A multi-stage process for reducing the environmental contaminants in an ISO8217 compliant Feedstock Heavy Marine Fuel Oil involving a core desulfurizing process and a ultrasound treatment process as either a pre-treating step or post-treating step to the core process. The Product Heavy Marine Fuel Oil complies with ISO 8217 for residual marine fuel oils and has a sulfur level has a maximum sulfur content (ISO 14596 or ISO 8754) between the range of 0.05 mass % to 1.0 mass. A process plant for conducting the process is also disclosed.

This invention provides a continuous liquid phase type wet exhaust gas treatment method for removing sulfur oxides from exhaust gas and collecting it as gypsum, which method is simple and humidifying liquid is uniformly sprayed into exhaust gas with it. The method is characterized in that humidifying liquid is injected downwardly in a region where exhaust gas flows vertically downwardly.

An electrostatic precipitator module and a desulfurization system are capable of easily discharging wash water from a wet electrostatic precipitator module. The electrostatic precipitator module includes an arrangement of discharge electrodes and collecting electrodes alternately disposed and spaced apart from each other, the discharge electrodes configured to be charged to a predetermined voltage for generating a corona discharge between the discharge electrodes and the collecting electrodes; and tie rods for fixing the discharge electrodes and the collecting electrodes. Each collecting electrode has a lower edge inclined downward with respect to the ground. The lower edge of each collecting electrode includes separate lower edge portions respectively inclined downward from opposite side ends of the collecting electrode and a lowermost point at which wash water is concentrated and discharged to a discharge guide installed directly under the lowermost points. The discharge guide has a width substantially smaller than the collecting electrode.

According to an embodiment of the invention, a process for substantially completely removing sulfur dioxide and ammonia from a gas stream is disclosed. The process involves lowering the vapor pressure in a scrubber by contacting the gas stream with one or more streams of re-circulating chilled media. The process further involves adjusting the pH of the process solution in the scrubber to within a predetermined range. The lowering of the vapor pressure and pH adjustment results in an increase in the solubility of sulfur dioxide and ammonia in the process solution thereby facilitating a substantially complete removal of sulfur dioxide and ammonia from the gas stream.

A catalyst comprises a mixture of 95% vol. to 30% vol. of an activated carbon catalyst and from 5% vol. to 70% vol. of a filler material as well as a configuration of such a catalyst for the removal of SO.sub.2, heavy metals and/or dioxins form waste gas and liquids.

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.

A system includes a purification unit configured to process a vapor stream including sulfur dioxide. The purification unit includes an inlet configured to allow the vapor stream to enter the purification unit. The purification unit includes a steam coil configured to circulate steam and provide a source of heat. The purification unit includes a packed bed. The purification unit includes a tray configured to accumulate sulfur. The purification unit includes an absorber section configured to remove at least a portion of the sulfur dioxide from the vapor stream. The purification unit includes an outlet configured to allow an effluent with a lower sulfur dioxide content than the vapor stream to exit the purification unit. The system includes a sulfur tank including a vent line in fluid communication with the inlet. The vent line is configured to allow vapor to flow from the sulfur tank to the purification unit.

A method and installation for removing a gas from a flow of a gas mixture. A first liquid (82) is introduced in the flow (106) for evoporative cooling and saturation of the gas mixture. Small droplets of a second liquid (84) are provided which are capable of adsorbing and dissolving said gas and of a size small enough not to be sedimented by gravitation and big enough to be centrifugally separated. The small droplets are sprayed into the flow for adsorbing and dissolving said gas into the droplets, and the small droplets are centrifugally separated from the flow.

A process plant and a process for production of sulfur from a feedstock gas including from 15% to 100 vol % H.sub.2S and a stream of sulfuric acid, the process including a) providing a Claus reaction furnace feed stream with a substoichiometric amount of oxygen, b) directing to a Claus reaction furnace operating at elevated temperature, c) cooling to provide a cooled Claus converter feed gas, d) directing to contact a material catalytically active in the Claus reaction, e) withdrawing a Claus tail gas and elementary sulfur, f) directing a stream comprising said Claus tail gas to a Claus tail gas treatment, wherein sulfuric acid directed to said Claus reaction furnace is in the form of droplets with 90% of the mass of the droplets having a diameter below 500 μm, with the associated benefit of such a process efficiently converting all liquid H.sub.2SO.sub.4 to gaseous H.sub.2SO.sub.4 and further to SO.sub.2.

The methods and systems are disclosed which leverage sulfur abatement resources present at most refineries or other hydrocarbon processing plants, such as natural gas processing plants to capture and treat sulfur-containing byproducts, such as SO.sub.2, generated during the regeneration of spent HDP catalysts. Thus, the disclosed methods and systems allow for converting hazardous waste spent catalyst to a salable product at it source while simultaneously capturing the sulfur oxides removed from the catalyst and converting them to a useful product instead of a resultant waste stream requiring management and/or disposal. Thus, spent sulfur bearing refinery wastes, such as HDP catalyst, can be roasted or regenerated at the refinery site to convert the hazardous sulfur-bearing wastes into one or more salable products.