Abstract: Exhaust gas cleaning equipment including a gas scrubber and a scrubber fluid cleaning equipment for cleaning polluted scrubber fluid. The scrubber fluid cleaning equipment includes a centrifugal separator for separating at least a pollutant phase and a cleaned scrubber fluid from said polluted scrubber fluid. The centrifugal separator has a rotor enclosing a separation space with a stack of separating discs, a separator inlet for polluted scrubber fluid extending into said separation space, a first separator outlet for cleaned scrubber fluid extending from said separation space, and a second separator outlet for the pollutant phase extending from said separation space.

Abstract: Reactive diluent fluid (22) is introduced into a stream of synthesis gas (or “syngas”) produced in a heat-generating unit such as a partial oxidation (“POX”) reactor (12) to cool the syngas and form a mixture of cooled syngas and reactive diluent fluid. Carbon dioxide and/or carbon components and/or hydrogen in the mixture of cooled syngas and reactive diluent fluid is reacted (26) with at least a portion of the reactive diluent fluid in the mixture to produce carbon monoxide-enriched and/or solid carbon depleted syngas which is fed into a secondary reformer unit (30) such as an enhanced heat transfer reformer in a heat exchange reformer process. An advantage of the invention is that problems with the mechanical integrity of the secondary unit arising from the high temperature of the syngas from the heat-generating unit are avoided.

Abstract: An emission gas treatment apparatus recovers a recycle feed containing boron from emission gas discharged by a glass melting furnace. The apparatus includes a collection device for collecting a component containing boron from the emission gas by a wet process to obtain a collected liquid, a first filter for separating the collected liquid into a solid and a liquid, and an ion-exchange resin for forming a boron solution by removing an impurity from an extracted liquid obtained in the first filter. The apparatus also includes a mixing tank for mixing an extracted solid obtained in the first filter in the boron solution to form an extracted solid-containing solution, a second filter for separating the extracted solid-containing solution into a solid and a liquid, and a vacuum dryer for recovering the recycle feed from an extracted solid obtained in the second filter.

Abstract: A device and method for separating off carbon dioxide is provided, including an absorption unit, desorption unit assigned thereto and a separation unit for separating off salts from a scrubbing solution. The absorption and desorption units are connected to each other via a first conduit for a regenerated scrubbing solution and a second conduit for a loaded scrubbing solution. The separation unit includes a crystallizer for forming salt crystals and a first separator unit on the downstream side for separating off salt crystals. A separation unit is provided for separating off salts from a scrubbing solution, having a crystallizer and a first separator unit downstream thereof. The crystallizer has a crystallization chamber for forming salt crystals and a countercurrent classifier for separating salt crystals according to particle size. A first branch conduit is connected to the crystallization chamber, which opens out into the countercurrent classifier via a second separator unit.

Abstract: Methods for removing sulfur from a gas stream prior to sending the gas stream to a gas separation membrane system are provided. Two schemes are available. When the sulfur content is high or flow is relatively high, a scheme including two columns where one tower is regenerated if the sulfur concentration exceeds a preset value can be used. When the sulfur content is low or flow is relatively low, a scheme including one column and an absorption bed.

Abstract: The object of the invention is a method for dissolving carbon dioxide from flue or other gas and for the neutralization of the solution obtained. The gas, in which the partial pressure of carbon dioxide is at least 0.4 bar, is led to a dissolution process, where the major part of the carbon dioxide is dissolved into a flow of water. The aqueous solution of carbon dioxide thus obtained is neutralized by passing it through a material containing feldspar minerals, at which time the hydrogen ions of said solution are replaced by ions of alkali or alkaline earth metals, and the aluminum in said material is converted into aluminum compounds that can be separated and utilized.

Abstract: A method for removing elemental sulfur from a hot gas stream, such as an autoclave vent gas, while simultaneously cooling the gas stream. The method results in conversion of sulfur in the hot gas stream to the form of solid, non-sticky sulfur allotropes such as rhombic sulfur while avoiding formation of sticky sulfur allotropes such as monoclinic sulfur, thereby avoiding scaling and fouling of plant equipment. According the method, the hot gas stream is contacted with an aqueous medium containing a particulate material inside a quench vessel having a first inlet for the hot gas stream, a second inlet for the aqueous medium, and an outlet for removing a sulfur-containing liquid fraction from the vessel. At least a portion of the sulfur contained in the hot gas stream, along with other condensable materials, becomes incorporated into the aqueous medium and is subsequently drained from the vessel.

