596 results about "Sulphate reduction" patented technology

An apparatus and method produces nitrate ions on-site from water, natural gas and air extracted in proximity to the apparatus. The apparatus generates nitrate ions and brings the nitrate ions into contact with an aqueous system. Hydrogen sulfide present in the aqueous system is removed and the production of hydrogen sulfide by sulfate-reducing bacteria (SRB) is eliminated by introducing into the system nitrate ions, whereby denitrifying microorganisms, using nitrate, outcompete the sulfate-reducing bacteria for the available carbon nutrients, thus preventing the SRB from producing hydrogen sulfide. Nitrate ions generated by the apparatus and added to the aqueous system which contains the denitrifying microorganisms can enhance oil recovery by means of microbial enhanced oil recovery mechanisms.

A method of repairing mine ecological environment comprises the treatment of mine environment contamination, wherein the tailings, the barren rock, the smelting slag, the waste water from ore cleaning, the waste water from smelting, the acid mine drainage and the ore yard leachwater which are generated from mine development are collected into the tailings storage, at the same time, sludge and organic matter capable of being degradated by microbiology are added therein, and then the tailings storage is given an anaerobic environment artificially, so that, under the action of microbiology and sulfate reducing bacteria, sulfur ion is generated and the pH value of the tailings storage is increased, a plurality of heavy metal ions are cured and settled by sulfur ion to avoid migration, a biomembrane layer-sulfate reducing bacteria reducing-induction biomineralization precipitation composite geochemical barrier is generated in the tailings storage. The repairing of mine ecological environment is realized by the treatment of mine environment contamination. The present invention can be used for tailings storage pollution prevention in tour, and can be used for closing the repairing of mine ecological environment, or can be used for designing new tailings storage by using the technology of the present invention.

The invention provides a bioremediation composition for in situ bioremediation of soil and/or groundwater contaminated with hydrocarbons, comprising an adsorbent capable of adsorbing said hydrocarbons, a mixture of facultative anaerobes capable of metabolizing said hydrocarbon under sulfate-reduction conditions, a sulfate-containing compound that releases sulfate over a period of time, and a nutrient system for promoting growth of said anaerobes, wherein said nutrient system includes a sulfide scavenging agent.

The invention discloses a method for treating acidic waste water containing heavy metal and reclaiming the heavy metal through a biomass fixed bed, which is characterized in that dry solid biomass capable of being decomposed by microbes is granulated and filled into a container with a supporting layer and a water distributing device so as to form a fixed bed microbe reactor; sewage disposal plant sludge containing sulfate reducing bacteria is taken as the source of microbe bacteria on the fixed bed, and the microbes are cultured, proliferated and acclimated to adapt to the environment of the biomass filler fixed bed through the backflow circulation of the outputted water or taking ferrous sulfate aqueous solution as the inputted water; acid effluent containing heavy metallic ions is led into the fixed bed for direct filtration; and when the water filtering speed can not meet the preset requirements, the operation is stopped, substances in the fixed bed are taken out, the heavy metal is reclaimed through smelting, and the fixed bed microbe reactor is refilled. The method is suitable for waste water containing Cr2O7 <2->, AsO3 <2->, Cu <2+>, Hg <2+> Ag <+>, Cd <2+> and the like. The method can be used for reclaiming the valuable metal resources with low waste water treatment cost.

The invention discloses a bacterial strain b capable of resisting the growth of heavy metal Cd and reducing sulfate, and a bacterial strain capable of resisting the growth of the heavy metal Cd and solubilizing phosphate. The classification and name of the bacterial strain b and the bacterial strain are respectively enterbacter ludwigii SRB-2-5U-2 and pseudochrobactrum saccharolyticum LB-4-4-1c, which are already preserved in the Common Microbe Center of the China Committee for Culture Collection of Microorganisms. The bacterial strains disclosed by the invention can be used for simultaneously remediating the surface soil, deep soil and rhizosphere soil of a plant, reducing the pollution of Cd to surface water and underground water, and also improving the activity and fertility of the soil.

The present invention belongs to the smoke purification technical field, and discloses a method for deoxidizing integrating, complexing and absorbing the organism and removing SO2 and No in the smoke, which is characterized in that alkaline absorption solution containing the ferrous-iron complexing agent Fe<II>(L) is arranged inside an absorption tower; SO2 is neutralized in the absorption solution, and NO is absorbed by the complexing iron; the smoke is exhausted from the top of the absorption tower; the absorption tail solution enters into an anaerobic reactor, and SO3<2> or SO4<2> in the tail solution is deoxidized to sulfide by sulfate reducting bacteria; the sulfide deoxidizes Fe<II>(L)-NO, Fe<III>(L) and other N-S compound in the tail solution to Fe<II>(L) and N2; at the same time, the sulfide is oxidized to simple sulfur; the absorption tail solution containing the Fe<II>(L) is directly returned to the smoke absorption tower to be used as desulphurization denitration absorption solution. The method of the present invention has the advantages that the micro-organism smoke desulphurization method and the complexing absorption smoke denitration method are combined, so that the sulfur dioxide and the nitrogen oxide can be synchronically removed, and the sulfur resource can be recycled; the complexing iron absorption agent can be cycled for use.

The present invention belongs to the waste water treating technology utilizing sulfate reducing bacteria. Upwards flowing anaerobic composite bed bioreactor and mixed sulfate reducing bacteria are used in treating acid waste water containing Cr2O72-, CrO42-, Cu2+, Zn 2+, Mn2+ and other heavy metal ions. The present invention has high activity of sulfate reducing bacteria and high waste water treating efficiency. The present invention features that inside the reactor or waste water tank, simple substance iron is added to result in waste water pH value of 5.5-8.5, and that the biochemical reaction is performed at 25-30 deg.c. The present invention has the advantages of addition of simple substance iron, raised waste water pH value, improved bacteria living environment, high metabolic activity of the bacteria, reinforced capacity of the sulfate reducing bacteria, raised bacteria adaptability and waste water treating capacity.

