218 results about "Nitrate reducing" patented technology

The process for treating an ammonium containing liquid by denitrification treatment of an ammonium containing liquid containing at least ammonium comprises carrying out nitrate reduction treatment of reducing nitrate contained in or added to the ammonium containing liquid to nitrite, and carrying out anaerobic ammonium oxidation treatment of simultaneously anaerobically denitrifying nitrite produced in the nitrate reduction treatment and ammonium contained in the ammonium containing liquid by anaerobic ammonium oxidizing bacteria.

A nitrate reduction device has a cadmium structure forming a plurality of longitudinal channels within a flow chamber, which may be formed by a plurality of wires. The device is used to reduce nitrate to a final nitrite product for analysis.

A test paper for fast measuring out nitrate and nitrite is composed of colour display test paper soaked with mixture in the same volume of diazotization reagent and coupling reagent, and reaction test paper coated with nitrate reducer, the test paper can provide quick detection of nitrate and nitrite contained in food or vegetables.

The invention relates to a green composite additive for sauced beef, which is characterized in that the green composite additive is prepared by a composite curing agent and a composite spraying agent, wherein the composite curing agent contains 0.6 to 1.2 weight portions of celery powder, 0 to 0.4 weight portion of spinach powder, 0.08 to 0.15 weight portion of nitrate reducing bacteria and 0.08 to 0.015 weight portion of abnormal VC sodium; and the composite spraying agent contains 0.05 to 0.15 percent of tea polyphenol and 0.7 to 2 percent of sodium lactate aqueous solution. The composite additive is nutritious, healthy and widely applied, and not only can be applied to the sauced beef but also can be applied to meat products such as smoked sausages, smoked hams, fermented sausages, and so on. Moreover, the green composite additive accords with the requirements of consumers on safe and green foodstuffs, has larger realistic meaning in industrial production, provides a novel concept for production of the green meat products, and simultaneously creates good economic benefit for enterprises.

The invention relates to a method of using native function microflora to in-situ purify ground water polluted by uranium. The method translates transferable hexavalent uranium into nontransferable uranous uranium in the ground water through nitrate reducing bacteria flora, ferric iron reducing bacteria flora and sulfate reducing bacteria flora which are formed under the anaerobic condition by microorganism, and therefore the purpose of purifying the ground water polluted by the uranium is achieved. The specific implementation method comprises: (1) adjusting a potential of hydrogen (Ph) value of the ground water polluted by the uranium; (2) activating the microorganism in sediments; (3) regulating and controlling variation of the microflora, accelerating evolution of the nitrate reducing bacteria flora, the ferric iron reducing bacteria flora and the sulfate reducing bacteria flora by means of adding a carbon source, regulating oxidation reduction potential of the water polluted by the uranium and the like; (4) continuously regulating and controlling the microbial flora until uranium concentration in the ground water polluted by the uranium is reduced below the national emission standard and the purpose of purifying the groundwater polluted by the uranium is achieved. The method of using the native function microflora to in-situ purify the ground water polluted by the uranium solves in-situ purifying problem of the ground water polluted by the uranium, and has the advantages of being high in purifying efficient, short in period, simple in equipment, short in process procedure, low in purifying cost, strong in operability, free of secondary pollution, good in purifying effect and the like.

A method of removing nitrates from water by utilization of a zero-valent iron/oxidizing agent/zeolite synergetic system is provided. The zero-valent iron is common iron powder. The oxidizing agent is a common oxidizing agent used in water treatment. The zeolite is natural zeolite or artificial zeolite. The method is characterized in that: the oxidizing agent in the system oxidizes and strips a passivation layer formed on the surface of the zero-valent iron to allow electrons in the zero-valent iron to be transferred continuously to the outside, so that the zero-valent iron maintains high reduction activity to reduce the nitrates into ammonia nitrogen. Then efficient selective absorption of the zeolite to the ammonia nitrogen is utilized to remove the ammonia nitrogen in the water body. The method is environmental friendly, simple, feasible, low in cost, and capable of being efficiently used for treatment of waste water containing nitrates of industrial enterprises and nitrate restoration and removal for underground water.

A system and method using superheated steam optionally augmented by oxygen for the reduction of nitrogen oxides present for reducing nitrogen oxides present in a wide variety of organic compounds. The system includes a single reaction vessel, or optionally, multiple reaction vessels in operational communication. Reduction takes place quickly when a steam/oxygen mixture is injected into the reaction vessel or vessels. Reducing additives are metered into the reaction vessel or vessels and/or provide energy input to reduce nitrates to nitrogen. The oxygen, when used, allows for some oxidation of waste by-products and provides an additional offset for thermal requirements of operation.

