Abstract: A gas scrubber and a waste gas treatment system with a gas scrubber for removing particles from a waste gas has a housing with a waste gas inlet and a waste gas outlet. A substantially circular plate member defining an axis of rotation is rotatably arranged in the housing. Waste gas fed into the housing via the waste gas inlet is directed toward approximately the center of the circular plate member. An outlet nozzle sprays a liquid, especially a cleaning liquid or a scrubbing liquid, onto the circular plate member, in order to obtain a mixture of waste gas and liquid in front of the plate member. A combination of inner and outer rotor arrays, and inner and outer stator arrays are arranged alternatingly and concentrically relative to each other, and separated from the circular plate member, and rotate about the axis of rotation. A rotary atomizer for atomizing the mixture of waste gas and liquid may be arranged on the circular plate member. Particles from the waste gas stream are transferred into the liquid.

Abstract: A method for producing aqueous hydrochloric acid from flue gases is provided. The method comprises conveying water to a first scrubber (102, 202, 302, 402, 502, 602, 702) or to a line (112b, 212b, 312b, 412b, 512b, 712b, 712c) to use the water in a scrubbing liquid of the first scrubber. The method also comprises providing flue gas containing chlorides into the first scrubber (102, 202, 302, 402, 502, 602, 702) and scrubbing the flue gas containing chlorides with the scrubbing liquid by contacting the flue gas with the scrubbing liquid in the first scrubber (102, 202, 302, 402, 502, 602, 702). Dilute hydrochloric acid and a flue gas derivate (104, 204, 304, 404, 504, 704) are produced.

Abstract: A method of removing contaminants from a gas stream utilizing a supersonic venturi including a converging section, a throat, and a diverging section is provided. A contaminated gas stream and a scrubbing liquid stream are introduced into the converging section, thereby forming a mixed stream which experiences choked flow upon exiting. The choked mixed stream is introduced into the throat section wherein the scrubbing liquid is contacted with the contaminated gas stream. The contaminated scrubbing liquid stream is removed from the supersonic venture scrubber, and an essentially pure gas stream is removed from the diverging section. A flow modification device may be introduced into the throat section. The flow modification device may be either axially or radially adjustable in order to effect the atomization of the scrubbing liquid and/or the contacting of atomized scrubbing liquid with the contaminated gas stream within the throat section.

Abstract: A two stage scrubber process for ethanol fermentation has a first stage using fusel oil to remove the hazardous air pollutants and recover the majority of the ethanol. A second stage uses water as the scrubbing solvent to recover any residual ethanol that is stripped from the first stage.

Abstract: A method and apparatus or system is provided for cleaning a flue gas and/or cooling a flue gas with a dispersed finely divided absorption liquid. As such, the absorption liquid is dispersed in a wet scrubber through which flue gas flows for absorption liquid and flue gas intermingling and contact to produce a cleaned flue gas. The absorption liquid supplied to the wet scrubber is dispersed from upwardly spraying anti-clogging nozzles and downwardly spraying nozzles arranged to maximize absorption liquid and flue gas contact with minimal spray interference between nozzles.

Abstract: An improved method for the removal of non-targeted components from a non-targeted component containing gas stream, the method includes the steps of: (i) contacting the non-targeted component containing gas stream with a fluid solvent stream; (ii) passing the product of step i) through a co-current phase separation step to produce both a non-targeted component containing solvent stream and a partially purified gas stream; (iii) passing the partially purified gas stream product of step ii) through a mass transfer step to produce a wet gas product; and (iv) passing the wet gas product of step iii) through a final co-current phase separation step to produce a purified gas stream, wherein the method is performed in a subsea location.

Abstract: Heat is removed from a process liquid of a direct contact condenser in waste gas cooling using two separate and distinct cooling devices that provide cooled process liquid to at least two separate sections in the direct contact condenser. Most preferably, the sections are liquidly isolated and provide the heated process liquids to the respective cooling devices. However, in other embodiments, the sections are liquidly coupled to each other so to allow transfer of the process liquid from one section to another section. One of the two cooling devices uses a lower-cost or higher-availability coolant that the other. It is generally preferred that one of the cooling devices is an air cooler and that another one of the cooling devices employs a cooling medium other than air.