Abstract: A method for treating a process gas with a liquid comprises contacting a process gas with a hygroscopic working fluid in order to remove a constituent from the process gas. A system for treating a process gas with a liquid comprises a hygroscopic working fluid comprising a component adapted to absorb or react with a constituent of a process gas, and a liquid-gas contactor for contacting the working fluid and the process gas, wherein the constituent is removed from the process gas within the liquid-gas contactor.

Abstract: The invention relates to a process and an apparatus for optimized combination of purification and separation of MTO reaction gas containing catalyst fine powder.

Abstract: A method of mixing an oxygen gas with a hydrocarbon-containing gas includes the steps of wet scrubbing the oxygen gas in a wet scrubber, supplying oxygen gas from the wet scrubber to a gas mixer and mixing the oxygen gas with the hydrocarbon-containing gas in the gas mixer. Wet scrubbers for use in the method may take various forms, including packed-tower, bubble cap, and sparger-type wet scrubbers. The removal of the particulate matter reduces the risk of ignition of the hydrocarbon-containing gas in the gas mixer. The use of a wet scrubber in the oxygen supply line overcomes many problems currently faced with screen and filters, as per current practice.

Abstract: The present invention relates to a method of deacidizing a gaseous effluent, wherein the following stages are carried out: a) contacting the gaseous effluent with an absorbent solution so as to obtain a gaseous effluent depleted in acid compounds and an absorbent solution laden with acid compounds, the absorbent solution being selected for its property to form two separable phases when it absorbs an amount of acid compounds, b) separating the absorbent solution laden with acid compounds into two fractions: a first absorbent solution fraction depleted in acid compounds and a second absorbent solution fraction enriched in acid compounds, c) regenerating the second fraction so as to release part of the acid compounds, d) mixing a predetermined amount of water with the first absorbent solution fraction obtained in stage b) or with the regenerated absorbent solution fraction obtained in stage c), then e) recycling the first absorbent solution fraction and the regenerated absorbent solution as the absorbent solu

Abstract: A water recovery method which uses a desiccant, such as lithium chloride, to recover water vapor from the engine exhaust of a vehicle.

Abstract: An ammonia based CO2 capture system and method is provided in which multiple absorption stages are provided. Each absorption stage delivers an ionic solution at a predetermined temperature and contacts it with a flue gas stream.

Abstract: A solution contained in a regeneration tower is supplied to a filtering unit. The filter unit filters out solid particles contained in the solution. A washing unit washes out with backwash water solid particles filtered out by the filter unit. An evaporating unit receives the backwash water containing the solid particles, and heats received backwash water thereby obtaining solid-particles concentrated backwash water.

Abstract: Disclosed is a method of removing carbon dioxide from a process gas, the method comprising: contacting an ammoniated solution with the process gas in an absorption arrangement 101, the ammoniated solution capturing at least a part of the carbon dioxide of the process gas, wherein the molar ratio, R, of ammonia to carbon dioxide in the ammoniated solution is controlled such that substantially no precipitation of solids occurs within the absorption arrangement 101; allowing ammoniated solution including captured carbon dioxide to exit the absorption arrangement 101; cooling the ammoniated solution that has exited the absorption arrangement, wherein at least a part of the captured carbon dioxide is precipitated as solid salt; separating at least a part of the precipitated salt from the ammoniated solution; heating the ammoniated solution from which the at least a part of the precipitated salt has been separated, such that substantially no solids are present in the heated ammoniated solution; and allowing the hea

Abstract: Two methods are provide for the separation of carbon dioxide from the flue gases. The first method utilizes a phase-separating moiety dissolved in an aqueous solution of a basic moiety to capture carbon dioxide. The second method utilizes a phase-separating moiety as a suspended solid in an aqueous solution of a basic moiety to capture carbon dioxide. The first method takes advantage of the surface-independent nature of the CO2 absorption reactions in a homogeneous aqueous system. The second method also provides permanent sequestration of the carbon dioxide. Both methods incorporate the kinetic rate enhancements of amine-based scrubbing while eliminating the need to heat the entire amine solution (80% water) in order to regenerate and release CO2. Both methods also take advantage of the low-regeneration temperatures of CO2-bearing mineral systems such as Na2CO3/NaHCO3 and K2CO3/KHCO3.