The invention provides a method and process for synchronously removing perchlorate and nitrate in drinking water. In the method, perchlorate and nitrate in water are synchronously reduced through sulfur autotrophy and electrochemical hydrogen autotrophy coupling. The wastewater containing perchlorate and nitrate goes through a bio-membrane reactor taking sulfur particles as filler, and perchlorate and nitrate are partially reduced into chloride ions and nitrogen by taking elemental sulfur as an electron donor while H<+> and SO4<2-> are generated. A complex three-dimensional electrode-bio-membrane reactor taking a carbon medium as filler reduces H<+1> into H2 by use of an electrochemical process between a carbonaceous material and an electrode, and the rest perchlorate and nitrate are reduced into chloride ions and nitrogen by taking hydrogen as an electron donor. The method and process for synchronously removing perchlorate and nitrate in drinking water, provided by the invention, are economical and efficient and simple to operate.

An electrochemical method and system for removing nitrate and ammonia in effluents, using an undivided flow-through electrolyzer, said electrolyzer comprising at least one cell, each cell comprising at least one anode and one cathode, the cathode being in a copper/nickel based alloy of a high corrosion resistance and a high electroactivity for nitrate reduction to ammonia and the anode being a DSA electrode of a high corrosion resistance and a high electroactivity for ammonia oxidation to nitrogen in presence of chloride.

The invention discloses an anaerobic molysite biological nitrogen removal process which is characterized in that denitrifying bacterium enrichment culture is taken as a biocatalyst, under the anaerobic condition, nitrate is taken as an electron acceptor, ferrous salt is taken as an electron donor, the nitrate is reduced into N2 in the same reactor, and the ferrous salt is oxygenized into ferric iron, wherein the molar ratio of the nitrate to the ferrous salt is 1.0 to 5.0, the reaction temperature is 20 to 35 DEG C, the pH value is 7.0 to 9.0, and the hydraulic retention time is 0.5 to 2.0 d. The process has the following advantages: 1, ferrous salt is taken as the electron donor, nitrate is taken as the electron acceptor, and waste is treated with waste, so that the purposes of removing nitrate-nitrogen pollutant and utilizing ferrous salt waste can be achieved; 2, no organic matter is required, so that the problem that the carbon source is not enough relatively during waste water biological nitrogen removal can be relieved effectively; 3, ferric iron, which is a ferrous salt oxidation product and has high values, can be reclaimed; 4, the concentrations of nitrate and ferrous salt, which can be treated, can reach 1500 mgN/L and 30000 mgFe/L.

The present invention concerns the reduction of gastro-intestinal methanogenesis in ruminants with the aid of agents that compete for the hydrogen atoms required by methanogens during normal fermentation of ingested feed. The invention in one aspect resides in the findings that both nitrate reductive pathways as well as sulphate reductive pathways outcompete gastro-intestinal methanogenesis in ruminants and, that the methanogenesis reducing effects of nitrate and sulphate are completely additive. At the same time the combined administration of nitrate and sulphate was found to be fully effective to avoid or mitigate the potential problems of nitrite intoxication normally encountered when using nitrate alone, which effect is further enhanced, where necessary, by the addition of a nitrite reducing probiotic micoroorganism. Hence, products are provided comprising high amounts of a combination of a nitrate compound and a sulphate compound and optionally a nitrite reducing probiotic microorganism, as well as methods of reducing gastro-intestinal methanogenesis in ruminants using such compositions.

The invention discloses a permeable reactive barrier system and a method for in-situ remediation of petroleum hydrocarbon in groundwater by an enhanced anaerobic biotechnology, and belongs to the field of groundwater remediation. Groundwater containing the petroleum hydrocarbon flows through a permeable reactive barrier along the water flow direction, nitrate-reducing bacteria and sulfate-reducing bacteria formed by microorganisms under anaerobic conditions are utilized to degrade the petroleum hydrocarbon in groundwater, and accordingly the purpose of remediation of the petroleum hydrocarbon polluted groundwater is achieved. The permeable reactive barrier system and the method effectively solve the problems of low efficiency and high power consumption in a method for in-situ remediation of the petroleum hydrocarbon in the groundwater with the aid of indigenous microbial flora, and have the advantages of low acting time, high remediation efficiency, strong operability and good remediation effect.

