Abstract: Devices, systems, facilities, and methods for bio fermentation-based facilities, such as corn milling, ethanol, breweries, and biogas, are disclosed herein. The CO2 rich streams from the fermentation unit and the process heaters/boilers are sent to a sequestration site or pipeline via a capture unit and sequestration compressor, thereby reducing the overall emissions from the facility.

Abstract: The invention provides a humidifier with an ultrasonic suspension atomizing head, comprising a water tank, an atomization guiding tube, an atomizing head, and a cover body; the atomization guiding tube is arranged in the water tank, and the side wall of the atomization guiding tube is provided with an opening; the atomizing head is arranged in the atomization guiding tube; the cover body is arranged on the water tank and connected to the atomization guiding tube; an atomization outlet of the cover body is communicated with the atomization guiding tube. The invention has a simple structure; by arranging an atomization guiding tube and an atomizing head, the atomized water vapor does not need to roll from the bottom of the humidifier to the water surface, which achieves a good spray effect, and at the same time, eliminates the sound when the water vapor rolls.

Abstract: A carrier head for a polishing system includes a housing, a flexible membrane, a first plurality of pressure supply lines, a second plurality of pressure supply lines, and a valve assembly. The flexible membrane defines a multiplicity of independently pressurizable chambers. The valve assembly has a multiplicity of valves with each respective valve of the multiplicity of valves coupled to a respective pressure chamber from the multiplicity of independently pressurizable chambers. Each respective valve is configured to selectively couple the respective pressure chamber to one pressure supply line from a pair of pressure supply lines that include a pressure supply line from the first plurality of pressure supply lines and a pressure supply line from the second plurality of pressure supply lines.

Abstract: An improvement in a wet scrubbing process for treating gaseous industrial process streams which contain one or more of SO2, SO3, H2SO4 which comprises contacting the stream of gas with a countercurrent flow of liquid derived from a circulating liquid stream which includes (i) a purge stream configured to remove a portion of the circulating liquid having a concentration of H2SO4 from the process, and (ii) a liquid make-up stream configured to replace the portion of the circulating liquid that is removed from the circulating liquid stream, the improvement comprising controlling the flow of liquid make-up whereby the concentration of H2SO4 in the purge stream is increased to a useful value; and filtering the purge stream to remove unwanted contaminants to yield a clarified purge stream.

Abstract: Methods, systems, and devices for liquid hydrocarbon fuel production, hydrocarbon chemical production, and aerosol capture are provided. For example, a carbon-oxygen-hydrogen (C—O—H) compound may be heated to a temperature of at least 800 degrees Celsius such that the C—O—H compound reacts through a non-oxidation reaction to generate at least a hydrocarbon compound that may be at least a component of a liquid hydrocarbon fuel or a hydrocarbon chemical. The liquid hydrocarbon fuel may be a liquid when at a temperature of 20 degrees Celsius. The C—O—H compound may include biomass. In some cases, the hydrocarbon compound produced through the non-oxidation reaction includes a hydrocarbon aerosol form as the hydrocarbon compound at least as it is produced or cools. Some embodiments include aerosol capture methods, systems, and devices, which may include passing a hydrocarbon aerosol form through a material in a liquid phase in order to gather the aerosol material.

Abstract: Methods for aerosol capture are provided. In some embodiments, the method of aerosol capture may include passing an aerosol through a material in a bulk liquid phase to gather at least a portion of one or more components of the aerosol. The gathered portion of the one or more aerosol components may include at least a hydrocarbon compound. In some embodiments, the gathered portion of the one or more aerosol components includes at least a component of a liquid hydrocarbon. In some embodiments, the material in the bulk liquid phase may include a liquid hydrocarbon, which may include a hydrocarbon fuel.

Abstract: An apparatus and method for flow management and CO2-recovery from a CO2 containing hydrocarbon flow stream, such as a post CO2-stimulation flowback stream. The apparatus including a flow control zone, a gas separation zone, a pretreatment zone, and a CO2-capture zone. The CO2-capture zone is in fluid communication with the pretreatment zone to provide CO2-capture from a pretreated flowback gas stream and output a captured CO2-flow stream. The CO2-capture zone includes a flow splitter to direct a first portion of the pretreated flowback gas stream to a CO2-enricher to provide an enriched CO2-stream for mixing with a second portion of the pretreated flowback gas to form a mixed stream. The CO2-capture zone further includes at least one condenser to output the captured CO2-flow stream.