Abstract: Production brines are used to scrub a horizontal stack receiving exhaust from an energy source, controlling, reducing, or both noxious chemicals. Mutual remediation of flows from petroleous production cool and scrub exhausts from flares burning waste hydrocarbons, heaters lowering viscosity of crude oil, engines driving oil pumps or natural gas compressors, and the like. Resulting evaporation of production brines results in distilled water, more concentrated brines to reduce hauling, or, optionally, dehydrated dry waste minerals from the brines. Year-round operation of brine evaporation ponds is facilitated, and may be another source of process pre-heating.

Abstract: Reactive diluent fluid (22) is introduced into a stream of synthesis gas (or “syngas”) produced in a heat-generating unit such as a partial oxidation (“POX”) reactor (12) to cool the syngas and form a mixture of cooled syngas and reactive diluent fluid. Carbon dioxide and/or carbon components and/or hydrogen in the mixture of cooled syngas and reactive diluent fluid is reacted (26) with at least a portion of the reactive diluent fluid in the mixture to produce carbon monoxide-enriched and/or solid carbon depleted syngas which is fed into a secondary reformer unit (30) such as an enhanced heat transfer reformer in a heat exchange reformer process. An advantage of the invention is that problems with the mechanical integrity of the secondary unit arising from the high temperature of the syngas from the heat-generating unit are avoided.

Abstract: A method of removing elemental mercury from gas phase fluids by contacting the gas with an organic compound dissolved in a gas scrubbing liquid.

Abstract: A solid is separated from a gas scrubber by collecting a solids burden not collected at a solids-collection device of a flue gas desulfurization system by adding at least one flocculant, flocculation aid or mixtures thereof, while using a separating device; wherein te flue-gas desulfurization system contains at least one absorption device disposed downstream from said solids-collection device.

Abstract: The present invention discloses a system for flue gas treatment, wherein the provided system comprises a quench module, a first control module, a filter collecting module, a wet scribing module and a regeneration module. In this system, parts of the particles contained in flue gas are removed in the quench module and the wet scribing module by a first scrubbing solution, and then in wet scribing module a second scrubbing liquid containing particles is formed. Next, the second scrubbing solution is treated in the regeneration module to form a third scrubbing solution, wherein the third scrubbing solution is then fed back to the quench module and/or the wet scrubbing module to substitute the first scrubbing solution for repeating what originally performed via the first scrubbing solution. Furthermore, this invention discloses a method for flue gas treatment.

Abstract: A buoyant component separator is disclosed for removing at least some floating contaminants from fluids. The component separator may be used with a marine engine exhaust system to reduce particulate matter and unburned fuel contained in liquid coolant before it is jettisoned overboard and pollutes the surrounding body of water. In one embodiment, the separator includes a first part for receiving a mixture of liquid and buoyant components and a second part joined by a communication passage, where the liquid flows through the communication passage to the second part and the buoyant components substantially accumulate in the first part. A method of separating a liquid from buoyant components is also provided.

Abstract: Methods are provided for the selective removal of CO2 from a multicomponent gaseous stream to provide a CO2 depleted gaseous stream. In practicing the subject methods, an initial multicomponent gaseous stream is contacted with an aqueous fluid under conditions of selective CO2 clathrate formation to produce a CO2 clathrate slurry and CO2 depleted gaseous stream. A feature of the subject methods is that the CO2 clathrate slurry is then compressed to high pressure to produce a high-pressure CO2 product. Also provided are systems that find use in practicing the subject methods. The subject methods and systems find use in a variety of applications where it is desired to selectively remove CO2 from a multicomponent gaseous stream.

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: A scoop is used to collect a liquid slurry upstream of an internal collection tank. The scoop is in fluid communication with a downcomer, which receives at least part of the collected slurry, thereby maintaining a continuous flow of liquid slurry through the scoop to prevent plugging. Collected slurry can be removed for treatment from the scoop or the downcomer. In an application to a wet flue gas desulfurization (FGD) scrubber, the scoop collects an effluent slurry of partially reacted liquid scrubbing reagent and scrubbing byproducts before they drain into an internal reaction tank. Partially reacted liquid scrubbing reagent and scrubbing byproducts can therefore be withdrawn for treatment before the addition of fresh reagent alters the pH of the treatment stream.

