A process for treating effluent streams in a renewable transportation fuel production process is described. One or more of the sour water stream and an acid gas stream are treated directly in thermal oxidation section. The process allows the elimination or size reduction of a sour water stripper unit, waste water treatment plant, and sulfur recovery unit.

A process for treating a sulfurous fluid to form gypsum and magnesium carbonate, whereby the sulfurous fluid is scrubbed with a sequestrating agent to yield a scrubbed fluid, gypsum and magnesium sulfate. The flue gas desulfurized gypsum is isolated from the magnesium sulfate solution by filtration or centrifugation. The magnesium sulfate is reacted with a carbonate salt to produce a magnesium carbonate whereby the reaction conditions are controlled to control the properties of the magnesium carbonate produced.

The device for producing and treating a gas stream (F) includes an exchange enclosure (2) having at least a first discharge opening (2b) for a gas stream, means (3; 4) for supplying the enclosure with a liquid (L), means (3; 5) for discharging the liquid (L) contained in the exchange enclosure (2) and aeraulic means (6), which make it possible, during operation, to create, by means of suction or blowing, an incoming gas stream (F) coming from outside the exchange enclosure (2), so that said incoming gas stream (F) is introduced into the volume of liquid (V) contained in the exchange enclosure (2), and an outgoing gas stream (F′), treated by direct contact with said volume of liquid, rises inside the exchange enclosure and is discharged out of the exchange enclosure (2) through the discharge opening (2b).

A carbon dioxide recovery system includes: a heat exchanger that is disposed between a boiler and a desulfurization device, configured to cool exhaust gas flowing from the boiler to the desulfurization device, and configured to heat a heat medium; and a carbon dioxide recovery device that is configured to, when supplied with heat of the heat medium, separate and recover carbon dioxide from an absorber which has absorbed the carbon dioxide.

The present invention includes a fuel injection amount sensor for detecting an injection amount of oil, a pretreatment desulfurization agent injection amount sensor for detecting an injection amount of a pretreatment desulfurization agent, and a control panel for controlling and monitoring the injection amount of the pretreatment desulfurization agent so that the predetermined desulfurization agent is mixed with the fuel in a predetermined mixing ratio. The fuel injection amount sensor is disposed on a fuel supply line between a fuel tank and a marine engine, and the pretreatment desulfurization agent injection amount sensor is disposed between a downstream fuel supply line installed downstream of the fuel injection amount sensor and a pretreatment desulfurization agent tank.

A process for hydrotreating a feed stream comprising a biorenewable feedstock is disclosed. The process comprises hydrotreating the feed stream in the presence of a hydrotreating hydrogen stream and a hydrotreating catalyst to provide a hydrotreated stream. The hydrotreated stream is separated into a hydrotreated liquid stream and a hydrotreated gas stream. The hydrotreated liquid stream is subjected to stripping to provide a stripper off-gas stream. At least a portion of the stripper off-gas stream is contacted with a caustic stream to provide a sulfur-lean gas stream and a sulfur-rich caustic stream. The sulfur-rich caustic stream is further treated to provide a treated gas stream.

A process for converting natural calcium carbonate into precipitated calcium carbonate, involving treating the natural calcium carbonate with a sulfate to produce a gypsum and reacting the gypsum with at least one carbonate source to produce precipitated calcium carbonate. The crystalline polymorph, particle size, and various other characteristics of the precipitated calcium carbonate are controlled by varying conditions during the reacting. Since the natural calcium carbonate is not calcined, the process relates to a low energy method of producing precipitated calcium carbonate of controlled polymorph and particle size with limestone, marble, or chalk as the calcium source.

Improved methods and systems are provided for the on-board removal of sulfur dioxide generated by a marine vessel. The method includes spraying an alkaline fluid into the flue gas to produce a saturated flue gas stream containing the alkaline fluid; and flowing the saturated flue gas stream containing the alkaline fluid through a venturi to cause the particulates in the flue gas to impact the alkaline fluid and react at least a portion of the sulfur dioxide with the alkaline fluid.

The present application provides a waste water preconditioning system for limiting mercury concentrations in a waste water stream resulting from treatment of a flue gas. The waste water preconditioning system may include a wet flue gas desulfurization system for treating the flue gas with an aqueous alkaline slurry, a sulfite detector to determine the concentration of sulfite in the aqueous alkaline slurry, and to produce the waste water stream with a mercury concentration of less than about five micrograms per liter. The waste water preconditioning system also may include a waste water treatment system downstream of the wet flue gas desulfurization system.

A system and a method for industrial plant or utility plant flue gas desulfurization, with zero waste water liquid discharge from a wet flue gas desulfurization system utilized therein, are disclosed herein. The wet flue gas desulfurization system is supplied an absorption liquid for contact with a flue gas to absorb flue gas acid gases. Waste water from the wet flue gas desulfurization system is heated under pressure in a heat exchanger to produce heated waste water, which is supplied to a flash vessel to produce steam. The produced steam is supplied to the flue gas upstream of a particulate collection system and the wet flue gas desulfurization system, supplied to the flue gas upstream of the wet flue gas desulfurization system, or supplied to absorption liquid circulated to the wet flue gas desulfurization system.