Abstract: The present disclose is directed to a method for controlling iodine levels in wet scrubbers, and, in particular, recirculating wet scrubbers by removing the iodine from the scrubbing solution, such as by using ion exchange, absorption, adsorption, precipitation, filtration, solvent extraction, ion pair extraction, and an aqueous two-phase extraction.

Abstract: A support impregnated with selenium and capable of effectively removing a heavy metal from a process stream that is at an ambient temperature or is at an elevated temperature.

Abstract: A mercury remediation method and apparatus for reducing mercury levels in water to a nanogram per liter level that uses four treatment steps: (1) chelation; (2) oxidation; (3) reduction; and (4) air stripping, vapor/liquid separation. There is a fifth step in the process, which does not involve the wastewater. It is to scrub the stripper air of the volatile mercury in an off-gas adsorption unit or to condense volatile mercury in a cryogenic mercury trap.

Abstract: Disclosed are methods for controlling, mercury emissions, and more particularly, to methods for controlling mercury re-emissions from a wet flue gas desulfurizer used in a combustion process. A method of controlling mercury re-emission from a combustion process includes measuring either mercury concentration, oxidation-reduction, potential (ORP), and/or sulfide concentration within a scrubber liquor of a wet flue gas desulpherizer (wFGD); correlating the mercury concentration, ORP, and /or sulfide concentration with an amount of mercury re-emission additive required in the scrubber liquor to reduce and/or prevent mercury re-emission to a selected level; and adjusting the rate of addition of mercury re-emission additive into the scrubber liquor to attain the selected level of mercury re-emission.

Abstract: Systems and methods for treating a fluid with a body are disclosed. Various aspects involve treating a fluid with a porous body. In select embodiments, a body comprises ash particles, and the ash particles used to form the body may be selected based on their providing one or more desired properties for a given treatment. Various bodies provide for the reaction and/or removal of a substance in a fluid, often using a porous body comprised of ash particles. Computer-operable methods for matching a source material to an application are disclosed. Certain aspects feature a porous body comprised of ash particles, the ash particles have a particle size distribution and interparticle connectivity that creates a plurality of pores having a pore size distribution and pore connectivity, and the pore size distribution and pore connectivity are such that a first fluid may substantially penetrate the pores.

Abstract: An iron composition having a plurality of elemental components is disclosed. The major component is an iron component of at least about 68% to about 92% iron by weight. Other components by weight include manganese; cerium; carbon; phosphorous; sulfur; aluminum; silicon; chromium; copper; and zinc. Combined with layers of sand, brick chips and/or charcoal, the iron composition can be used to create a water filter for filtering inorganic arsenic species and soluble metal ions out of water. To enhance hydrous ferric oxide complexation and precipitation, the iron composition may be treated with food grade acids or a water mixture.

Abstract: The use of a coupling agent containing a mercapto, disulfide, tretrasulfide and/or polysulfide end group provides a mercury removal media having increased reactivity, stability, and mercury removal ability. The mercury removal media described herein is prepared by reacting an organophilic clay containing onium ions with a mercapto, disulfide, tetrasulfide, and/or polysulfide end moiety. Alternatively, the clay can be made organophilic by onium ion reaction prior to or simultaneously with the coupling reaction of the mercapto- or sulfide-end group-containing coupling agent.

Abstract: A method for removing a metal from a metal-containing solution comprising contacting the metal-containing solution with a metal-removing composition comprising a substrate, an organic ion, and a metal binding agent, and recovering a solution having a lowered metal concentration when compared to the metal-containing solution.

Abstract: The invention relates to a method and apparatus for filtering contaminated water from an oil or gas well.

Abstract: An absorbent composition suitable for removing mercury, arsenic or antimony from fluid streams includes 5-50% by weight of a particulate sulphided copper compound, 30-90% by weight of a particulate support material, and the remainder one or more binders, wherein the metal sulphide content of the absorbent, other than copper sulphide, is below 5% by weight.

Abstract: A mercury absorbent comprising a metal sulphide, a support material, a first binder and a second binder, wherein the first binder is a cement binder and the second binder is a high aspect ratio binder having an aspect ratio >2. A mercury removal process comprises contacting a mercury containing feed stream with the absorbent.

Abstract: A method for the reduction of the emission of mercury into the environment from the burning of fossil fuels with the use of polydithiocarbamic compounds. The polydithiocarbamic compounds are used for the capture of mercury from the resulting flue gases using a flue gas desulfrization systems or scrubbers. The method uses polydithiocarbamic compounds in conjunction with a scrubber to capture mercury and reduce its emission and/or re-emission with stack gases. The method is a unique process of reducing the toxic levels of mercury, which allows for the use of coal as a clean and environmentally friendlier fuel source.

