A gas conversion apparatus (100) for converting a process gas to one or more other gases comprises: means (105) for introducing process gas into a liquid medium in a column (125); and an ultrasonic energy generator (140) arranged to generate ultrasonic energy, the apparatus (100) being configured to launch ultrasonic energy generated by the generator (140) into the liquid medium such that process gas is exposed to ultrasonic energy, the apparatus (100) being arranged to allow collection of process gas that has been exposed to ultrasonic energy. The apparatus (100) also preferably comprises a microbubble generator (120) to generate microbubbles of the process gas for exposure to the ultrasonic energy. The ultrasonic energy generator (140) may be configured to generate ultrasonic energy as a consequence of a flow of a drive gas therethrough.

An exhaust gas control apparatus includes a dust collection device, an oxidation treatment device, and an ECU. The dust collection device applies a DC voltage between a charging electrode and a counter electrode, and collects particulate matter on an oxidation substrate. The ECU estimates a distribution of a deposition amount of the particulate matter deposited on the oxidation substrate in a flow direction of exhaust gas, based on input information including at least a flow rate of exhaust gas and a mass of particulate matter in exhaust gas, setting information including at least an electric field intensity between the charging electrode and the counter electrode, and history information on the oxidation treatment. The ECU carries out the oxidation treatment when the deposition amount of at least a part of the deposited particulate matter exceeds a threshold.

An exhaust gas control apparatus includes a dust collection device, an oxidation treatment device, and an ECU. The dust collection device applies a DC voltage between a charging electrode and a counter electrode, and collects particulate matter on an oxidation substrate. The ECU estimates a distribution of a deposition amount of the particulate matter deposited on the oxidation substrate in a flow direction of exhaust gas, based on input information including at least a flow rate of exhaust gas and a mass of particulate matter in exhaust gas, setting information including at least an electric field intensity between the charging electrode and the counter electrode, and history information on the oxidation treatment. The ECU carries out the oxidation treatment when the deposition amount of at least a part of the deposited particulate matter exceeds a threshold.

Systems and methods directed at removing HCN from an FCC process flue gas (and/or generated in the catalyst system reactions themselves) such that the final HCN output is satisfactory; while, in so doing, avoiding undesirable levels of other pollutants contained in that exhaust gas such as NOx. A system includes an assembly having a fluid catalytic cracking (FCC) unit generating a flue gas with HCN and NOx and a catalyst device placed in the flue gas line to remove HCN and NOx. The catalyst device having one or more SCR catalytic articles, as in one free of platinum group metal material (PGM) or a dual functioning SCR catalyst with PGM, or a combination of each. The assembly can be provided with an ammonia supplier and optionally an H2O supplier with associated injection for supply into the flue gas upstream of a catalytic article(s).

A system for treating exhaust gas of a vessel having at least one engine equipped with a turbocharger includes a storage tank configured to store a powder for treating the exhaust gas, and a dosing assembly fluidly coupled to the storage tank. The dosing assembly is configured to inject the powder into the exhaust gas at or adjacent the turbocharger, and includes a nozzle for injecting the powder into the exhaust gas. The nozzle includes a conduit configured to transport the powder, and a conical member mounted to a distal end of the conduit and defining a central hole in fluid communication with the conduit for guiding a first portion of the powder through the central hole. The distal end of the conduit and the conical member together define an annular gap configured to guide a second portion of the powder through the annular gap.

A system for treating exhaust gas of a vessel having at least one engine equipped with a turbocharger includes a storage tank configured to store a powder for treating the exhaust gas, and a dosing assembly fluidly coupled to the storage tank. The dosing assembly is configured to inject the powder into the exhaust gas at or adjacent the turbocharger, and includes a nozzle for injecting the powder into the exhaust gas. The nozzle includes a conduit configured to transport the powder, and a conical member mounted to a distal end of the conduit and defining a central hole in fluid communication with the conduit for guiding a first portion of the powder through the central hole. The distal end of the conduit and the conical member together define an annular gap configured to guide a second portion of the powder through the annular gap.