Centrifugation types

Shipping. Bulk milk is hauled to the processing plant in insulated tanks using tmck tanks or trader tankers. The milk is transferred from the bulk tank to the tanker with a positive or centrifugal-type pump. For routes of some distance, pick-up every other day reduces handling costs. 

Reverse Osmosis. Membranes are used for the separation of smaller components (<500 daltons). They have smaller pore space and are tighter than those used for ultrafiltration. High pressure pumps, usually of the positive piston or multistage centrifugal type, provide pressures up to 4.14 MPa (600 psi). 

In a centrifuge technique, various centrifuge types are used for sludge thickening. 

Method of separation Rotor type Centrifuge type Manner of liquid discharge Manner of solids discharge or removal Centrifuge speed for solids discharge Capacity ... 

An interlock is provided through a centrifugal type of pressure switch (PS) to trip the engine in the case of low lube (lubricating) oil pressure during a run. Since during a. start oil pre.s.sure has not built up, a timer, 7 j is introduced to bypass the trip interlock and avoid a false trip. A relay (contactor), d], is used to provide lube oil pressure interlock. 

Air compressor (axial or centrifugal type) without or with adjustable guide vanes (8) and guide vane setting 19... 

Milk-of-lime transfer pumps should be of the open impeller centrifugal type. Pumps having an iron body and impeller with bronze trim are suitable for this purpose. Rubber-lined pumps with rubber-covered impellers are also frequently used. Makeup tanks are usually provided ahead of centrifugal pumps to ensure a flooded suction at all times. Plating out of lime is minimized by the use of soft water in the makeup tank and slurry recirculation. Turbine pumps and eductors should be avoided in transferring milk of lime because of scaling problems. 

Pumps may be classified as reciprocating, rotary, or centrifugal. The first two are referred to as positive-displacement pumps because, unlike the centrifugal type, the liquid or semiliquid flow is broken into small portions as it passes through the pump. 

Figure 4-28. Wall-wiping centrifugal type separator. Courtesy of Wright-Austin Co.

For most general-service noncorrosive applications, the wheels use medium- to heavy-gauge carbon or alloy steel. For the centrifugal types, a die-formed entrance shroud provides smooth entrance flow of the air into the wheel. A solid steel plate serves as a back plate of the single entrance wheel, but of course, cannot be used on a double-entry wheel. Flere, both sides of the wheel have entrance shrouds. Figure 12-120C. 

A fan in which the air path through the impeller is intermediate between the axial and centrifugal types giving the benefit of increased pressures but capable of being con-stmcted to provide either axial or radial discharge. Static efficiency is typically 70-75 per cent. 

Figure 46.5 Centrifugal types of fan. (a) Centrifugal (b) paddle or radial bladed (c) forward curve (d) backward curve...

The main refrigerant for packaged water chillers of the centrifugal type are R123 and R134a. 

The circulation pump should be a centrifugal type with a plastic or PVC impellor, or cast iron with adequate corrosion inhibitor. The acid tank, hoses, and other equipment should be connected to and from the boiler using suitable connection points. This usually is the bottom BD connection (with the valve removed) and the open manhole as the top point. 

For onshore facilities, water may be supplied from local public water mains, storage tanks, lakes and rivers. In these cases a conventional horizontal pump is used. The preferred design for onshore fire water pumps is a horizontal centrifugal type with a relatively flat performance curve (i.e., pressure versus quantity). The discharge pressure is determined by the minimum residual pressure required at the most remote location of the facility flowing its highest practical demand with allowances added for piping friction losses. 

Some design concepts for generating uniform droplets have been proposed by Lee et al.[88] These include (a) centrifugal type chamber, (b) atomization by two opposing air-liquid jets, and (c) spinning disk coupled with an ultrasonic field. Some other conceptions include (d) rocket nozzle chamber, (e) frozen particles, (f) rotating brush, and (g) periodic vibrations using saw-tooth waves, etc. 

In an attempt to obtain the benefits of repeated spray formations, a centrifugal type absorber has been developed from the ideas of Piazza for a still head. The principle of the unit is shown in Figure 12.31. A set of stationary concentric rings intermeshes with a second set of rings attached to a rotating plate. Liquid fed to the centre of the plate... 

Cell Line Product Reactor Volume (L) Max. Perfusion Rate (d ) Cultivation Time (d) Centrifuge Type g-factor " Feed Flow Rate " (L min ) Max. Viable Cell Cone. (10 mL- ) Separation Efficiency (%) Reference... 

Mineral sulfides have significantly different densities from those of coal, so they can be removed from it by methods that take advantage of this difference, such as hydrocycloning, dry cycloning, and froth flotation. In hydrocycloning, for example, a slurry of coal and water is introduced into a centrifuge-type tank with a central... 

Short Term Tests. Centrifuge Tests. Samples of the slurries are syringed into tubes which are capped at both ends. The tubes are then centrifuged (International Centrifuge Type SB) at a force of 50 g for 30 minutes. After the acceleration, samples from the top and bottom of... 

Centrifugal type, sample stage nonoverloading, long coupled end-suction... 

Forced circulation reboilers may be either horizontal or vertical. Since the feed liquid is at its bubblepoint, adequate NPSH must be assured for the pump if it is a centrifugal type. Linear velocities in the tubes of 15-20 ft/sec usually are adequate. The main disadvantages are the costs of pump and power, and possibly severe maintenance. This mode of operation is a last resort with viscous or fouling materials, or when the fraction vaporized must be kept low. 

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