Abstract: Methods and apparatus relate to treatment of fluids to remove mercury contaminants in the fluid. Contact of the fluid with active outer surfaces of particles magnetically separable from the fluid loads the particles with the mercury contaminants. Magnetic separation then removes from the fluid the particles loaded with the mercury contaminants such that a treated product remains.

Abstract: The use of a sulfur-impregnated organoclay provides a mercury or arsenic removal media having increased reactivity, stability, and mercury removal ability. The Hg/As removal media described herein is prepared by impregnating an organophilic clay with elemental (free state) sulfur. Alternatively, the clay can be made organophilic by onium ion reaction prior to or simultaneously with impregnating the organoclay with sulfur.

Abstract: A process for removing mercury from an aqueous stream using a supported selenium and sulfur material is disclosed.

Abstract: There are provided methods and processes that employ a mercury-adsorbing granular material as a sorbent to remove mercury from fluids. The fluids can be waste fluids that result from manufacturing, processing, or other treatment processes or systems. The fluids can also be fluids that are treated in their natural state. The fluids to be treated may include water, air, sludge, slurries, gases from processing or furnaces flues, gaseous flows, liquid flows, and other gases and liquids. In one excellent form of the invention, the mercury-adsorbing material includes taconite tailings.

Abstract: The use of a coupling agent containing a mercapto, disulfide, tretrasulfide and/or polysulfide end group provides a mercury removal media having increased reactivity, stability, and mercury removal ability. The mercury removal media described herein is prepared by reacting an organophilic clay containing onium ions with a mercapto, disulfide, tetrasulfide, and/or polysulfide end moiety. Alternatively, the clay can be made organophilic by onium ion reaction prior to or simultaneously with the coupling reaction of the mercapto- or sulfide- end group-containing coupling agent.

Abstract: A method for removing mercury from a fluid stream includes the steps of providing a porous composite material comprising a substrate and a plurality of catalyst and/or photocatalyst particles, and contacting substrate with a fluid stream. The porous composite material adsorbs and/or then oxidizes or reduces metallic species including elemental mercury. A fossil fuel fired power plant can include an emission control device comprising the porous composite material to filter flue gas to and thereby minimize mercury emissions into the environment.

Abstract: Toxic substances such as heavy metals are extracted from a medium using a sorbent composition. The sorbent composition is derived by sulfidation of red mud, which contains hydrated ferric oxides derived from the Bayer processing of bauxite ores. Exemplary sulfidizing compounds are H2S, Na2S, K2S, (NH4)2S, and CaSx. The sulfur content typically is from about 0.2 to about 10% above the residual sulfur in the red mud. Sulfidized red mud is an improved sorbent compared to red mud for most of the heavy metals tested (Hg, Cr, Pb, Cu, Zn, Cd, Se, Th, and U). Unlike red mud, sulfidized red mud does not leach naturally contained metals. Sulfidized red mud also prevents leaching of metals when mixed with red mud. Mixtures of sulfidized red mud and red mud are more effective for sorbing other ions, such as As, Co, Mn, and Sr, than sulfidized red mud alone.

Abstract: A process has steps of one or more of aerobic treatment to remove COD and nitrify a waste stream, anoxic treatment to denitrify a waste stream, anoxic treatment to remove selenium and anaerobic treatment to remove heavy metals and sulphur. The process may be used to treat, for example, FGD blow down water. The process may further include one or more of (a) membrane separation of the waste stream upstream of the anoxic digestion to remove selenium, (b) dilution upstream of the biological treatment step, (c) physical/chemical pretreatment upstream of the biological processes or dilution step to remove TSS and soften the waste stream, or (d) ammonia stripping upstream of the biological treatment steps or dilutions step. These processes may be provided in a variety of suspended growth or fixed film reactors, for example a membrane bioreactor or a fixed film reactor having a GAC bed.

Abstract: An amalgam separator for purifying a waste stream that contains a mixture of air and waste liquid. The amalgam separator contains filter media that comprises a sulfur-impregnated carrier and an ion exchange resin, wherein the ion exchange resin is present at a concentration of from about 25 to about 75 weight percent. During its operation, the amalgam separator separates the waste stream into air and waste liquid portions, purifies the waste liquid portion, and then combines the purified waste liquid portion with the air.

