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Cross flows

In situations where a low concentration of suspended solids needs to be separated from a liquid, then cross-flow filtration can be used. The most common design uses a porous tube. The suspension is passed through the tube at high velocity and is concentrated as the liquid flows through the porous medium. The turbulent flow prevents the formation of a filter cake, and the solids are removed as a more concentrated slurry. [Pg.74]

To type crude oils (see Figure 2.13). This method uses an extremely accurate compositional analysis of crudes to determine their source and possible migration route. As a result of the accuracy It is possible to distinguish not only the oils of individual accumulations in a region, but even the oils from the different drainage units within a field. If sufficient samples were taken at the exploration phase of a field, geochemistry allows one to verify cross flow and preferential depletion of units during later production. [Pg.25]

Fault seals are known to have been ruptured by excessive differential pressures created by production operations, e.g. if the hydrocarbons of one block are produced while the next block is kept at original pressure. Uncontrolled cross flow and inter-reservoir communication may be the result. [Pg.84]

Keywords production decline, economic decline, infill drilling, bypassed oil, attic/cellar oil, production potential, coiled tubing, formation damage, cross-flow, side-track, enhanced oil recovery (EOR), steam injection, in-situ combustion, water alternating gas (WAG), debottlenecking, produced water treatment, well intervention, intermittent production, satellite development, host facility, extended reach development, extended reach drilling. [Pg.351]

Cross flow inside the casing can also be prevented by isolating one zone. However, this may still result in reduced production. Installing a selective completion can solve the problem but is an expensive option. To repair cross flow behind casing normally requires a full workover with a rig. Cement has to be either squeezed or circulated behind the production casing and allowed to set, after which cement inside the casing is drilled out, and the producing zones perforated and recompleted. [Pg.356]

The drop in pressure when a stream of gas or liquid flows over a surface can be estimated from the given approximate formula if viscosity effects are ignored. The example calculation reveals that, with the sorts of gas flows common in a concentric-tube nebulizer, the liquid (the sample solution) at the end of the innermost tube is subjected to a partial vacuum of about 0.3 atm. This vacuum causes the liquid to lift out of the capillary, where it meets the flowing gas stream and is broken into an aerosol. For cross-flow nebulizers, the vacuum created depends critically on the alignment of the gas and liquid flows but, as a maximum, it can be estimated from the given formula. [Pg.141]

Using Poiseuille s formula, the calculation shows that for concentric-tube nebulizers, with dimension.s similar to those in use for ICP/MS, the reduced pressure arising from the relative linear velocity of gas and liquid causes the sample solution to be pulled from the end of the inner capillary tube. It can be estimated that the rate at which a sample passes through the inner capillary will be about 0.7 ml/min. For cross-flow nebulizers, the flows are similar once the gas and liquid stream intersection has been optimized. [Pg.141]

The flows of gas and liquid need not be concentric for aerosol formation and, indeed, the two flows could meet at any angle. In the cross-flow nebulizers, the flows of gas and sample solution are approximately at right angles to each other. In the simplest arrangement (Figure 19.11), a vertical capillary tube carries the sample solution. A stream of gas from a second capillary is blown across this vertical tube and creates a partial vacuum, so some sample solution lifts above the top of the capillary. There, the fast-flowing gas stream breaks down the thin film of sample... [Pg.144]

In the cross-flow arrangement, the argon gas flows at high linear velocity across the face of an orthogonal capillary tube containing sample solution. The partial vacuum causes liquid to lift above the end of the capillary. Here, it meets the argon and is nebulized. [Pg.144]

In this cross-flow arrangement, a thin film of sample solution is obtained as it flows around the edge of a small opening, through which there is a fast linear flow of argon. The liquid film is rapidly nebulized along the rim of the orifice. [Pg.145]

The aim of breaking up a thin film of liquid into an aerosol by a cross flow of gas has been developed with frits, which are essentially a means of supporting a film of liquid on a porous surface. As the liquid flows onto one surface of the frit (frequently made from glass), argon gas is forced through from the undersurface (Figure 19.16). Where the gas meets the liquid film, the latter is dispersed into an aerosol and is carried as usual toward the plasma flame. There have been several designs of frit nebulizers, but all work in a similar fashion. Mean droplet diameters are approximately 100 nm, and over 90% of the liquid sample can be transported to the flame. [Pg.146]

