Abstract: A method and apparatus for predicting barriers to fluid flow in a subterranean reservoir using well data and 3-D seismic data are disclosed, where a preferred first step in the method models petrophysical properties of the reservoir to provide model logs which are expressible as continuous curves of a reservoir property as a function of depth. The next step selects individual data points on the continuous curves, which traverse a subterranean layer, and assigns a flow or nonflow state to each data point based on comparing a threshold value of a reservoir property with the value predicted by the data point. The layer is divided into a multitude of subvolumes each containing a single data point, and then a connectivity factor, which considers multiple flow paths around each data point, is calculated for each subvolume.

Abstract: An enclosure for housing electrical equipment is constructed to simplify use of general purpose electrical equipment at a location in a petroleum refinery which may contain combustible vapors. The construction provides an enclosure that is vapor tight except for an open front, thus providing user access and adequate ventilation to equipment such as a computer. In use a combustible gas monitor surveys the relatively small open area at the front of the enclosure and automatically disconnects electric current supplied to the general purpose rated equipment inside the enclosure on detection of a dangerous concentration of combustible gas entering through the front opening.

Abstract: A test fixture of the type that requires repeated manual lifting of weights in a drop-tube for performing an ASTM drop weight test, is provided with a computer automated pneumatically powered lift mechanism. The lift mechanism for the weights responds to a series of computer generated signals that are applied to a set of electropneumatic actuators for driving pistons to lift and drop the weight. Associated with the lift mechanism is a set opto-interrupter devices that generate a position signal representative of the position of the weight to be dropped as it ascends in the drop tube. In use the computer is provided with a desired drop height and essentially continuously compares the position signal with the desired drop height and releases the weight in the drop tube to impact a sample material when the position signal equals the desired drop height.

Abstract: A kinetic model for a catalytic cracking riser reactor is stored in a computer for simulating a hydrocarbon cracking reaction. The stored model describes a reactants, an intermediate, and a product species, which are lumped according to boiling range. Reaction rate constants for cracking the individual components of the lumping scheme are functions of a statistical technique known as "principal components," which are in turn linear combinations of bulk properties characterizing both catalyst and oil and are based on historical operating data for the riser reaction.

Abstract: In a cryogenic condensation scheme used for benzene removal in a process for liquefying natural gas, two series connected separation columns are provided with a feedstream precooled in a heat exchanger to a temperature that will at least condense the benzene component. In the first column, benzene is absorbed and vapor/liquid is separated with the liquid passed to the second column. The second column provides an overhead vapor stream conserved for processing to LNG, and a bottoms stream comprising NGL. The cooling for condensation of gaseous feed in the heat exchanger is controlled by automatically manipulating bypass flow around the heat exchanger responsive to measured vapor flow from the second separation column. Accordingly, the amount of liquid condensed is responsive to the flow rate of vapor withdrawn overhead from the second separation column.

Abstract: A method of modeling subsurface reservoir conditions deals with non-uniqueness of seismic reflection signals with respect to reservoir conditions by proposing and then comparing both seismic and lithologic data for forward model sites to select the most likely model for each site. Forward modeling techniques are used to build a synthetic seismic trace catalog, which includes a range of corresponding pseudo-logs for reservoir characteristics that could reasonably exist within a defined region. Then each synthetic seismic trace in the catalog is compared against every real seismic trace, and a number (e.g., 10 to 50) of synthetic traces is selected for association with each real trace that best match the real trace.

Abstract: In a heat exchange scheme associated with a gas purification column in an LNG recovery process, in which heat exchange is desired between fluids of such widely different temperatures that thermal shock could result in damage to heat exchanger apparatus, a control scheme compensates for the effect of excessive temperature differential. The desired compensation is achieved by manipulating flow in a heat exchanger bypass conduit for the warm fluid to maintain a desired temperature ratio between the colder fluid entering the heat exchanger and the warmer fluid exiting the exchanger. Additionally, start-up controls for the column include temporarily selecting temperature of a cold stream to automatically control opening of a valve to initiate flow of the warm stream.

Abstract: In a process for manufacture of a chemical product in which a plurality of individual reactant containing feedstreams are combined to form a mixed feedstream for a reactor, and wherein at least one of the plurality of feedstreams is subject to variations in reactant concentration, and another one of the plurality of feedstreams is essentially stable in reactant concentration, a desired ratio of relative reactant concentrations in the mixed feedstream is maintained by a control system which infers a reactant concentration ratio in the mixed feedstream based on process measurements and feed parameters related to the plurality of feedstock containing streams prior to their being combined. In use, flow rate of the feedstream which is essentially stable in reactant concentration is manipulated to maintain the inferred reactant concentrations in the mixed stream.

Abstract: In multistage refrigeration compression, where liquid refrigerant withdraw from a core-in-shell type heat exchanger connected to a high compression stage is passed to a similar exchanger connected to a lower compression stage, liquid level stability in the higher compression stage exchanger is improved by providing an enlarged surge volume. A baffle plate transversing a lower portion of the shell divides the shell into a cooling zone that contains the cores, and a discharge zone that is part of the surge volume. The height of the baffle is selected to facilitate maintenance of at least a minimum functional liquid level in the shell. Liquid refrigerant withdraw from the discharge zone of the high-stage shell is supplied to the cooling zone of a shell connected to a lower compression stage. The liquid level in the shell is maintained by manipulating flow to liquid refrigerant that is flashed into the cooling zone of the higher compression stage shell.

