8174results about "Contaminated soil reclamation" patented technology

A stable continuous method for producing ethanol from the anaerobic bacterial fermentation of a gaseous substrate containing at least one reducing gas involves culturing a fermentation bioreactor anaerobic, acetogenic bacteria in a liquid nutrient medium; supplying the gaseous substrate to the bioreactor; and manipulating the bacteria in the bioreactor by reducing the redox potential, or increasing the NAD(P)H TO NAD(P) ratio, in the fermentation broth after the bacteria achieves a steady state and stable cell concentration in the bioreactor. The free acetic acid concentration in the bioreactor is maintained at less than 5 g/L free acid. This method allows ethanol to be produced in the fermentation broth in the bioreactor at a productivity greater than 10 g/L per day. Both ethanol and acetate are produced in a ratio of ethanol to acetate ranging from 1:1 to 20:1.

Freeze wells may be used to isolate an area for soil remediation. Freeze wells may form a frozen barrier around a treatment area. The frozen barrier may inhibit fluid from entering into the treatment area. The frozen barrier may also inhibit migration of contamination out of the treatment area. The frozen barrier may be used to surround all of the perimeter of the treatment area. A frozen barrier may also be formed above or below a treatment area. Freeze wells may be activated in advance of soil remediation so that a frozen barrier is formed when soil remediation is begun. The soil remediation may be accomplished by any type of soil remediation system, including a thermal soil remediation system. Heaters of a thermal soil remediation system may be may be placed close to the frozen barrier without the barrier being broken through during remediation.

The invention discloses ion mineralization stabilizer for treating soil with heavy metal pollution and an application method thereof. The ion mineralization stabilizer comprises, by weight percent, 5-30% of sulfur-based compound, 10-50% of phosphor-based compound, 10-50% of calcium-based compound, and 10-30% of silicon-based compound. The materials are respectively ground into powders with particle size not less than 200 meshes, and the powders are proportionally mixed well. The application method of the ion mineralization stabilizer for treating soil with heavy metal pollution includes: detecting arsenic content and leaching toxicity of the soil to be treated, placing the ion mineralization stabilizers in different proportions on the surface of the soil to be treated according to pollution level, well mixing to form mixed soil by ploughing and stirring, adding water to keep the water content of the mixed soil no less than 25%, covering the mixed soil with moisturizing material, curing for at least 5 days to keep heavy metals in the mixed soil to form stable minerals.

A process for in-situ remediation of contaminated soil in which at least one treating agent is introduced into the contaminated soil and transported to an underground in-situ treatment zone of the contaminated soil by a foam-based fluid.

The invention provides a system for restoring organic contaminated soil through in-situ electrical heating. The system comprises an infrastructure technology, an electronic control system, a gas treatment system, a monitoring and data acquisition system and a repairing effect comprehensive assessment system. The infrastructure technology comprises heating well and extraction well construction, ground compaction and insulating layer construction technologies; heating wells are distributed on a contaminated site according to a triangle arrangement principle and a proximity principle, and the extraction well is arranged in the geometric center of the layout of the heating well; the gas treatment system is composed of a pre-cooling adsorption sledge, an extraction sledge and a treatment sledge, and is used for completing gas extraction and treatment and achieving the tail gas discharging requirement; and the repairing effect comprehensive assessment system evaluates the temperature risingeffect of the contaminated soil in the restoring process and the treatment effect of the contaminated soil. According to the system, the technological route is complete, the soil property applicability is wide, the heating temperature can reach 500 DEG C or above, and volatile and difficult-to-volatilize organic contaminant can be treated at the same time.

The invention provides a method for ecological remediation on an acid tailing pond. By removing acids from soil, and by laying nonwoven cloth and a sealing layer, good partitioning is achieved, and byfurther laying a water reservation layer and a coated seed layer, the purpose of re-greening an acid tailing pond is achieved. The method has the beneficial effects that rainwater can be reserved tothe maximum extent, the sealing layer is capable of preventing the rainwater from infiltrating into tailings, the problems of underground water and ground water pollution can be substantially solved,the construction method is simple, and the construction cost is low; by using a seed coating technique, a set of rapid nursery stock breeding technique is formed, a stable ecological remediation system is cultured, the target of completely re-greening woody plants within 90 days is achieved, and environment problems of acid tailing ponds are solved for good.

