Emulsion breaking continuous

Figure 17. Continuous emulsion breaking emulsion flow rate 20 1/h. I...first breaking step, II...second breaking step.

In contrast to the mentioned usual methods, the electrical emulsion breaking works at room temperature, has no moving parts, low energy input (only low condensator current between the electrodes because of low conductivity organic bulk phase), and it is possible to separate small droplets from the continuous phase. 

Effect of Continuous Phase Composition. With increasing concentration of Shellsol T in the continuous phase and therefore decreasing bulk phase viscosity (as shown in Figure 13), the emulsion breaking efficiency increases (Figure 14). As expected, the mutual approach of the water droplets will be facilitated in lower viscous continuous phases. 

Figure 14. Effect of continuous phase composition on emulsion breaking efficiency.

The ability of an oil to remain liquid during refrigerator storage is determined by the cold test analysis crystallization resistance is measured as the time in hours before the oil appears cloudy at 32°F (CPC). Standardized AOCS Method Cc 11-53 requires that dry filtered oil be placed in a sealed 4-ounce bottle and submerged in an ice bath. A go-no-go examination for clarity after 5 hours is stipulated by the Official AOCS Method however, most laboratories practice the alternative procedure which continues the clarity examination until a cloud appears. The cold test procedure was developed to evaluate cottonseed oil for the production of mayonnaise and salad dressings. Oil that solidifies at refrigerator temperatures will cause an emulsion-break with a resultant separation of the oil and water phases. Currently, the cold test is also utilized to ensure that bottled oils for retail sale will not develop an unattractive appearance on the grocery shelf. 

Emulsion Stability. An emulsion is defined as a macroscopic dispersion of two liquids, one of which forms the continuous phase of the system and the other forms the discrete phase. An emulsion of two liquids without a stabilizer will quickly break into two liquid layers. Emulsions destabilize by three distinct processes breaking, creaming, and flocculation (Figure 14). When emulsions break, the initial small droplets of the emulsion spontaneously join to form larger droplets. This process is termed coalescence , and it ultimately leads to two separate liquid layers. 

It was found that the formation brine could not be completely eliminated from the heavy crude oil. Because of some limitations in the emulsion-breaking process, about 1% of this concentrated brine remained in the oil as a W/O emulsion. The brine droplets that were of very small size, typieally less than 2 pm, did not join the water continuous phase during preparation of the commercial emulsion, but remained as droplets encapsulated inside the oil drops. It is also possible that the proximity of the A /B" transition region could have promoted the formation of a multiple... 

The stirring/mixing continues until the emulsion breaks. An emulsion breaking is considered to occur when the bituminous emulsion and filler mixture becomes pasty and forms lumps, which do not adhere to the walls of the pan. This, combined with a noticeable increase in stirring power, indicates the end of mixability. 

A simplified flow sheet for the LEM continuous circuit that was used in the field tests is shown in Figure 1. The technique used four main unit operations (emulsion generation, copper extraction, emulsion breaking, and metal recoveiy). 

Oiling out Continued coalescence of lipid emulsion particles, resulting in irreversible separation of the emulsion (or breaking of the emulsion). 

For separation of colloidal particles and for breaking down emulsions, the ultra-centrifuge is used. This operates at speeds up to 30 rpm (1600 Hz) and produces a force of 100,000 times the force of gravity for a continuous liquid flow machine, and as high as 500,000 times for gas phase separation, although these machines are very small. The bowl is usually driven by means of a small air turbine. The ultra-centrifuge is often run either at low pressures or in an atmosphere of hydrogen in order to reduce frictional losses, and a fivefold increase in the maximum speed can be attained by this means. 

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