Texaco Inc.

Texaco Development Corporation

Albert Brent

Edward T Child

George N Richter

Charles P Marion

William B Crouch

Blake Reynolds

James R Muenger

Allen M Robin

Roger M Dille

Leigh R Middleton

Robert M Suggitt

Matthew A McMahon

Ronald J McKeon

Mitri S Najjar

Robert J Stellaccio

Jerrold S Kassman

A partial oxidation process and a novel burner are provided for simultaneously introducing two or three separate feedstreams into a free-flow partial oxidation gas generator for the production of synthesis gas and fuel gas, or reducing gas. The reactant feedstreams include a liquid hydrocarbonaceous fuel or a pumpable slurry of solid carbonaceous fuel, and a free-oxygen containing gas e.g. air or oxygen. The burner comprises a central conduit and a plurality of spaced concentric coaxial conduits with down-flowing annular passages. A flat annular-shaped disc or cup-shaped porous ceramic or porous metal cooling means of uniform composition, wall thickness and porosity with the various pores interconnecting is attached to the downstream tip of the burner. A controlled amount of liquid coolant under pressure is passed successively through the porous inside surface, porous core and porous outside surface of the cooling means is vaporized. The tip of the burner is thereby cooled. Stress cracking of the burner tip is prevented; and the life of the burner is extended. Further, deposition of ash on the face of the burner is prevented.

Partial oxidation process and burner with porous tip

Municipal sanitary sewage sludge is disposed of by an improved partial oxidation process without polluting the environment. Aqueous slurries of sewage sludge are upgraded by hydrothermal treatment, preferably while being sheared, concentrated, and then mixed with a supplemental fuel, preferably coal. A pumpable aqueous slurry of sewage sludge-coal and/or petroleum coke is thereby produced having a greater total solids and heat content (HHV) as well as containing an increased amount of sewage sludge for reacting with free-oxygen containing gas in a free-flow partial oxidation gas generator. Hot quench water or steam produced by cooling the hot raw effluent stream of synthesis gas, reducing gas or fuel gas from the gasifier may provide heat for the hydrothermal step.

Partial oxidation of sewage sludge

Municipal sanitary sewage sludge is disposed of by an improved partial oxidation process without polluting the environment. Aqueous slurries of sewage sludge are upgraded by being sheared without heating, concentrated if necessary, and then mixed with a supplemental fuel, preferably coal. In one embodiment, the aqueous slurry of sewage sludge and the supplemental coal and/or petroleum coke are introduced into a shearing mixer for simultaneous shearing and mixing together. A pumpable aqueous slurry of sewage sludge-coal and/or petroleum coke is thereby produced having an increased amount of total solids and an increased heat content (HHV) as well as containing an increased amount of sewage sludge for reacting with free-oxygen containing gas in a free-flow partial oxidation gas generator. Hot quench water or steam produced by cooling the hot raw effluent stream of synthesis gas, reducing gas or fuel gas from the gasifier may provide heat for indirect heat exchange with other streams in the process.

A control system for a partial oxidation process for continuously producing synthesis gas, fuel gas or reducing gas in which process one fuel is replaced by a different fuel without shutting down or depressurizing the gas generator. This multifuel process is not tied to one particular fuel and reacts slurries of solid carbonaceous fuel and/or liquid or gaseous hydrocarbonaceous fuels. Problems of fuel availability are reduced due to the wide selection of fuels that are suitable for the subject process. A two-section burner having a high turndown feature is employed that comprises a central conduit; a central bunch of tubes positioned in said central conduit; an outer conduit coaxial with said central conduit and forming an annular passage therewith; and an annular bunch of tubes positioned in said annular passage. The downstream ends of said central and/or annular bunches of tubes are respectively retracted upstream from the burner face a distance of about 0 to 12 i.e. 3 to 10 times the minimum diameter of the central exit orifice and the minimum width of the annular exit orifice. A control system is provided for switching the type of reactant fuel streams flowing through either one or both sections of the burner. The flow rates of the oxidant, fuel, and temperature moderator streams may also be varied in either one or both sections of the burner, thereby effecting a rapid turndown or turnup of the burner and a change in the production of the effluent gas.