The invention relates the microorganism agent used to control oil field sulfate-reducing bacteria and its application. The invention can used to control oil field secondary depletion sulfate-reducing bacteria and microorganism. The water outlet system of secondary depletion technology comprises sulfate-reducing bacteria, H2S and sulphide, which can cause corrosion and pollution of sulphide. Microorganism agent comprises denitrifying bacteria culture, nutrescin and synergic nutrescin. 0.01-1wt% denitrifying bacteria culture, 5-100g/L culture and 10-200ppm synergic nutrescin. Microorganism agent can avoid SRB growing, SRB producing H2S, and removing sulphide. At the same time, metabolite can improve recovery efficiency.

The invention belongs to the technical field of waste water treatment and relates to a process method for conducting removal treatment on waste water containing carbon, nitrogen and sulfur, in particular to a method for removing the carbon, the nitrogen and the sulfur in the waste water. The method comprises five processing steps of oxidation treatment, neutralization sediment, sulfate reduction,methane generation and deep treatment by a sequencing batch reactor. Firstly ferrite and hydrogen peroxide are added in the waste water to conduct redox to obtain first-class effluent after being mixed, then alkali is added to conduct coagulating sedimentation to remove organic matters to obtain second-class effluent, a two-phase anaerobic process is introduced to conduct sulfate reductive treatment, methane generation treatment is carried out to obtain energy methane raw materials and fourth-class effluent, and finally the deep treatment is carried out on the fourth-class effluent by using the sequencing batch reactor, and purified effluent is obtained through treatments of an aerobic process and an anaerobic process. The method is strong in practical applicability, safe and stable in operation and good in treatment effect, chemical oxygen demand and removal rates of ammonia nitrogen and sulfate are more than 95%, and the effluent quality reaches the standard.

The invention relates to a preparation method and application of nutrient source immobilized sulfate reducing bacterium globules. Immobilized globules take polyvinyl alcohol and sodium alginate as carriers, a saturated boric acid calcium chloride solution as a cross-linking agent and sodium lactate as a nutrient source. The preparation method comprises the specific steps: firstly, dissolving the polyvinyl alcohol and the sodium alginate in a water bath at a constant temperature; then, adding active carbon, calcium carbonate, silicon dioxide and free bacterium liquid; sucking a mixed solution by an injector and dropwise adding the mixed solution into the saturated boric acid calcium chloride solution; crossly linking for 24h to form the globules; washing the globules with sterile physiological saline and putting the globules into a sodium lactate solution for 24h; after washing, freezing and drying to obtain the nutrient source immobilized sulfate reducing bacterium globules. In the application of the nutrient source immobilized sulfate reducing bacterium globules prepared by the invention, the nutrient source immobilized sulfate reducing bacterium globules have a good removing effect on four types of heavy metal including Cu, Zn, Pb and Cd in sediment of Xiang River; the treatment is stable and the leaching rate is low. The material is convenient to separate, can be repeatedly utilized and does not cause secondary pollution; the nutrient source immobilized sulfate reducing bacterium globules has good economic benefits and a wide application prospect.

The invention provides a process for treating acid wastewater in a mine and reclaiming valuable metals in the wastewater. The process comprises the following steps: (1) introducing the acid wastewater to a plurality of contact reactors in sequence and subsequently to a sulfate-reducing bioreactor; (2) through the control of return flow rate of a post-stage reactor, realizing the operation of each contact reactor in different pH, precipitating different metals; and (3) adopting food processing wastewater with the COD concentration of between 10,000mg/L and 100,000mg/L as a carbon source, and introducing the food processing wastewater to the sulfate-reducing bioreactor. In the process, the Cu2+removing rate in the acid wastewater of the mine reaches 99 percent, the Fe2+removing rate reaches 95 percent, the Fe3+removing rate reaches 90 percent, the pH of the processed wastewater is neutral, and the wastewater reaches the standard and can be discharged. The process has the advantages of utilizing the organic wastewater with the COD concentration of between 10,000mg/L and 100,000mg/L as the carbon source to reduce the cost of the carbon source, utilizing the design of phase splitting to reduce the inhibition of metallic ions to the wastewater, adopting return flow to reduce the inhibition of S2-ions to bacteria, and controlling the return flow rate to realize the selective precipitation of various valuable metals of the wastewater in each contact reactor on. The whole process can reduce the operating cost by 30 to 50 percent.

The invention discloses an oil field sewage bactericide and a preparation method thereof, belonging to the technical field of chemical agents for oil fields and preparation thereof. The oil field sewage bactericide is prepared by mixing the following components in percentage by mass: 10-15% of nano titanium dioxide powder, 0.5-2% of crosslinking agent, 5-10% of surfactant, 5-10% of oxidizer and the balance of water. The bactericide can be deposited on pipe walls, bent angles and other parts along with a liquid flow; a main agent can be slowly diluted out, has persistent chemical action and causes no corrosion to pipelines; the comprehensive sterilizing rate of the bactericide with respect to sulfate reducing bacteria, saprophytic bacteria and iron bacteria can be still up to 90% or above 18 days after filling; and the filling period of the chemical agent is 15-25 days which is 10-15 times longer in comparison with a common chemical agent, thereby greatly relieving the operation intensity and lowering the cost.