The advantage of single-pass over cross-flow filtration is that it is an easier system to operate and can be cost effective, particularly if the product to be filtered is expensive, because very tittle of the initial fluid is lost during filtration. However, because the flow pattern of the fluid is directly through the filter, filter life maybe too short for the fluid being filtered. The minimum flow rate needed downstream of the filter must also be considered, especially when there are time constraints to the process. In some situations it may be more advantageous to use a cross-flow system where higher flow rates may be easier to obtain. [Pg.143]

Mechanical Cake Removal. This method is used in the American version of the dynamic filter described under cross-flow filtration with rotating elements, where turbine-type rotors are used to limit the cake thickness at low speeds. The Exxflow filter, introduced in the United Kingdom, is described in more detail under cross-flow filtration in porous pipes. It uses, among other means, a roUer cleaning system which periodically roUs over a curtain of flexible pipes and dislodges any cake on the inside of the pipes. The cake is then flushed out of the curtain by the internal flow. [Pg.409]

Cross-Flow Filtration in Porous Pipes. Another way of limiting cake growth is to pump the slurry through porous pipes at high velocities of the order of thousands of times the filtration velocity through the walls of the pipes. This is ia direct analogy with the now weU-estabHshed process of ultrafiltration which itself borders on reverse osmosis at the molecular level. The three processes are closely related yet different ia many respects. [Pg.412]

The idea of ultrafiltration has been extended ia recent years to the filtration of particles ia the micrometer and submicrometer range ia porous pipes, usiag the same cross-flow principle. In order to prevent blocking, thicker flow channels are necessary, almost exclusively ia the form of tubes. The process is often called cross-flow microfiltration but the term cross-flow filtration is used here. [Pg.412]

Other iavestigations of cross-flow filtration iaclude the study of the coaceatratioa of bacteria (41), the coaceatratioa of fermentation cell debris (42), the coaceatratioa of electrocoatiag paiat (43), the chemical effects oa cross-flow filtratioa of primary sewage efflueat (44), and the use of tubes of different materials, dimensions, and porosity with several slurries (45). [Pg.412]

A. E. Ostermann and E. Pfleiderer, "AppHcation of the Principle of Cross-Flow in SoHd/Liquid Microfiltration," in the Proceedings of the Symposium on Economic Optimi tion Strategy in SolidjFiquid Separation Processes, SocifitH Beige de Filtration, Louvaine-la-Neuve, Belgium, Nov. 1981, pp. 123-138. [Pg.415]

Fig. 18. Jet trajectory of a round jet in bounded cross flow where J = Pj V j p (a) flow geometry, ratio of height of tunnel to diameter of injection tube HID) = 12 and (b) flow streamlines where the data points are experimental deterrninations and the lines correspond to calculated predictions for (—)... Fig. 18. Jet trajectory of a round jet in bounded cross flow where J = Pj V j p (a) flow geometry, ratio of height of tunnel to diameter of injection tube HID) = 12 and (b) flow streamlines where the data points are experimental deterrninations and the lines correspond to calculated predictions for (—)...

See other pages where Cross flows is mentioned: [Pg.166]    [Pg.119]    [Pg.246]    [Pg.354]    [Pg.144]    [Pg.145]    [Pg.145]    [Pg.146]    [Pg.261]    [Pg.44]    [Pg.50]    [Pg.143]    [Pg.386]    [Pg.386]    [Pg.402]    [Pg.406]    [Pg.409]    [Pg.387]    [Pg.387]    [Pg.409]    [Pg.409]    [Pg.409]    [Pg.412]    [Pg.412]    [Pg.103]    [Pg.528]    [Pg.530]    [Pg.580]   
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Absorption cross-flow