Solutions containing microorganisms differing in characteristics from each other and living in symbiosis with each other and enzymes characterized by containing aerobic microorganisms, anaerobic microorganisms and at least one basidiomycete belonging to the family Pleurotaceae living in symbiosis, metabolites thereof and enzymes; carriers obtained by adsorbing the components of the above solutions onto finely ground carbonaceous materials; and porous materials obtained by adsorbing the components of the above solutions onto porous materials. Because of having various effects of absorbing, adsorbing and decomposing harmful matters, deodorizing, decolorizing, etc., these materials are applicable to various uses in the fields of agriculture and environment.

A system and process are provided for recovering and/or cleaning residual or waste petroleum products such as sludge accumulated within a storage tank or upon process equipment surfaces, or from inorganic materials such as sand or clay, and the like. The system and process include a negatively charged aqueous-based dispersion fluid, which is contacted with the petroleum product under controlled relatively high pressure and high shear conditions for fluidizing hydrocarbon molecules and for preventing such molecules from adherence to process equipment surfaces, or contaminants such as sand or clay. Additional mechanical separation as by subjecting the mixed petroleum product and dispersion fluid slurry to sonic vibration may also be employed. The thus-fluidized slurry of petroleum products, dispersion fluid, and inorganic materials can be separated by conventional techniques, as by settling and/or flotation, for further individual processing and/or re-use.

An isolated Bacillus amyloliquefaciens Ba-BPD1 having an Accession No. of DSM 21836 is provided. This novel strain has unique 16S ribosomal RNA sequenced as SEQ ID NO:1 and produces amylase, protease, cellulase and lipase, fibrinolytic enzyme to show their biodegradation capacities. Further, B. amyloliquefaciens Ba-BPD1 produces the antibiotic substances, such as iturin, fengycin and surfactin, and has antimicrobial capacity for inhibiting the fungal or bacterial growth. In conclusion, the novel strain of Bacillus amyloliquefaciens Ba-BPD1 and its products can be applied in agriculture, wastewater treatment, food industry and chemical industry.

The present invention provides novel methods for removal and disposal of ammonia from spent dialysate in a dialysis system. Ammonium ions present in spent dialysate are converted into gaseous ammonia by raising the pH of the spent dialysate solution in a first reactor. Gaseous ammonia diffuses through a semi-permeable hydrophobic membrane at the outlet of the first reactor and into a second reactor via a gas channel. The second reactor converts gaseous ammonia into an ammonium compound for easy disposal.

The present invention relates to an aqueous decontaminating composition comprising(A) an amount of H2O2 less than or equal to 60% by weight, based on the total weight of said composition;(B) an RCO3H/RCO2H mixture, where R is methyl or ethyl, as indicated above, said mixture being present in an amount such that the weight ratio of said mixture to the hydrogen peroxide is between 0.15/1 and 0.85/1;(C) a silver component as a source of Ag ions, selected from the group consisting of silver salts and complexes, said silver component being present in an amount such that the weight ratio of said silver component to the hydrogen peroxide is between 0.0005/1 and 0.015/1;(D) a stabilizer present in an amount such that the weight ratio of said stabilizer to the hydrogen peroxide is between 0.0005/1 and 0.025/1; andwater to make up to 100% by weight. It further relates to the method of preparation and to the use of said composition.