Abstract: The invention relates to a device and method for treating a hot gas flow containing slag and to an entrained-bed gasifier system that comprises the device. The device comprises, in a housing, an inlet arranged at the top for the hot gas flow, an immersion pipe, which is arranged vertically and concentrically in the housing and into which the inlet opens, a coolant bath, into which a lower section of the immersion pipe is immersed, and at least one raw gas outlet opening for cooled raw gas that has been freed of slag. The lower section of the immersion pipe is designed as a radially expanded gas distributor bell in the coolant bath. Said gas distributor bell is formed by a substantially conical jacket surface having a cross-section that expands downward, wherein the jacket surface has a plurality of gas passage openings, which are distributed over the circumference of the gas distributor bell. The dimensions of the gas passage openings increase with the immersion depth in the coolant bath.

Abstract: The invention generally relates to a method for sequestration contaminates. More particularly, the invention relates to a significant performance enhancement over existing mineral carbonation processes through the use of a high mass transfer system and an efficient pH swing reaction. More particularly, aspects of the invention are directed to direct and indirect methods of sequestering contaminates.

Abstract: A modular ductwork assembly decontaminates an air stream circulating within a heating, ventilation and air conditioning (HVAC) system. The assembly includes one or more of (a) an ionizing module for removing particulates from the air stream, (b) a sterilization module for neutralizing airborne pathogens present in the air stream, (c) an ozone treatment module for neutralizing pathogens or odoriferous or gaseous constituents or volatile organic compounds (VOCs) present in the air stream, optionally (d) baffles for slowing and disrupting the flow rate and promoting turbulence in the air stream traveling through the modules, optionally (e) a fan module for directing a treated air stream, optionally (f) an ozone sensor, optionally (g) a monitoring or ozone control means, and optionally (h) a means of delivering and repurposing generated ozone. Each of the modules is arranged substantially adjacent to at least one of the other modules.

Abstract: A wet scrubber (1) and a method of using the wet scrubber to clean a process gas containing sulphur dioxide comprising at least one spray level system (20) with atomizing nozzles (38) to which an absorption liquid is supplied for atomization by the nozzles (38). The method comprises operating the spray level system (20) in at least a first operating mode with an active nozzle density of at least 0.7 nozzles/m2, an absorption liquid flow of at least 10 m3/hour per nozzle and a Total Flow of at least 30 m3/hour/m2.

Abstract: A wet scrubber (1) and a method of using the wet scrubber to clean a process gas containing sulphur dioxide comprising at least one spray level system (20) with atomizing nozzles (38) to which an absorption liquid is supplied for atomization by the nozzles (38). The method comprises operating the spray level system (20) in at least a first operating mode with an active nozzle density of at least 0.7 nozzles/m2, an absorption liquid flow of at least 10 m3/hour per nozzle and a Total Flow of at least 30 m3/hour/m2.

Abstract: The invention relates to a gas liquid contactor and effluent cleaning system and method and more particularly to individually fed nozzle banks including an array of nozzles configured to produce uniformly spaced flat liquid jets shaped to minimize disruption from a gas. An embodiment of the invention is directed towards a gas liquid contactor having a plurality of modules including a liquid inlet and outlet and a gas inlet and outlet. An array of nozzles is in communication with the liquid inlet and the gas inlet. The array of nozzles is configured to produce uniformly spaced flat liquid jets shaped to minimize disruption from a gas flow and maximize gas flow and liquid flow interactions while rapidly replenishing the liquid.

Abstract: A fractionation process for producing at least two concentration fractions of a fluid including a solute, suspended or dissolved content using at least two fluidly connected evaporator units is provided. The process includes the steps of: feeding a feed fluid including a solute, suspended or dissolved content into at least a first evaporator unit; evaporating a first amount of fluid from the feed fluid in at least the first evaporator unit to produce a first concentrated fluid; feeding at least a portion of the first concentrated fluid into at least a second evaporator unit; and evaporating a second amount of fluid from the first concentrated fluid in at least the second evaporator unit to produce a second concentrated fluid.

Abstract: A multi-stage scrubbing system comprises a pre-scrubber system structured to receive a vent stream therein and pre-scrub the vent stream with a pre-scrubber fluid. The pre-scrubber system includes a first outlet for discharging a pre-scrubbed vent stream and a second outlet for discharging a discharge stream of pre-scrubber fluid. A main scrubber system is fluidly coupled to the first outlet of the pre-scrubber system for receiving and further scrubbing the pre-scrubbed vent stream.

