Abstract: A system and process to re-liquefy boil-off liquid natural gas in varied amounts by a process using a screw compressor having an effective compression range from about 10 to about 100 percent of its rated capacity.

Abstract: A process for removing sulfur from a gas stream is provided in which a plurality of reactor units, each comprising a condenser and reactor, are selectively operable under Claus reaction and cold bed adsorption conditions. The arrangement of reactor units within the plant is periodically changed following a front-middle-back sequencing scheme. This ensures that the final reactor unit in the series utilizes fully cooled catalyst which is most efficient for operation under cold bed adsorption conditions. In addition, the condenser of the final reactor unit in the series operates at or below the freezing point of sulfur thereby permitting even greater sulfur recovery.

Abstract: An NGL recovery facility for separating ethane and heavier (C2+) components from a hydrocarbon-containing feed gas stream that utilizes a single, closed-loop mixed refrigerant cycle. The vapor and liquid portions of the feed gas stream are isenthalpically flashed and the resulting expanded streams are introduced into the NGL recovery column. Optionally, a second vapor stream can be flashed and then introduced into the recovery column at the same or lower separation stage than the flashed liquid stream. As a result, the NGL recovery facility can optimize C2+ recovery with compression costs.

Abstract: Apparatus and methods for recovering sulfur from acid gases. Acid gases containing relatively high amounts of carbonyl sulfide and/or one or more types of mercaptans can be treated in a sulfur recovery system employing an acid gas enrichment zone and a tail gas treatment zone, where partially-loaded sulfur absorbing solvent from the tail gas treatment zone is employed for sulfur absorption in the acid gas enrichment zone. Off-gas from the acid gas enrichment zone can be combined and hydrogenated with a sulfur recovery unit tail gas thereby increasing the total amount of sulfur recovery from the initial acid gas.

Abstract: A method and a system to produce a distillate stream from an aqueous stream containing at least one dissolved solid by a thermal distillation process using at least one of a heated aqueous stream from a turbine system intercooler and a stack heater as a heat source.

Abstract: An NGL recovery facility utilizing a single, closed-loop mixed refrigerant cycle for recovering a substantial portion of the C2 and heavier or C3 and heavier NGL components from the incoming gas stream. Less severe operating conditions, including a warmer refrigerant temperature and a lower feed gas pressure, contribute to a more economical and efficient NGL recovery system.

Abstract: A process and system is provided for separating a feed gas stream containing methane, at least one C2 component, at least one C3 component, and optionally heavier components, into a volatile gas stream containing a major portion of the methane and at least one C2 component and a less volatile stream containing a major portion of the at least one C3 and heavier components. The feed stream is cooled, at least partially condensed, and fed to a fractionation column wherein the feed stream is separated into an overhead vapor stream comprising primarily the lighter components of the feed stream and a bottoms liquid stream comprising primarily the heavier components of the feed stream. The introduction of a reboiler onto the fractionation column assists in removing co-absorbed C2 and lighter components from the fractionation column bottoms thereby facilitating more efficient operation of a downstream deethanizer column. Addition of residue recycle can further supplement recovery of desired components.

Abstract: A mixed single refrigerant process for separating a nitrogen gas stream from a natural gas stream containing nitrogen to produce a nitrogen gas stream from a liquefied natural gas stream wherein the separated nitrogen gas stream is used as a refrigerant for the natural gas stream and wherein the mixed refrigerant provides cooling for the process.

Abstract: A system and a method for recovering and increasing the pressure of seal leak gas for recycle or passage to further processing.

Abstract: Apparatus and methods for recovering sulfur from acid gases. Acid gases containing relatively high amounts of carbonyl sulfide and/or one or more types of mercaptans can be treated in a sulfur recovery system employing an acid gas enrichment zone and a tail gas treatment zone, where partially-loaded sulfur absorbing solvent from the tail gas treatment zone is employed for sulfur absorption in the acid gas enrichment zone. Off-gas from the acid gas enrichment zone can be combined and hydrogenated with a sulfur recovery unit tail gas thereby increasing the total amount of sulfur recovery from the initial acid gas.

