Abstract: A system and method for removing mercury from the flue gas of a coal-fired power plant is described. Mercury removal is by adsorption onto a thermally activated sorbent produced in-situ at the power plant. To obtain the thermally activated sorbent, a lance (thief) is inserted into a location within the combustion zone of the combustion chamber and extracts a mixture of semi-combusted coal and gas. The semi-combusted coal has adsorptive properties suitable for the removal of elemental and oxidized mercury. The mixture of semi-combusted coal and gas is separated into a stream of gas and semi-combusted coal that has been converted to a stream of thermally activated sorbent. The separated stream of gas is recycled to the combustion chamber. The thermally activated sorbent is injected into the duct work of the power plant at a location downstream from the exit port of the combustion chamber. Mercury within the flue gas contacts and adsorbs onto the thermally activated sorbent.

Abstract: A process for removing vapor phase contaminants from a gas stream includes the step of adding a raw carbonaceous starting material into a gas stream having an activation temperature sufficient to convert the raw carbonaceous starting material into an activated material in-situ. The activated material then adsorbs the vapor phase contaminants, and the activation material containing the vapor phase contaminants is removed from the gas stream using a particulate collection device. The process is particularly suited for the removal of vapor phase air toxics, such as mercury, from the flue gas of a combustion process. An apparatus for the removal of vapor phase contaminants from a gas stream is also described.

Abstract: A method of removing trace contaminants, such as mercury, from a flue gas by passing the gas over a sorbent structure on which is coated a renewable layer of sorbent. The sorbent structure can be a tube or plate and can be porous or non-porous and is placed inside a duct through which the flue gas flows. The sorbent particles comprise noble metal or activated carbon particles and can be injected into the gas stream before it passes over the sorbent structures. The sorbent structures can be periodically recoated with sorbent while the gas is still flowing.

Abstract: A method and apparatus for controlling or removing mercury, mercury compounds and high molecular weight organics, if present, from a resource recovery exhaust stream by separately adding a carbonaceous char to the flue gas while it is still within the unit. The char can be produced in situ by adding a carbonaceous material and allowing it to thermally decompose.

Abstract: A method and apparatus for controlling or removing mercury, mercury compounds and high molecular weight organics, if present, from a waste incineration apparatus exhaust stream by separately adding a carbonaceous char to the flue gas while the flue gas is still within the unit. The char can be produced in situ by adding a carbonaceous material and allowing the carbonaceous material to thermally decompose.

Abstract: A process for removing mercury and organic compounds from gaseous streams using an adsorption powder, characterized as containing a carbon-based powder selected from the group consisting of coal carbons, wood carbons, graphite carbons, activated carbons, coconut shell carbons, peat carbons, petroleum cokes, synthetic polymers, the like, and combinations thereof, and an effective amount, suitable for removing mercury and organic compounds, of cupric chloride, the process being characterized by the steps of:

Abstract: Adsorption of mercury on activated carbons derived from scrap tires enables the removal and recovery of mercury from combustion/incineration flue gas, with concurrent control of SO2 and NOx.

Abstract: An activated carbon catalyst having sulfur dispersed homogeneously thereon, the sulfur being chemically bonded to the activated carbon. A method of making the catalyst involves forming an intimate mixture of a synthetic carbon precursor and a sulfur-containing material, curing the carbon precursor, carbonizing the carbon precursor, activating the carbonized carbon precursor to produce an activated carbon catalyst having sulfur chemically bonded to said activated carbon and uniformly dispersed thereon.

Abstract: A process for the purification of a fluid stream containing a sulphur contaminant, such as hydrogen sulphide, and mercury, phosphine, stibine, and/or arsenic compounds as a second contaminant wherein said fluid stream is passed through a bed of a particulate absorbent containing a sulphide of a variable valency metal, especially copper, that is more electropositive than mercury, to remove said second contaminant and then the sulphur contaminant is removed from at least part of the effluent from that bed by passing that part of the effluent through a bed of a particulate sulphur absorbent comprising a compound selected from oxides, hydroxides, carbonates and basic carbonates of said variable valency metal is disclosed. The removal of the sulphur contaminant converts said variable valency metal compound to the corresponding sulphide. The resulting bed of variable valency metal sulphide is subsequently used for the removal of the second contaminant.

Abstract: An apparatus for economically handling mercury containing lamps in an efficient manner while protecting the environment against release of mercury vapors into the atmosphere. The apparatus includes a mobile vehicle which is transportable to a facility or site where the mercury containing lamps to be destroyed are located, a mechanism mounted within an enclosure on the mobile vehicle for receiving and destroying the mercury containing lamps therewithin, and an apparatus for sensing mercury vapor levels within the enclosure of the vehicle.