Abstract: Petroleous production is associated with effluents well known to foul lines, nozzles, and containers while consuming substantial energy to assist in both production and remediation. A heat exchanger and manifold system maximizes flows, minimizes changes in flow cross-section, and maximizes heat transfer area, while recycling both water and heat between processes. Dirty regions and clean regions result from scrubbing horizontal exhaust stacks and evaporation of production water in concert to remediate one another, while recycling a significant portion of the energy consumed by each. The heat exchanger relies on a manifold having many layered conduits, each connected to a single layer level of one or more cylindrical conduits in the exchanger. The cylinders of the exchanger themselves are arranged in multiple layers, each layer of a heat exchanger element being connected to a single layer of the manifold.

Abstract: A two phase reactor includes a source of liquid reactant and a source of gas reactant. A chamber has an inlet coupled to the source of gas reactant and a flat jet nozzle coupled to the source of the liquid reactant.

Abstract: The invention relates to a gas liquid contactor and effluent cleaning system and method and more particularly to an array of nozzles configured to produce uniformly spaced flat liquid jets with reduced linear stability. An embodiment of the invention is directed towards a stability unit used with nozzles of a gas liquid contactor and/or an enhancer for stable jet formation, and more particularly to reducing the stability of liquid jets formed from nozzles of the gas liquid contactor. Another aspect of the invention relates to operating the apparatus at a condition that reduces the stability of liquid jets, e.g., a droplet generator apparatus. Yet another aspect of the invention relates to operation of the apparatus with an aqueous slurry. Still another aspect of the invention is directed towards to an apparatus for substantially separating at least two fluids.

Abstract: An exhaust gas cleaning apparatus according to the present invention includes a wall member configured to form a gas passage for allowing an exhaust gas to pass therethrough, and a mist nozzle and a water film nozzle disposed in the gas passage. The mist nozzle forms mist in the gas passage, and the water film nozzle forms water film in the gas passage. The mist nozzle is disposed further toward the upstream side in a flowing direction of the exhaust gas than the water film nozzle. Plural sets of the mist nozzle and the water film nozzle may be provided.

Abstract: An FGD system is provided which can be retrofitted on existing utility coal-fired boilers. The design is based on a horizontal co-current scrubber capable of generating a pressure rise across the absorber. Modifications to existing plant equipment are minimized by the co-current horizontal scrubber design. The system includes features, which eliminate much equipment typically associated with other FGD designs, and reduces the use of support equipment such as tanks, agitators, and pumps. It also minimizes or eliminates the need for new buildings.

Abstract: The invention relates to a gas liquid contactor and effluent cleaning system and method and more particularly to an array of nozzles configured to produce uniformly spaced flat liquid jets with reduced linear stability. An embodiment of the invention is directed towards a stability unit used with nozzles of a gas liquid contactor and/or an enhancer for stable jet formation, and more particularly to reducing the stability of liquid jets formed from nozzles of the gas liquid contactor. Another aspect of the invention relates to operating the apparatus at a condition that reduces the stability of liquid jets, e.g., a droplet generator apparatus. Yet another aspect of the invention relates to operation of the apparatus with an aqueous slurry. Still another aspect of the invention is directed towards to an apparatus for substantially separating at least two fluids.

Abstract: The invention relates to a gas liquid contactor and effluent cleaning system and method and more particularly to an array of nozzles configured to produce uniformly spaced flat liquid jets with reduced linear stability. An embodiment of the invention is directed towards a stability unit used with nozzles of a gas liquid contactor and/or an enhancer for stable jet formation, and more particularly to reducing the stability of liquid jets formed from nozzles of the gas liquid contactor. Another aspect of the invention relates to operating the apparatus at a condition that reduces the stability of liquid jets, e.g., a droplet generator apparatus. Yet another aspect of the invention relates to operation of the apparatus with an aqueous slurry. Still another aspect of the invention is directed towards to an apparatus for substantially separating at least two fluids.

Abstract: An aerosol separator is arranged before a CO2 compressor to prevent wear and damage in CO2 recovery systems for the recovery of CO2 arising during fermentation using a compressor.

