Hydrocarbon skimming

Four skimming connections with trycocks are normally provided at the outlet end of the drum, at the normal liquid level, and at 150 mm, 450 mm, and 500 mm below the normal level. Liquid hydrocarbon skimmed from these connections can be pumped to a suitable slop system. A coimection to the suction of a blowdown drum pumpout pump, if available, is adequate for this purpose. 

To prevent this situation from developing, hydrocarbon skimming taps should be provided in the bottom of natural gas amine H2S scrubbing towers. 

Liquid hydrocarbon skimming unities in the absorber sump, the rich amine flash drum, the regenerator sump, and the amine regenerator overhead accumulator (Bacon, 1987). 

In the initial black Hquor concentration, saponified fatty and resin acid salts separate as tall oil soaps (see Tall oil). These soaps can be skimmed from the aqueous spent Hquor, acidified, and refined to give a cmde tall oil composed of resin acids, chiefly abietic and neoabietic fatty acids, chiefly oleic and Hnoleic and an unsaponifiable fraction made of phytosterols, alcohols, and hydrocarbons. Tall oil is fractionated primarily into fatty acids (see... 

Even though some oil may be removed through skimming connections (if provided), condensed hydrocarbon is discharged with the effluent water, often in the form of an emulsion, which may result in pollution, toxicity or separator... 

The chemistry of a third group of conversion techniques -i.e., partial conversion methods which skim hydrocarbon gases and/or liquids from the coal and leave a char suitable for use as a boiler fuel or gasification feedstock - is. If anything, even more speculative than the chemistry of liquefaction. 

The PetroTrap , a passive skimming system, is a long and narrow cylindrical device that uses an active buoy/filter system to remove free-floating hydrocarbon product from a well and store it in a collection cannister. The unit uses no electricity and can be installed quickly. According to the vendor, the PetroTrap is applicable for the recovery of most refined fuels. 

In Fig. 1 oil is skimmed only by the top pipe of a parallel double pipe skim system. In this design both the interceptor bay and oil sump are covered by floating slabs of epoxy-coaled polyurethane foam to reduce oil evaporation and hydrocarbon odors. 

With automatic oil skimming and a relatively small area involved, the CPI is much easier to cover and thus retains hydrocarbon vapors. 

Oil agglomeration treatment of a suspension of fine coal particles suspended in water with a light hydrocarbon oil so that the particles are preferentially collected by the oil, which separates as a floating pasty agglomerate and can be removed by skimming. Developed as a method for recovering fine coal particles by Trent in 1914. 

These are for the direct determination of fat in various products. They are all modifications of the Babcock method for fat in milk. They are designed so that if a measured volume of sample is placed in the tube and then centrifuged, the percent fat can be read directly on the stem. These are from left to right, skim milk, (0.5% in 0.01 increments), milk (8 % in 0.1 increments), ice cream (20% in 0.2 increments), cream (30 or 50% in 0.5 increments), and cheese (20% in 0.2 or 50% in 0.5 increments). Unsaturated hydrocarbons in gasoline can be handled in a similar manner, as can essential oils in extracts. 

The application of the quasi-cw, ultraviolet laser source to kinetic studies was demonstrated in the laser photolysis/laser-induced fluorescence experiments shown schematically in Figure 2. Chemical reactions were initiated by 193-nm photolysis of N2O in N20/H20/hydrocarbon/helium gas mixtures. The 0( D) atoms formed by photodissociation rapidly converted to OH through reaction with H2O, and time-resolved OH concentrations were measured as functions of hydrocarbon number density by laser-induced fluorescence. Hydroxyl radical fluorescence was excited by pumping the nearly coincident Pjl, Qi3, and Qi3 (0,0) band transitions at 308.16 nm, (15) and radiation emanating from the reaction volume in a downward direction was skimmed by black-anodized collimators, focused by quartz lenses, selected by a bandpass filter (308.3 nm peak, 8 nm FWHM), and detected by an RCA 8850 photomultiplier operating in the photon-counting mode. 

Addition of small quantities of hydrocarbon oils to raw coal pulps causes preferential wetting of the coal by oil, tending to increase the surface tension forces operating at the coal/water interface. If air is admitted to the system, bubbles attach preferentially to the oil-wet coal surfaces thereby increasing the buoyancy of the coal particles, hence causing rapid separation from the heavier, unoiled mineral particles. The coal is collected as froth on the surface of the system and recovered by skimming. 

Among the first satirrated zone treatment and containment methods applied for LNAPL contaminants (i.e., lighter than aqueous phase liqitids) were interceptor trenches that penetrated the upper portion of the near source saturated zone. In these cases, the trench provides a collection point for hydrocarbon contaminants by skim-... 

If naphtha is accumulating in the regenerator reflux drum, excessive concentrations of propane and butane will occur in sulfur plant feed. A commercially proven method to eliminate this problem is detailed in Figure 4-7. The rich amine surge drum is retrofitted with baffles. Figure 4-7 is roughly drawn to scale. This baffle arrangement will automatically skim off the hydrocarbons. 

An abnormality had been reported on the 30th day. A quantity of light hydrocarbon was skimmed off the amine regenerator reflux drum. When a sample of this hydrocarbon was drawn, it bubbled in the sample... 

Primary treatment uses a settling pond to allow most hydrocarbons and suspended solids to separate from the wastewater. The solids drift to the bottom of the pond, hydrocarbons are skimmed off the top, and oily sludge is removed. Difficult oil-in-water emulsions are heated to expedite separation. 

In units treating sour hydrocarbon gases at high pressure, it is customary to flash the rich solution in a flash drum maintained at an intermediate pressure to remove dissolved and entrained hydtocaibons before add gas stripping (see Chapter 3). When heavy hydrocarbons condense frmn die gas stream in the absorber, die flash drum may be used to skim off liquid hydrocarbons as well as to remove dissolved gases. The flashed gas is often used locally as friel. A small packed tows with a lean amine wash may be installed on top of the flash drum to remove HjS from die flashed gas if sweet fuel gas is required (Manning and Thompson, 1991). 

It is possible to remove small particles using dispersed or dissolved gas flotation devices. These units are primarily used for removing suspended hydrocarbons from water. Gas is normally dispersed into the water or released from a solution in the water, forming bubbles approximately 30-120 pm in diameter. The bubbles form on the surfaces of the suspended particles, creating particles whose average density is less than that of water. These rise to the surface and are mechanically skimmed. In the feed stream, chemicals called "float aids" are normally added to the flotation unit to aid in coagulation of solids and attachment of gas bubbles to the solids. The optimum concentration and chemical formulation of float aids are normally determined from batch tests in small-scale plastic flotation models on-site. Because of the difficulty of predicting particle removal efficiency with this method, it is not normally used to remove solids from water in production facilities. 

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