Natural glycol scrubbing

Glycol dehydrators are used to scrub water from natural gas to meet pipeline specifications but also pose a potential hazard to membrane systems. An upset in dehydrator operations can flood manbrane modules with triethylene glycol (TEG), commonly employed as the working fluid. 

Natural gas transported through common carrier pipelines must meet a moisture specification of 7 Ib/MMscf of water. Gas is usually dried to meet this requirement by scrubbing with a concentrated glycol solution. Figure 24—1 shows a standard glycol contactor tower, generator, and pump. 

Usually, natural gas treatment on the basis of thermal process engineering takes place in three steps (see Fig. 7.9). The first step that may consist of partial steps just like all other subsequent steps, serves the preparation of the crude gas for its processing. Here, for example, acid-forming gas components, such CO2, H2S and other sulphuric compounds are removed. Usually, chemical scrubbing with amines (MEA, DEA, MDEA) is applied in which the adsorbent is being regenerated. Then the natural gas is dried. In case of moderate water dew point requirements, glycol is used as wash liquor. The lowest water contents (< 1 ppm) are achieved with the application of zeolitic molecular sieves. Finally, mercury is removed in case aluminium will be used as material of construction for equipment. Mercury in contact with aluminium may lead to catastrophic corrosion. 

Uses Vise, builder for shampoos thick, copious, stable foam useful in shampoos, facial scrubs, bubble baths, hand soaps, and detergent compositions Properties Yei. Iiq. when fresh (cryst. on aging) mild, fruity odor sol. in alcohols, glycols, glycol ethers, polyols, aliphatic (lower members), aromatic, and chlorinated hydrocarbons, and natural fats disp. in water and min. oil sp.gr. 0.96 0.01 dens. 8.0 Ib/gal vise. 2500cps min. (10% disp.) flash pt. (OC) > 170C acid no. 1.0 max. pH 10.2 0.5 (10% disp.) 100% active 88% min. amide content Schercomid SLM [Lubrizoi Advanced Materials]... 

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