Abstract: The invention relates to a gas liquid contactor and effluent cleaning system and method and more particularly to an array of nozzles configured to produce uniformly spaced flat liquid jets shaped to minimize disruption from a gas. An embodiment of the invention is directed towards a gas liquid contactor module including a liquid inlet and outlet and a gas inlet and outlet. An array of nozzles is in communication with the liquid inlet and the gas inlet. The array of nozzles is configured to produce uniformly spaced flat liquid jets shaped to minimize disruption from a gas flow and maximize gas flow and liquid flow interactions while rapidly replenishing the liquid.

Abstract: Vapor-liquid contacting apparatuses, for example reactors and distillation columns (as well as reactive distillation apparatuses), comprising a vessel with one or more vortex contacting stages, are described. The one or more stages provide high interfacial area for the effective contacting of the different phases, in addition to the effective disengagement of these phases after contacting.

Abstract: A wet scrubber (1) and a method of using the wet scrubber to clean a process gas containing sulphur dioxide comprising at least one spray level system (20) with atomizing nozzles (38) to which an absorption liquid is supplied for atomization by the nozzles (38). The method comprises operating the spray level system (20) in at least a first operating mode with an active nozzle density of at least 0.7 nozzles/m2, an absorption liquid flow of at least 10 m3/hour per nozzle and a Total Flow of at least 30 m3/hour/m2.

Abstract: An inlet air chilling and filtration system for a turbine. The inlet air chilling and filtration system may include a first stage spray array with a first number of spray nozzle pairs, a second stage spray array with a second number of spray nozzles pairs, and a drift eliminator.

Abstract: The present invention relates to an air purifier employing a water jet-type fan system having a simple structure, in which water is pumped by a water pump and sprayed and scattered by the water jet-type fan system in which a plurality of spray nozzles are mounted on a fan having a flow channel, in order to purify contaminants. The fan system rotates by the principle of action and reaction using the spraying force of water. The air purifier of the present invention performs an air purification process and an air circulation function at the same time by spraying and scattering water so as to use the adsorption power of water, instead of using a motor fan for circulating air. The present invention also relates to a purification method of the air purifier.

Abstract: A modular scrubbing system is presented. The scrubber system comprises multiple modules that allow a gas flow to turn-around return back through scrubbing modules. Contemplated modules include inlets, outlets, turn-arounds, and scrubbing modules.

Abstract: A two phase reactor includes a source of liquid reactant and a source of gas reactant. A chamber has an inlet coupled to the source of gas reactant and a flat jet nozzle coupled to the source of the liquid reactant.

Abstract: The invention relates to a gas liquid contactor and effluent cleaning system and method and more particularly to an array of nozzles configured to produce uniformly spaced flat liquid jets with reduced linear stability. An embodiment of the invention is directed towards a stability unit used with nozzles of a gas liquid contactor and/or an enhancer for stable jet formation, and more particularly to reducing the stability of liquid jets formed from nozzles of the gas liquid contactor. Another aspect of the invention relates to operating the apparatus at a condition that reduces the stability of liquid jets, e.g., a droplet generator apparatus. Yet another aspect of the invention relates to operation of the apparatus with an aqueous slurry. Still another aspect of the invention is directed towards to an apparatus for substantially separating at least two fluids.

Abstract: A method and system for reducing an amount of ammonia in a flue gas stream. The system 100 includes: a wash vessel 180 for receiving an ammonia-containing flue gas stream 170, the wash vessel 180 including a first absorption stage 181a and a second absorption stage 181b, each of the first absorption stage 181a and the second absorption stage 181b having a mass transfer device 184; and a liquid 187 introduced to the wash vessel 180, the liquid 187 for absorbing ammonia from the ammonia-containing flue gas stream 170 thereby forming an ammonia-rich liquid 192 and a reduced ammonia containing flue gas stream 190 exiting the wash vessel 180.

Abstract: Aspects include a valve comprising a flowing liquid, operable to control a flow of gas through a port. Certain aspects include reaction chambers operable to react gases, and in some aspects gases are substantially contained within an envelope comprised of a flowing liquid. Certain embodiments control gas entrance into a chamber with a valve comprised of a flowing liquid controlling gas flow through a port. Various gas scrubbing systems are described, including systems comprising reaction chambers operable to react gases that yield substantial amounts of solid reaction products. Methods for controlling gas flow are disclosed. Systems and methods include sequential steps of wet-scrubbing, reacting and further wet-scrubbing a gas stream.

