Multiphase Pumping

Microdroplet transport Microplug transport Multiphase pumping Thermal pumping... 

Microplug transport Microdroplet transport Thermal pumping Multiphase pumping... 

Pumping of liquids. Compression of gases Mixing (solids, liquids, gases possibly multiphase) Atomization, dispersion... 

Multiphase systems, solids, liquids and gases 181 Multiple stage pumps, vacuum producing 365 Multistage compression 353 ----number of stages 354... 

Triplett KA, Chiaasiaah SM, Abdel-Khahk SI, Sadowski JL (1999a) Gas-liquid two-phase flow in micro-channels. Part 1 two-phase flow patterns. Int J Multiphase How 25 377-394 Yuan H, Prosperetti A (1999) The pumping effect of growing and codapsing bubbles in a tube. Micromech Microeng 9 402-413... 

The role of mixing in heterogeneous reactions is obvious. In multiphase processes mixing imposed by a stirrer or an external pump is necessary to increase the interface through which reactants pass to meet their partner in the other phase and/or to intensify mass transfer between phases. Mixing can also play a significant role in the case of homogeneous reactions. Chemical reactions occur at the molecular level. Reactant molecules introduced into a reactor encounter the environment in the vicinity of the inlet. The composition of the mixture there is obviously... 

Naouri et al. (1991) described another contained fluidized bed, the so-called high compacting multiphasic reactor (HCMR), which they used for malic and lactic acid fermentations for wine improvement. Bioparticles were contained within a tapered region and liquid was rapidly recycled through this region by pumping improved liquid/solid contact was cited as the advantage of this reactor. 

Ruy et al. have performed a similar reaction under microreactor conditions in a multiphase solvent system containing an ionic liquid as the catalyst carrier and reaction promoter [35]. Their system consisted of two T-shaped micromixers (i.d. 1,000 and 400 pm) and a capillary stainless steel tube as an RTU (1,000 pm i.d. and 18 m length, giving a 14.1 ml volume), equipped with pumps and control valves. Under the optimized conditions, Pd-catalysed carbonylation of aromatic iodides in the presence of a secondary amine provided only the double carbonylated product, ot-ketoamide, while the amide obtained by the single carbonylation was observed in high quantities only when the reaction was performed in batch (Scheme 13). 

In multiphase reactors we frequently exploit the density differences between phases to produce relative motions between phases for better contacting and higher mass transfer rates. As an example, in trickle bed reactors (Chapter 12) liquids flow by gravity down a packed bed filled with catalyst, while gases are pumped up through the reactor in countercurrent flow so that they may react together on the catalyst surface. 

A wide range of motionless (static) mixers is available on the market (Figure 3). They are pipe inserts that generate radial mixing (i.e., across the pipe) and (for multiphase systems) interfacial surface area (e.g., to produce fine bubbles or droplets). The energy for mixing is extracted from the mean flow as such, an extra pumping... 

Lo [51] simulated two- and three phase isothermal non-reacting stirred tanks with two downward pumping 45o pitched -blade disc turbines and one curved-blade impeller at the bottom. Four or six baffles were placed at equal distance around the vessel wall. An Eulerian multiphase-population balance (MUltiple-SIze-Group, MUSIG) model was used as implemented in CFX. Turbulence of the continuous phase was modeled by the standard k-e turbulence model, and an algebraic relation was used for the particle induced eddy vis-... 

This is a handbook on containment of ground water contamination. In situ treatment, and contaminant removal. It discusses subsurface fate and transport processes, ground water and contaminated soils bioremediation, ground water pump-and-treat technologies. soil vapor extraction, and multiphase contamination and free product recovery. 

NE-1000 Multiphase Programmable Pumps (New Era Pump Systems, Farmingdale, NY) (15) or peristaltic pump to replace the volume of BSS in the chamber every 15 s (see Note 2). 

Perfusion chamber such as the Sykes-Moore chamber see Subheading 2.3, item 2). This chamber works well in confocal or multiphoton microscopy when used with quartz coverslips (SPI Supplies Division of Structure Probe Inc., West Chester PA http //www.2spi.com) for improved stability during perfusion and the NE-1000 Multiphase Programmable Pump (New Era Pump Systems, Farmingdale, NY) see Subheading 2.3, item 3). 

Reasonably, the corrosion form is typical at relatively high velocities between the material surface and flie fluid, and it is particularly intensive in cases of two-phase or multiphase flow, i.e. hquid-gas and liquid-solid particle flow. Components often liable to erosion corrosion are propellers, pumps, turbine parts, valves, heat exchanger tubes, nozzles, bends, and equipment exposed to liquid sputter or jets. Most sensitive materials are those normally protected by corrosion products with inferior strength and adhesion to flie substrate, e.g. lead, copper and its alloys, steel, and under some conditions aluminium/aluminium alloys. Stainless steel, titanium... 

Extent of reaction specified Two-phase, chemical equilibrium Multiphase, chemical equilibrium Continuous-stirred tank reactor Plug-flow tubular reactor Pump or hydraulic turbine Compressor or turbine Pressure drop in a pipe Stream multiplier Stream duplicator... 

Separation vessels can be found in most chemical plants and are used to separate inlet streams into different phases. See Figure 14-9. In the chemical industries it is common to find inlet streams consisting of a liquid with entrained gas at a high pressure. As the multiphase stream enters the separator the temperature and pressure decreases. This causes the gas and liquid to separate. The liquid level in the separator is normally controlled by a level control loop in e BPCS and is normally continuously pumped to another vessel for further processing. The gas exiting the top of the vessel is normally compressed and distributed. 

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