Partial oxidation system

A partial oxidation control system for continuously producing synthesis gas, fuel gas or reducing gas in which one process fuel is replaced by a different fuel without shutting down or depressurizing the gas generator. Suitable burners for introducing the feedstreams into the gas generator comprise a central conduit means radially spaced from a concentric coaxial outer conduit having a downstream exit nozzle, and providing a coaxial annular passage means therebetween. The central conduit means may be retracted upstream from the burner face a distance of about 0 to 12 and preferably 3 to 10 times the minimum diameter of the central exit orifice. A premix zone is preferably provided comprising one or more, say 2 to 5 coaxial chambers in series where substantial mixing of the reactant streams and optionally volatilization of the slurry medium takes place. A control system is provided for switching the type of reactant fuel stream flowing through either the central conduit means or the annular passage means of the burner and adjusting the flow rates of the reactant stream of free-oxygen containing gas with or without mixture with a temperature moderator and if necessary to introduce supplemental H.sub.2 O into the reaction zone to maintain the temperature and weight ratio H.sub.2 O/fuel in the reaction zone at design conditions for the partial oxidation reaction without stopping production of the product gas.

Trim control of a partial oxidation gas generator for the production of synthesis gas, reducing gas, or fuel gas is effected by two improved control schemes which are automatically operated separately or in sequence. The control systems include sensors sensing the flow rate of the feedstreams and analyzers which provide signals corresponding to the wt. % carbon in the effluent gas quench cooling and scrubbing water for use in controlling the particulate carbon in the effluent gas stream, and/or signals corresponding to the mole fraction of CH.sub.4 (dry basis) in the cooled and cleaned effluent gas stream for use in controlling the temperature in the reaction zone. The signals from the sensors and analyzers are provided to the system control unit which computes values that represent the relative difference between the actual and desired carbon-make and/or the actual temperature in the reaction zone, and the relative difference between the actual and desired temperature in the reaction zone. The actual temperature is determined as a function of the methane concentration. These values are automatically compared with set point values and when adjustments are necessary, signals from the system control unit are provided to a flow rate regulating means which adjusts the flow rate of the free-oxygen containing gas by a small determined amount for control of the particulate carbon and/or to a flow rate regulating means which adjusts the flow rate of the temperature moderator by a small determined amount for control of the temperature in the reaction zone.

Trim control system for partial oxidation gas generator

Trim control of a partial oxidation gas generator for the production of synthesis gas, reducing gas, or fuel gas is effected by two improved control schemes which are automatically operated separately or in sequence. The control systems include sensors sensing the flow rate of the feedstreams and analyzers which provide signals corresponding to the wt. % carbon in the effluent gas quench cooling and scrubbing water for use in controlling the particulate carbon in the effluent gas stream, and/or signals corresponding to the mole fractions of CO.sub.2, CH.sub.4, CO and H.sub.2 (dry basis) in the cooled and cleaned effluent gas stream for use in controlling the temperature in the reaction zone. The signals from the sensors and analyzers are provided to the system control unit which computes values that represent the relative difference between the actual and desired carbon-make and/or the actual temperature in the reaction zone, and the relative difference between the actual and desired temperature in the reaction zone. The actual temperature is determined as a function of the methane equilibrium constant. These values are automatically compared with set point values and when adjustments are necessary, signals from the system control unit are provided to a flow rate regulating means which adjusts the flow rate of the free-oxygen containing gas by a small determined amount for control of the particulate carbon and/or to a flow rate regulating means which adjusts the flow rate of the temperature moderator by a small determined amount for control of the temperature in the reaction zone.

A burner and partial oxidation process for producing synthesis gas, fuel gas or reducing gas from slurries of solid carbonaceous fuel and/or liquid or gaseous hydrocarbon fuel. The burner has a high turndown feature and comprises a central conduit; a central bunch of parallel tubes that extend longitudinally through said central conduit; an outer conduit coaxial with said central conduit and forming an annular passage therewith; and an annular bunch of parallel tubes that extend longitudinally through said annular passage; and wherein the downstream ends of said central and annular bunches of parallel tubes are respectively retracted upstream from the burner face a distance of about 0 to 12 i.e. 3 to 10 times the minimum diameter of the central exit orifice and the minimum width of the annular exit orifice. Three ranges of flow through the burner may be obtained by using one or both bunches of tubes and their surrounding conduits. Throughput levels may be rapidly changed--up and down--without sacrificing stable operation. A control system is presented for varying the flow rates of the oxidant and fuel streams and/or for switching the reactant streams through one or both sections of the subject burner, thereby effecting a rapid turndown of the burner and in the production of the effluent gas.