Abstract: An apparatus and method are described for removing vapor phase contaminants from a gas stream by placing a porous element having a sorbent material into ductwork through which the gas stream passes. In a first mode of operation, vapor phase contaminants are adsorbed by the sorbent. In a second mode of operation, the porous element is cleaned of any accumulated deposits, for example fly ash, while in place without having to stop the gas flow. In a third mode of operation, the sorbent can be regenerated in place and without having to stop the gas flow by heating and collecting the desorbed contaminants. This invention is particularly suited for the removal of vapor phase mercury from flue gas generated by a combustion process.

Abstract: Regenerative adsorption of mercury on activated carbons derived from scrap tires enables the removal and recovery of mercury from combustion/incineration flue gas, with concurrent control of SO.sub.2 and NO.sub.x. Flue gas is used for regeneration of the activated carbon, and mercury stripped from the activated carbon is recovered downstream of the regenerator.

Abstract: Mercury emission from a flue gas such as that generated by a coal fired power plant is controlled by injecting into the flue gas unburned carbon purified from ash such as fly ash or wood ash. The unburned carbon adsorbs the mercury and is later removed from the flue gas by a particle separator. The unburned carbon collected from ash is significantly lower in cost compared to activated carbon presently used in such a process. The unburned carbon is concentrated in the sorbent by one or more separation processes used to remove non-carbon particles from the fly ash. These processes include gravity separation, electrostatic separation, froth flotation, magnetic separation and size classification. Mercury adsorption is further increased by oxidation of the carbon surface.

Abstract: A process for the purification of a fluid stream containing a sulphur contaminant, such as hydrogen sulphide, and mercury, phosphine, stibine, and/or arsenic compounds as a second contaminant wherein said fluid stream is passed through a bed of a particulate absorbent containing a sulphide of a variable valency metal, especially copper, that is more electropositive than mercury, to remove said second contaminant and then the sulphur contaminant is removed from at least part of the effluent from that bed by passing that part of the effluent through a bed of a particulate sulphur absorbent comprising a compound selected from oxides, hydroxides, carbonates and basic carbonates of said variable valency metal is disclosed. The removal of the sulphur contaminant converts said variable valency metal compound to the corresponding sulphide. The resulting bed of variable valency metal sulphide is subsequently used for the removal of the second contaminant.

Abstract: The invention relates to a process for removing and recovering mercury, an impurity, from a hydrocarbon feedstream. The process comprises separating the hydrocarbon feedstream into a gaseous portion and a liquid hydrocarbon portion and separately treating the gaseous and liquid portions by adsorption in separate purifier beds. The gas and liquid purifier beds are regenerated sequentially with a heated regenerant stream that following desorption and recovery of mercury is further purified in a secondary regenerable adsorption bed. The sequential regeneration of the two separate purifier beds and the secondary adsorbent bed significantly reduces the capital and operating cost for the process and serves to concentrate the mercury in the secondary adsorbent bed where it can be removed at a lower cost.

Abstract: An apparatus and method are described for removing vapor phase contaminants from a gas stream by placing a porous tube having a sorbent material into ductwork through which the gas stream passes. In a first mode of operation, vapor phase contaminants are adsorbed by the sorbent. In a second mode of operation, the porous tube is cleaned of any accumulated deposits, for example fly ash, while in place without having to stop the gas flow. In a third mode of operation, the sorbent can be regenerated in place and without having to stop the gas flow by heating and collecting the desorbed contaminants. This invention is particularly suited for the removal of vapor phase mercury from flue gas generated by a combustion process.

Abstract: The exhaust gas stream is passed through a bed of a granular adsorbent for separating noxious substances. The bed consists of the mixture of a granular high-carbon material and a granular inert material. The bulk density of the inert material is 0.8 to 3 times the bulk density of the carbonaceous material. Preferably, the content of the high-carbon material in the bed is 5 to 80 wt-%. The high-carbon material may for instance be activated carbon, activated coke or lignite coke. As inert material there may for instance be used siliceous rock, pumice, lava, slag, vitrification residues or fine gravel.

Abstract: A method for removing vapor phase contaminants from a gas stream. Sorbent particles are injected into the gas stream to react with vapor phase contaminants in the gas stream. Each sorbent particle is made from a support particle of a material coated with a layer of sorbent material different than the material of the support particle. The gas stream is directed through a particulate control device to remove the sorbent particles from the gas stream. A sorbent particle for use in the method and a method for manufacture of the sorbent particle are provided.