Abstract: A sorbent composition comprising a vanadium compound and a ZrO2 support material is disclosed. Methods of making and using the composition to remove heavy metals or heavy metal containing compounds from a fluid stream are also provided. Such methods are particularly useful in the removal of mercury and mercury compounds from flue gas streams produced from the combustion of hydrocarbon-containing materials such as coal and petroleum fuels.

Abstract: A composition comprising a vanadium oxide compound and an alkali metal promoter loaded onto a porous support material is disclosed. Methods of making and using the composition to remove heavy metals or heavy metal containing compounds from a fluid stream are also provided. Such methods are particularly useful in the removal of mercury and mercury compounds from flue gas streams produced from the combustion of hydrocarbon-containing materials such as coal and petroleum fuels.

Abstract: A process for removing mercury from an aqueous stream using a supported selenium and sulfur material is disclosed.

Abstract: There are provided methods and processes that employ a mercury-adsorbing granular material as a sorbent to remove mercury from fluids. The fluids can be waste fluids that result from manufacturing, processing, or other treatment processes or systems. The fluids can also be fluids that are treated in their natural state. The fluids to be treated may include water, air, sludge, slurries, gases from processing or furnaces flues, gaseous flows, liquid flows, and other gases and liquids. In one excellent form of the invention, the mercury-adsorbing material includes taconite tailings.

Abstract: Mercury is removed from solutions contaminated with mercury, the solution contaminated with mercury being introduced into a distillation column above the column bottom, solvent being distilled off and solution depleted in mercury being stripped off at the column bottom.

Abstract: This invention relates to a method for removing mercury from dilute sulphuric acid. According to the method sulphuric acid solution is scrubbed with an aqueous solution containing thiosulphate, which precipitates the mercury present in the sulphuric acid solution either as mercury sulphide or, in a chlorine-containing environment, as a mercury sulphide-mercury chloride double salt. The quantity of thiosulphate to be fed is adjusted so that it precipitates the mercury in the sulphuric acid solution, but still does not form elemental sulphur.

Abstract: The invention relates to the use of used alumina to reduce the level of inorganic contaminants, such as mercury and arsenic, from waste fluid streams. The invention further provides a process for reducing the level of mercury or arsenic in fluid streams by contacting the fluid stream with used alumina, such as used Claus catalyst.

Abstract: A process by which heat is removed from a reactant fluid to reach the operating temperature of a known pollutant removal method and said heat is recirculated to raise the temperature of the product fluid. The process can be utilized whenever an intermediate step reaction requires a lower reaction temperature than the prior and next steps. The benefits of a heat-recirculating cooler include the ability to use known pollutant removal methods and increased thermal efficiency of the system.

Abstract: A method for removing metal contaminants from water uses lignin derivatives, such as lignosulfonates and kraft lignin, a coagulant, such as a metal salt, and a pH-increasing composition. The lignin derivative is dispersed in the contaminated water, the coagulant is added and the pH is adjusted as required to cause flocculation. A sludge is formed that contains the metals and that is separated from the treated water by filtration. Related methods are used to reduce the leachable metal content of contaminated soils. The invention also provides a composition for stabilizing the metal contaminants in soil, comprising lignin derivatives, a coagulant and a composition for increasing the pH. The mixture is blended with the contaminated soil, reducing its leachable metal content.

Abstract: A sorbent composition comprising a vanadium compound and a TiO2 support material is disclosed. Methods of making and using the composition to remove heavy metals or heavy metal containing compounds from a fluid stream are also provided. Such methods are particularly useful in the removal of mercury and mercury compounds from flue gas streams produced from the combustion of hydrocarbon-containing materials such as coal and petroleum fuels.

Abstract: Mercury is removed from solutions contaminated with mercury by filtration through a carbon filter consisting of electrode graphite.

Abstract: The present invention relates to compositions and methods for the removal of toxic metals or radionuclides from source materials. Toxic metals may be removed from source materials using a clay, such as attapulgite or highly cationic bentonite, and chitin or chitosan. Toxic metals may also be removed using volcanic ash alone or in combination with chitin or chitosan. Radionuclides may be removed using volcanic ash alone or in combination with chitin or chitosan.

Abstract: A two-step chemical precipitation process involving hydroxide precipitation and sulfide precipitation combined with “field separation ” technology such as magnetic separation, dissolved air flotation, vortex separation, or expanded plastics flotation, effectively removes chelated and non-chelated heavy metal precipitates and other fine particles from water. In the first-step, the non-chelated heavy metals are precipitated as hydroxides and removed from the water by a conventional liquid/solids separator such as an inclined plate clarifier to remove a large percentage of the dissolved heavy metals. The cleaned water is then treated in a second precipitation step to remove the residual heavy metals to meet discharge limits. In the second precipitation step, any metal precipitant more effective than hydroxide for metal precipitation can be used.

