A system and method for purifying engine exhaust by using ozone; the system for purifying engine exhaust by using ozone comprises a reaction field (202), which is used to mix an ozone stream and an exhaust stream for reaction; the system has an excellent purification effect without needing to add a large amount of urea.

A system and method for purifying engine exhaust by using ozone; the system for purifying engine exhaust by using ozone comprises a reaction field (202), which is used to mix an ozone stream and an exhaust stream for reaction; the system has an excellent purification effect without needing to add a large amount of urea.

A method of controlling an apparatus that removes specified substances from a process gaseous stream can control at least one fan and a rotary wheel that removes the specified substances. The method includes measuring a pressure difference of the process gaseous stream across upstream and downstream sides of the rotary wheel, comparing the measured pressure difference to a predetermined pressure range, and controlling the at least one fan to increase or decrease its speed if the measured pressure difference is outside of the predetermined pressure range so as to change the pressure difference so as to be within the predetermined pressure range.

An apparatus, method and system remove contaminants from a vapor. In an embodiment, a contaminant removal apparatus includes a vacuum box. The vacuum box is a vessel. The apparatus also includes a demister pad disposed in the vacuum box. A vapor is introduced to the vacuum box on an opposing side of the demister pad from a vapor exit from the vacuum box.

An apparatus, method and system remove contaminants from a vapor. In an embodiment, a contaminant removal apparatus includes a vacuum box. The vacuum box is a vessel. The apparatus also includes a demister pad disposed in the vacuum box. A vapor is introduced to the vacuum box on an opposing side of the demister pad from a vapor exit from the vacuum box.

An exhaust gas purifying and heat recovering system and method for sludge treatment. The system comprises: a first heat exchange flow path including first, second, and third heat exchangers, a first heat exchange medium that is circulated in the first heat exchange flow path to heat process gas for sludge treatment in the first heat exchanger, a second purification and heat exchange flow path including a heat exchange tank containing a second liquid heat exchange medium and which receives the exhaust gas after sludge treatment, and a third dirty liquid separation flow path including a dirty liquid separation tank provided between a dirty liquid outlet of the heat exchange tank and a clean liquid inlet of the heat exchange tank for separating the dirty liquid after purging the exhaust gas, the separated liquid being again directed to the clean liquid inlet of the heat exchange tank.

An exhaust gas purifying and heat recovering system and method for sludge treatment. The system comprises: a first heat exchange flow path including first, second, and third heat exchangers, a first heat exchange medium that is circulated in the first heat exchange flow path to heat process gas for sludge treatment in the first heat exchanger, a second purification and heat exchange flow path including a heat exchange tank containing a second liquid heat exchange medium and which receives the exhaust gas after sludge treatment, and a third dirty liquid separation flow path including a dirty liquid separation tank provided between a dirty liquid outlet of the heat exchange tank and a clean liquid inlet of the heat exchange tank for separating the dirty liquid after purging the exhaust gas, the separated liquid being again directed to the clean liquid inlet of the heat exchange tank.

The challenge of the present invention is to provide a multilayer filter medium whose deodorizing performance after a long-term storage of the filter medium is suppressed from deteriorating and which is superior in deodorizing performance and exhibits low pressure drop. A multilayer filter medium includes three or more nonwoven fabric layers superposed together and has two or more interlayer regions each formed by two adjacent layers of the nonwoven fabric layers, in which a first interlayer region of the interlayer regions contains functional particles A having an average particle diameter of 50 to 100 m, and a second interlayer region selected from the interlayer regions excluding the first interlayer region contains functional particles B having an average particle diameter of 150 to 500 m.

The challenge of the present invention is to provide a multilayer filter medium whose deodorizing performance after a long-term storage of the filter medium is suppressed from deteriorating and which is superior in deodorizing performance and exhibits low pressure drop. A multilayer filter medium includes three or more nonwoven fabric layers superposed together and has two or more interlayer regions each formed by two adjacent layers of the nonwoven fabric layers, in which a first interlayer region of the interlayer regions contains functional particles A having an average particle diameter of 50 to 100 m, and a second interlayer region selected from the interlayer regions excluding the first interlayer region contains functional particles B having an average particle diameter of 150 to 500 m.

A method for oxidizing a waste stream having hydrogen therein includes flowing the waste stream with hydrogen into an oxidant stream for mixing the streams in a proportion for providing a mixture below lower flammability limits (LFL), including the LFL of hydrogen; and introducing the mixed streams into a ceramic matrix bed of a flameless thermal oxidizer maintained at a temperature above auto-ignition temperature of the mixture. A related apparatus is also provided.