Abstract: A method is described for quantitative determination of mercury present in a sample (liquid or solid). The method involves converting mercury compounds to elemental mercury, removing all elemental mercury from the sample in vapor form by means of vacuum, passing the mercury vapor through a column which absorbs and captures all of the mercury vapor by converting it to a halide compound, eluting the mercury halide from the column, and colorimetrically analyzing for the amount of mercury halide collected.

Abstract: Toxic metal vapor phase compounds, and in particular, mercury and cadmium, are removed from waste incinerator combustion gases by contact with dry alkaline material and dry activated carbon followed by solids separation. The resulting gas is subjected to quench/wet scrubbing with recycle hydrochloric acid solution formed in situ by absorption of HCl from the gas. Blowdown liquid withdrawn from the recycle acid liquor, may be recycled to the incinerator or further treated by neutralization, precipitation, and filtration of the precipitated toxic metals.

Abstract: The process of purifying oxygen-containing exhaust gases produced by combustion of waste materials including garbage, industrial waste and sewage sludge includes reacting an exhaust gas containing pollutants in a gas-solids suspension at a temperature of 120.degree. to 140.degree. C. and at a gas velocity from 3 to 20 m/s for a reaction time of 0.5 to 10 seconds with a mixture containing naturally occurring zeolites to remove mercury, mercury compounds and polyhalogenated hydrocarbons pollutants from the exhaust gas. The naturally occurring zeolites have a median particle size (d.sub.50) from 5 to 50 micrometers and the gas-solids suspension has a mean suspension density from 0.020 to 10 kg of solids per sm.sup.3 of exhaust gas. The mixture contains from 10 to 20% by weight mordenite, from 60 to 70% by weight clinoptilolite, from 0 to 5% by weight montmorillonite and a remaining balance of SiO.sub.2. The purified gas contains <50 micrograms of mercury per sm.sup.3, <0.1 ng TE per sm.sup.

Abstract: Toxic metal vapor phase compounds, and in particular, mercury and cadmium, are removed from waste incinerator combustion gases by contact with dry alkaline material and dry activated carbon followed by solids separation. The resulting gas is subjected to quench/wet scrubbing with recycle hydrochloric acid solution formed in situ by absorption of HCl from the gas. Blowdown liquid withdrawn from the recycle acid liquor, may be recycled to the incinerator or further treated by neutralization, precipitation, and filtration of the precipitated toxic metals.

Abstract: A method for removing pollutants from a combustor flue gas. The method includes the steps of supplying sorbent to a baghouse having a filter bag therein until the filter bag is coated with a predetermined amount of sorbent and introducing the flue gas into the baghouse. Pollutants in the flue gas are sorbed by the sorbent on the filter bag. A system is provided for performing the method of the invention.

Abstract: Ceramic particles impregnated with silver nitrate for adsorbing mercury from waste gases can be regenerated and reused if the mercury is distilled off at 600.degree. to 900.degree. C. and the ceramic particles are subsequently impregnated with nitric acid.

Abstract: A regenerative mercury removal process for simultaneously removing high mercury and water content from a fluid comprising; contacting for a sufficient time a high content mercury-containing fluid with an adsorbent bed having sufficient silver coated or impregnated thereon to remove therefrom substantial amounts of mercury and water; regenerating the adsorbent using a regenerative gas and condensing-out and recovering the mercury to yield a fuel substantially free from mercury.

Abstract: A process for producing low mercury coal during precombustion procedures by releasing mercury through discriminating mild heating that minimizes other burdensome constituents. Said mercury is recovered from the overhead gases by selective removal.

Abstract: Mercury is often removed as an impurity from process fluid streams by adsorption in fixed beds using any of several well-known adsorbents having the ability to selectively adsorb mercury. It is also common to reintroduce this sequestered mercury into the environment by means of the spent gas used to periodically regenerate the fixed beds. A solution to this problem is provided by the present invention in which the mercury is removed from the process stream using a large cyclically regenerated adsorption bed in combination with a non-regenerable secondary adsorption bed, the mercury content of the former being in part recovered as liquid mercury by passage through a condenser and in part transferred to the non-regenerated bed. Mercury leakage from the non-regenerable bed is recycled to the cyclically regenerated bed.