Abstract: A method of removing hydrogen sulphide from a gas stream wherein the hydrogen sulphide is scrubbed from the gas phase by an aqueous solution, the hydrogen sulphide in the aqueous solution is biologically oxidized in a bioreactor to produce elemental sulphur, and the elemental sulphur is separated from the aqueous solution, characterized in that the gas stream to be treated is cooled to such a degree that at least sufficient water vapour condenses from the gas stream to compensate for the discharge stream for the purpose of removing salts. This means that no water need be supplied to the bioreactor. This method is suitable, in particular, for gas streams which contain hydrogen sulphide, the hydrogen sulphide having been obtained by catalytic conversion of sulphur compounds.

Abstract: A process and system for producing fertilizers with reduced levels of contaminants, and particularly a flue gas scrubbing process and facility that produce a fertilizer byproduct which is treated to remove heavy metals originally present in the scrubbed flue gas. The process entails contacting a flue gas with a scrubbing solution to remove acidic gases and produce a byproduct containing a fertilizer compound precipitate and dissolved metals and/or metal compounds. A fertilizer solution containing dissolved fertilizer and dissolved metals and/or metal compounds is then produced by adding water to the byproduct, after which the pH of the fertilizer solution is adjusted one or more times with a gaseous and/or liquid alkali to form precipitates of one or more metal species. The precipitates are then removed from the fertilizer solution and the solution dewatered to yield a fertilizer product with lower contaminant levels.

Abstract: Disclosed is a method of removing heavy metals contained in exhaust gas which has been generated by burning a waste liquid containing the heavy metals discharged in a process of producing organic compounds. The method includes the steps in the order of: (a) a combustion step of burning the waste liquid to produce exhaust gas; (b) a gas-liquid contact step of rendering a liquid containing an alkali compound in contact with the exhaust gas to collect the heavy metals in bottoms of the liquid; and (c) a coagulating step of adding a coagulant to the bottoms to coagulate the heavy metals in the bottoms for removal of the heavy metals. According to this method, the heavy metals contained in the exhaust gas can be efficiently separated and removed.

Abstract: In accordance with the present invention, a basic material, preferably ammonia, is injected into the stream of soot water leaving the gasification reactor prior to being processed in a filtration-type soot removal unit. The elevated pH of the soot water causes more metals to remain in the filter cake. Thus, the metals content of the grey water is reduced. More grey water can then be recycled back to the gasification unit, with less grey water being handled by the wastewater treatment unit.

Abstract: There is provided a heavy oil fired boiler exhaust gas treatment apparatus which removes soot and dust and SO3 in the heavy oil fired boiler exhaust gas efficiently at a low cost without using an excessively large apparatus. The treatment apparatus comprises a charging device 3 provided at the inlet of an absorption tower of a wet type exhaust gas desulfurizer 4 and neutralizer pouring means A provided on the upstream side of the charging device 3 to pour a neutralizer into exhaust gas and neutralize SO3 in the exhaust gas.

Abstract: A system and process for agglomerating and processing carbonaceous fines is provided. The process includes powdering the carbonaceous fines, mixing the powdered carbonaceous fines with an organic liquid creating a slurry, adding a predetermined amount of an aqueous electrolyte to the slurry creating agglomerated particles, settling the large agglomerated particles resulting in a settled mixture of agglomerated coal fines and reagent liquor, and separating the agglomerated coal fines from the reagent liquor.

Abstract: A scrubber system is provided which enables a substantially horizontal flow path for the gas which is being subjected to scrubbing. Among other advantages, this permits operation of the absorber with a differential pressure of zero or less. Scrubber composition spray means are positioned in the horizontal gas flow path for spraying an aqueous scrubber composition in a direction which is generally cocurrent with said gas flow. The system is free of means which spray the scrubber composition in directions countercurrent to said gas flow.