Abstract: This disclosure teaches a composition and process which makes it possible to remove floating particulates or prevent the dissemination or particulates, by the misting of a solution that readily captures any particulate material in the air. More specifically, the present disclosure teaches the composition and use of aromatic compounds that are semi-volatile organic compounds (SVOCs) or slow evaporators in water-based carriers with surfactants as the misting/fogging agent for dust suppression. The particulate material is lowered to surfaces and removed by vacuuming, damp-wiping or using a dry cloth with a cationic charge (static cloth). This method can be achieved with neutral air pressure differentials in the work areas.

Abstract: The present invention discloses a method and a device for recovering ethylene during the process for producing vinyl acetate, wherein a double solvent absorption method composed of an absorbent solution and deionized water is adopted.

Abstract: A spray dryer disperser 24, 26, 28, 30 is described for use in a spray dryer absorption (SDA) system 18 for flue gas FG impurity reduction. As such, the spray dryer disperser 24, 26, 28, 30 disperses absorbent liquid or reagent slurry droplets into contact with a hot flue gas FG stream containing gaseous impurities to produce a flue gas FG stream of reduced impurity content and dry powder end products EP. The spray dryer disperser 24, 26, 28, 30 is useful in larger capacity SDA vessels 22 of approximately 12 to 22 meters in diameter or larger, to avoid disperser 24, 26, 28, 30 shroud 34a scale deposits, to avoid reagent slurry spray cloud suppression, to avoid vessel 22 wall 22b scale deposits and to achieve increased droplet rotational momentum for increased droplet flue gas FG penetration for efficient impurity reduction.

Abstract: This disclosure teaches a composition and process which makes it possible to remove floating particulates or prevent the dissemination or particulates, by the misting of a solution that readily captures any particulate material in the air. More specifically, the present disclosure teaches the composition and use of aromatic compounds that are semi-volatile organic compounds (SVOCs) or slow evaporators in water-based carriers with surfactants as the misting/fogging agent for dust suppression. The particulate material is lowered to surfaces and removed by vacuuming, damp-wiping or using a dry cloth with a cationic charge (static cloth). This method can be achieved with neutral air pressure differentials in the work areas.

Abstract: A lean solvent is produced from a CO2 rich solvent using heat exchange with a conditioned stream in a reboiler. A power generator generates a low pressure steam from high pressure steam. A portion of the low pressure steam is sent to a fluid conditioning unit, which conditions the low pressure steam to a temperature and pressure required to allow for the production of lean solvent from a rich solvent in a reboiler.

Abstract: Systems and methods for removing hydrogen sulfide from biogas resulting from anaerobic digestion of biodegradable waste utilize scrubbing vessels with pressure release devices to vent biogas when necessary to avoid over pressurization of the digesters. Use of iron containing sulfide scavengers in the digesters is avoided which avoids the disposal costs associated with iron containing sludge and the regular need to shut down the digesters to remove scale.

Abstract: A dust suppression apparatus comprising: (a) a turntable; (b) an engine; (c) a water mist blower comprising an air conduit, a plurality of water nozzles positioned so as to supply a spray of water to the air conduit, and a fan positioned so as to supply a stream of air through the air conduit, the water mist blower and the engine mounted on the turntable, the turntable adapted to permit the air conduit to be rotated horizontally, and the air conduit mounted so as to permit the air conduit to tilt vertically; (d) a water conduit adapted to supply pressurized water to the plurality of water nozzles; (e) a belt drive connected to the engine and adapted to supply power to the fan, and (f) a constant velocity joint connecting the belt drive to the fan.

Abstract: To develop a means for effectively utilize terpene compounds contained in tree leaves, whereby branches and leaves cut in tree thinning and pruning can be effectively utilized as a resource. For this purpose, provided are a monoterpene component-rich essential oil containing 90% or more of monoterpene components; a method for producing the monoterpene component-rich essential oil which includes subjecting coniferous leaves to microwave steam distillation and collecting a distillate thus obtained; and a method for removing environmental pollutants which includes bringing the monoterpene component-rich essential oil into contact with atmosphere containing the environmental pollutants.