The invention discloses a method for biologically remediating a water body and soil comprehensively utilizing resources. The method comprises the steps: (1), determining main pollutants in a selected land area or water body area; (2), selecting to plant and/or cultivate fast-growing herbaceous plants, fast-growing alga, trees, bushes, fungi or microorganisms with high remediation efficiency in the selected land area or water body area; (3), harvesting or collecting the fast-growing herbaceous plants and the fast-growing alga after growing to reach a suitable height or size; (4), concentratedly processing the harvested or collected fast-growing herbaceous plants and the fast-growing alga, and comprehensively utilizing to prevent the pollutants from dispersing; (5), remediating an eutrophic water body by adopting an artificial floating island; (6), remediating a heavy metal polluted water body by confining floating plants; (7), repairing cadmium and zinc polluted soil by mixed-cropping festuca arundinacea and bluegrass; (8), remediating polycyclic aromatic hydrocarbons (PAHs) polluted soil by mixed-cropping alfalfa and italian ryegrass; and (9), extracting and recovering silver from silver-containing wastewater remediation plants.

Systems and methods are provided for converting organic waste materials from a municipal waste stream to useful products. Organic waste materials having a wide range of compositions such as, for example, yard waste, food waste, paper, and the organic fraction of municipal solid waste are converted into a uniform biomass that is suitable for conversion to useful products, such as fuels. Through the use of a biomixer and a hydropulper, as well as through sorting and screening, the organic waste materials are progressively reduced in size and cleaned of contamination. The resulting uniform biomass is suitable for anaerobic digestion to produce biogas and a residual solid that is suitable for producing a high quality compost.

A method of recovering hydrocarbons from hydrocarbonaceous materials can include forming a constructed permeability control infrastructure. This constructed infrastructure defines a substantially encapsulated volume. A comminuted hydrocarbonaceous material can be introduced into the control infrastructure to form a permeable body of hydrocarbonaceous material. The permeable body can be heated sufficient to remove hydrocarbons therefrom. During heating the hydrocarbonaceous material is substantially stationary as the constructed infrastructure is a fixed structure. Removed hydrocarbons can be collected for further processing, use in the process, and/or use as recovered.

The invention discloses a heavy metal absorbent and a preparation method and use thereof. The heavy metal absorbent is prepared by using an inorganic mineral modified by a surfactant as a carrier and loading organic complexing agent on the carrier, wherein the inorganic mineral is bentonite, kaolin, kieselguhr, zeolite, aluminum oxide or iron oxide; the surfactant is cationic surfactant or nonionic surfactant; and the organic complexing agent is a compound containing a sulfydryl and an amino. The heavy metal absorbent has the advantages of stable performance, environment friendliness, high absorption capacity, high selectivity, convenient post-recovery treatment and the like. The absorption capacities of cadmium, mercury lead and other heavy metals all exceed 100mg/g, and the heavy metal absorbent can achieve good treatment effect in treatment of water and soil environments polluted by heavy metals.

A method for treating particulate biodegradable organic waste includes sizing the waste and adding a base prior to introducing the waste to a thermal hydrolysis reactor and hydrolyzing the waste at a temperature of about 130° C. or greater and a pressure greater than the saturated water vapor pressure to produce a slurry including solubilized organic material and residual solids. The solubilized organic material is separated from the residual solids using a liquid/solid separator and the solubilized organics are subjected to anaerobic digestion to produce a methane gas. The base is preferably potassium hydroxide (KOH) at a concentration of about 1%. The method may further include preheating the particulate biodegradable organic waste with latent heat of the separated solubilized organic material prior to thermal hydrolysis.

The invention relates to a soil pollution thermal desorption restoration processing system, which belongs to a soil restoration processing system. The system comprises a feed system, a heat source system and a control system, and is characterized by further comprising a thermal desorption system and a tail gas processing device, wherein the thermal desorption system consists of a draught fan and a thermal extraction converter, and the tail gas processing device consists of a dust remover and an absorption tower. When the system is applied to processing polluted soil with main pollutants of volatile/semi-volatile organic compounds, compared with the like products in other countries, the equipment cost is only 1/3 to 1/5 of the same; the problem of secondary pollution probably brought about in the process of processing the polluted soil is thoroughly avoided; a temperature control system has better practicability; the running cost for each ton of the polluted soil is between 300 and 500 RMB, which is far low than the processing cost for hazardous landfilling and incineration of the polluted soil; and half of the purification effect of processing the polluted soil with the main pollutants of the volatile/semi-volatile organic compounds can reach between 70 and 80 percent.

