Pump drive

The total pump power input Ppi is the net power delivered to the pump drive shaft by the prime mover system. This is... 

Type of drive Power range (kW) Speeds Drive efficiency (%) Overall efficiency (%) including motor Power factor Main characteristics related to pump drives... 

Mitochondria maintain or accumulate cations such as K, Na, Ca, and Mg, and Pj. It is assumed that a ptimaty ptoton pump drives cation exchange. 

Throttling the flow results in an energy loss, which is acceptable in most applications. However, when the flow-rates are large, the use of variable speed control on the pump drive should be considered to conserve energy. 

The major disadvantage in using heat transfer enhancement is that it increases the pressure drop. In retrofit, this can be important, as the pumps driving the flow might be limited in their capacity to meet the required increase in pressure drop. 

Also, as discussed in Chapter 15, rather than install additional heat transfer area to cater for the new operational requirements, heat transfer enhancement can be considered. Changes to the number of tube passes or the baffle arrangement might allow the heat transfer coefficient to be enhanced. Alternatively, tube inserts could be used. This was discussed in Chapter 15. The major disadvantage in using heat transfer enhancement is that it increases the pressure drop. In retrofit this can be important, as the pumps driving the flow might be limited in their capacity to meet the required increase in pressure drop. 

Bearing housings shall be arranged so that bearings can be replaced without disturbing pump drives or mountings. 

Figure 16.14. Three types of crystal purifiers with different ways of transporting the crystals, (a) Spiral or screw conveyor type, laboratory scale, but successful up to 200 mm dia [Schildknecht, Z. Anal. Chem. 181, 254 (1961)). (b) Philips purifier with reciprocating piston or pulse pump drive [McKay, Dale, and Weedman, Ind. Eng. Chem. 52, 197(I960)], (c) Combined crystallizer and purifier, gravity flow of the crystals purifier details on the right (Brodie, 1971).

The pump induced transient polarisation of the medium modifies the polarisation state of a time delayed probe pulse. Phenomenologically, this process can be regarded as a transient pump induced linear or circular birefringence, also called the Specular Optical Kerr Effect (SOKE) and the Specular Inverse Faraday Effect (SIFE) [18], These are cubic non-linear effects and are predicted to exist from symmetry arguments. Both effects consist of coherent and incoherent parts. For the coherent part, the pump drives the coherent electron-hole pair that affects the probe polarisation. The effect depends upon the probe phase relative to that of the electron-hole pair, and hence, that of the pump. For the incoherent part of the SIFE and the SOKE, the relative pump-probe phase is not important, since the probe pulse polarisation is modified by the pump induced sample polarisation that survives after the decoherence of the electron-hole pair. 

This simple calculation indicates that if H+ were passively distributed across the plasma membrane, and for a mean membrane potential of-60 mV, intracellular pH values (pHi) would be expected to be 1 pH unit lower than the external pH values (pHo). Numerous experiments performed on a large variety of cells indicate, however, that pHi values are usually close to pHo values, or slightly below (Roos and Boron, 1981). This implies that H+ ions are not passively distributed across the plasma membrane and that H+ pumps drive H+ out of equilibrium. Different H+ pumps have been identified in eukaryotic cells an ubiquitous Na+/H+ exchanger, and pumps that have a more restricted cellular distribution. These are (H+)ATPases,... 

Gaggioli, R.A. and Fehring, T., "Economics of Boiler Feed Pump Drive Alternatives", Combustion, 49, 9 (1978), 35-39. 

In the MiniMed implantable pump, a piston pump drives insulin through the delivery catheter. A patented solenoid motor controls the piston movement, to aspirate insulin from the reservoir chamber into the piston chamber and then push it through the insulin delivery catheter. 

Figure 6.27 Pressurized squirrel cage motor as a water injection pump drive. Type of protection EEx p IIT3 Rated power 2500 kW Rated voltage 11 kV Rated frequency 50 cps Rated speed 2986 min-1.

VENDOR IS TO QUOTE MOST ENERGY-EFFICIENT PUMP-DRIVE COMBINATION AS ALTERNATE IF DIFFERENT THAN UNIT(S) OFFERED. 

Suction pressure at the pumps is atmospheric the pump head exclusive of line friction is 120 psi. Pump efficiency is 71%. Material of construction ofline and pumps is 316 SS. Operation is 8000hr/yr. Characteristics of the alternate pump drives are ... 

Membranes are asymmetrically oriented pumps drive transport in one direction receptors bind molecules on the outside... 

Specifications for equipment have also in the past been very detailed, primarily to avoid the problems that would occur if bidders intended to use cement grout pumps for chemical grouting. Most often, the described details cover a page or more, with separate paragraphs dealing with capacity (pressure and volume), materials of construction, number of pumps, drive systems, and control systems including gel time control, pressure and volume control, and systems to prevent overpressuring or inadvertent... 

ALIGN agitator pump drive motor in accordance with Vendor Manual VM-0093. 

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