Wetting solids

In the case of emulsions with three liquids the presence of the third phase results in a reduction of the energy input for the emulsification process, whereas the emulsion with a Hquid crystal as the third phase shows interesting stabilization mechanisms. Finally, the emulsion with added particles illustrates the importance of Hquid—solid wetting for stabiHty. 

F. Brochard, J. Daillant. Drying of solids wetted by thin films. Can J Phys 62 1084-1088, 1990. 

In wet scrubbing the dust is removed by counter-current washing with a liquid, usually water, and the solids are removed as a slurry. The principal mechanism involved is the impact (impingement) of the dust particles and the water droplets. Particle sizes down to 0.5 /i.m can be removed in suitably designed scrubbers. In addition to removing solids, wet scrubbers can be used to simultaneously cool the gas and neutralise any corrosive constituents. 

When a drop of liquid is placed on a solid surface, it will displace the gas and spread over the surface. If the contact angle is <90°, the liquid wets the solid (wetting, Figure 18.1a) if the contact angle is >90°, the liquid does not wet the solid (nonwetting, Figure 18.1b). 

Plates of glass, PTFE, dolomite and marble were used. Dolomite and marble were chosen because they represent minerals found in oil reservoirs. Glass and PTFE were investigated because they represent high and low surface energy solids respectively and are good model systems for data comparisons. Liquid/solid wetting cycles were obtained for each of the solids in the liquids listed in Table III. 

Coalescence on a solid wetted preferentially by the organic phase... 

Liquid and solid interface (water drop resting on a solid, wetting, cleaning of surfaces, adhesion). 

Demulsifiers. A demulsifier is effective through four main actions (1) strong attraction to oil-water interface, (2) flocculation. (3) coalescence, ft) solids wetting. 

It is very rare that a single chemical structure will produce all the lour primary actions of a demulsifier, namely. (I) strong interface attraction. (2) flocculation. (3) coalescence, and (4) solids wetting. Generally two or more structures are blended to gethcr to produce a compound which gives the necessary combination ol actions. 

Flow nozzles are particularly suited for measurement of steam flow and other high-velocity fluids, fluids with some solids, wet gases, and similar materials. Because an exact contour is not critical, the flow nozzle can be expected to retain good calibration for a long time even under erosion or other hostile conditions. 

Hydrodynamic parameters that are required for trickle bed design and analysis include bed void fraction, phase holdups (gas, liquid, and solid), wetting efficiency (fraction of catalyst wetted by liquid), volumetric gas-liquid mass-transfer coefficient, liquid-solid mass-transfer coefficient (for the wetted part of the catalyst particle surface), gas-solid... 

Reaction-induced dispersion may be used as a substitute for conventional preparation methods for supported metal oxides (Wachs and Cai, 2001) it constitutes a particular case of solid—solid wetting, which is proposed to play an important role in catalyst preparation (Leyrer et al., 1990). Industrially relevant mixed metal oxide catalysts can be prepared by reaction-induced dispersion at temperatures that are significantly... 

The sol, which is a fluid mixture of water (sometimes containing organic solvent), catalyst and oligomerised silanes, turns into a solid, wet gel after some period of reaction time. The wet gel contains open channels, which are precursors to pores in the dried material. The resultant porosity of the dried gel is directly affected by the drying conditions, gel-solvent interfacial tension, and reactivity of... 

Disposing of solids wet with organic solvents alumina and anhydrous sodium sulfate... 

Wide chemical variation is possible within the intermediate types as well. The ethoxylated resin group demonstrates variable molecular weight on its resin base with different amounts and placement of ethoxylated groups. These structural variations provide a complete range of solubilities, charge neutralization tendencies, solids-wetting characteristics, and costs. 

To affix any definitive quality to any one type of intermediate is unrealistic, with the possible exception of the sulfonic acid salts, which exhibit fast water drop (rapid dehydration) and good solids wetting. However, because of the high dosages required, they are not usually cost-effective enough to be used in any major commercial emulsion-breaking process, with the exception of waste-oil treatment. 

Demulsifiers are very similar to emulsifiers because both are surfactant in nature. Consequently, the action of the demulsifier in emulsion breaking is to unlock the effect of the emulsifying agent(s) present. This unlocking is accomplished in three fundamental steps (2) flocculation, coalescence, and solids wetting. 

Solids Wetting. In most crude oil, solids such as iron sulfide, silt, clay, drilling mud solids, and paraffin complicate the demulsification process. Often such solids are the primary stabilizing material, and their removal is all that is necessary to achieve satisfactory treatment. To remove solids from the interface, they can either be dispersed in the oil or water-wetted and removed with the water. 

The given solid/liquid weight ratio of 3 10 in the reactors corresponds to 23 percent solids. This means that the reactor content is not a slurry but a packing of solids wetted to some extent, so that separation of the hydrolyzate from the residue must be effected... 

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