Abstract: A scrubber for industrial exhaust systems advantageously employs liquid gallium to adsorb vapor phase mercury as well as sub-micron sized particulates such as other trace metal constituents from a hot gas exhaust stream in an industrial exhaust system. The temperature of the liquid gallium is elevated for optimum adsorption efficiency, and subsequently lowered to separate the adsorbed mercury and other species.

Abstract: A solid mass for the recovery of mercury, comprising a solid mineral support or dispersant, essentially copper and sulphur at least partly in the form of copper sulfide is produced by the following stages:a) at least one copper compound other than a sulphide is incorporated into a solid mineral dispersant or carrier,b) the product obtained in stage (a) is calcined in order at least partly to convert the copper compound or compounds which it contains into copper oxide (CuO and/or Cu.sub.2 O),c) the product obtained in stage (b) or in stage (a) if there has not been a stage (b) is brought into contact with elementary sulphur,d) the product resulting from stage (c) referred to as the precursor, is subjected to a thermal treatment in a non-oxidizing atmosphere and accompanied by gas scavenging, to a temperature and for a sufficient time to allow the formation of sulphide of the metal(s) present.

Abstract: An adsorption system, such as a composite drier-bed, having at least two distinct adsorption regions for simultaneously drying and removing metallic/inorganic and organic forms of mercury from a fluid including a container having an entrance area and an exit area; a distinct first region located within said container and proximal to said entrance area of a porous substrate having elemental silver associated therewith; and a distinct second region adjacent thereto of a porous substrate having elemental gold associated therewith. The first region substantially removes water and metallic forms of mercury and the second region substantially removes organic forms of mercury and residual water from said fluid. A method of removing both metallic and organic mercury simultaneously with water as well as a means for regenerating the drier-bed is also disclosed.

Abstract: In processes for removing mercury vapor from natural gas streams by selective adsorption in fixed adsorbent beds, water is invariably adsorbed along with the mercury impurity. During the periodic purge regeneration of the adsorbent bed it is desirable to recover as much as possible of the desorbed mercury in the spent regeneration gas in liquid form to avoid reintroducing the mercury into the environment. Cooling this spent regeneration gas under the high pressure conditions involved to condense the mercury can result in the highly undesirable formation of hydrocarbon hydrates if temperatures low enough to condense an adequate amount of mercury are employed. In the process of the present invention, the spent regeneration gas stream, from which some mercury has been removed by cooling, is further treated in a desiccant bed so that it is possible to cool it further in order to condense and remove additional mercury without encountering hydrocarbon hydrate formation.

Abstract: In the purification of natural gas streams to remove mercury by adsorption procedures, environmental pollution is avoided by using a condenser in conjunction with the adsorption beds in a manner such that the mercury vapor contained in the purge gas used to regenerate the adsorption beds is covered entirely as a liquid rather than being vented from the purification system as mercury vapor.

Abstract: Mercury is often removed as an impurity from process fluid streams by adsorption in fixed beds using any of several well-known adsorbents having the ability to selectively adsorb mercury. It is also common to reintroduce this sequestered mercury into the environment by means of the spent gas used to periodically regenerate the fixed beds. A solution to this problem is provided by the present invention in which the mercury is removed from the process stream using at least two cyclically regenerated adsorption beds in combination with a condenser whereby upon regeneration of one bed, the regeneration stream effluent therefrom is treated in the condenser to recover the bulk of the mercury as liquid mercury and recycling the overhead from the condenser to another bed engaged in the adsorption-purification of fresh feedstock.

Abstract: In this method and this apparatus exit gases to be purified from kiln installations are first of all dedusted in a first filter stage and then in at least one further filter stage they are purified of the NH.sub.x compounds and/or volatile pollutant elements and compounds with at least partial reduction of NO.sub.x with the aid of a carbonaceous filter medium. In order that the filter dust precipitated in the first filter stage can without problems either be re-used in a suitable manner of deposited in simple refuse dumps, the proportion of low-boiling pollutants and pollutant compounds in this precipitated filter dust is reduced by successive method steps in which the said pollutants are evaporated out of the filter dust, the quantities of dust are precipitated out of these vapors and the dedusted vapours are passed through a filter unit containing a carbonaceous filter medium.

Abstract: The invention relates to a method of eliminating mercury or arsenic from a fluid in the presence of a solid mass for the recovery of mercury and/or arsenic. The said mass contains copper and sulphur at least partly in the form of copper sulphide and results (a) from the incorporation of a copper compound other than a sulphide into a solid mineral support, (b) possible calcination of the product obtained in stage (a), and from bringing the product obtained previously into contact with elementary sulphur and (d) a heat treatment.