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.

Disclosed is a desulfurizer of a fuel cell. The desulfurizer includes a pipe extended long and having one side that is open and the other side that is closed; a cap coupled to one side of the pipe and closing the pipe; a plurality of baffles installed in an inner space of the pipe and sequentially partitioning the inner space in a direction crossing a length direction of the pipe; an inflow pipe penetrating through the cap and the plurality of baffles and communicating from the outside of the pipe to the inner space of the pipe; and an outflow pipe installed in the cap and communicating the outside of the pipe and the inner space of the pipe.

Disclosed is a desulfurizer of a fuel cell. The desulfurizer includes a pipe extended long and having one side that is open and the other side that is closed; a cap coupled to one side of the pipe and closing the pipe; a plurality of baffles installed in an inner space of the pipe and sequentially partitioning the inner space in a direction crossing a length direction of the pipe; an inflow pipe penetrating through the cap and the plurality of baffles and communicating from the outside of the pipe to the inner space of the pipe; and an outflow pipe installed in the cap and communicating the outside of the pipe and the inner space of the pipe.

Disclosed is a desulfurizer of a fuel cell. The desulfurizer includes a pipe extended long and having one side that is open and the other side that is closed; a cap coupled to one side of the pipe and closing the pipe; a plurality of baffles installed in an inner space of the pipe and sequentially partitioning the inner space in a direction crossing a length direction of the pipe; an inflow pipe penetrating through the cap and the plurality of baffles and communicating from the outside of the pipe to the inner space of the pipe; and an outflow pipe installed in the cap and communicating the outside of the pipe and the inner space of the pipe.

A waste water processing system includes an upflow contacting column having a flue gas input for receiving flue gas having a temperature of at least 500 degrees F., a waste water input, and a flue gas output. The waste water input is coupled to a fluid injector, e.g., atomizing nozzles, positioned in the throat of a Venturi portion of the upflow contacting column or in a sidewall of the throat of the Venturi portion of the upflow contacting column. The flue gas in the upflow contacting column has a high velocity, e.g., a gas velocity exceeding 65 fps in the throat of the Venturi portion of the upflow contacting column at a position where the fluid injector is located. Drying additives such as recycled ash, lime, and/or cement may be, and sometimes are, input into the upflow contacting column downstream of the waste water input.

A gas treatment method includes an absorption step in which a gas to be treated containing an acidic compound, such as carbon dioxide, is brought into contact, in an absorber, with a treatment liquid that absorbs the acidic compound; and a regeneration step in which the treatment liquid, having the acidic compound absorbed therein, is sent to a regenerator, and the treatment liquid is then heated to separate the acidic compound from the treatment liquid. In the regeneration step, a gas almost insoluble to the treatment liquid, such as hydrogen gas, is brought into contact with the treatment liquid.

A catalytic composition is disclosed, which exhibits an X-ray amorphous oxide with a spinel formula, and crystals of ZnO, CuO, and at least one Group VIB metal oxide, and preferably, at least one acidic oxide of B, P, or Si, as well. The composition is useful in oxidative processes for removing sulfur from gaseous hydrocarbons.

A catalytic composition is disclosed, which exhibits an X-ray amorphous oxide with a spinel formula, and crystals of ZnO, CuO, and at least one Group VIB metal oxide, and preferably, at least one acidic oxide of B, P, or Si, as well. The composition is useful in oxidative processes for removing sulfur from gaseous hydrocarbons.

In some embodiments, the invention provides a method for converting of a flue gas desulfurization (FGD) waste product to a gypsum-enriched product by fostering growth of sulfur oxidizing bacteria (SOB) in the FGD waste product. Also provided are isolated sulfur oxidizing bacteria cultures as well as kits comprising an isolated sulfur oxidizing bacteria culture and written instructions for fostering the growth of the isolated sulfur oxidizing bacteria culture in FGD waste product to product a gypsum-enriched product.

In some embodiments, the invention provides a method for converting of a flue gas desulfurization (FGD) waste product to a gypsum-enriched product by fostering growth of sulfur oxidizing bacteria (SOB) in the FGD waste product. Also provided are isolated sulfur oxidizing bacteria cultures as well as kits comprising an isolated sulfur oxidizing bacteria culture and written instructions for fostering the growth of the isolated sulfur oxidizing bacteria culture in FGD waste product to product a gypsum-enriched product.