The invention discloses a passivating agent for governing heavy metal contaminated soil and a preparation and use method of the passivating agent. The passivating agent comprises, in weight percent, 30%-50% of clay minerals, 10%-20% of phosphate, 10%-15% of reducing agents, 10%-15% of sulfide and 15%-20% of alkaline substances. The preparation method includes a step: mixing the clay minerals, the phosphate, the reducing agents, the sulfide and the alkaline substances to mix to obtain the passivating agent. The use method includes the steps: firstly, crushing the heavy metal contaminated soil; secondly, adding the passivating agent into the crushed heavy metal contaminated soil; thirdly, adding water into the crushed heavy metal contaminated soil added the passivating agent to uniformly mix, maintaining the uniformly mixed soil on site, and enabling the passivating agent and heavy metal in the soil to sufficiently react. The passivating agent can effectively meet the urgent requirements of current Chinese heavy metal contaminated soil for high stability, no secondary pollution, durable and stable effect and low cost.

The invention provides a farmland soil heavy metal pollution restoration method through coupling activating and passivating, belonging to the technical field of environmental technology. According to a technical scheme adopted by the invention, the farmland soil heavy metal pollution restoration method comprises the following steps: a step I, planting heavy metal hyper-accumulation plant, applying a heavy metal activator into the soil, collecting plant which is enriched with heavy metals; a step II, applying a heavy metal passivator into the soil, planting and harvesting crops with heavy metal content reaching the safety standard. By two different coupling technologies in the two government stages, on one hand, the concentration of heavy metals in the farmland soil is lowered with high efficiency, on the other hand, the farmland can be put into safety production as early as possible, so that the heavy metal pollution farmland soil restoration efficiency is improved generally, and the method can be applied to farmland soil with large-area heavy metal pollution.

The outside treating process of polluted soil includes the following steps: excavating the polluted soil, filling the soil inside the treating apparatus, pumping with vacuum pump to form certain vacuum degree in the pumping well while intruding fresh air into soil to promote the volatilization of pollutant and taking out the volatile. The soil may be also heated to speed the volatilization. The treating apparatus consists of exhaust well with exhaust pipeline, temperature controlling sensor and heater embedded into soil pipe. The treated soil may be re-filled or used in other site.

The invention relates to a roller-type reverse thermal desorption system for soil polluted by organic matters. The roller-type reverse thermal desorption system comprises a soil feeding system, wherein the soil feeding system and a heat source system are connected with a reverse thermal desorption system; the reverse thermal desorption system is connected with a dust removing system, a cooling system and an active carbon adsorption system in turn; and control ends of the soil feeding system, the heat source system, the reverse thermal desorption system, the dust removing system, the cooling system and the active carbon adsorption system are connected with a control system. In the roller-type reverse thermal desorption system, hot air is fed into a reverse thermal desorption roller by an ignition system, and polluted soil is fed into the reverse thermal desorption roller by a soil transferring device, wherein the hot air contacts the soil reversely, so that organic pollutants contained in the soil are heated and volatilized; the purified soil is used as backfill soil; and the volatilized tail gas is dedusted by a cyclone dust extractor and an adsorption dust extractor after passing through an induced draft fan, and the dedusted volatilized tail gas is absorbed by a honeycomb-shaped active carbon tower after passing through an atomization cooling tower and a dial plate cooling device, and finally is discharged by a tail gas exhaust device on the basis of meeting the national standard. Materials can be fed into the roller-type reverse thermal desorption system continuously and can be heated directly; and the hot air and the polluted soil are fully mixed, and the roller-type reverse thermal desorption system has high thermal desorption efficiency.