Abstract: A system and process for agglomerating and processing carbonaceous fines is provided. The process comprises powdering the carbonaceous fines, mixing the powdered carbonaceous fines with an organic liquid creating a slurry, adding a predetermined amount of an aqueous electrolyte to the slurry creating agglomerated particles, settling the large agglomerated particles resulting in a settled mixture of agglomerated coal fines and reagent liquor, and separating the agglomerated coal fines from the reagent liquor.

Abstract: A method is disclosed for recovering germanium from a gaseous mixture which includes a germanium-containing compound in vapor or particulate form, acid in vapor form, and water vapor. The gaseous mixture is contacted with a liquid containing water under conditions effective to dissolve the germanium-containing compound in the liquid. The acidity of the resulting liquid mixture is increased under conditions effective to vaporize the germanium-containing compound. The vaporized germanium-containing compound is contacted with one or more aqueous solutions under conditions effective to dissolve and precipitate the germanium-containing compound in at least one of the one or more aqueous solutions, and the resulting precipitate is separated from the at least one of the one or more aqueous solutions. The methods described herein are particularly well suited for recovering germanium from the waste gases produced during optical waveguide manufacturing processes.

Abstract: Method for purifying gas loaded with dust particles of various sizes, which method comprises the following steps:

Abstract: The dust concentration of the flue gas leaving an electrostatic precipitator and introduced into an absorption tower of a desulfurizer is adjusted to a level of 100 to 500 mg/Nm.sup.3. At the same time, a dust slurry having a higher dust concentration is separated and withdrawn from the slurry within the aforesaid absorption tower, and then subjected to a solid-liquid separation treatment. Thus, solid matter containing dust at a high concentration is extracted and discharged out of the system of the desulfurizer.

Abstract: A process is disclosed for treating the scrubbing water from the gas scrubbing process in an iron ore reduction plant. The scrubbing water is brought into direct contact with the gas in two gas scrubbers arranged in two successive scrubbing stages at the gas-side, is withdrawn from the gas scrubbers and is supplied again to the gas scrubbers after the solids it contains are separated, and after it is treated and cooled. The scrubbing water is separately withdrawn from the two scrubbing stages and only the scrubbing water from the first scrubbing stage is largely freed from solids in a thickener, then led into a warm water container. The scrubbing water from the second scrubbing stage is directly led into a return water container in which it releases carbon dioxide-rich flash gas led into the scrubbing water in the warm water container to enrich it with carbon dioxide.

Abstract: Sulfur oxides (SO.sub.x) are scrubbed from combustion effluents with economies in capital and operating costs by virtue of an arrangement of spray header piping and nozzles which permits ease of access for service with reduced spacing (e.g., 0.5 to 1.25 meters) between spray levels. At least two spray levels in a spray zone include a plurality of spray header pipes arranged parallel to the other spray header pipes within a spray level and vertically parallel to spray header pipes in at least one adjacent spray level. Each of the spray levels includes a plurality of spray nozzles extending from said spray headers. A majority of nozzles in a reference spray level are positioned such that lines drawn between them form a pattern of squares with the nozzles located at the corners of the squares. And, a majority of nozzles in an adjacent spray level are positioned over the centers of squares defined by four nozzles in the reference spray level.

Abstract: A process for reducing iron containing contaminants from a process stream of amine used for acid gas stripping by passing the process stream of amine adjacent a magnet sufficient to extract at least a portion of the iron containing contaminants from the process stream of amine, and an apparatus for removing iron containing contaminants from a process stream of amine used to strip acid gases from said amine in a cyclic flowpath having a main source of a process stream of amine, a conduit for containing the flow of a slipstream of the main source of the process stream of amine, a magnet adjacent the conduit sufficient to extract at least a portion of the iron containing contaminants from the process stream of amine, a filter for removing particulates from the slipstream upstream of the magnet, a filter for removing particulates from the slipstream downstream of the magnet, and a conduit for returning the slipstream to the main source of a process stream of amine with a reduced iron containing contaminant conten

Abstract: A method and an apparatus for cleaning a gas containing pollutants, such as hydrogen chloride and heavy metals, are described. The polluted gas (2) is contacted with an aqueous washing liquid (3) in a scrubber (1), whereupon part of the washing liquid is preevaporated in a preevaporation unit (7) to form a hydrochloric-acid-containing top fraction, which is essentially free from heavy metals, and a bottom fraction containing hydrochloric acid and heavy metals. Part of the bottom fraction is recirculated (15) for renewed preevaporation, while the remainder of the bottom fraction is treated (16) to remove any heavy metals present. The top fraction from the preevaporation is distilled in a rectification unit (22) to form a top fraction (31) and a bottom fraction (35).

