeply removing total nitrogen in sewage, and relates to the technical field of sewage treatment. The method comprises the following steps: adding a carbon source into sewage containing NO3 <-> and NH4 < + >, wherein the concentration ratio of COD to nitrate nitrogen in the sewage is (2.7-3.5): 1; enabling the sewage carrying the carbon source toenter a reactor with a suspended sludge layer, penetrate through the suspended sludge layer and enter an anaerobic environment containing anaerobic bacteria, wherein the concentration ratio of COD tonitrate nitrogen in the sewage is (1-1.5): 2; and finally discharging water. The method is good in deep decarburization effect, and the process for realizing deep denitrification is simple, easy to control and easy to transform. The system comprises the reactor with the suspended sludge layer and an anaerobic reaction unit, the reactor is communicated with the anaerobic reaction unit, the reactoris provided with a sewage inlet end for sewage to enter, and the anaerobic reaction unit is provided with a clear water outlet end; the system is simple in structure, easy to implement and suitable for upgrading and reconstructing an existing sewage treatment plant.

The invention relates to a technique for cultivating bulrush and removing total nitrogen in an artificial marsh of landfill leachate, which takes the bulrush as a marsh cultivated plant. The planting density of the bulrush is within 1000cm2 / plant, the treated landfill leachate is replenished every day, the COD concentration of the landfill leachate is controlled below 1000mg / L, the concentration of the total nitrogen is within 1000mg / L, and the bulrush is harvested at the end of August. The invention has the advantages that the absorbing capacity of the bulrush to the total nitrogen of the landfill leachate is closely related to the growth cycle, the planting density and the like, and an excellent denitrogenation effect is obtained by controlling the planting density and the clipping time; experiments prove that the highest nitrogen accumulation quantity of the parts of the stems and the leaves of the bulrush reaches 19.82g / m2 at the end of August, which shows that 3872.63g of total nitrogen can be removed from the marsh by the timely harvesting of the bulrush; and the nitrogen removal function of the artificial marsh of the landfill leachate can be best exerted by harvesting the bulrush at the end of August.

The invention discloses a sludge source reduction treatment method and a device. The method includes: subjecting a sludge and sewage mixed solution to complete aeration and mixing in an aerobic biochemical pool, introducing the effluent solution into a precipitation pool to undergo precipitation, bringing out the supernatant, and periodically extracting quantitative precipitated sludge from the precipitation pool, making the quantitative precipitated sludge enter a pre-anoxic reaction pool and then enter an anaerobic reactor through the pre-anoxic reaction pool to undergo reaction, then extracting equivalent sludge and leading it into a pre-aeration reaction pool to undergo aeration mixing for 2-8h, then extracting an equivalent sludge mixed solution from the pre-aeration reaction pool to supplement the aerobic biochemical pool, thus finishing cyclic exchange flow of the sludge among precipitation-pre-anoxic-anaerobic-pre-aeration-aerobic-precipitation equipment. The method and the device provided by the invention have the advantages that: the sludge reduction effect is good and stable, the nitrogen removal ability of the technological system is enhanced, and the newly added pre-aeration reaction pool strengthens the nitrification function of the system, so that more nitrogen pollutants are converted to nitrate nitrogen and then can be removed in the anaerobic reactor, construction and transformation are easy, and the building cost is low, thus having long-term economic benefits.

The invention provides a porous carrier which contains a biodegradable polymer resin A and a non-biodegradable polymer resin B, wherein the biodegradable polymer resin A and the non-biodegradable polymer resin B are continuous phases. The porous carrier disclosed by the invention can achieve the effects of promoting growth and propagation of beneficial bacteria and maintaining morphological integrity after the biodegradable polymer resin is consumed; after the biodegradable polymer resin is consumed, the non-biodegradable polymer resin in the porous carrier can still provide loading capacity,and since the biodegradable polymer resin is consumed to produce an extra space, the loading capacity of the beneficial bacteria is expanded, beneficial effects of microbes are continuously achieved,and the carrier is easy to recover after being used up.

The invention discloses a resource utilization method of aquaculture waste. A microporous aerator BioMat and an air-pushed hydraulic stirring shore circulating water pump AirLD are adopted to ensure high dissolved oxygen of 5 mg / L and water circulation of a water body, sucrose is used as a carbon source, the carbon-nitrogen ratio C / N is regulated to be 15, and a basic biofloc culture water body suitable for growth of cultured animals is cultured; commercialized bacillus South Ranch compound bacillus raw powder on the market is purchased, the bacillus South Ranch compound bacillus raw powder issoaked in 10 kg of normal-temperature water for 4 h according to the dosage for per 500 g and then splashed to a whole pond, the available water surface is 20 mu, the bacillus South Ranch compound bacillus raw powder is fed into a water body every week, and production of PHB in the water body is promoted.

The invention relates to the field of ecological restoration, in particular to an ecological method for treating nitrogen pollution under different habitats by utilizing an amphibious plant alternanthera philoxeroides. The method comprises the following steps: selecting three nitrogen-polluted habitats, comprising a terrestrial habitat, an aquatic habitat and an amphibious interactive habitat, forplanting alternanthera philoxeroides, limiting conditions such as planting line spacing and the like, and harvesting the plant at regular intervals. The invention solves the problem of nitrogen pollution under different habitats by the ecological method; according to the method, by planting the alternanthera philoxeroides with amphibious habits, vegetative propagation can be achieved through cuttage, the nitrogen absorption capacity is high, and nitrogen pollution conditions under different habitat conditions can be treated; due to the characteristic that the alternanthera philoxeroides growsrapidly through habits such as cloning and integration, the alternanthera philoxeroides can be harvested for multiple times in one year, and rapid reduction of the nitrogen level of soil and purification of water eutrophication are facilitated.

