Dehydration of Acid Gas Prior to Injection

摘要

Acid gas is a mixture of hydrogen sulfide and carbon dioxide, with small amounts of other components, and usually saturated with water, which is the by-product of the sweetening of sour gas. Acid gas injection is an environmentally friendly and economically viable option for dealing with unwanted acid gas and in particular small quantities of acid gas. Basically acid gas injection involves the compression of the gas to a sufficient pressure, transport of the compressed gas and injection into a disposal well. In many injection schemes the gas does not require dehydration beyond that achievable by compression and cooling alone. In some circumstances additional dehydration is required. There are a number of methods commonly used to dehydrate the acid gas. The most popular is absorption of water with triethylene glycol (TEG). This paper discusses the design considerations for application of both methods of dehydrating acid gas: by compression and cooling alone, and by TEG.