Abstract: Tubular lamp wells used to protect ultraviolet light producing lamps mounted in a photochemical reactor are continuously cleaned, while a reaction is being carried out, by containing a large number of small, chemically inert plastic pellets in the reaction solution. The plastic pellets are dispersed in the reaction solution and maintained in turbulent motion by a stirrer in the reactor. In use, the pellets frequently impact the outer surface of the tubular wells with sufficient momentum to prevent deposits of material, which could discolor the surface, from adhering on the tubular wells.

Abstract: In a process for manufacture of a chemical product, a reactive hydrocarbon feedstream, which varies in composition of the reactive component, is combined with a compatible but unreactive hydrocarbon feedstream to form a blended hydrocarbon stream which is then combined with a reactive alcohol stream of stable concentration of its reactive component, to form a complete feedstream to the reactor. A desired ratio of relative reactant concentrations in the complete feedstream to the reactor is maintained by a control system which maintains a stable concentration in the blended hydrocarbon stream by manipulating flow rate of the unreactive hydrocarbon feedstream responsive to a concentration measurement in the blended hydrocarbon stream. Flow ratio control is then applied to maintain a desired ratio of reactants in the complete feedstream for the reactor by calculating a flow ratio of the blended hydrocarbon stream to the reactive alcohol feedstream.

Abstract: The location in a wellbore of the top of a quantity of fill material which is sufficient to restrict flow in a tubing/casing annulus at a location deep in a well is determined by dropping a radioactive source through the annulus so that it falls to the top of the fill material. The depth of the thus deposited radioactive source is detected by radiation measurements, and the measured depth infers the location of the top of the fill material.

Abstract: An apparatus and method for producing ethylene polymer are provided which employ a conduit in the form of a closed loop (i.e. loop reactor) for receiving a flow of a monomer which includes ethylene, a polymerization catalyst and a diluent therethrough for the polymerization of the monomer to ethylene polymer. The conduit comprises at least one pipe constructed of rolled plate around which coolant fluid passes in heat exchange relationship.

Abstract: In withdrawing a reaction slurry from a polymerization reactor wherein solid particles in the slurry must be maintained in solution to prevent solidification, a redundant effluent line is provided to remove the slurry in the event the primary line becomes plugged. In use the primary and redundant lines are controlled in different manners such that a v-notch ball valve in the primary line is manipulated continuously to remove effluent while maintaining stable reactor conditions, and a control valve in the redundant line is manipulated intermittently as a backup for the primary control valve.

Abstract: Solid debris of rocks and scrap metal, etc., which are embedded in recoverable petroleum material such as solid or semisolid pitch or tar deposits, are separated from the petroleum material by a high pressure spray carried out in a closed separation vessel. The separation vessel includes a removable screen container for the solid petroleum material through which the material is sprayed with a heated liquid solvent using high pressure nozzles to melt and/or dissolve the pitch so that it flows through the screen container and is collected in a sump at the bottom of the separation vessel.

Abstract: A borehole technique for in-situ determination of principal stresses operating in a plane normal to the borehole includes using a downhole jack to independently initiate three spaced apart fractures in a subterranean formation, measuring the breakdown pressure required to initiate the fractures and then using the measured breakdown pressures in two-dimensional axial transformation equations to compute the maximum and minimum stresses that are active in the normal plane. The technique is useful while drilling the borehole by lowering a jack having three platens that can be independently activated to bear against the borehole wall along three radii which are offset from each other about the borehole axis. In use each platen is extended in turn to bear against the borehole wall until a fracture is initiated.

Abstract: In a distillation column, which for control purposes cannot tolerate the inherent dead time between analysis of consecutive samples in chromatograph analyzers, the chromatograph output is frequently corrected by inferring a dynamic correction based on the temperature change of a selected tray in the column. The dynamic correction applied to the distillation analyzer essentially eliminates the inherent dead time for obtaining a chromatograph analysis, and accordingly increased the rapidity of response of the column controls which rely on chromatograph analysis.

Abstract: In withdrawing a reaction slurry from a polymerization reactor wherein solid particles in the slurry must be maintained in solution to prevent solidification, a redundant effluent line is provided to remove the slurry in the event the primary line becomes plugged. In use the primary and redundant lines are controlled in different manners such that a v-notch ball valve in the primary line is manipulated continuously to remove effluent while maintaining stable reactor conditions, and a control valve in the redundant line is manipulated intermittently as a backup for the primary control valve.

Abstract: A method is provided by which the presence, if any, and location of a hydrocarbon reservoir or reservoirs adjacent to a subterranean surface can be determined based on DAD values which correspond to grid points of the surface. DAD values, specifically defined herein, relate to the change in seismic amplitude (Delta Amplitude) as divided by the Dip magnitude at each grid point. According to a preferred embodiment, colors are assigned to grid points based on the sign of the DAD values, and such assigned colors are plotted onto a depth/time contour map of the subterranean surface to result in a display which clearly indicates the location of any hydrocarbons.

Abstract: Process equipment is provided for separating ether, alcohol and hydrocarbon components from various etherifications of C.sub.4 or C.sub.5 isoolefins with an alcohol such as methanol or ethanol, and wherein identical process vessels are utilized for recovery of MTBE, ETBE, TAME, or TAEE. In use the process vessels are serially arranged in three zones. The first zone includes a first water wash vessel followed by a first fractionator and provides the ether product, the second zone includes a second wash vessel followed by a hydrocarbon stripper and recovers a stabilized hydrocarbon stream, the third zone includes a second fractionator which recovers an alcohol suitable for recycling.