GLYCOL REBOILER EMISSIONS CONTROL PROCESS TESTED

Aug. 23, 1993
A process that combines proven technologies for maximum control of air pollutants from glycol dehydrators has been developed and undergone a successful prototype field experiment. Radian Corp., Austin, developed the process under contract to the Gas Research Institute (GRI), Chicago, for control of volatile organic compounds (VOCs) including benzene, toluene, ethylbenzene, and xylene, commonly known as BTEX. The field experiment indicated that 98.4% of BTEX and other VOC emissions generated by

A process that combines proven technologies for maximum control of air pollutants from glycol dehydrators has been developed and undergone a successful prototype field experiment.

Radian Corp., Austin, developed the process under contract to the Gas Research Institute (GRI), Chicago, for control of volatile organic compounds (VOCs) including benzene, toluene, ethylbenzene, and xylene, commonly known as BTEX.

The field experiment indicated that 98.4% of BTEX and other VOC emissions generated by the unit were removed.

INDUSTRY CONCERN

GIN,col dehydrators remove water from natural gas to prevent hydrate formation and corrosion. During the absorption step, the glycol also removes some VOCs and BTEX. When the glycol is regenerated absorbed water is boiled off, along with the absorbed VOC, and released into the atmosphere.

Both Governmental regulators and the natural-gas producers have identified BTEX and other VOC emissions from glycol dehydrators as a significant air pollution problem.

With some 20,000 glycol dehydrators currently in use in the U.S., the potential cost of controlling these emissions could significantly affect the industry.

(Editor's note: An OGJ series has covered how operators of -glycol reboilers can analyze their units' emissions to determine the extent of VOC and BTEX content; OGJ, May 17, p. 28; MaN, 31, p. 61; and June 14, p. 36.)

SOUTH TEXAS SITE

The R-BTEX process prototype experiment was undertaken at a 35-MMcfd dehydrator in South Texas.

With no control, the dehydrator would release approximately 51 tons/year (tpy) of VOCs Controlled emissions are estimated to be only, 1.65 tpy, a level considerable lower than proposed by pending regulations.

The wastewater stream emitted from the process contains 2 ppm BTEX and other hydrocarbons. This concentration is substantially below, for example, the value required for direct discharge into Gulf of Mexico waters from offshore production platforms,

With the prototype process data, engineering studies indicate that the capital and operating costs of the unit are extremely competitive with other air emissions technologies.

GRI and Radian are now seeking host sites for a field test program. Installation and tests are scheduled to begin immediately.

Copyright 1993 Oil & Gas Journal. All Rights Reserved.