Dehydration, natural gas

Breakdown of diethylene glycol use is as follows unsaturated polyester resins (20%), polyester polyols (15%), antifreeze blending (12%), triethylene and tetraethylene glycol (9%), solvents (9%) morpholine (7%), and natural gas dehydration (4%). Much of the market is captive. The merchant market is small. 

Membrane processes offer an alternative approach to natural gas dehydration and are being developed by a number of companies. Membranes with intrinsic selectivities for water from methane of more than 500 are easily obtained, but because of concentration polarization effects, actual selectivities are typically about 200. Two possible process designs are shown in Figure 8.33. In the first... 

Case SG Shell Global Solutions Natural Gas Dehydration (40). This case involves membrane separation for natural gas conditioning (dehydration). The mass of equipment is reduced by 70% (factor of 3 reduction) compared to the conventional process. From this we derived that the construction volume is reduced by the same factor, 3. The capital expenditure and operation cost reduction figures are given by Rijkens (40). 

Diethylene glycol is used in the manufacture of polyurethane resins, unsaturated polyester resins, antifreeze blending, triethylene glycol, morpholine, and natural gas dehydration. 

The glycol circulation rate for Case 1 is equivalent to 9.7 gal of TEG per lb of water removed and in Case 2 it is 5.9 USgal/lb. These are well in excess of the typical 2 to 4 USgal/lb typically recommended for a natural gas dehydration unit. Zabcik and Frazier (1984) do not offer an explanation as to why the glycol circulation rate is so high. 

Control GP [Aqualon]. TM for corrosion inhibitor and stabilizer for glycol natural-gas dehydrators. 

Tab. 7.1 shows the established applications in the field of membrane gas separation. One of the new and currently small appHcations shown in Tab. 7.1 is natural gas dehydration. Problems related to this separation wiU be discussed in the last part of this chapter (basic process design considerations). 

Figure 14.8 Membrane process flow schematics of a natural gas dehydration plant of PRISM...

As shown by Table 1, the only large-scale application of adsorbent aluminas prior to 1940 was as desiccants. Both air and natural gas dehydration were being routinely performed with waste-heat regeneration of the alumina columns. In later years, dehydration with aluminas was extended to cracked gas and heavier hydrocarbon streams, as well as those containing carbon dioxide and ammonia. 

Rijkens, H. and Sponselee, J. (2001). Membrane developments for natural gas dehydration. NPT Procestechnologie, No. 2, pp. 51-53, March-Apiil. 

Our company s natural gas dehydration station was located in a picturesque section of the desert just south of El Gringo, Texas. When I arrived there on a Saturday evening to consult on an excessive moisture problem in our gas shipments, I was surprised to find the station deserted, Unlike petroleum refineries, natural gas processing equipment is designed to operate unattended. 

We therefrom report on natural gas dehydration prompted by nucroemulsion extraction. To do this, phase diagrams were constructed, and compositions that favor the formation of water-in-oil microemulsion systems were selected, since it is interesting and even required that water be accommodated within the cores of reversed droplets in the self-assembled systems generated. 

Dantas Neto, A. A., Dantas, T. N. C., Barros Neto, E. L., and Ndbrega, G. A. S. 2004. Process of natural gas dehydration with microemulsion, Brazilian Patent PI0401240. 

Procedures, General Design Concept, Choice of Solvent, Selection of Column Diameter, Physical Absorption, Solvent Absorption, Natural Gas Dehydration, Gas Drying, Sulfuric Acid Manufacture, Formaldehyde Absorption, Absorption with Chemical Reaction, Cracked Gas Scrubbing, Amine Systems, Hot Carbonate Systems, Multicomponent Absorption, Reboiled Absorbers, Example Problem, Notation, References... 

Figure 11-6. Large glycol natural gas dehydration plant. Courtesy of Southern Counties Gas Co. of California...

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