Adsorption cross-flow systems

Adsorption with Cross Flow of Gas and Adsorbent Phases

Baffle condenser, cross flow

Batch processes cross flow

Bubbles cross-flow filtration

Coalescers cross-flow devices

Compressible flow cross section

Converter types Cross flow

Cooling cross-flow

Cooling towers cross-flow tower

Critical heat flux in cross flow

Cross Channel Flow in a Single Screw Extruder

Cross flow cylinders

Cross flow model

Cross flow over cylinders

Cross flow over spheres

Cross flow pattern

Cross flow spheres

Cross flow tube banks

Cross flow, airflow

Cross flow, monolithic reactor

Cross flows boiling

Cross-Coupling in a Flow Microreactor

Cross-Flow Model for Gas Separation by Membranes

Cross-channel flow

Cross-current flow

Cross-equatorial flow

Cross-flow absorber operation

Cross-flow area

Cross-flow centrifugal

Cross-flow conditions

Cross-flow configuration

Cross-flow configuration membrane separation

Cross-flow extraction

Cross-flow filters

Cross-flow filtration downstream processing

Cross-flow filtration reactor

Cross-flow filtration techniqu

Cross-flow heat exchanger

Cross-flow heat exchanger-reactors

Cross-flow in pervaporation

Cross-flow membrane

Cross-flow membrane cassette

Cross-flow membrane emulsification

Cross-flow membrane modules

Cross-flow micro reactor

Cross-flow microfiltration

Cross-flow microfiltration systems

Cross-flow monolith fuel cell reactor

Cross-flow nebulisers

Cross-flow nebulizers

Cross-flow operation

Cross-flow operation mode, modules

Cross-flow plates

Cross-flow process

Cross-flow reactor

Cross-flow recuperators

Cross-flow scrubber

Cross-flow solid state electrochemical

Cross-flow system, direct membrane

Cross-flow type membrane oxygenator

Cross-flow ultrafiltration

Cross-flow ultrafiltration system

Cross-flow velocity

Cross-flow velocity adjustment

Cross-flow velocity calculating

Cross-flow velocity exchangers

Cross-flow velocity gradient

Cross-flow velocity impact

Cross-flow velocity shell-side

Cross-flow/tangential filtration

Cyclone cross-flow injection

Cylinders in cross flow

Downstream cross-flow filtration

Dynamic cross-flow filter systems

Effect of Cross-Flow

Electric field, separations based cross-flow

Electrochemical reactors, cross-flow

Electrochemical reactors, cross-flow solid state

Electrofiltration cross-flow

Electrolyte resistivity, cross-flow

Extraction process cross-flow

Filtration cross-flow

Flow cross-coupling

Flow diagram of the manufacturing process for polyolefin foams using radiation cross-linking

Flow in a Tube of Arbitrary Cross-Section

Flow-through diffusion cells, cross-section

Fluidized beds cross flow ratio

Fracture cross flow

Fracture cross flow measurements

Friction factors cross-flow tube banks

Gas separation under cross-flow conditions

Heat cross-flow

Hot Wall Cross-Flow Reactor

Hydrogen cross-flow

Importance of Shell-Side Cross-Flow

Jet in cross flow

Liquid separation membranes cross flow filtration

Maximum flow rate in a pipe of constant cross-sectional

Membrane separation cross-flow filtration

Microfiltration cross-flow configuration

Microfiltration cross-flow filtration

Mini cross-flow

Mixer cross-flow

Net electron flow across a geometric cross-section

Newtonian flow, pipe, circular cross-section

Oxidation reaction, cross-flow

Poiseuille flow in tubes of circular cross-section

Polymer cross-flow

Reactors with two process streams in cross flow

Rectangular cross-flow module

Reverse osmosis cross-flow filtration

Reversed, Mixed, or Cross-Flow

Safety narrowest flow cross section

Scaling cross-flow filtration

Separation cross flow

Shell-side cross-flow

Shell-side cross-flow importance

Sieve tray vapor cross-flow channeling

Solid energy balance, cross-flow

Solid-liquid separation cross-flow filtration

Solid/liquid separation cross-flow filters

Spiral heat exchanger cross-sectional flow diagram

Sprayers cross-flow

Thermal design cross-flow

Time-pulsing cross-flow mixer

Trays cross-flow pattern

Tubular cross flow reactor

Turbulent Flow in Straight, Smooth Ducts, Pipes, and Tubes of Circular Cross Section

Turbulent Flow in a Tube of Circular Cross-Section

Ultrafiltration cross-flow configuration

Vapor cross flow

Viscous cross-flow

Viscous cross-flow dependence

Viscous cross-flow sensitivities

Viscous cross-flow simple model

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