Producing And Processing Sour Gas In The 1990s
Authors: Hyne J.B. 
Published: March 2010

Introduction

Western Canada has a long successful record of sour natural gas production dating back to the early 1950s. Under the watchful eye of Alberta's provincial regulatory agency, the Oil and Gas Conservation Board and its successor, the Energy Resources Conservation Board (ERCB), many innovative techniques have been developed by the Canadian gas processing industry that both optimize production and recovery and protect the environment from unnecessary impact. What can we predict from this experience about technological developments in sour gas production in the 1990s?

Technological development is driven by a combination of the needs or society and the inventiveness of its members. New developments in sour gas technology in the 1990s will be governed by these driving forces in no less important a manner than any other field.

Historically the major societal need that has driven sour gas technology has been the need for the hydrocarbon component, primarily the methane gas. The "sour ", hydrogen sulphide has been, until more recently, viewed as a nuisance or worse. There is little doubt that the need for gaseous hydrocarbons both as fuels and petrochemical building blocks will continue to be an important factor in driving technological developments in the sour gas business, making resources available from reservoirs that were previously inaccessible or uneconomic. The days of the simple equation when market demand for the hydrocarbon was the overriding factor in pushing technology to produce more sour gas are gone. The equation is now much more complex and that complexity is being recognized in the directions that sour gas technology is taking as we enter the 1990s. There are the "benefits" that yield returns; but there are also costs that are becoming more and more important factors in the equation.

The Return Factors

Net production of hydrocarbon from sour gas development decreases as the hydrogen sulphide content increases. Nonetheless, the return from hydrocarbon sales will continue to be a dominant factor in the economics of most sour gas developments. The exception is super sour gas which will be discussed shortly.

Because methane is the most common hydrocarbon component of sour gas, the market for this commodity will continue to be a controlling factor. As a "clean" fuel, methane is not likely to be in less demand in the 1990s and at present comparative fuel prices, the market is almost certain to remain at least buoyant. New technological developments in methane end use are therefore likely to remain as an important factor in the economics that drive sour gas development. Very recent developments(1) in the catalytic conversion of methane to C2 and heavier organics, some without accompanying CO2, production, suggest exciting new possibilities for ready conversation of methane gas to liquid fuels and petrochemical feedstocks.

Methane, however, is not the sale hydrocarbon component of sour gas. The richer the gas stream is in higher hydrocarbons, the more attractive it will be as a petrochemical feedstock for new developments in this area.