Abstract: In order to provide a phase detector and a method of phase detection which are distinguished by greater sensitivity and simple implementability, at least one differential signal of two input signals (Ua; Ub) may be formed over at least one predefined period by means of a first subtracter (12), at least one maximum value of the at least one differential signal may be detected by means of a first peak detector (16) and at least one minimum value of the at least one differential signal may be detected by means of a second peak detector (18) and at least one further differential signal (UOut) may be formed from the at least one maximum value and the at least one minimum value by means of a second subtracter (14).

Abstract: This exhaust gas scrubber for an epitaxial wafer manufacturing device includes: a scrubber inlet tube for introducing an exhaust gas discharged from an epitaxial wafer manufacturing device; and a wash tube unit formed inside the scrubber inlet tube for spraying wash water toward an interior of the scrubber inlet tube from one end thereof so as to wash adhesions inside the scrubber inlet tube, wherein the wash tube unit includes an outer tube through which inert gas constantly flows, a middle tube which is formed inside the outer tube and through which inert gas intermittently flows, and an inner tube which is formed inside the middle tube and through which the wash water and inert gas alternately flow.

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: An inlet air chilling and filtration system for a turbine. The inlet air chilling and filtration system may include a first stage spray array with a first number of spray nozzle pairs, a second stage spray array with a second number of spray nozzles pairs, and a drift eliminator.

Abstract: A method of separating water from air is provided comprising the steps of (a) contacting air having water vapor with an hygroscopic liquid mixture to produce a water rich hygroscopic liquid mixture, (b) heating at least a portion of the water rich hygroscopic liquid mixture to produce a gaseous mixture including water vapor and at least one other gaseous component, (c) condensing at least a portion of the water vapor in the gaseous mixture to produce liquid water and a depleted gaseous mixture at a first pressure, and (d) removing at least a portion of the at least one other gaseous component to maintain the first pressure below a predetermined pressure, wherein the depleted gaseous mixture is in fluid communication with the water rich hygroscopic liquid mixture. An absorber vessel is also provided for effecting the method of separating water from air.

Abstract: In a wet-process gas treatment method of treating an acid gas by using at least two treating columns connected in series, a ratio of the concentration of an acid gas at an outlet to a concentration of the acid gas at an inlet of a first treating column is set higher than a ratio of the concentration of the acid gas at an outlet to the concentration of acid gas at an inlet of at least one of the other treating columns, thereby preventing deposits from forming in the interior of connecting pipes between the columns and in the interiors of the treating columns, to prevent the connecting pipes from being blocked.

Abstract: An air purification system for treating pollutants in a gas stream. The air purification system includes a housing with a plurality of nozzles, an acidic water supply device and an alkaline water supply device. The housing introduces the gas stream. The acidic water supply device supplies acidic water for first nozzles to spray acidic mist. The alkaline water supply device supplies alkaline water for second nozzles to spray alkaline mist. The acidic mist and alkaline mist neutralize acidic gas and alkaline gas contained in the gas stream.

Abstract: A low-energy venturi pre-scrubber optimized for removing abrasive particles from a gaseous effluent is disclosed. While venturi scrubbers are efficiently used for at removing entrained particulates in air pollution control systems, they can be damaged due to the abrasive characteristics of entrained particles, such as silica particles greater than a micrometer in diameter. According to the present invention, high scrubbing efficiencies can be obtained in equipment that is not damaged by the abrasive particles by first removing the abrasive particles in a low-energy venturi, and then removing the remaining particles in a second scrubber. In addition to improving the lifetime and reducing the maintenance costs of the venturi, scrubbing fluids have fewer large particles, allowing their use in downstream components, such as evaporative coolers.

Abstract: A process for the recovery of metal oxides from a solution containing metallic salts by spray roasting of these solutions. The process is particularly suitable for spray roasting spent pickling acids. The process feeds the solution to a reactor for spray roasting of the droplets in at least two stages, where at least one evaporation stage follows at least one conversion stage to convert the metal salts to metal oxides. The device for implementing the process includes a spray roasting reactor having a first heating zone to evaporate the water and a second heating zone to convert the metal salts to oxides.

