A system for treating ethylene oxide-containing sterilization exhaust gas comprises a reaction column further comprising a column body, and an inner cavity configured to contain a liquid substrate for catalyzing ethylene oxide in ethylene oxide-containing sterilization exhaust gas; wherein the column body comprises a bottom portion having a gas inlet pipe and a liquid outlet pipe, the gas inlet pipe configured to inject the ethylene oxide-containing sterilization exhaust gas into the inner cavity and the liquid outlet pipe configured to discharge the liquid substrate from the inner cavity; and wherein, the column body comprises a top portion comprising a gas outlet pipe having a gas inlet above a liquid level of the liquid substrate; and at least one gas distributor configured to disperse the ethylene oxide-containing sterilization exhaust gas injected from the gas inlet pipe into the inner cavity.

A method, scrubbing solution and apparatus for removing a H.sub.2S scavenger, for example dithiazine, from a gas stream uses an acidic solution to convert the H.sub.2S scavenger to a salt. The acidic solution may be a phosphoric acid solution.

The disclosure provides seven integrated methods for the chemical sequestration of carbon dioxide (CO.sub.2), nitric oxide (NO), nitrogen dioxide (NO.sub.2) (collectively NO.sub.x, where x=1, 2) and sulfur dioxide (SO.sub.2) using closed loop technology. The methods recycle process reagents and mass balance consumable reagents that can be made using electrochemical separation of sodium chloride (NaCl) or potassium chloride (KCl). The technology applies to marine and terrestrial exhaust gas sources for CO.sub.2, NOx and SO.sub.2. The integrated technology combines compatible and green processes that capture and/or convert CO.sub.2, NOx and SO.sub.2 into compounds that enhance the environment, many with commercial value.

Ammonia removal equipment including a first ammonia removal apparatus that removes ammonia in a mixed gas containing hydrogen and ammonia, a second ammonia removal apparatus that is installed at a stage subsequent to the first ammonia removal apparatus and that treats a first treated gas treated by the first ammonia removal apparatus, and a first ammonia concentration measurement apparatus that measures the ammonia concentration in the first treated gas treated by the first ammonia removal apparatus.

A method, scrubbing solution and apparatus for removing a H.sub.2S scavenger, for example dithiazine, from a gas stream uses an acidic solution to convert the H.sub.2S scavenger to a salt. The acidic solution may be a phosphoric acid solution.

Disclosed are methods and systems for removing submicron particles from a gas stream, in particular from urea prilling off-gas, wherein a Venturi ejector is used. A method comprises contacting a gas stream containing submicron particles in a Venturi ejector with an injected high velocity scrubbing liquid to provide a pumping action, wherein the scrubbing liquid has an initial velocity of at least 25 m/s and wherein the ratio of scrubbing liquid and gas flow is between 0.0005 and 0.0015 (m.sup.3/h)/(m.sup.3/h).

Disclosed are methods and systems for removing submicron particles from a gas stream, in particular from urea prilling off-gas, wherein a Venturi ejector is used. A method comprises contacting a gas stream containing submicron particles in a Venturi ejector with an injected high velocity scrubbing liquid to provide a pumping action, wherein the scrubbing liquid has an initial velocity of at least 25 m/s and wherein the ratio of scrubbing liquid and gas flow is between 0.0005 and 0.0015 (m.sup.3/h)/(m.sup.3/h).

A process for purification of waste from zootechnical sources or from small agri-food companies is provided. A plant for carrying out the wastewater treatment process is also provided.

An odor filter, preferably utilized on vents of human waste containers, provides a multi-stage construction having a variety of media calculated to remove specific gasses with acid and base impregnated filter media as well as potentially regular activated charcoal. The filter construction can be provided with a multi-diameter connection capability, at least one replacement indicator and/or a safety release to assist in at least one of under-pressure and/or overpressure situations.

A process for cooling quench effluent includes providing a quench column effluent to a quench column aftercooler condensate; cooling the quench column effluent to provide a quench column aftercooler condensate; and recirculating at least a portion of the quench column aftercooler condensate to the quench column aftercooler at a rate to prevent fouling of the quench column aftercooler.