Abstract: The disclosed embodiments provide systems for the removal and use of tar from a biomass gasification system. For example, in one embodiment, a biomass gasification system includes a reactor configured to gasify a biomass fuel in the presence of air to generate a producer gas. The system also includes an absorber configured to receive a mixture of the producer gas and tar and to absorb the tar into an organic solvent to produce treated producer gas and a rich solvent mixture containing at least a portion of the tar. The system further includes a recycle line configured to direct the rich solvent mixture to a biomass gasifier.

Abstract: A humidifier for treating humidified air with germicidal light is provided. The humidifier includes a water reservoir, an atomizer to atomize a supply of water, and an ultraviolet light source to expose the atomized water to germicidal light. The ultraviolet light source extends vertically within a cylindrical channel to irradiate the atomized water dissipating upwardly from the atomizer. The water reservoir can include a carbon filter and a hardness-removing module for removing containments and metal oxides from the water supply. A control panel indicates the remaining useful life of the ultraviolet light source, the carbon filter and the hardness-removing module based on historical humidifier usage and water quality levels.

Abstract: The CO2 capture system by chemical absorption for removing CO2 from a combustion exhaust gas by a solvent, comprising: an absorber for absorbing CO2 by a solvent, a regenerator for heating a rich solvent absorbed CO2 thereby releasing CO2, a gas exhaust system for discharging gas from the regenerator, a gas compressor installed in the gas exhaust system, a heat exchanger disposed downstream of the gas compressor for exchanging heat between compressed gas and rich solvent to be supplied to the regenerator, a gas-liquid separator disposed downstream of the heat exchanger for separating gas from condensed water, a condensed water supply system for supplying condensed water from the gas-liquid separator to the regenerator, another gas exhaust system for discharging gas containing high-concentration CO2 from the gas-liquid separator, and a compressor disposed downstream of the gas-liquid separator in the another gas exhaust system for pressurizing the gas containing high-concentration CO2.

Abstract: Horizontal duct scrubbing systems for removing particulate matter from a gas are disclosed. The horizontal scrubbing systems may receive a particulate-containing gas stream (e.g., containing PM10 and/or PM2.5 particulate matter), and remove at least some of such particulates by spraying liquid droplets co-current to the flow of the gas stream, where the liquid droplets have a volume median droplet diameter (DV0.5) of from 240 microns to 600 microns. The scrubbing system may be substantially free of flow deflection members between a liquid inlet manifold and a demister. The system may be remove at least 50 wt. % PM10 and/or PM2.5 particulate matter from the gas stream.

Abstract: The CO2 capture system by chemical absorption for removing CO2 from a combustion exhaust gas by a solvent, comprising: an absorber for absorbing CO2 by a solvent, a regenerator for heating a rich solvent absorbed CO2 thereby releasing CO2, a gas exhaust system for discharging gas from the regenerator, a gas compressor installed in the gas exhaust system, a heat exchanger disposed downstream of the gas compressor for exchanging heat between compressed gas and rich solvent to be supplied to the regenerator, a gas-liquid separator disposed downstream of the heat exchanger for separating gas from condensed water, a condensed water supply system for supplying condensed water from the gas-liquid separator to the regenerator, another gas exhaust system for discharging gas containing high-concentration CO2 from the gas-liquid separator, and a compressor disposed downstream of the gas-liquid separator in the another gas exhaust system for pressurizing the gas containing high-concentration CO2.

Abstract: Post-combustion conditioning systems are described that include a flue gas conditioning device configured to condition an exhaust stream to produce a conditioned stream. First and second outlet ducts can be fluidly coupled to, and substantially supported by, the flue gas conditioning device. This advantageously can eliminate costly ductwork, reduce the space required, and reduce the pressure drop of the system. The first outlet duct can fluidly couple the flue gas conditioning device to an exhaust duct, such that the conditioned stream can flow from the first conditioning device via the first outlet duct.

Abstract: Systems and methods for gas processing are described that utilize two or more cells that are fluidly coupled to one another by a common liquid space. Via the common liquid space, each of the cells can be coupled to a fluid outlet. The cells can each include an absorber and/or other gas processing equipment. A feed gas can be separately fed to each of the cells for processing. The cells can be independently operable, such that not all of the cells must be operated simultaneously.

