Standard Oil Company (indiana)

Amoco Corporation

The Standard Oil Company

Robert L Reed

John W Palm

Clifton S Goddin, Jr

Luther E Petty

Truman P Moote

Ralph G Ruth

David A Holdeman

Oxygen feed to a Claus plant is controlled by calibrating a hydrocarbon-representative response signal, but not a hydrogen sulfide representative response signal, responsive to the ratio of hydrogen sulfide:sulfur dioxide in effluent from the Claus plant.

Method for controlling claus furnace with variable hydrocarbon feed

Sulfur is recovered from an acid gas stream comprising hydrogen sulfide by successively reducing the hydrogen sulfide in a thermal reaction zone, a first position Claus catalytic conversion zone operated above the sulfur deposition point, and a second position Claus catalytic conversion zone operated under conditions effective for producing and depositing elemental sulfur on the catalyst. Periodically, the reactor in the second position is switched to the first position, the reactor in the first position having previously been preconditioned thereby avoiding a temporary increase in emissions after switching.

Two-reactor, high-recovery sulfur plant and process

Modified Claus furnace containing, in addition to primary reaction chamber, a secondary chamber in heat exchange with said primary reaction chamber wherein H.sub.2 S is cracked to supply hydrogen needed downstream in a clean-up system. This eliminates the need for supplemental hydrogen generator now usually provided for in a sulfur recovery system. A catalyst such as cobalt-molybdenum can be used in the secondary reaction chamber.

Modified Claus furnace

A straight-through three reactor system and process produces acceptable levels of sulfur recovery from acid gas at a cost significantly less than that required for a standard modified four reactor Claus system. The system includes two conventional Claus reactors and one cold bed adsorption (CBA) reactor in series. Four condensers are provided, one disposed before each of the catalytic reactors, and one disposed after the CBA reactor. The system is designed to operate either in a recovery mode or in a regeneration mode. In the recovery mode, the reactors are in series and the last reactor is operated below dew point of sulfur (CBA reactor). In regeneration mode, effluent from the third condenser is heated in a first heat exchanger where effluent from the first catalytic reactor is used as the heat source. Sulfur is vaporized in the CBA reactor and is recovered in the fourth condenser. Effluent from the fourth condenser is then passed to an incinerator.

Process and system for producing and recovering elemental sulfur

A system and process produce high actual levels of sulfur recovery from acid gas. The system includes two conventional Claus reactors and two cold bed adsorption (CBA) reactors. Four condensers are provided, one disposed before each of the catalytic reactors, and one disposed after the CBA reactor. The system includes a gas clean-up treatment zone for hydrogenation, drying and oxidation of gas to provide stoichiometric ratio of H.sub.2 S and SO.sub.2. The gas is passed through the clean-up treatment zone prior to being fed to the first of the CBA reactors. The system is designed to operate either in a recovery mode or in a regeneration mode. In the recovery mode, the reactors are in series and the CBA reactors are operated below dew point of sulfur. In regeneration mode, effluent from the clean-up treatment zone is heated in a heat exchanger using effluent from the first catalytic reactor as the heat source. The resulting regeneration gas is fed to one of the two CBA reactors to vaporize sulfur and regenerate the catalyst. The vaporized sulfur is recovered in the condenser. The effluent from the condenser is passed to the other CBA reactor which is operated in the recovery mode during regeneration.

Process for producing and recovering elemental sulfur from acid gas

Magnesium is removed from brine by contacting the brine with calcium hydroxide at temperatures above about 80.degree. C. but below the boiling point of the brine. The contacting results in the formation of magnesium hydroxide precipitate which is substantially insoluble in the mother liquor at those temperatures and strontium hydroxide which is dissolved in the mother liquor. When the contacting is carried out at a temperature above about 90.degree. C., magnesium hydroxide precipitate is fast settling and filterable; accordingly, it is removed from the mother liquor by a conventional process, such as filtering. The mother liquor is then cooled to cause the precipitation of at least a substantial part of strontium hydroxide present in the mother liquor. The precipitate of strontium hydroxide is recovered by a conventional process such as filtering. If precipitation upon cooling is insufficient, carbon dioxide gas is introduced into the mother liquor to effect the precipitation of strontium hydroxide. Barium can be removed and recovered in the form of barium sulfate by reacting the remaining mother liquor with sodium sulfate. In order to produce a faster-settling precipitate of magnesium hydroxide, the brine is contacted with a sufficient amount of a solution or slurry of calcium hydroxide in water to bring the concentration of magnesium in the resulting liquid to the range from about 0.023 mols of magnesium per liter to about 0.04 mols of magnesium per liter.

Removal and recovery of magnesium, strontium and barium from brines

A straight-through four reactor system and process is disclosed for obtaining high levels of sulfur recovery from acid gas at a cost equal to or less than that required for a standard modified four reactor Claus system. Two conventional Claus reactors and two cold bed adsorption (CBA) reactors are in series. Four condensers are provided, one disposed before each of the Claus and CBA catalytic reactors. A first heater and a first bypass line is disposed between the second condenser and the second catalytic reactor (second Claus reactor) and a second heater and a second bypass line is disposed between the third condenser and the third catalytic reactor (first CBA reactor). The system is designed to operate either with both CBA reactors in a recovery mode or with one CBA reactor in a regeneration mode and the other CBA reactor in a recovery mode. When both reactors are operating in the recovery mode, the system is similar to the standard modified Claus system. But when one of the CBA reactors is in a regeneration mode, effluent from the third condenser is heated in the second heater and directed to the CBA reactor on regeneration. Sulfur is vaporized from the regenerating CBA reactor and is recovered in the fourth condenser. Effluent from the fourth condenser is then passed through the CBA reactor in recovery mode before it passes to the incinerator.

System and process for producing and recovering elemental sulfur

Excess heat generated in a thermal reaction zone of a Claus sulfur recovery plant is used, by means of a high boiling point heat transfer medium, to reheat the Claus plant process stream prior to high temperature Claus catalytic conversion, and/or to regenerate Claus catalyst on which sulfur is deposited, or for other functions. In another aspect, low temperature Claus catalytic converters are operated at equivalent pressures during a cycle comprising an adsorption phase, a regeneration phase, and a cooling phase.

Recovery of elemental sulfur from sour gas

Claus process sulfur recovery can be improved by performing a Claus conversion under low temperature and low water concentration conditions. The process treats a feed stream containing sulfur compounds by conversion of all sulfur components to hydrogen sulfide, water removal to low water concentrations, creation of a Claus reaction mixture, and then low temperature catalytic conversion to sulfur and water.

Low temperature Claus process with water removal

Ammonium compounds deposited on catalyst in a sulfur recovery facility are removed by passing a hot regeneration stream in contact with the catalyst to produce a regeneration effluent stream containing ammonia followed by combustion or catalysis to reduce the concentration of ammonia in the regeneration effluent stream.

Method and apparatus for reducing the ammonia concentration of sulfur

Claus-type processes used in the past to recover sulfur from low H.sub.2 S acid gas, in the presence of hydrocarbon or other impurities which are harmful to the Claus catalyst, have required the use of straight-through operation with the burning of supplemental fuel gas to maintain the required combustion temperature in the furnace. A method for conserving the amount of additional fuel gas required involving utilization of the excess heat of combustion to preheat the acid gas and oxygen-containing streams to a temperature in excess of 600.degree. F prior to combustion is described. Additional energy savings are achieved by preheating the Claus tail gas effluent prior to incineration.

Growing community of inventors

Tulsa, OK, United States of America

Robert L Reed