Water-hydrocarbon separators

The neutralized cleavage product, consisting of acetone, phenol, water, hydrocarbons, and trace organic impurities, is separated in a series of distillation columns. Also in this section alpha-methylstyrene is either recovered as a product or hydrogenated to cumene. 

A vessel handling large amounts of liquid or a large liquid surge volume will usually be horizontal. Also, where water must be separated from hydrocarbon liquid, the vessel will be horizontal. A vessel with small surge volume such as a compressor knockout drum will usually be vertical. 

The gas and liquid are separated in the cold separator, which is a three-phase separator. Water and glycol come off the bottom, hydrocarbon liquids are routed to the distillation tower and gas flows out the top. If it is desirable to recover ethane, this still is called a de-methanizer. If only propane and heavier components are to be recovered it is called a de-etha-nizer. Tiie gas is called plant residue and is the outlet gas from the plant. 

Many processes require the separation of immiscible liquid/liquid streams that is, water/hydrocarbon. The setding unit must be of sufficient height (diameter) and length to prev ent entrainment of the aqueous phase into the hydrocarbon and vice versa. Horizontal units are usually best for setding and possibly vented units for decanta-don (but not always). 

The basic refining tool is the common distillation unit. It is usually the first process in refining crude oils. Crude oil normally begins to vaporize at a temperature somewhat less than what is required to boil water. Hydrocarbons with the lowest molecular weight vaporize at the lowest temperatures, whereas successively higher temperatures are applied to separate or distill the larger molecules. 

Calcium aluminate chloride, phase in Portland cement clinker, 5 472t Calcium aluminate fluoride, phase in Portland cement clinker, 5 472t Calcium aluminoferrite, phase in Portland cement clinker, 5 472t Calcium aluminoferrite hydrate, 5 477t Calcium—aluminum alloys, 4 530 Calcium amalgam, 22 773 Calcium ammonium nitrate, 2 724 Calcium analysis, of water, 26 37 Calcium A zeolite, separation of hydrocarbons by, 16 823 Calcium—barium—silicon alloy, 22 519 Calcium-bearing manganese silicon,... 

The toxicity and volume of some deoiled and dewatered sludge can be reduced further through thermal treatment. Thermal sludge treatment units use heat to vaporize the water and volatile components in the feed and leave behind a dry solid residne. The vapors are condensed for separation into hydrocarbon and water components. Noncondensable vapors are either flared or sent to the refinery amine nnit for treatment and nse as refinery fnel gas. 

Thietane oxides serve as selective solvents for the separation of hydrocarbons. The extracting power of a mixture of water and thietane 1-oxide is considerably greater than that of dimethyl sulfoxide. ... 

The QED Environmental Systems Ferret in-well separator removes hydrocarbons from ground-water. QED Environmental Systems, Inc., has regional distributors of its Ferret in-well separator from whom the product is commercially available. 

Separate water from reflux when distilling hydrocarbons... 

Point Q2 is a quadruple point. At Q2, four phases are in equilibrium liquid water, hydrocarbon liquid, hydrocarbon gas, and solid hydrate. The almost vertical line extending from point Q2 separates the area of liquid water and hydrocarbon liquid from the area of liquid water and hydrate. 

WATER-AIR EQUILIBRATION. McAuliffe (6) introduced a multiple phase equilibrium procedure for the qualitative separation of hydrocarbons from water-soluble organic compounds. For n-alkanes, more than 99% were found to partition in the gas phase after two equilibrations with equal volumes of gas and aqueous solution. Cycloalkanes require three equilibrations to be essentially completely removed, and oxygen-containing organic compounds (e.g., alcohols, aldehydes, ketones, and acids) remain in the aqueous layer. Thus, after equilibration with equal volumes of gas, an immediate clue is given regarding the identification of the compound. More details of this technique can be found in Chapter 7. 

Figure 183. Drums with coalescers for assisting in the separation of small amounts of entrained liquid, (a) A liquid-liquid separating drum equipped with a coalescer for the removal of small amounts of dispersed phase. In water-hydrocarbon systems, the pot may be designed for 0.5 ft/sec (Facet Enterprises, Industrial Division), (b) An oil-water separator with corrugated plate coalescers (General Electric Co.).

Analytical Properties Has been used to separate aromatic hydrocarbons, heterocyclic compounds, phenols, and aryl amines using methanol/water/phosphate buffer extent of adsorption affects retention times also used as a mobile phase modifier to provide a dynamically modified silica Reference 51-57... 

Mixed Solvents Effect. Using mixed solvents can improve selectivity. For example, adding small amounts of water has improved the selectivity of furfural in separating C4 hydrocarbons (24). Baumgarten and Gerster (25) have studied how various solvents affect the selectivity of furfural for the pentane-pentene pair. They concluded that for only a few solvents some improvement was observed. The resulting selectivity lies between the selectivity of the pure solvents (see Table III). To avoid immiscibility at high solvent concentrations, a second solvent is sometimes added (25). 

Table I shows that, as the boiling point of the hydrocarbon used as the entrainer increases so does that of the azeotrope with water and the percent of water therein. A high percentage of water in the azeotrope is desired for the heat required for the distillation, which is mainly that of the latent heat of the water plus that of the entrainer. Sufficient entrainer should be available in the azeotrope for reflux to the column although this requirement is not large. Also, the solubility or dilution effect is better with lower-boiling hydrocarbons. Thus there are several factors to be balanced in choosing the azeotrope. The effect of relative boiling points, vapor pressures, and amounts of different entrainers in their azeotropes with water has been discussed as affecting the choice of entrainers for separating water from acetic acid (5). However, that represents a much more difficult selection because there the quantity of reflux is important and also the solvent characteristics of the entrainer for the acetic acid also control the choice.

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