Abstract: A process for quickly removing hydrocarbon contaminants and noxious gases in a safe and effective manner from catalytic reactors, other media packed process vessels and associated equipment in the vapor phase without using steam. The cleaning agent contains one or more solvents, such as terpenes or other organic solvents. The cleaning agent is injected into contaminated equipment, along with a carrier gas, in the form of a cleaning vapor.

Abstract: A method and system for transporting and processing sour gas are provided. The method includes collecting a sour gas at a collection location, which has an associated sweetening device, and delivering a solvent to the sweetening device from a regeneration device remote therefrom. The sour gas is treated at the collection location with the solvent in the associated sweetening device to form a sweetened gas and a sour gas-rich solvent. The sweetened gas is transported from the sweetening device to a gas processing plant remote therefrom, and the sour gas-rich solvent from the sweetening device is delivered to the regeneration device for regeneration therein.

Abstract: The present invention relates to methods and systems for improving the utilization of energy in a cement manufacturing plant comprising an absorption based contaminant, e.g. CO2, capture process using thermal regeneration of a liquid absorbent. The methods and systems of the present invention are characterized in that the thermal regeneration of the liquid absorbent is at least partially effected using a hot exhaust gas stream generated in the kiln of the cement manufacturing plant.

Abstract: The method for eliminating acidic compounds contained in a gaseous effluent consists of placing into contact, in column C1, a gaseous effluent 1 with an absorbent solution 4 comprising an aqueous solution of one or a plurality of dihydroxyalkylamines having one of the formulas (I) and (II).

Abstract: The present invention provides a permanent and cost-effective composite electrode for electrolytically producing alkaline water, comprising an electrode core made of steel, a filler densely packed around the electrode core, said filler capable of creating a mildly aqueous and alkaline environment to motivate formation of a layer of magnetite over a surface of the electrode core, and a housing enclosing the filler, said housing having a pore size selected such that very low permeation of gas and liquid takes place. The invention also provides an apparatus comprising the composite electrode, and the use of the alkaline water produced by the apparatus of the invention. According to the invention, no additional undesired side products, such as toxic chlorine gas and other pollutants, are produced and discharged to the environment.

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 process for separating off solid particles, in particular coke particles, from a water phase by means of gravity in a plant for generating hydrocarbons by cracking a hydrocarbonaceous feed, and also to a device for carrying out the process. In contrast to the prior art, the water phase is taken off predominantly from a point above the column bottom B via the outlet A. The first gravity separator 2 which is constructed as a multistage settling tank 2 is situated not beneath, but next to, the scrubbing water column 1. The bottom phase of the scrubbing water column 1 already acts as a part of the first gravity separator 2. Thus, via the outlet 5 in the column bottom B, a heavy water phase which is loaded with coke particles is already taken off and passed into the second gravity separator 3. This heavy water phase is further treated, together with the heavy water phase which is loaded with coke particles from the recesses 6 of the multistage settling tank 2.

Abstract: The invention relates to a method and device for influencing the smell coming from shaft openings of underground sewers, in which water droplets are sprayed into the air in shafts (1) of underground sewers which are open in the direction of the ambient air. Said spraying device comprises a pressure vessel (3) containing water and a nozzle (4) having one or more fine openings through which water can escape from the pressure vessel (3), the pressure vessel (3) being subject to a hydrostatic pressure which is by at least 2 bars greater than the ambient pressure, and the diameter of one or more nozzle openings being less than 130 ?m.

Abstract: Organic sulfur compounds contained in refinery off gas streams having either high ort low concentrations of olefins are converted to hydrogen sulfides which can be then be removed using conventional amine treating systems. The process uses a catalytic reactor with or without a hydrotreater depending on the olefin concentration of the off gas stream. The catalytic reactor operates in a hydrogenation mode or an oxidation mode to convert a majority of organic sulfur compounds into hydrogen sulfides.

