A sorbent composition for removing mercury from flue gas is provided. The sorbent composition contains at least a powdered sorbent, an oxidant and a catalyst. Methods of cleaning flue gas are also provided, which includes injecting the sorbent composition into the flue gas, wherein the powdered sorbent has a fifty percent distribution particle size of from about 25 micrometers to about 75 micrometers.

A process is disclosed for removing nitrous components from a raw liquid nitric acid stream to produce a bleached nitric acid product (55). The raw liquid nitric acid stream (37) is from an absorber (19) of a nitric acid process. The process comprises contacting the raw nitric acid liquid stream with an oxidising gas (12) in a bleaching stage (52). At least some of the gas effluent (12c) from the bleaching stage enters (12d) a combustion stage (15) of the nitric acid process. The oxidising gas (12) entering the bleaching stage (52) may comprise at least about one-third of an oxidising gas feed (12) to the nitric acid process. At least about one-tenth of the bleaching stage gas effluent (12c) may enter (12d) the combustion stage (15).

An air treatment unit may include an air inlet to receive a flow of input air for treatment and a reaction reservoir configured to hold an aqueous air treatment solution. The air treatment unit may also include an air dispersing element flow connected with the air inlet, wherein the air dispersing element is configured to convert at least a portion of the flow of input air into a plurality of microbubbles for introduction into the aqueous air treatment solution, such that an amount of one or more target gas species contained within the plurality of microbubbles is reduced through reaction with the aqueous air treatment solution. The unit may include an air outlet configured to output treated air from the reaction reservoir.

Certain exemplary embodiments can provide a system, machine, device, manufacture, and/or composition of matter adapted for and/or resulting from, and/or a method for, activities that can comprise and/or relate to contacting an aerobic contaminated gas stream with a solution comprising approximately Ferric MGDA, the aerobic contaminated gas stream comprising hydrogen sulfide.

Plasma is generated in a gas phase in a processing tub to produce a reforming component, the produced reforming component is dissolved in a liquid and is dispersed in the liquid to produce a reforming liquid, the produced reforming liquid is discharged from the processing tub to be stored in the storage tub, and gas is supplied from a gas supplier into the reforming liquid in the storage tub. The supplied gas has a bubble shape, comes into contact with the reforming liquid stored in the storage tub, and is deodorized.

Techniques for removing sulfur compounds from a sulfur-containing gas stream can include contacting the gas with an absorption solution comprising a metal cation capable of reacting with the sulfur compound to form a metal sulphide precipitate and/or a metal mercaptide precipitate. In addition, the treatment can include controlling a concentration of the precipitates below a threshold to maintain rheological properties; subjecting the precipitate-enriched solution to vitalization; subjecting the precipitate-enriched solution to regeneration including oxidation; and/or other features to enhance the sulfur removal operations.

The invention is a device and method for purifying sulfur dioxide and nitrogen oxide in flue gas with an electrolysis-chemical advanced oxidation enhanced ammonia method. The device includes a thermal activation reactor, ammonium hydroxide storage tank, absorption tower, electrolytic bath and crystallization separator. The method takes raw material part of an ammonium sulfate solution that is a reaction product of ammonia and sulfur oxide in flue gas, and an ammonium persulfate solution prepared by electrolysis of an electrolytic bath as an oxidant to enhance the efficiency of purifying sulfur dioxide and nitrogen oxide in the flue gas with an ammonia method. A thermal activation reactor activates an ammonium persulfate containing solution to generate a strong oxidizing SO4.sup., so that NO.sub.x and SO.sub.2 in the flue gas may be more efficiently converted into a product having higher solubleness for enhanced removal of sulfur dioxide and nitrogen oxide in the flue gas.

The present invention provides a joint method of cultivating microalgae combined with denitrating an industrial waste gas and a system useful for the same. The joint method comprises the steps of: (1) a step of cultivating microalgae; (2) a separation step of separating a microalgae suspension obtained from step (1) into a wet microalgae (microalgae biomass) and a residual cultivation solution; (3) a NOx absorbing/immobilizing step of denitrating an industrial waste gas with the residual cultivation solution obtained from step (2); wherein the nutrient stream absorbed with NOx obtained from step (3) is used to provide nitrogen source to the microalgae cultivation of step (1). During the microalgae cultivation, EM bacteria is added into the microalgae suspension. The microalgae is preferably Chlorella sp., Scenedesmus sp., Monoraphidium sp. or Spirulina sp.

A method for removing noxious, hazardous, toxic, mutagenic, and/or carcinogenic compounds and/or precursor compounds from a comingled gas, liquid and/or solid stream is described. In one embodiment, the method includes optionally passing the stream through an ambient temperature condenser followed by passing the stream through a spray venturi scrubber, a chilled condenser, a gas/solid separator, and a series of wet scrubbers to remove at least a portion of the compounds.

Systems and methods for increasing removal efficiency of at least one filter medium. In some embodiments, at least one oxidizing agent is introduced into the flue gas stream, so as to react SO2 with the at least one oxidizing agent to form sulfur trioxide (SO3), sulfuric acid (H2SO4), or any combination thereof. Some of the embodiments further include introducing ammonia (NH3) and or dry sorbent into the flue gas stream, so as to react at least some of the sulfur trioxide (SO3), at least some of the sulfuric acid (H2SO4), or any combination thereof, with the ammonia (NH3) and form at least one salt.