Abstract: An improved gasification system, in which synthesis gas is produced through the operation of a fuel gas production bed comprising an upper layer (66) of organic input material, typically in the form of pellets or briquettes of substantially uniform size and configuration, two intermediate layers, one intermediate layer (70) for carbonizing the input material and the other intermediate layer (72) for partially oxidizing and substantially completely pyrolizing the input material and a lower layer (68) of tar-free charcoal. The gasification system includes a closed reaction chamber (10) which includes upper and lower portions (14/18). The cross-sectional area of the lower portion (18) is larger than the cross-sectional area of the upper portion (14), the lower portion further including an upper part which overlaps the lower part of the upper portion (14).

Abstract: In a rotary-grate gas producer operated under a pressure from 10 to 100 bars, the fuel constitutes a fixed bed, which slow descends. The mixture of gasifying agents contains water vapor and oxygen is supplied to the fixed bed through a rotary grate and through an ash layer, which is disposed on the rotary grate. In order to ensure that the ash will have a particle size in a desired range, a first pressure (p1) is measured below the rotary grate and a second pressure (p2) is measured approximately at the top of the ash layer. The pressure difference (p1-p2) is compared with a setpoint, which is associated with the current ratio of water vapor to oxygen in the mixture of gasifying agent. Said ratio is increased when the pressure difference is insufficient and the ratio is decreased if the pressure difference is excessive.

Abstract: This process pertains to a achieving high on-stream time and maintaining the temperature and composition of the raw effluent gas stream from a partial oxidation gas generator being fed simultaneously with a stream of gaseous fuel and separate stream of liquid hydrocarbonaceous fuel. Two parallel oxygen streams equipped with flow transmitters and control valves are used to supply the oxygen associated with two separate and different fuel streams. Each stream of oxygen is controlled by an O.sub.2 /fuel ratio control so that if the flow rate of either stream of fuel or its related oxygen stream changes, the oxygen/carbon atomic ratio of the remaining O.sub.2 and fuel stream in the gasifier is maintained at a desired value. Further, if either fuel flow is stopped, its associated O.sub.2 flow will stop, but the remaining fuel stream and its associated O.sub.2 stream will continue to flow at the same rate with no change in the oxygen/fuel weight ratio. Complete shut down of the unit is thereby avoided.

Abstract: The process for determining and controlling the fuel mass flow in partial oxidation and gasification of a fine-grained to powdery fuel includes particularly drawing the fuel from the supply vessel through a single outlet pipe and feeding the fuel to a distributor, in which a plurality of individual supply lines are connected to the individual burners, the fuel mass flow rate in the supply lines depending on the speed measured there and the radiometric density measurement being determined in the outlet pipe of the supply vessel. For control of the fuel mass flow a stepwise regulation depending on the crude gas flow produced in the gasification unit is thus provided.

Abstract: An improved gasification system, in which synthesis gas is produced through the operation of a fuel gas production bed comprising an upper layer (66) of organic input material, typically in the form of pellets or briquettes of substantially uniform size and configuration, two intermediate layers, one intermediate layer (70) for carbonizing the input material, and the other intermediate layer (72) for partially oxidizing and substantially completely pyrolyzing the input material and a lower layer (68) of tar-free charcoal. The length of the gas production bed from the top of the upper intermediate layer to the point where gas exits from the gas production bed is approximately at least 1.5 times the diameter of the bed, but not less than 7 feet. The removal of charcoal from the gas production bed is controlled and the operation of the bed otherwise controlled such that the charcoal produced during the process is activated carbon.

Abstract: An improved gas generator in which the composition of gas generated in a heated reactor is maintained when the flow rate from the reactor is adjusted. To accomplish this, the generator includes two diverting means responsive to the flow rate. The first diverts a portion of the reactant mixture before it enters the reactor, the diverted amount being insufficient to change the composition of the generated gas. The second diverts a portion of the generated gas to a burner for heating the reactor.

Abstract: A process for monitoring the conditions in the reaction zone of a gasifier in a process for the gasification of coal to produce synthesis gas is disclosed, the process being characterized by continual or periodic calculation of the rate of steam production by the heat exchange system of the gasifier, and comparison of the calculated rate with a pre-selected value.

Abstract: A gas accident preventive unit has a memory circuit which is capable of memorizing in advance a continuous service safety time according to a consumed gas volume of gas apparatuses that are installed at a gas user. The unit also includes a control circuit for sending out to an emergency shutoff valve, a close signal for cutting off the gas being supplied to the user in the event that any increase in gas flowrate is recognized in the previously measured value and the value measured this time by taking a measurement of the whole gas flowrate value being supplied to the gas user at a certain interval of time. The unit takes the measurement of continuous service hours on individual gas apparatuses or the gas apparatus having the largest gas consumption volume now under service, or responds to when the service of gas apparatus with the largest gas consumption volume being monitored has elapsed the continuous service safety time.

Abstract: This invention relates to a two-fluid nozzle which is adjustable to provide a substantially constant mixing energy. Adjustment of the two-fluid nozzle is made in accordance with the pressure and mass flow values of the liquid and gas fed to the nozzle. A microprocessor calculates the mixing energy from these values and provides an output to the nozzle to adjust it should its mixing energy be in variance with a pre-selected mixing energy.

