Solid-liquid, suspension pumping

Liquid-Solid Mixtures Liptak [Chem. Eng., 74(4), 151-158 (1967)] discusses a variety of techniques that can be used for the measurement of sohds-in-liquid suspensions or slurries. These include metering pumps, weigh tanks, magnetic flowmeter, ultrasonic flowmeter, gyroscope flowmeter, etc. 

While in batch operation, the fresh solution is fed into the crystallizer all at once the crystallization process carries on for a certain period, then the suspension is discharged from the crystallizer and is conveyed to the device for solid-liquid separation. For such operation the classifying leg (9), the overflow cofferdam (7), and the pump A are not needed. 

Generally, heat transfer, blending, and solids suspension are governed primarily by the impeller s pumping capacity and not by fluid shear rates. Solid-liquid mass transfer, liquid-liquid mass transfer, and gas-liquid mass transfer have certain requirements for fluid shear in addi-... 

Colloid Mill Colloid mills are rotor-stator systems that can be used to reduce the particle size distribution of both liquid dispersions (emulsions) and solid dispersions (suspensions). The emulsion or suspension is pumped through a narrow gap that is formed by the rotating inner cone and the stationary outer cone. The width of the annulus can be adjusted by changing the relative position of the two cones. The principal size reduction in colloid mills is due to the high shear forces that are caused by the velocity difference between the rotor and the stator surfaces. To increase wall friction and reduce slip, surfaces are usually not smooth but are roughened or toothed, which, in turn, changes the flow conditions from laminar to turbulent, thereby increasing the shear forces in the annulus. 

Stepanoff, A.J. (1964). Phunping solid-liquid mixture. Mechanical Engineering 86(9) 29-35. Stepanoff, A.J. (1965). Pumps and blowers Two-phase flow, ed. 2. Wiley New York. Stepanoff, A.J. (1970). Gravity flow of bulk solids and transportation of solids in suspension. Wiley New York. 

A specific design of the rotary vacuum drum filter is shown in Figure 3.14. The drum rotates at 10 to 60 revolutions per hour and a vacuum of approximately 400 to 160 torr is built up with a liquid seal pump that is connected to the drum cells via the control head and filtrate pipes. This sucks the liquid through the filter cloth, and the solids contained in the suspension are deposited in a uniform layer on the cloth on that part of the drum that is submerged in the feed suspension. 

To a vigorously stirred suspension of 2 mol of lithium amide in 2 1 of liquid atimonia (see II, Exp. 11) was added in 15 min 1 mol of propargyl alcohol (commercial product, distilled in a partial vacuum before use). Subsequently, 1 mol of butyl bromide was added dropwise in 75 min. After an additional 1.5 h, stirring was stopped and the ammonia was allovied to evaporate. To the solid residue were added 500 ml of ice-water. After the solid mass had dissolved, six extractions with diethyl ether were performed. The (unwashed) combined extracts were dried over magnesium sulfate and then concentrated in a water-pump vacuum. Distillation of the residue through a 40-cm Vigreux column afforded 2-heptyn-l-ol, b.p. 

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