5795 results about "Heavy metals pollution" patented technology

The invention provides a plasma processing apparatus aimed at suppressing the corrosion caused by reactive gas and heavy-metal contamination caused by plasma damage of components constituting the high-frequency electrode and gas supply unit. The plasma processing apparatus comprises a processing chamber 1 for subjecting a processing substrate 4 to plasma processing, gas supply means 17, 16 and 11 for feeding gas to the processing chamber 1, and an antenna electrode 10 for supplying high-frequency radiation for discharging the gas to generate plasma, wherein the gas supply means includes a gas shower plate 11 having gas discharge holes on the surface exposed to plasma, and a portion of or a whole surface of the conductor 10 exposed to gas constituting the antenna-electrode side of the gas supply means is subjected to ceramic spraying containing no heavy metal to form a protecting film 12.

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.

The modified octahedral zeolite is prepared through the once exchange reaction of octahedral zeolite, phosphorus compound and ammonium compound, the further reaction inside exchange slurry with introduced RE solution, filtering, washing and roasting in vapor. The catalyst contains the modified octahedral zeolite 5-45 wt%, clay 15-85 wt% and heat resistant inorganic oxide 15-85 wt%. The catalyst is prepared through mixing the zeolite component, clay and the precursor of the heat resistant inorganic oxide, spraying to form and washing. The catalyst has high activity stability, high gasoline yield, low coke yield, strong heavy oil cracking capacity and high heavy metal pollution resistance.

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.

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 invention discloses a chemical leaching restoring method for soil polluted by heavy metals. Na2EDTA solution is utilized to perform leaching to the soil polluted by the heavy metals, available cadmium and lead in the soil are effectively removed, Na2S.9H2O is utilized to precipitate the heavy metals in filtrate, Na2EDTA is released again, and repeated recycling of the Na2EDTA solution is achieved. After recycling, the Na2EDTA solution carries out leaching to the soil polluted by the heavy metals, the removing rate of available Cd in the polluted soil reaches 81.6-81.8%, and the removing rate of available Pb reaches 55.9-60.1%. The chemical leaching restoring method for the soil polluted by the heavy metals overcomes the shortcomings that an existing method for the Na2EDTA solution to perform leaching to the soil polluted by the heavy metals causes chemical cost to be large, generated filtrate is much, and the follow-up treatment is troublesome. Simultaneously, the chemical leaching restoring method for the soil polluted by the heavy metals has the advantages of being simple in process, becoming effective quickly, enabling a leaching agent to be reused, and enabling the heavy metals to be effectively eliminated.

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 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 discloses a bioremediation method for soil polluted by heavy metals. The bioremediation method comprises the following steps of: adding earthworm feeds into the soil polluted by the heavy metals, turning the soil, uniformly mixing, and putting earthworms into the soil and cultivating the earthworms; after the earthworms are cultivated for 28 to 35 days, collecting earthworm excrements in the upper layer soil, collecting adult earthworms by adopting a natural lighting method, and retaining young earthworms and earthworm eggs in the soil; planting plants by adopting a hedge planting method, cradling the parts of the plants growing for 78 to 90 days, which are positioned above the ground, and removing the whole plants after the plants grow for another 50 to 70 days; collecting the adult earthworms and the earthworm excrements for 1 to 3 days by adopting an outdoor collection method every 28 to 35 days during planting of the plants; and after the whole plants are removed, collecting all the adult earthworms and the young earthworms by adopting the natural lighting method, and collecting the earthworm excrements and the earthworm eggs. The soil is subjected to remediationby combining animals, plants and microorganisms according to a proper remediation sequence and a remediation period, so that the bioremediation method is economic, environment-friendly, easy to operate, high in remediation efficiency and easy to popularize, and is particularly suitable for mild or moderate copper, cadmium and lead combined polluted soils.

The invention discloses a composite heavy metal polluted soil conditioner as well as application and an application method thereof. The soil conditioner comprises the following components: plant ash, calcium magnesium phosphate, quicklime, zeolite and organic fertilizers at a weight ratio of (0.3-1.1):(0.1-1.2):(0.4-2.1):(0.1-0.6):(0.008-0.06):(0.4-1.2). Through inorganic components such as quicklime, calcium magnesium phosphate and phosphate in hydroxyapatite as well as potassium carbonate in the plant ash, the soil conditioner can be used for fixing heavy metals in polluted soil and improving the fertility of the polluted soil in combination with organic manures such as the plant ash and the organic fertilizers so as to continuously intensify the restoration of the polluted soil, has the advantages of relatively-high stability, good environmental friendliness and low cost, can be used for inactivating and restoring various heavy metal polluted soil, especially has a good restoration effect on soil pollution caused by waste slag discharged by industrial and mining enterprises, can be used for realizing the treatment goal without generating secondary pollution, and is liable to realize large-area popularization.

