Pumping fluids containing

Various coupling designs are available to transmit torque from the driver, eg, electric motor, to a pump. In order to contain the pumped fluid inside the pump and prevent the pumpage from leaking, several types of sealing methods are used. A few options are described herein. 

Eermanent magnets for both the internal and external rotors, there is ss heat to the pumped fluid than with canned-motor pumps. Some canned-motor pumps have fully pressure-rated outer shells, which enclose the canned motor others don t. With magnetic-drive pumps, containment of leakage through the can to the outer shell can be a... 

In the Sundyne Canned Motor design, the entire outside of the motor is enclosed in a secondary leakage containment shell or can. Primary leakage protection is provided by corrosion resistant liners which are seal welded and 100% leak checked to assure that pumped fluid does not contact the stator windings or rotor core. There is no shaft protrusion to seal and thus no seals to leak. 

The bladder pump is similar in concept, with a flexible membrane bladder attached to the air line inside the chamber. A bladder prevents operating air from contacting pumped fluids therefore, when air is released to the atmosphere it does not contain vapors. 

Included in the class of fluid-entrainment pumps are not only pumps that use a fast-streaming vapor as the pump fluid, but also liquid jet pumps. The simplest and cheapest vacuum pumps are water jet pumps. As in a vapor pump (see Fig. 2.46 or 2.51), the liquid stream is first released from a nozzle and then, because of turbulence, mixes with the pumped gas in the mixing chamber. Finally, the movement of the water - gas mixture is slowed down in a Venturi tube. The ultimate total pressure in a container that is pumped by a water jet pump is determined by the vapor pressure of the water and, for example, at a water temperature of 15 °C amounts te about 17 mbar. 

The sample, air, and saline are mixed and pumped through the dialyzer and then discarded. The recipient fluid contains the diacetyl monoxime reagent properly segmented with air. After exiting from the dialyzer, concentrated sulfuric acid containing arsenic pentoxide is added to the recipient stream, mixed, and passed through the heating bath. The color developed is then read at 480 mp in a 6-mm cell and recorded in the usual manner. 

Many substances can be transported into the cell (and vice versa) against a concentration gradient. This is an active transport process, and it requires energy in the form of ATR It is to be distinguished from a passive transport process, which is simple diffusion across membranes. One of the better understood systems of this type is the sodium-potassium ATPase (or Na/K) pump, which maintains high potassium and low sodium levels in the cell. These are up to 160 meq/L for K+ and about 10 meq/L of Na+ inside the cell. Extracellular fluid contains about 145 meq/L of Na+ and 4 meq/L of K+. The simultaneous movement of one substance out of the cell and another into the cell is an antiport. A substantial percentage of the basal metabolic rate (see Chapter 21) is accounted for by the activity of the Na/K pump. ATPase (Na/K pump) is lo-... 

Fig 19b Semi-open impeller for handling fluids containing pulpy solids (courtesy of Nagle Pumps)... 

No priming is required with rotary positive pumps, and they are well adapted for pumping highly viscous fluids. A constant rate of delivery is obtained, and the fluid may be delivered at high pressures. Because of the small clearance that must be maintained, this type of pump should not be used with nonlubricating fluids or with fluids containing solid particles. 

Seals for pumps are generally mechanical. If the fluid contains salt crystals, which are abrasive, it is recommended that water be used to flush the seal. Both seal faces on the pump side should be of a hard material using carbon for one of the seal faces has not proven to be successful. The reader is again urged to contact seal manufacturers for their recommendation. 

Humans and other organisms are filled with complex fluids. Blood is a suspension containing around 40% by volume blood cells, which are flexible puckered disks roughly 10 / m in diameter, suspended in clear plasma, which is itself a viscoelastic fluid containing interacting macromolecules. The viscoelastic properties of blood determine the pumping load... 

In this type of CrDDS, the drug reservoir, which is a solution formulation, is contained inside the infusion compartment. It is physically separated from the pumping compartment by a freely movable partition (Fig. 21). The pumping compartment contains a vaporizable fluid, such as fluorocarbon, which vaporizes at body temperature and creates a vapor pressure. Under the vapor pressure created, the partition moves upward and forces the drug solution in the infusion compartment to be delivered, through a series of flow regulator and delivery cannula, into the blood circulation at a constant flow rate. The process is defined by ... 

In the feed section, the mainly l--hexene reactant (98.60% 1-hexene, 0.95% cis-3 hexene, 0.25% trans-2 hexene and 0.15% cis-2 hexene, supplied by Ethyl corporation) is introduced from an Instrumentation Specialties Company (ISCO) model 314 metering pump into a flowing stream of liquefied COo. The l-hexene/C02 mixture is then fed to a high pressure positive displacement pump contained in the SCESS. In this pump, fluids can be pressurized up to 6,000 psig and total flow rate can be adjusted between 46 ml/hr and 460 ml/hr. Since feed to the pump must be in a liquid state, both the l-hexene/C02 mixture and the pump head are sufficiently cooled by circulating chilled water at 5 C. The system pressure is controlled by means of an adjustable back pressure regulator. 

Containment seal chamber drain for condensing leakage. This plan is used when pumped fluid condenses at temperatures. System is supplied by manufacturer. 

Wang et al. (2004a) reported that excessive eccentric sucker-rod wear with beam pumps occurred when the produced fluid contained more than 100 mg/L polymer. The service life of rods was approximately only half a year, a 75% reduction compared to the rod life in waterflooding (waterflood producers with beam pumps had a service life of approximately 2 years). Wang et al. (2004c) also reported that based on the statistical data in the year 2000, 880 wells had been eccentrically worn in 2,365 rod-pumped wells, producing fluids containing polymer. Compared to the wells with no polymer before the year 1997, the number of wells with eccentric wear had increased by 840. Thirty-six percent of wells suffered the eccentric wear. The pump service work wells had also increased from 3.2% in 1997 to 27.1% in 2000 because of eccentric wear in rod-pumped wells. The main cause of eccentric wear on sucker rods was the normal stress of polymer solution, as explained next. 

Diffusion pumps employed in high vacuum pumping stations should contain pumping fluids that are relatively inexpensive and are oxidatively and chemically inert. They must be capable of attaining ultimate vacuums of 10-6 - 10-7 torr and should have the highest pumping speeds that are economically practical. 

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