Abstract: In a paint spray booth wherein water is used to collect oversprayed paint, a process is disclosed for detackifying and coagulating oversprayed paint by the independent and concurrent addition of specific amounts of specific anions and cationic polymers to the water system.

Abstract: A composition for reclaiming paint and volatile organic paint carrier from industrial paint spray booths without increasing VOCs has been developed. The improvement over the existing booths recirculating hydrophilic based fluids, is the inclusion of a water based solution containing about 10 to about 45 per cent by weight of one or more N-alkyl pyrrolidones, about 15 to 40 percent by weight of one or more alkyl glycol mono alkyl ethers, a surfactant present in the amount of about 0.1 to 2.0 percent by weight, and the balance water.

Abstract: A scrubbing tower and process for flue-gas desulfurization uses a device for introducing additives like lime and limestone to the reaction zone of the scrubber by feeding those additives to a recirculating system recirculating the liquid through the sump. The recirculating system can also be used to withdraw the suspension from the column whose sump is cylindrical with a flat bottom. Recirculated liquid is introduced close to this bottom by the recirculating pump.

Abstract: A method for converting a double-loop flue gas desulfurization system to a single-loop desulfurization system includes removing the deep packing from the scrubber housing and replacing the packing with a thin tray having a plurality of perforations. The return line which connects the bowl is removed from the feed tank; and a plurality of openings, apertures or perforations are provided in the shroud ring and the bowl of the housing in order to permit slurry to pass from upper spray headers to the bottom of the housing as well as permit flue gas flow upwardly through the housing to the flue gas outlet. The lower spray headers are removed from the housing and the feed line connected to the lower spray headers is reconnected to the feed tank for providing the single-loop. An oxidation air system is provided in the feed tank for creating an in-situ forced oxidation system.

Abstract: A method and apparatus for recycling the bottoms product from an absorber tower back to the absorber tower. However, before the bottoms product is returned to the tower, the solid particles entrained therein are removed via one or more centrifuges closely coupled to the absorber tower. These centrifuges are located adjacent the tower and are elevated with respect to the tower such that their centrate can be directly returned or delivered back to the absorber tower via gravity.

Abstract: An apparatus and method for removing pollutants from a gas stream wherein a spray of steam is directed against a primary deflector plate to disperse a portion of the spray and repel the spray off of the primary deflector plate against a secondary deflector plate to disperse at least a portion of the spray rebounded against the secondary deflector plate, the placement of the primary deflector plate and secondary deflector plate adapted such that the dispersed spray from the primary and secondary deflector plates forms an aerosol in the path of the gas stream, allowing the aerosol to condense into water, and recovering the condensed water.

Abstract: A flue gas desulfurization process wherein the liquid bottoms product from the scrubber tower is subject to forced oxidation in a reaction/oxidation tank. Afterwards, this oxidized bottoms product is delivered to hydroclone means for separation into an overflow stream containing an aqueous slurry of mostly fines, fly ash, and unused reagent and an underflow stream containing predominately a gypsum slurry. The overflow stream is initially recycled back to the tank with another stream being subsequently returned or recycled back to the scrubber tower while the underflow stream is dewatered for the removal of the gypsum therein.

Abstract: The present invention relates to a novel method for coagulating waterborne paints in paint spray booth recirculating water. The coagulant aid comprises a polynucleate hydroxy silicate-sulphate compound (hereinafter PASS) having the following average composition of the general formula:Al(OH).sub.B (SO.sub.4).sub.C (SiO.sub.X).sub.D (H.sub.2 O).sub.Ewherein B ranges from 0.75 to 2.0; C ranges from 0.30 to 1.12; D ranges from 0.005 to 0.1; X is greater than 2.0 but less or equal to 4.0 such that3=B+2C+2D(X-2)E is 1.5 to 4 when the product is in solid form; and E is larger than 4 when the product is in aqueous form, which may optionally be used together with alum or a mixture of alum and a polyamine. The coagulant aids of this invention may also be used advantageously with detackifying agents to simultaneously detackify and coagulate solvent based paint particles.