The invention discloses a restoration agent for lowering cadmium/lead effective state content in soil, which is composed of quicklime, calcium sulfate, wood charcoal, iron chloride and water, wherein the weight ratio of the quicklime, calcium sulfate, wood charcoal and iron chloride is (1-2):(1-2):(1-2):(0.5-1), and the water accounts for 30-45 wt% of the soil. The restoration agent can be used for treating heavily polluted soil; and common chemical passivators can only restore lightly polluted soil, and do not have obvious effect on heavy pollution. The restoration agent can be used for treating both acidic soil and neutral soil. The restoration agent has high remediation efficiency for cadmium polluted soil; the reaction mechanisms relate to chemical precipitation and physical adsorption; and when one action fails due to change of the outside conditions, the other action can perform the guarantee function. The restoration agent has certain control actions on the lead effective state content in the polluted soil.

The invention includes a method and apparatus for composting organic material and maintaining composting conditions within preselected limits. Composting according to the method can occur within a sealable container. Adjusting the composition of the organic material to within preselected limits converts the organic material to a compostable mixture. The composition is adjusted by amending the organic material and by mixing the amended organic material with a bulking agent and an inoculant. Incubating forms a composting mixture from the compostable mixture. The method includes the steps of monitoring and adjusting conditions of the composting mixture to maintain the conditions within preselected limits. The conditions of the composting mixture are adjusted by aerating the composting mixture or remixing the composting mixture. The remixed composting mixture is incubated to yield composted organic material.

The invention discloses an in-situ restoration method for heavy metal polluted soil, which comprises the following steps of: uniformly mixing submicron or nano iron, coal ash, a magnesium-containing preparation and bentonite in proportion by weight of (5-25): (40-50): (1-10): (15-50) to obtain a heavy metal polluted soil restoration agent, after applying the heavy metal polluted soil restoration agent on the surface of the heavy metal polluted soil at the thickness of 1-4cm, uniformly mixing a 20cm thick polluted soil surface layer with the applied restoration agent by plowing, and after 3-6 months, reducing heavy metals such as cadmium, chromium, mercury, lead, arsenic, nickel, zinc, copper, magnesium and vanadium in the heavy metal polluted soil into low-valence immobilized heavy metals to lose biological effectiveness and realize the in-situ restoration for the heavy metal polluted soil. However, the environmental quality of restored soil satisfies the requirements of second-level standard values in Environmental Quality Standards for Soils (GB 15618-1995) in China.

The invention discloses a method for treating contaminated soil by combining in-situ heat strengthening and a soil vapor extraction technology, which is characterized in that a heating well with a certain form is formed in a contaminated area, a heater part is provided in the heating well, and a sleeve pipe is installed, a catalyst is filled in the sleeve pipe for accelerating the high temperature decomposition of the pollutant into simple micromolecular substances. At least one well bore is drilled at the central contaminated area of the heating well which is arranged in the certain form to form an extraction well, a vacuum system is provided for realizing the extraction of the contaminated tail gas. the heating well provides heat to contaminated soil of the heating well and the adjacent areas through the thermal conductivity of the heater part arranged in the heating well, soil is heated, the soil pollutant is subjected to processes of evaporation, in-situ pyrolysis, oxidation, combustion, distillation and the like to form tail gas like simple micromolecular gas, water and pollutant steam, then the tail gas is extracted by the vacuum system in the extraction well, and is connected to a tail gas collection pipeline of the extraction well to send to the ground surface, the pollutant in tail gas is treated through a pollutant treatment facility which is installed on the ground surface. The method also comprises an impervious sealing plate which is arranged on the contaminated soil area ground surface for minimizing the gas exchange of the heating well, the extraction well and atmosphere, and preventing the pollutant from entering in atmosphere to form secondary pollution, and a thermal insulation layer is arranged above or below the impervious sealing plate for avoiding the dissipation of heat.