Disclosed is a biochemical method for treating synthetic leather wastewater comprising dimethylformamide. The present invention relates to the field of wastewater treatment. The biochemical method comprises the following steps: introducing to-be-treated synthetic leather wastewater into a new membrane bioreactor with an aerobic sludge-anaerobic packing structure, the new membrane bioreactor comprising an aerobic zone and an anaerobic zone; firstly enabling the to-be-treated synthetic leather wastewater to enter the aerobic zone in which specifically domesticated activated sludge with nitrifying bacteria as a dominant bacterial community is used, controlling the sludge return ratio of the aerobic zone to 100 to 300%, and adjusting the pH value of the aerobic zone to 8 to 9; enabling the synthetic leather wastewater treated in the aerobic zone to enter the anaerobic zone which is filled with a suspended filler and has a volumetric ratio of 30 to 60%; and discharging the synthetic leather wastewater treated in the anaerobic zone from the new membrane bioreactor with the aerobic sludge-anaerobic packing structure. By using the method of the present invention, the ammonia nitrogen and total nitrogen of outflow water can stably reach the Discharge Standard of Synthetic Leather and Artificial Leather Industrial Pollutants (GB21902-2008).

The invention discloses a method for preparing magnetic biomass charcoal from potamogeton crispus and application thereof. The method comprises the following steps: 1, cleaning, drying and smashing potamogeton crispus and putting into a crucible, compacting potamogeton crispus powder to fill the crucible, covering the crucible with a crucible cover, and then using aluminum-foil paper for wrappingand sealing the crucible; putting the wrapped crucible into a muffle furnace, carrying out constant-temperature pyrolysis at 300-500 DEG C for 1 hour, and carrying out post-treatment to obtain potamogeton crispus biomass charcoal; 2, putting the potamogeton crispus biomass charcoal into a suction flask, connecting one end of the potamogeton crispus biomass charcoal into a vacuum pump, connecting the other end of the potamogeton crispus biomass charcoal into a beaker filled with a Fe < 3 + > solution, starting a vacuum pump to pump out air in pores of potamogeton crispus biomass charcoal powder, and closing the vacuum pump to suck the Fe < 3 + > solution into the suction flask; transferring the mixture in the suction flask into a three-neck flask, and adding a Fe < 2 + > solution; and carrying out constant-temperature magnetic stirring under a nitrogen condition, dropwise adding an alkaline solution until the pH value is equal to 10-11, and reacting to obtain the magnetic potamogeton crispus biomass charcoal. The method has the advantages of energy conservation, environmental protection, better environmental benefit and economic benefit and the like.

The invention discloses an ultrasonic nitrogen removal apparatus for sewage. The ultrasonic nitrogen removal apparatus comprises a reaction device and a feeding device arranged on the upper part of the reaction device, wherein the reaction device comprises a first shell, a second shell and a third shell sequentially arranged from interior to exterior; an ultrasonic oscillator is arranged on the bottom of the first shell; a feeding pipe and a probe are arranged on the top of the first shell; the feeding device comprises a water distributor, a waste water pipe and a chemical feeding pipe; the waste water pipe and the chemical feeding pipe are respectively provided with a first a solenoid valve and a second solenoid valve; the probe is provided with a pH detector; the bottoms of the first shell and the third shell are respectively provided with a first drain pipe and a second drain pipe; a filtering assembly is arranged between the second shell and the third shell; a liquid pump is arranged in the second shell and connected with a third drain pipe; and a controller is arranged on the second shell. The ultrasonic nitrogen removal apparatus for sewage in the invention can effectively solve the problems of large size, complicated structure and poor nitrogen removal effect of conventional apparatuses.

The invention provides a device, which uses processing soil layers and penetrating filter medium layers to purify river water, and a method thereof. The river water purifying device comprises alternatively stacked processing soil layers and penetrating filter medium layers Each processing soil layer comprises a plurality of isolated unit soil layers. A predetermined amount of river water is stored, the river water is supplied to a storing part, which is arranged in the upper end of a nitric acid soil layer, in each soil layer; each penetrating filter medium layer has a stronger hydraulic conductivity, compared with the processing soil layers; the river water purifying device has the advantages that the amount of processed river water is increased; anaerobic conditions are formed stably inspite of the water penetrating coefficient of the soil; and nitrogen, phosphor, and nutritive salt s are removed effectively.

The invention relates to the technical field of domestic sewage treatment, in particular to a preparation method and application of an efficient nitrogen removal agent for rural domestic sewage treatment. According to the technical scheme, the nitrogen removal device comprises a reaction kettle and a nitrogen removal agent, wherein the nitrogen removal agent comprises calcium hypochlorite, calcium chloride, polyethylene glycol, sodium carboxymethyl cellulose, potassium phosphate, activated carbon, an additive and water; the additive comprises magnesium oxide, sodium chloride, nitric acid and deionized water; the preparation method comprises the following steps: sequentially adding certain amounts of calcium hypochlorite, calcium chloride, sodium carboxymethyl cellulose, potassium phosphate and activated carbon into a reaction kettle, sequentially adding polyethylene glycol and water into the reaction kettle, and finally adding an additive. The method has the advantages of no increase of condensed by-products during nitrogen removal and better nitrogen removal effect.