Partial oxidation high turndown apparatus

A partial oxidation process and control system for continuously producing synthesis gas, fuel gas or reducing gas in which one process fuel is replaced by a different fuel without shutting down or depressurizing the gas generator. This multifuel process is not tied to one particular fuel and reacts slurries of solid carbonaceous fuel and/or liquid or gaseous hydrocarbonaceous fuels. Suitable burners for introducing the feedstreams into the gas generator comprise a central conduit means radially spaced from a concentric coaxial outer conduit having a downstream exit nozzle, and providing a coaxial annular passage means therebetween. The central conduit means may be retracted upstream from the burner face a distance of about 0 to 12 and preferably 3 to 10 times the minimum diameter of the central exit orifice. A premix zone is preferably provided comprising one or more, say 2 to 5 coaxial chambers in series where substantial mixing of the reactant streams and optionally volatilization of the slurry medium takes place. A control system is provided for switching the type of reactant fuel stream flowing through either the central conduit means or the annular passage means of the burner and adjusting the flow rates of the reactant stream of free-oxygen containing gas.

Partial oxidation process

A partial oxidation process for continuously producing synthesis gas, fuel gas or reducing gas in which process one fuel is replaced by a differing fuel without shutting down or depressurizing the gas generator. This multifuel process is not tied to one particular fuel and reacts slurries of solid carbonaceous fuel and/or liquid or gaseous hydrocarbonaceous fuels. Problems of fuel availability are reduced due to the wide selection of fuels that are suitable for the subject process. A two-section burner having a high turndown feature is employed that comprises a central conduit; a central bunch of tubes positioned in said central conduit; an outer conduit coaxial with said central conduit and forming an annular passage therewith; and an annular bunch of tubes positioned in said annular passage. The downstream ends of said central and/or annular bunches of tubes are respectively retracted upstream from the burner face a distance of about 0 to 12 i.e. 3 to 10 times the minimum diameter of the central exit orifie and the minimum width of the annular exit orifice. A control system is provided for switching the type of reactant fuel streams flowing through either one or both sections of the burner. The flow rates of the oxidant, fuel, and temperature moderator streams may also be varied in either one or both sections of the burner, thereby effecting a rapid turndown or turnup of the burner and a change in the production of the effluent gas.

High turndown partial oxidation process

Trim control process for partial oxidation gas generator

A process for the partial oxidation of pumpable slurries of solid carbonaceous fuels in which the pumpable slurry of solid carbonaceous fuel in a liquid carrier is passed in liquid phase through one passage of a burner comprising a retracted central coaxial conduit, an outer coaxial conduit with a converging orifice at the downstream tip of the burner and, optionally, an intermediate coaxial conduit. The downstream tips of the central conduit and the intermediate conduit, if any, are retracted upstream from the burner face a distance of respectively two or more say 3 to 10 for the central conduit, and about 0 to 12 say 1 to 5 for the intermediate conduit times the minimum diameter of the converging orifice of the outer conduit at the burner tip. A pre-mix zone is thereby provided comprising one or more, say 2 to 5 coaxial pre-mix chambers in series. The free-oxygen containing stream is passed through a separate passage of the burner into the pre-mix zone, in which mixing takes place with the slurry of solid carbonaceous fuel and liquid carrier. From 0 to 100, say about 2 to 80, volume % of the liquid carrier may be vaporized in the pre-mix zone. The multiphase mixture of reactants is then discharged into the reaction zone of the free-flow partial oxidation gas generator by way of the converging orifice of the outer conduit at the burner tip. Synthesis gas, fuel gas, or reducing gas is thereby produced.

Process for the partial oxidation of slurries of solid carbonaceous fuel

An apparatus in which a downflowing high pressure stream of hot raw synthesis gas from the reaction zone of a free flow partial oxidation gas generator at a temperature in the range of about 1800.degree. to 3000.degree. F. is passed through a first gas diversion and residue separation chamber contained in a first pressure vessel where the velocity of the gas stream is reduced, solid material and molten slag are separated by gravity from the gas stream, and the direction is diverted into a thermally insulated side transfer line. The hot gas stream is then passed through a thermally insulated gas-solids impingement separation means contained in a second pressure vessel where its direction and velocity is changed and additional residue is separated. The hot gas stream is then passed upwardly through a radiant cooler where additional solid matter is removed by gravity and the gas temperature is reduced to a temperature in the range of about 900.degree. to 1800.degree. F. By the subject apparatus, combustion residue may be removed from the raw stream of synthesis gas, and its sensible heat may be extracted at maximum temperature to produce by-product steam.

Growing community of inventors

Huntington, NY, United States of America

Albert Brent