The invention discloses slow-release fertilizer with the effect of soil remediation, which is prepared by polyhydroxyalkanoates which can be completely biodegraded, organic and inorganic nutrients and other substances, by slow-releasing the organic and inorganic nutrients, microorganism propagation and sustained and rapid growth of plants can be promoted, the bioactivity and water solubility of polycyclic aromatic hydrocarbons are quickened, and simultaneously, the defects of fertilizer loss and repeated fertilization can be avoided, thereby saving the cost and enhancing the soil remediation efficiency. The invention also discloses a soil pollution remediation method by utilizing the slow-release fertilizer, plants with the remediation effect are planted in the soil with the slow-release fertilizer, and efficient, environment-friendly and sustained remediation of the soil polluted by the polycyclic aromatic hydrocarbons (PAHs) can be realized by utilizing the microorganism-plant remediation technology.

A method for preparing highly stabilized and dispersible zero valent iron nanoparticles and using the nanoparticles as a remediation technology against inorganic chemical toxins in contaminated sites. The method employs a composition containing select polysaccharides (starch or cellulose) as a stabilizer for the iron nanoparticles in a liquid carrier, and results in suspensions of iron nanoparticles of desired size and mobility in water, brine, soils or sediments. The stabilizer facilitates controlling the dispersibility of the iron nanoparticles in the liquid carrier. An effective amount of the composition is delivered to a contaminated site so that the zero valent iron nanoparticles can remediate one or more toxins such as an arsenate, a nitrate, a chromate, or a perchlorate in the contaminated site.

The invention relates to a method for remediation of heavy metals contaminated soil by a plant-microorganism joint direction method. The detailed steps of the method of the invention are that: firstly, resistant bacteria of plant and microorganism is sifted, so as to obtain plant and microorganism bacteria strains with heavy metal resistance; and then the seeds of the resistant plant is soaked and coated in microorganism resistant bacteria solution; finally, the seeds are planted in the soil contaminated by heavy metal, therefore the soil can be remedied. The method has the advantages of good remediation effect, low cost, easy management and operation, no secondary pollution and broad application prospect, therefore, the method is the most important development direction of soil remediation technique.

The invention discloses a stabilized curing agent for heavy metal contaminated soil or solid waste treatment and a treatment method. The stabilized curing agent comprises the following components in parts by weight: 5 to 10 parts of a magnesium-based compound, 1 to 5 parts of a sulfur-based compound and 1 to 3 parts of an activated silicon-based compound. The treatment method comprises the following steps of sampling inspection, experimental determination of adding proportion, mixing, backfill maintenance, sealing up for safekeeping and the like. The stabilized curing agent disclosed by the invention has an efficient long-term stabilizing effect on various heavy metals such as arsenic, mercury, hexavalent chromium, lead, cadmium, nickel, tin and cyanide, the repeated acid and alkali leaching experiments prove that the stabilized and cured harmful heavy metals cannot be dissolved out again, and the defects that in the traditional technology, the treatment effect and treatment agents are greatly affected by the environment, the long-term efficacy of harmless stabilization is poor, the medicament adding amount is difficult to control and the re-dissolution of harmful heavy metals is easily caused by the high alkalinity of cement solidification and the like are overcome.

The invention relates to a restoration agent for saline-alkali land soil, which consists of free gypsum dehydration, nature organic substance, microbial fertilizer and inorganic nutrient with weight ratio of 60-70:25-35:1-4:3-6; the content of dihydrate calcium sulfate in the free gypsum dehydration is over 80 percent; the nature organic substance consists of weathered coal and grass carbon with weight ratio of 1.0:0.93; the content of effective bacteria in the microbial fertilizer is 2.0 hundred millions/g; and the inorganic nutrient consists of urea, ordinary superphosphate and potassium chloride with weight ratio of 1.0:2.42:075. The restoration agent can utilize calcium ions in the free gypsum dehydration for replacing sodium ions in the soil so as to lower the alkalinity in the soil and provide calcium and sulfur elements for crops, while the nature organic substance can lower and regulate the slat content and the alkalinity in the soil. In addition, the nature organic substance, the microbial fertilizer and the inorganic nutrient can supply large amount of nutrient elements such as nitrogen, phosphorus, potassium and the like to the crop for normal growth, thereby being capable of improving the yield of the crop.