The invention discloses a granular filtering material for adsorbing and removing heavy metals in water and a preparation method thereof. The granular material consists of the following components in part by mass: 80-120 parts of an adsorbent, 7-14 pats of an additive and 0.5-3 parts of a binding agent, wherein the adsorbent consists of the following components in part by mass: 50-70 parts of coal ash and 30-50 parts of zeolite powder or sea-foam stone powder; the additive consists of the following components in part by mass: 5-7 parts of Mg-Al hydrotalcite, 2-6 parts of biochar and 0.5-1 part of magnesium Lignosulfonate; the binding agent is bentonite. The granular filtering material is prepared through the steps of adsorbent acid modification, biochar preparation, granulation and heat treatment process. According to the invention, the prepared granular filtering material is 3-6 mm in granule size, is large in adsorption capacity and excellent in adsorption effect and can effectively remove heavy metals in water, and no secondary pollutants are dissolved out, so that the granular filtering material can be applied to the treatment on heavy metal micro-polluted water and industrial waste water containing heavy metals, and has good economic and social benefits.

An electrodynamic method for repairing the soil polluted by heavy metal includes using ion exchange film to isolate cathode from said soil, inserting porous ceramic between said film and soil, controlling the pH value of soil by the H and OH ions generated by electrodes themsolves for speeding up the extraction of pollutants, depositing heavy metals in cathode solution, centrifugal purifying to obtain heavy metal compound, and using clean cathode solution to neutralizing soil.

The invention discloses a preparation method of a functional organic fertilizer for soil restoration. The method comprises the following steps: mixing crushed straws with blue-green algae according to the mass ratio of (1-5):10 to obtain a mixture, and then adding a biomass-transformed complex microbial inoculant and a biomass-transformed inductive material to the mixture; evenly mixing and then carrying out conventional stacking fermentation for 5-15 days, so as to obtain a semi-solid organic fertilizer; and mixing and pelletizing the semi-solid organic fertilizer, clay, biomass carbon ash and a heavy metal ion chelating agent according to the ratio of 1000:(50-200):(50-150):(1-5), so as to obtain the functional organic fertilizer for soil restoration. The organic fertilizer disclosed by the invention has a persistent slow-release fertilizer effect, and can adsorb, chelate and immobilize the heavy metal ions in a deactivation manner, soil fleeciness is facilitated, the moisture retention and the breathability are improved, rooting of plants is facilitated, formation of beneficial components of soil microelements and the like is optimized, the heavy metal-polluted soil is effectively restored, and secondary pollution of the soil is not caused.

The invention relates to the field of environmental protection and restoration and in particular relates to an environmental-friendly heavy metal stabilizer used for soil restoration of an industrial pollution site and an application method thereof. The environmental-friendly heavy metal stabilizer is prepared from the following material components in parts by weight: 40-50 parts of clay mineral, 17-24 parts of adsorbing material, 10-18 parts of heavy metal chelating agent, 4-8 parts of heavy metal precipitating agent and 10-15 parts of alkaline modifier. Main ingredients of the adopted stabilizer are natural materials, heavy metal pollutant in soil can be rapidly and effectively stabilized through composite action such as chelating, precipitation and adsorption; the heavy metal pollutant is stabilized for a long time, toxicity and biological availability of the heavy metal pollutant can be reduced, risk of the heavy metal polluted soil to the environment and human health is reduced, and the heavy metal polluted soil is restored; besides, a soil texture improving ingredient is contained, so that soil is restored while tillability of the soil is improved.

The invention provides a decision-making system and method for heavy metal pollution of farmland soil. The method is based on monitoring data of heavy metal pollution of farmland soil in a monitoringarea, constructs a farmland soil heavy metal pollution risk comprehensive assessment index system, a graded early warning model, an emergency disposal model and a crop planting adjustment model to assess the risk of heavy metal pollution in the farmland soil and quickly make an emergency response, and at the same time, can also adjust the planting structure of crops in a heavily polluted area. Thesystem includes data collection, data management, risk assessment, graded early warning, emergency disposal, planting adjustment and information visualization modules which are used for monitoring, assessing and responding quickly to heavy metal pollution in the farmland soil. The decision-making system and method for the heavy metal pollution in the farmland soil according to the invention can significantly improve the automation and intelligence levels of management decision making of the heavy metal pollution in the farmland soil.