Abstract: A method is provided for turning down from design conditions or below the output of raw product gas from a free-flow partial oxidation gas generator, or when operating below design conditions the output of raw product gas from the gas generator may be turned up while maintaining substantially constant the efficiency of the gas generation, or conversion of the fuel to gas, and the quality of the gas produced. The flow rates of the feedstreams to the burner are adjusted down or up a predetermined amount for each of the feedstreams to the burner to obtain a specified output of raw product gas while maintaining substantially constant in the reaction zone the levels of O/C atomic ratio and the H.sub.2 O/fuel weight ratio. Further, a pressure adjustment in the system is made which produces a corresponding adjustment to the pressure in the gas generator. The adjusted pressure is a direct function of the adjusted flow rate for the adjusted fuel or oxidant feedstream.

Abstract: Control process for producing an aqueous slurry of solid carbonaceous fuel having a desired solids concentration for feed to a partial oxidation gas generator by grinding together in a size reduction zone a recycle aqueous slurry stream comprising carbon-containing particulate solids, a stream of solid carbonaceous fuel, and a specific amount of make-up water. No valves are in the line or path between the size reduction zone and the feed tanks for the solid carbonaceous fuel and recycle aqueous slurry. A system control unit automatically calculates the amount of make-up water and provides a corresponding signal to control the flow rate. Input signals that are provided to the system control unit include those corresponding to the weigh belt feeder speed and moisture content for the solid carbonaceous fuel; and pump speed, weight fraction, temperature, and density of the solids for the slurry of recycle particulate solids.

Abstract: In a method for safely operating a coal gasifier which is indirectly cooled by passing a heat-carrying oil through a cooling jacket of the gasifier, the pressure of the heat-carrying oil is continually measured after having passed through the cooling jacket. If the measured pressure falls below a predetermined pressure, the supply of coal and gasifying agents to the gasifier is interrupted, the passage of heat-carrying oil is interrupted and water or steam is passed through the cooling jacket until the gasifier is safely shutdown.

Abstract: The fuel constitutes a fixed bed in the reactor, which is provided in its lower portion with a rotating grate, which is adapted to be speed-controlled. The gasifying agents consisting of oxygen, steam and/or carbon dioxide are introduced through the rotating grate into the fixed bed. Under the action of the rotating grate the incombustible mineral constituents are delivered as solid ash to a lock chamber container. The speed of the rotating grate is controlled in dependence on the temperature in the lock chamber container. The speed will be decreased when the temperature in the lock chamber container exceeds a desired value, and increased when the temperature is too low. The desired temperature in the lock chamber container is taken into account as a range, which varies with time. The speed can be controlled by hand or can be automatically controlled with the aid of a computer. The rate at which oxygen as a gasifying agent is supplied to the reactor is also taken into account in the speed control.

Abstract: A method is provided for turning down or up the output of raw product gas from a partial oxidation gas generator while maintaining in an acceptable range the efficiency of the gas generation, or conversion of the fuel to gas, and the quality of the gas produced. In the process, the flow rates for the separate feedstreams to the burner comprising fuel optionally in admixture with a temperature moderator, at least one stream of free-oxygen containing gas optionally in admixture with a temperature moderator, and with or without a separate feedstream of temperature moderator are adjusted down or up a predetermined amount to obtain a specified output of raw product gas while maintaining substantially constant in the reaction zone the levels of O/C atomic ratio and the temperature moderator/fuel weight ratio.

Abstract: Fuel and oxidant feed rates into a gasifier 202 are regulated by monitoring overall output 14 and comparing with a pre-selected setpoint valve 10. An overall load demand signal 50, responsive to this comparision is generated and used as an input to control 102 oxidant feed rate. The heating value of the product gas is measured 76 and used to control 64 overall fuel feed rate to the gasifier 202. For a two stage slagging gasifier, the present invention controls 114 fuel feed rate to the slagging stage 210 responsive to the measured slagging stage reaction temperature 128.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A reforming furnace having a radiant section containing cracking tubes, a convection section and a stack is controlled so as to maintain a desired synthesis gas temperature unless such maintenance would result in the violation of a process constraint. The desired excess oxygen concentration in the combustion gases withdrawn from the radiant section is also maintained while maintaining the desired synthesis gas temperature. As for the convection section, the temperature of a fluid stream passing through the convection section is maintained while still maintaining a desired excess oxygen concentration in the stack gas.

Abstract: An ash level control system is provided which incorporates an ash level meter to automatically control the ash bed level of a coal gasifier at a selected level. The ash level signal from the ash level meter is updated during each cycle that a bed stirrer travels up and down through the extent of the ash bed level. The ash level signal is derived from temperature measurements made by thermocouples carried by the stirrer as it passes through the ash bed and into the fire zone immediately above the ash bed. The level signal is compared with selected threshold level signal to determine if the ash level is above or below the selected level once each stirrer cycle. A first counter is either incremented or decremented accordingly. The registered count of the first counter is preset in a down counter once each cycle and the preset count is counted down at a selected clock rate.