Abstract: The invention relates to a particular polymer which is derived from a copolymer polysaccharide formed by a main chain comprising similar or different anhydrohexose units and branches including at least one neutral or anionic anhydropentose and/or anhydrohexose unit. Moreover, the invention relates to the use of said polymer in the treatment of aqueous media, in particular the treatment of aqueous effluents containing heavy metals, the treatment of waste water, drinking water and for sludge conditioning. Said derivative polymer comprises one or more units bearing an oxime function at least at position C2.

Abstract: A method for in situ bioremediation of contaminants in the environment is described. The method includes adding an electron donor to ground water in an amount sufficient for a microbe in the ground water to use the electron donor for reducing the contaminant into an innocuous derivative thereof. Illustratively, the electron donor contains about 0.1 to 75% by weight of chitin, such as crustacean shell, partially deproteinized crustacean shell, ground mushrooms, or a fungal fermentation broth. The chitinous electron donor can be added to the ground water as a particulate solid or aqueous slurry.

Abstract: The invention is related to a method and an installation for removal of metal cations contained in a liquid, in which said liquid is brought into contact at a temperature greater than or equal to 60° C. with a chelating ion exchange resin formed from a polyazacycloalkane grafted on a solid support, said resin having been conditioned, previously to said contacting, at a pH of 4 to 6.

Abstract: The present invention is directed to processes for removing a contaminant from dental effluents and includes transporting a three-phase effluent through a suction line into a particle collection vessel, introducing a suction line cleaning solution which includes a reagent into the suction line, and introducing the three phase effluent and the line cleaning solution into the collection vessel, wherein the effluent separates into solid. liquid, and gas phases in the collection vessel and the reagent includes a flocculant and/or a precipitant. and removing the gaseous and liquid phases from the collection vessel. The contaminant includes mercury. lead. and arsenic.

Abstract: A process for the selective removal of toxic heavy metals from a flowing stream of water involves causing the stream to flow through a stationary bed of particulate polymer having amine functional groups, and injecting into the stream, adjacent the upstream extremity of the bed, a substantially continuous flow of carbon disulfide.

Abstract: A method for removing metal contaminants from water uses lignin derivatives, such as lignosulfonates and kraft lignin, a coagulant, such as a metal salt, and a pH-increasing composition. The lignin derivative is dispersed in the contaminated water, the coagulant is added and the pH is adjusted as required to cause flocculation. A sludge is formed that contains the metals and that is separated from the treated water by filtration. Related methods are used to reduce the leachable metal content of contaminated soils. The invention also provides a composition for stabilizing the metal contaminants in soil, comprising lignin derivatives, a coagulant and a composition for increasing the pH. The mixture is blended with the contaminated soil, reducing its leachable metal content.

Abstract: A method for treating (in situ) large bodies of water contaminated with heavy metals and having varying density stratas to immobilize the contaminant metals is disclosed. The method, or process for (in situ) immobilization of metals is focused on treating large bodies of water having metals therein that are also adjacent a border of soil or earthen materials in an attempt to immobilize the metals from penetrating through the soil. The method is also able to treat the soil water boundary within the pit lake to provide additional immobilization. The pit lakes can include open pit lakes, subterranean mine lakes, flowing streams and the like. The method is also able to treat an abandoned mine prior to the filling of the mine with water. Initially, the density mean of the body of water is determined, which is densest typical at regions at or approaching 4 degrees C.

Abstract: The present invention is directed to a process and apparatus for removing and stabilizing mercury from mercury-containing gas streams. A gas stream containing vapor phase elemental and/or speciated mercury is contacted with reagent, such as an oxygen-containing oxidant, in a liquid environment to form a mercury-containing precipitate. The mercury-containing precipitate is kept or placed in solution and reacts with one or more additional reagents to form a solid, stable mercury-containing compound.

Abstract: Methods and apparatus are disclosed for remediating metal contaminants using hydrocarbons which stimulate the growth of hydrocarbon-utilizing bacteria. The metal contaminants may include heavy metals such as arsenic, antimony, beryllium, cadmium, chromium, copper, lead, mercury, iron, manganese, magnesium, radium, nickel, selenium, silver, thallium and zinc. The hydrocarbon may include alkanes, alkenes, Aalkynes, poly(alkene)s, poly(alkyne)s, aromatic hydrocarbons, aromatic hydrocarbon polymers and aliphatic hydrocarbons. Butane is a particularly suitable hydrocarbon which stimulates the growth of butane-utilizing bacteria. Remediation may occur in-situ or ex-situ, and may occur under aerobic, anaerobic or dual aerobic/anaerobic conditions. Examples of applications include the remediation of heavy metals, the remediation of arsenic impacted surface water, groundwater and/or soil, the remediation of acid mine drainage, and the treatment of spent metal plating solutions.