The invention discloses a composite passivant for soil polluted by heavy metal and a preparation method thereof. The composite passivant is prepared by three raw materials of power plant slags, sepiolite mineral powder and calcined lime in proportion. The preparation method comprises the following steps: A. preparing the power plant slags; B. preparing the sepiolite mineral powder preparation; and C. evenly mixing the raw materials prepared by steps A and B with the calcined lime, wherein the mixture is the composite passivant. By utilizing the composite passivant, the contents of the effective constituents, such as silicon oxide, magnesium oxide, calcium oxide, ferric oxide and the like lowering the soil heavy metal activity is 78.2-90.6% which is calculated by the sum of SiO2, MgO, CaO, MnO2 and Fe2O3; the composite passivant can be widely used in various soils polluted by the heavy metal, especially the soil with visco-weight texture; and by using the composite passivant, the contents of cadmium and lead in a soil active state in the pollutant farmland are lowered by 15.9-48.4% and 26.2-56.4% respectively; the contents of the cadmium and the lead of agricultural products are lowered by 13.6-43.9% and 22.1-53.2% respectively; and the soil pH value is also improved by 0.21-0.46%. The composite passivant has various functions of passivating soil heavy metal, repairing acidification soil and improving the soil tilth and the like.

The invention discloses an ectopic classification leaching repair complete process of arsenic and heavy metal contaminated soil. The repair process comprises the following steps: the contaminated soil is magnetically separated to extract and recover target metals; a nonmagnetic component is divided into three grades by a vibrating screen after being primarily crushed; stones and boulders are flushed by clear water to directly serve as building materials; thick and fine soil particles obtained through screening respectively enter second-grade leaching mixing equipment for washing; the solid-liquid separation is performed for mud generated by washing through a two-stage hydraulic cyclone device; leaching waste liquid is purified and regenerated for recycling; sludge is added with such repair materials as curing/stabilizing agents for safety treatment after being dehydrated; and after the treatment, the soil particles can be backfilled, or can serve as roadbeds, building materials and the like. Based on the characteristic of large difference of arsenic and heavy metal contents in soils with different particle sizes, the soil leaching treatment according to the particle size is performed, so that the process has such advantages as low repair cost, high treatment efficiency and saving of energy consumption, provides a new method for soil heavy metal pollution abatement, and is broad in application prospect.

The invention discloses a heavy metal contaminated soil conditioner and a plant and chemistry combined remediation method. The heavy metal contaminated soil conditioner is a mixture of red mud and slaked lime. In the invention, the plant and chemistry combined remediation method is used, the pH of the soil is regulated by a chemical method, and heavy metals in the soil are absorbed by planting energy crops, hyperaccumulative plants and the like, thereby improving the soil properties, gradually reducing the content of heavy metals in the soil, finally achieving the purpose of soil remediation, improving the plant remediation efficiency, and being favorable to large-scale commercial application.

The invention provides a soil heavy metal composite passivating agent, comprising the following raw materials in percentage by mass of: 25% of slaked lime, 10-20% of monopotassium phosphate, 20-45% of plant ash and 20-45% of silkworm excrement. With the adoption of the soil heavy metal composite passivating agent disclosed by the invention, compared with a control group, an effective state lead content of the soil polluted by heavy metal is reduced by 20.23-47.61% within culture time of 30 days, and an effective state cadmium content is reduced by 20.15-50.57%; the passivating effect of the soil heavy metal composite passivating agent on the heavy metal is extremely obvious; and meanwhile, compared with the control group, the content of organic matters is improved by 48.62-64.47%, and the soil fertility is obviously improved. A method disclosed by the invention is applicable to repairing large-area heavy metal polluted soil and comprises the steps of repairing a heavy metal polluted farmland and repairing a heavy metal polluted mine; and the method has the advantages of lower cost, rapidness for repairing, simplicity in operation, feasible method and extremely great popularization value.

A stabilizer suitable for heavy metal contaminated soil and an application method thereof belong to the technical field of contaminated soil remediation treatment. The invention is characterized in that: the soil stabilizer comprises the following components by mass: 5%-8% of heavy metal chelants, 10%-20% of gelled materials, 50%-65% of clay mineral, 10%-15% of alkaline excitants; the gelled material, clay mineral and alkaline excitant are mixed and grinded to obtain a Blaine specific surface area of 5000-8000 cm2/g; the mixture is sieved by a 200-mesh sieve, and the water content is less than 3%; the heavy metal chelant is prepared into a solution by water with a mass percent of the chelant being 20%-40%. The stabilizer and soil are uniformly mixed, and conserved for above 5 days. The main components of the stabilizer are mostly natural materials; after the stabilizer is used, heavy metal contaminants in soil can be rapidly and effectively stabilized, and the toxicity of the contaminants is reduced. The materials used are economical and easily available, and do not cause secondary contamination, and the stabilizer is a rapid and high-efficient stabilizer for heavy metal contaminated soil.

The invention discloses a modeling method of a soil heavy metal content detection model and the application thereof. The modeling method includes the steps of collecting a soil sample, collecting the X-ray fluorescence spectrum of the sample, measuring the reference value of heavy metal element content to be measured in the soil sample, and establishing the correcting relation between the X-ray fluorescence spectrum and the reference value of heavy metal element content. The method can simultaneously perform rapid nondestructive examination to various heavy metal element contents of soil, has wide range of application and high universality and provides a technological base for the on-site detection of farmland soil heavy metal pollution.