Abstract: A method for producing hydrogen from a light hydrocarbon gas with the hydrocarbon gas being converted to particulate carbon and hydrogen and thereafter quenched with liquid sulfur with the purified hydrogen being recovered as a product.

Abstract: Multi-functional catalyst and processes utilizing the catalyst in single-stage conversion of syngas into hydrocarbon compounds are provided. The multi-functional catalyst, which comprises two or more catalytic materials situated within molecular distances of each other, facilitates conversion of syngas into one or more intermediate compounds and then into desired hydrocarbon compounds, such as high octane gasoline, diesel, jet fuel, olefins, and xylenes.

Abstract: An improved method for efficiently adding additional heat values into a distillation process to optimize the production of distillate from water.

Abstract: A quench column heater and a method for heating a circulating liquid in a gas-to-liquid heat exchanger and an indirect heat exchanger to produce a hot liquid stream for use for heat exchange in a selected process to supply heat to the process. One particularly useful application of the present invention is the revaporization of liquefied natural gas (LNG).

Abstract: A wastewater treatment process wherein a portion of a mixture of influent waste water and biomass are transferred from a first anaerobic region to a second anaerobic region having a relatively long retention time in order to produce additional very short chain fatty acids therein which are thereafter returned to the first anaerobic region so that biomass therein takes up the very short chain fatty acids. The contents of the first anaerobic region thereafter flow downstream into an aerobic region wherein the biomass takes up phosphorus. A portion of the biomass is returned to the first anaerobic region and a second portion of the biomass is wasted with phosphorus therein, thereby removing phosphorus from the wastewater being treated.

Abstract: A method for producing sulfur and energy from an acid gas stream containing hydrogen sulfide by partially combusting the acid gas stream to produce a combustion product gas, mixing a sulfur dioxide stream with the combustion product gas, separating sulfur from the mixture, combusting sulfur to produce sulfur dioxide and heat energy and passing at least a portion of the sulfur dioxide to the combustion product gas.

Abstract: A wastewater treatment process wherein a portion of a mixture of influent waste water and biomass are transferred from a first anaerobic region to a second anaerobic region having a relatively long retention time in order to produce additional very short chain fatty acids therein which are thereafter returned to the first anaerobic region so that biomass therein takes up the very short chain fatty acids. The contents of the first anaerobic region thereafter flow downstream into an aerobic region wherein the biomass takes up phosphorus. A portion of the biomass is returned to the first anaerobic region and a second portion of the biomass is wasted with phosphorus therein, thereby removing phosphorus from the wastewater being treated.

Abstract: A wastewater treatment process wherein a portion of a mixture of influent waste water and biomass are transferred from a first anaerobic region to a second anaerobic region having a relatively long retention time in order to produce additional very short chain fatty acids therein which are thereafter returned to the first anaerobic region so that biomass therein takes up the very short chain fatty acids. The contents of the first anaerobic region thereafter flow downstream into an aerobic region wherein the biomass takes up phosphorus. A portion of the biomass is returned to the first anaerobic region and a second portion of the biomass is wasted with phosphorus therein, thereby removing phosphorus from the wastewater being treated.

Abstract: An anaerobic digester for use in wastewater treatment systems having a fixed cover including a central tower for controlling gas and foam. A constant operating level is maintained in the digester by utilization of an overflow weir located in the tower. The fixed cover having an under flat surface that is in direct contact with contents of the digester. The tower has a number of spray nozzles that operably direct movement of foam toward discharge locations.

Abstract: An anaerobic digester for use in wastewater treatment systems having a fixed cover including a central tower for controlling gas and foam. A constant operating level is maintained in the digester by utilization of an overflow weir located in the tower. The fixed cover having an under flat surface that is in direct contact with contents of the digester. The tower has a number of spray nozzles that operably direct movement of foam toward discharge locations.