Date of Award

5-1999

Document Type

Thesis

Degree Name

Master of Science (MS)

Department

Environmental Science

First Advisor

Essam Abdul Hafiz

Second Advisor

Dr. Mahmoud Fathy Abd-Rabbo

Third Advisor

Dr. Reyadh AI Mehaideb

Abstract

Gas industries in the United Arab Emirates are vastly growing in order to mainly cope with the increasing demand for energy productions as well as for the wise utilization of gas associate with the crude oil. Environmental problems coupled with gas employment necessitates the development of a management techniques that can lead to better control of emissions from gas processing companies since some of these emissions are unavoidable for safety reasons.

This study suggests a framework to be used to control emissions from Abu Dhabi Gas Liquefaction Company (ADGAS) in Das Island, which represents a typical major gas processing company in the region, through investigations of the impact of introducing a modification scheme, within the unit processes, on the quality of the surrounding atmosphere.

A baseline study for current emissions and ground level concentrations of four pollutants (sulphur dioxide, nitrogen oxides, carbon monoxide and particulates) was established. A computer model was then used to simulate the proposed modifications in order to reduce ground level concentrations that exceed regulatory standards.

Two main approaches were considered to minimize ground level concentrations. First, reducing flow of gas into the flares by adding compressors to recover any excess gas from going into the flares during operations. Second, upgrading sulphur recovery units to a higher efficiency and some other reduction can also be accomplished through sweetening of fuel gas directed to utilities.

The study concluded that the rates of emitted gas at ADGAS Liquefied Natural Gas Plant are exceeding the exposure limits under all emergency and current normal operation conditions. Gas turbines and boilers were proved to be the major sources for nitrogen oxides and carbon monoxide, while both sulphur recovery units and gas turbines are contributing to the emission of sulphur dioxide. In the meantime, upgrading of the sulphur recovery units to 97.5% resulted in 30% decrease in sulphur dioxide concentration. A significant decrease in nitrogen oxides and carbon monoxide as well as particulate concentrations resulted from adding a third boil-off-gas compressor.

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