Abstract: The present invention relates to a method of removing an absorbate from gases or gas mixtures containing absorbate, in which the gas or gas mixture is contacted by a liquid mixture of absorption agent and absorbate or of liquid absorbate-free absorption agent, wherein the absorbate is absorbed at least partially by the liquid mixture of absorption agent and absorbate and is concentrated therein or is absorbed by the liquid absorbate-free absorption agent while forming a liquid mixture of absorption agent and absorbate. It is characteristic in the method in accordance with the present invention that the absorption agent used and the absorbate used have a miscibility gap.

Abstract: This technology relates to the enlargement by water condensation in a laminar flow of airborne particles with diameters of the order of a few nanometers to hundreds of nanometers to form droplets with diameters of the order of several micrometers. The technology presents several advanced designs, including the use of double-stage condensers. It has application to measuring the number concentration of particles suspended in air or other gas, to collecting these particles, or to focusing these particles.

Abstract: A trap Including: an inlet configured to receive a fluid conveying nanostructures; ionic liquid configured to trap the nanostructures; and an outlet for the fluid.

Abstract: An air cleaner is described comprising a housing having an air inlet and an air exhaust extending therethrough, a refill for containing a reservoir of liquid which is releasable from the housing, a nebulizer within the housing configured, in use, to be in fluid contact with the source of liquid to generate a mist of liquid droplets, said nebulizer being configured, in use, to eject the mist upwardly, a chamber within the housing in which the mist is retained, a fan within the housing configured, in use, to generate a flow of air through the air inlet and into the chamber such that at least some of the contaminants in the air flow are urged by the mist out of the flow of air and toward the refill. A refill for the air cleaner is also described as well as the use of said air cleaner.

Abstract: A dust suppression apparatus comprising: (a) a turntable; (b) an engine; (c) a water mist blower comprising an air conduit, a plurality of water nozzles positioned so as to supply a spray of water to the air conduit, and a fan positioned so as to supply a stream of air through the air conduit, the water mist blower and the engine mounted on the turntable, the turntable adapted to permit the air conduit to be rotated horizontally, and the air conduit mounted so as to permit the air conduit to tilt vertically; (d) a water conduit adapted to supply pressurized water to the plurality of water nozzles; (e) a belt drive connected to the engine and adapted to supply power to the fan, and (f) a constant velocity joint connecting the belt drive to the fan.

Abstract: A construction element for a plant for capture of an acidic gas using an aqueous amine absorbent, wherein at least a part of a surface of said element comprises a polyolefin, and a hydrolytically stable antioxidant, is described. Additionally, a liner comprising said polyolefin and the hydrolytically stable antioxidant, is described. The construction element may be a column, a pipe, an insert, like a column packing element or a tray. An apparatus for capturing CO2 using the construction elements, is also described.

Abstract: Provided is a method, liquid distributor and reactor for contacting a gas with a liquid in a rotating packed bed. The method comprises providing a rotating packed bed comprising two sets of rotatable packing rings disposed within a chamber and defining an interior region. The rotating packed bed also comprises at least one liquid distributor with an inlet for accepting a liquid, the inlet in communication with an exit port for infusing the liquid into the interior region. The liquid distributor also comprises at least one gas outlet for accepting gas which has passed through the packed bed and for removing the gas from the interior region. The two sets of rotatable packing rings are caused to rotate. Liquid is infused into the interior region by way of the liquid inlet, and gas is injected through at least one gas inlet into the interior region, with the liquid and gas passing through each of the packing rings in countercurrent flow.

Abstract: Methods and apparatus relate to recovery of carbon dioxide and/or hydrogen sulfide from a gas mixture. Separating of the carbon dioxide, for example, from the gas mixture utilizes a liquid sorbent for the carbon dioxide. The liquid sorbent contacts the gas mixture for transfer of the carbon dioxide from the gas mixture to the liquid sorbent. Contacting of the sorbent with the gas mixture and/or desorption of the carbon dioxide from the liquid sorbent utilize hollow-fiber contactors that have permeable walls and incorporate particles distinct from a remainder of the walls to influence wetting properties of the contactors.

Abstract: Imido-acid salts and compositions containing imido-acid salts are described herein. Methods of their preparation and use are also described herein. The methods of using the imido-acid salts include the reduction of volatile compounds from gas and liquid streams and the delivery of pharmaceutical agents to subjects.