Abstract: A two-step chemical precipitation process involving hydroxide precipitation and sulfide precipitation combined with “field separation” technology such as magnetic separation, dissolved air flotation, vortex separation or expanded plastics flotation, effectively removes chelated and non-chelated heavy metal precipitates and other fine particles from water. In the first-step, the non-chelated heavy metals are precipitated as hydroxides and removed from the water by a conventional liquid/solids separator such as an inclined plate clarifier to remove a large percentage of the dissolved heavy metals. The cleaned water is then treated in a second precipitation step to remove the residual heavy metals to meet discharge limits. In the second precipitation step, any metal precipitant more effective than hydroxide for metal precipitation can be used.

Abstract: A product and method for the removal of pollutant heavy metals from aqueous solutions which precludes the end user from storing, handling, feeding and controlling hazardous soluble sulfide materials. The product is a slurry which includes a mixture of a liquid medium and an essentially insoluble salt wherein the salt is the reaction product of heavy metal ions, preferably selected from Mn++ ions, Fe++ ions, and Fe+++ ions, and sulfide ions derived from soluble sulfide sources such as sodium sulfide, hydrogen sulfide, and sodium hydrosulfide. Addition of the subject slurry to a wastewater stream will effect the precipitation of heavy metals with lesser equilibrium sulfide ion concentrations than that of the essentially insoluble salt. Solids collected by this method may be returned to subsequent wastewater streams for additional removal of heavy metals by any excess heavy metal sulfide salt.

Abstract: A fiber capable of forming a metal chelate and a process for producing the same are disclosed, wherein the fiber is characterized in that at least one metal chelate-forming compound selected from the group consisting of aminocarboxylic acid, aminocarboxylic acid, thiocarboxylic acid and phosphoric acid, which are reactive with a glycidyl group, is bonded to a molecule of a synthetic fiber through a crosslinkable compound having a reactive double bond and a glycidyl group in its molecule. The chelate-forming fiber is excellent in capturing harmful heavy metal ions and can be easily produced in a simple and safe way at a low cost.

Abstract: A metal waste recovery process for recovering useful material from a quantity of waste material. The waste material is a composition including oil, metals and organic materials. The first step of the process is to deposit the waste material into a slurry tank and to add water to the waste material to produce a mixable slurry. The slurry is then high energy mixed to evenly distribute the waste material throughout the slurry. The useful metal is then recovered from the slurry using a magnetic separator. The remaining waste material is transferred into an anaerobic reactor where the remaining waste material reacts with anaerobic organisms provided by bacteria in a sludge seed. The anaerobic reaction between the anaerobic organism and the organic materials of the waste material produces recoverable inorganic gases that are removed from the waste material slurry. The recovered inorganic gases are transferred to a storage vessel and compressed.

Abstract: A bead is provided which comprises or consists essentially of activated carbon immobilized by crosslinked poly(carboxylic acid) binder, sodium silicate binder, or polyamine binder. The bead is effective to remove metal and other ionic contaminants from dilute aqueous solutions. A method of making metal-ion sorbing beads is provided, comprising combining activated carbon, and binder solution (preferably in a pin mixer where it is whipped), forming wet beads, and heating and drying the beads. The binder solution is preferably poly(acrylic acid) and glycerol dissolved in water and the wet beads formed from such binder solution are preferably heated and crosslinked in a convection oven.

Abstract: The present invention is directed to processes for removing a contaminant from dental effluents and includes transporting a three-phase effluent through a suction line into a particle collection vessel, introducing a suction line cleaning solution which includes a reagent into the suction line, and introducing the three phase effluent and the line cleaning solution into the collection vessel, wherein the effluent separates into solid, liquid, and gas phases in the collection vessel and the reagent includes a flocculant and/or a precipitant, and removing the gaseous and liquid phases from the collection vessel. The contaminant includes mercury, lead, and arsenic.

Abstract: Disclosed are methods, devices and apparatus for bioremediation of mixed waste aquifers, based on a synergistic combination of reductive treatment using zero-valent iron and anaerobic biotransformations. Also disclosed are methods for in situ and ex situ remediation of groundwater and wastewater via these iron-bacterial compositions in a variety of devices including batch reactors, permeable and semipermeable reactive barriers, flow-through reactors, fluidized bed reactors, and sediment tanks.