Abstract: A stepped, perforated tray is provided for increasing the available gas-slurry contact area in a flue gas desulfurization chamber. The tray redirects the horizontal flow upwardly through the tray for increased surface area and contact time with slurry for removing SOx or other contaminants from a fossil fuel combustion flue gas before releasing the flue gas to the atmosphere. The tray is adaptable for use in vertical tower systems as well.

Abstract: An air purification system which is well-suited to removing particles from outside air as the air flows into a cleanroom used in the fabrication of semiconductor integrated circuits. A housing provides at least one spray nozzle for spraying fine mist water droplets. In use, the water droplets capture the airborne particles in the air flowing through the housing and adhere to the water droplet target. The water droplets coalesce and form larger droplets which adhere to the surface of the water droplet target and ultimately collect in a drain pan. The low-density water droplet target prevents large pressure differentials from forming in the housing, which pressure differentials may otherwise cause re-vaporization of the water droplets from the target and re-flow of the particles in the flowing air.

Abstract: A scrubber for removing particles from waste gas. The scrubber comprises a chamber and a water-injecting device. The chamber has an outlet, an inlet connected to a gas inlet pipe, and a plurality of sprayers connected to a water source to spray water into the chamber. The water-injecting device is disposed at the outlet and connected to the water inlet pipe. The water-injecting device has an annular gap to inject water and provide a water film over the outlet of the chamber, filtering out particles and corrosive gases.

Abstract: In a wet-process gas treatment method of treating an acid gas by using at least two treating columns connected in series, a ratio of the concentration of an acid gas at an outlet to a concentration of the acid gas at an inlet of a first treating column is set higher than a ratio of the concentration of the acid gas at an outlet to the concentration of acid gas at an inlet of at least one of the other treating columns, thereby preventing deposits from forming in the interior of connecting pipes between the columns and in the interiors of the treating columns, to prevent the connecting pipes from being blocked.

Abstract: A scrubber for removing particles from waste gas. The scrubber comprises a chamber and a water-injecting device. The chamber has an outlet, an inlet connected to a gas inlet pipe, and a plurality of sprayers connected to a water source to spray water into the chamber. The water-injecting device is disposed at the outlet and connected to the water inlet pipe. The water-injecting device has an annular gap to inject water and provide a water film over the outlet of the chamber, filtering out particles and corrosive gases.

Abstract: A system for abating undesired component(s) from a gas stream containing same, such as halocompounds, acid gases, silanes, ammonia, etc., by scrubbing of the effluent gas stream with an aqueous scrubbing medium. Halocompounds, such as fluorine, fluorides, perfluorocarbons, and chlorofluorocarbons, may be scrubbed in the presence of a reducing agent, e.g., sodium thiosulfate, ammonium hydroxide, or potassium iodide. In one embodiment, the scrubbing system includes a first acid gas scrubbing unit operated in cocurrent gas/liquid flow, and a second “polishing” unit operated in countercurrent gas/liquid flow, to achieve high removal efficiency with low consumption of water. The scrubbing system may utilize removable insert beds of packing material, packaged in a foraminous containment structure. The abatement system of the invention has particular utility in the treatment of semiconductor manufacturing process effluents.

Abstract: A method of reducing the pressure drop in a downflow/upflow wet flue gas desulfurization (WFGD) system and of improving overall sulfur dioxide collection efficiency by converting the downflow/upflow WFGD system to an upflow single-loop WFGD system. The method includes the replacing of the downflow quencher and related duct work with a bypass for connecting the incoming flue gas duct with the upflow absorber, and the adding of a quenching zone in the absorber comprised of spray headers.

Abstract: The present invention provides improved systems and methods for scrubbing gas with a venturi scrubber. A dual spray venturi scrubber, in which a scrubbing liquid is injected upstream and counter to the flow through the venturi, provides for improved scrubbing performance, including efficient and economical scrubbing of fine particles. Specifically, the present invention reduces the scrubbing liquid pumping requirements, improves the scrubber performance, and provides better control of the pressure drop across the venturi scrubber. The control of pressure drop across the venturi can be obtained with no internal mechanisms or upstream spray.