Solids and pastes

A selection chart for solids mixing equipment is given by Jones (1985). 

Type of equipment Mixing action Applications Examples 

Rotating cone, double cone, drum Tumbling action Blending dry, free-flowing powders, granules, crystals Pharmaceuticals, food, chemicals 

Air blast fluidisation Air blast lifts and mixes particles Dry powders and granules Milk powder detergents, chemicals 

Horizontal trough mixer, with ribbon blades, paddles or beaters Rotating element produces contra-flow movement of materials Dry and moist powders Chemicals, food, pigments, tablet granulation 

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Economics, As with the alkyltin stabilizers, the market pricing of the mixed metal stabilizers tend to be directed by the particular application. The calcium—zinc and barium—cadmium packages are typically used at 2.0—4.0 parts per hundred of PVC resin (phr) in the formulation. These completely formulated products are sold for 2.50— 4.40/kg for the liquid products and 3.20— 6.50/kg for the solids and pastes. The higher efficiency products aimed at rigid applications tend toward the higher end of the cost range. 

There are more than 100 commercially available organic peroxides in well over 300 formulations, e.g., neat liquids and solids, and pastes, powders, solutions, dispersions, and emulsions, that have utility in many commercial applications. 

Foam inhibition is evaluated by the following procedure a definite quantity of the antifoam is added (usually - 0.1 cm3) to the foaming solution (100 cm3). Solid and paste-like antifoams are introduced as solutions. The time needed to fill up the foam vessel as well as the average foam lifetime with Tm and xam, respectively, with and without antifoams, are measured. It is convenient to express the foam inhibition ability either as the relative stability Tre[ (Eq. (9.2)) or as the defoaming coefficient [16]... 

A great variety of specialized equipment has been developed for mixing dry solids and pastes (wet solids). The principal types of equipment and their fields of application are... 

Typical dryers for solids and pastes include tray and screen-conveyor dryers for materials that cannot be agitated and tower, rotary, screw-conveyor, fluid-bed, and flash dryers where agitation is permissible. In the following treatment these... 

Mixing is harder to define and evaluate with solids and pastes than it is with liquids. Quantitative measures of mixing are discussed later in this chapter, measures that aid in evaluating mixer performance, but in actual practice the proof of a mixer is in the properties of the mixed material it produces. A well-mixed product is one that does what is required and has the necessary property—visual uniformity, high strength, uniform burning rate, or other desired characteristic. A good mixer is one that produces this well-mixed product at the lowest overall cost. 

There is a regulation on using burned ash of municipal wastes as construction materials for roads. The standard value is determined about Hg, Cd, Pb, Cr, Cu, Zn, Ni, Cl, SO4, CN, conductivity and pH. The elution test method is regulated by the DIN 38414. This method is applied to solid- and paste-like wastes or slime. We add 100 g of samples of which size is adjusted to less than 10 mm into distilled water of 1 1. The solution is mixed for 24 h using a rotary agitation device. After filtrating it by a membrane filter with a pore size of 0.45 pm, the concentrations of metals, conductivity, and pH will be measured. 

Characteristics discrete k, reference measurements, at-line/on-line for solids and pastes, robust, low cost, user s friendly, long life). 

Uses Detergent, foam stabilizer, thickener, refatting agent for toiletries, solid and paste end prods. emulsion stabilizer Features Improved washing power... 

Yosypchuk B, Barek J (2009) Analytical applications of solid and paste amalgam electrodes. Crit Rev Anal Chem 39 189 203... 

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