The invention discloses streptococcus thermophilus separated from tibetan kefirs as well as a separation method and applications thereof, belonging to the field of microbial technology. The separation method is characterized in that an operation of streaking separation is performed on a M17 culture medium plate, an operation of culturing is performed 48 hours at a temperature of 42 DEG C, a bacterial colony is circular and raised, neat in edge and milk white in color, bacterial colonies which are non-transparent, contain spherical bacteria, can be subjected to wiredrawing, provided with wet and smooth surface, and mostly arranged in chains with different lengths are selected, and no spore is produced; the streptococcus thermophilus is negative in a catalase test, positive in gram stain, negative in a nitrate reduction test, and has no motility and aerobic and facultative anaerobic growth, gelatin is not liquefied, hydrogen sulfide is not produced, and the streptococcus thermophilus is negative in an indole test; the streptococcus thermophilus does not grow at a temperature of 15 DEG C; the growth temperature is 37-45 DEG C; the highest and lowest initial growth pH values are respectively 9.0 and 4.0, and the growth initial pH value is 6.5-7.0. The streptococcus thermophilus aas well as separation method and applications thereof disclosed by the invention have the beneficial effects that the maximum quantity of exopolysaccharides produced when the streptococcus thermophilus is fermented 30 hours by using a M17 culture solution under the condition of 42 DEG C is 111 mg/L; and when a fermented yoghurt is prepared by using strains provided by the invention, the amounts of a thickener and a stabilizer can be reduced.

The field of advanced wastewater treatment, and more specifically, to a natural pyrrhotite biofilter and a method for utilizing same to synchronously remove nitrate-nitrogen and phosphorus from water is provided. The method includes the following steps: (1) preparation of the packing material and construction of the biofilter; (2) start-up of the biofilter; (3) operation of the biofilter. The method disclosed in the present invention on the one hand takes pyrrhotite as the electron donor to help sulfur-based autotrophic denitrifying bacteria reduce nitrates into nitrogen gas, and on the other hand utilizes pyrrhotite and its oxidates to eliminate phosphorus through adsorption and chemical precipitation. Therefore, this method realizes synchronous removal of nitrate-nitrogen and phosphorus in water.

The invention discloses a high-bile salt resistance strain and bile salt hydrolase genes. The preservation number of the strain is CGMCCNo.8198. The strain has high acid resistance, high bile salt resistance, high nitrate reducing capability and the like. Three types of bile salt hydrolase genes of the strain are amplified, and are cloned, sequenced and heterogeneously expressed, so that generated bile salt hydrolases have high activity. The strain and the bile salt hydrolases can be used in the fields of food, medicine, agriculture and the like as food and feed leavening agents, microecological preparations, medicament expression carriers, feed additives and the like; the bile salt hydrolases can be developed into recombinant protein products, and can also be used for the molecular modification of lactic acid bacteria strains as selection markers of lactic acid bacteria gene engineering expression systems.

The invention discloses a special filler for nitrate nitrogen removal using a sulfur-iron coupling technology, and a preparation method thereof. The filler comprises, by mass, 40-60% of elemental sulfur, 10-15% of limestone, 15-25% of pyrite and 30-40% of denitrifying bacteria immobilized particles. Autotrophic denitrifying bacteria utilize the limestone to synthesize cells, the pyrite is used asan electron donor for nitrate reduction to complete the denitrification process, the denitrifying bacteria immobilized particles provide denitrifying bacteria to complete removal of nitrogen from thewastewater, and all the above components are designed to be granular to make the filler sufficiently stirred in order to ensure the full utilization of the filler.

The bacterium agent in this invention is used to biologically strenghen dephosphor- ization process in urban sewage treatment plant. It has mainly two uses: quickly start the biodephosphorization ability of new sewage treatment plant; resume the strong biodephosphorization ability of exasperate dephosphorization system. It is made from high efficient ployphospher bacterial strain GM6, and it is odor Pseudomonas putida from appraising result. Its main biocharacteristic is G-. Its thalli is rhabditiform with the size of 0. 7í‡2. 5ª–m, and it is facultative anaero-bic; it is positive in indole reaction, oxidase and sulfate reduction reaction; while negative in methyl red test, V-P reaction, citrate test and hydrogen sulfide reaction; the number of the strain 16S rDNA is DQ133506. The strain can be used to sewage dephosphorization.

The invention discloses an assimilation nitrate reductase gene and an assimilation nitrite reductase gene both extracted from bacillus megaterium as well as applications of the assimilation nitrate reductase gene and the assimilation nitrite reductase gene, and relates to the field of the biotechnology. The assimilation nitrate reductase gene is catalytic subunit nasC (Seq ID No.1) which codes assimilation nitrate reductase Nas; the assimilation nitrite reductase gene is large subunit nasD (Seq ID No.2) which codes assimilation nitrite reductase NiR. According to the invention, total RNA is extracted from the bacillus megaterium NCT-2, then cDNA synthesis is conducted to obtain a cDNA template, and function representation is realized through fluorogenic quantitative PCR. The assimilation nitrate reductase gene and the nitrite reductase gene can be further applied to research on removal of overmuch nitrate from soil.