Abstract: A system and method is provided for removing a condensate from a synthetic gas treatment system. The method includes feeding a first fluid stream into a bottom section of a scrubber chamber defined by a scrubber shell of a scrubber. The first fluid stream includes at least one condensable component. A second fluid stream is fed into a top section of the scrubber chamber, such that the second fluid stream flows in the scrubber chamber in a countercurrent flow direction to the first fluid stream. The second fluid stream contacts the first fluid stream causing the at least one condensable component to form the condensate, such that the condensate and the second fluid stream are collected in the bottom section of the scrubber chamber. The method further includes feeding a third fluid stream into the top section of the scrubbing chamber, such that the third fluid stream contacts the condensate and the second fluid stream and forms an emulsion.

Abstract: The gaseous effluent is contacted with an aqueous solution comprising at least one amine and at least one amine degradation inhibiting compound. A stainless steel withstanding corrosion upon contact with the amine degradation inhibiting compound is first selected. Equipments whose surfaces in contact with the aqueous solution are made from this stainless steel are used.

Abstract: Presented is a method and apparatus for treating an exhaust gas. A series of filters and conditioning units are used to separate and extract various substances from the exhaust gas, typically originating from an industrial process. In an exemplary embodiment, a cyclone filter, a ceramic filter, a baghouse filter, and a pair of gas conditioners are used to initially separate and extract iron-rich dust from an exhaust gas and then extract zinc from the gas.

Abstract: The invention relates to a separation system comprising a flow inlet (16). The separation system comprises a swirl valve (100), arranged to receive and control the flux of a fluid flow via the flow inlet (16) and to generate a swirling flow, swirling about a central axis (11). The separation system further comprises a separation chamber (40) positioned downstream with respect of the swirl valve (100) to receive the swirling flow from the swirl valve (100), wherein the separation chamber (40) comprises a first and second flow outlet (41, 42). The first flow outlet (41) is positioned to receive an inner portion of the swirling flow and the second outlet (42) is positioned to receive an outer portion of the swirling flow.

Abstract: A gasification system includes a water source, a downstream system configured to receive a first stream having water from the water source, and a carbon a carbon dioxide injector configured to adjust a pH of the water using a second stream having carbon dioxide to form pH-adjusted water.

Abstract: The invention relates to a fluid storage tank having an interior volume and a floor and having an internal spill containment chamber comprising a vent gas scrubbing apparatus or scrubber. The chamber may be defined by a containment wall which completely separates the chamber from the tank interior volume. The containment wall may comprise an exterior portion which extends beyond the tank wall. The scrubber is disposed within the chamber and comprises a gas inlet passing through the containment wall into the tank interior volume, a gas outlet for venting scrubbed gases, and a gas scrubbing chemical storage and circulation system.

Abstract: A method for recovering carbon dioxide (CO2) from a gas stream is disclosed. The method includes the step of reacting CO2 in the gas stream with fine droplets of a liquid absorbent, so as to form a solid material in which the CO2 is bound. The solid material is then transported to a desorption site, where it is heated, to release substantially pure CO2 gas. The CO2 gas can then be collected and used or transported in any desired way. A related apparatus for recovering carbon dioxide (CO2) from a gas stream is also described herein.

Abstract: A pickling process for descaling metal includes a two-stage filtering process to remove pickling liquor fog, mist, and/or vapors from a gas collected during the descaling process. The process includes a two-stage filtering arrangement that includes a first stage filter, which is arranged to remove a liquid phase of the pickling liquor from the gas, and a second stage filter, which is arranged to remove a gaseous phase of the pickling liquor the said gas. The recovered pickling liquor can advantageously be recycled for reuse because it is recovered in a relatively higher concentration that has heretofore been possible.

Abstract: The present invention provides a process and an apparatus for transferring a solute from a first fluid to a second fluid immiscible in each other.

Abstract: The portable air purification device provides extreme portability such that the device can be placed virtually anywhere desired. Should an area need the device, one person can easily transport as needed. Also important is the separability of the vacuum canister and filtration canister. Often it may be advantageous to place the vacuum canister strategically, and the filtration canister supplying purified air in another location. The device provides for such via the separate canisters and the transfer hose, which can be almost any length needed. The device uses liquid filtration media, solid filtration media, and a HEPA filter.