BJ Completes Gas Injection Compression Spread in North Africa

BJ Process and Pipeline Services (BJ PPS) has designed, built and commissioned a self-contained, temporary gas injection compression spread in the El Gassi Field, North Africa. Use of the new gas injection compression units to reinject 30 million cubic feet of gas per day into the reservoir greatly reduce the need to flare gas from the process facility, substantially reducing levels of gas flaring emissions.

Innovative Engineering Benefits the Environment
"We consider this 'Early Gas Injection' project a significant step forward in protecting the environment," said Lindsay Link, General Manager for BJ PPS. "To reduce the gas flared from 30 million cubic feet per day to near zero levels is outstanding news for the industry, as well as for the local environment. The fact that the unit is self-supporting and operates on fuel quality gas that the unit itself processes from product gas is an excellent example of how innovative engineering can benefit the environment," he added.

Currently, 30 mmsfcd from the El Gassi and adjacent Zotti fields is flared daily as a normal course of operating. However, in keeping with its environmental protection campaign to reduce polluting emissions globally, this operator retained BJ PPS to design, build, commission and operate the two gas injection compression units to carry out "early gas injection" services for 33 months from commissioning of the system.

Now that the gas injection compression spread has begun operating, BJ PPS uses the spread to repressurise 30 mmsfcd from very low supply pressures of 2, 4 and 39 bar, up to a high pressure discharge of 300 bar.g in order that it may be re-injected back into the reservoir. By doing so, the environmental emissions from the El Gassi LP and HP flares are being reduced to minimal levels.

Self-contained System
BJ PPS invested a great deal of careful planning in the design of the new gas injection spread, which consists of two main gas engine driven compressor units, a fuel gas treatment skid, a molecular sieve unit, electrical generators, instrument compressors and methanol injection. The design allows the units to operate independently of other external supplies by generating its own fuel gas for the engines from the same supply gas that is compressed and re-injected.

New Units Feature Most Powerful Engines in BJ Services Fleet
The two main gas compression units are the largest and most powerful to enter the BJ Services world-wide fleet, weighing in at over 184 tons each, driven by 4500bhp engines and measuring 120' long by 15' wide.

Key elements of each gas injection compression unit include: a Waukesha 16VAT27GL low Nox emission, turbocharged, natural gas-fuelled engine with a maximum power of 4500bhp; a Dresser Rand 7HOS-6 gas compressor; a Fintube cooler for process gas after-cooling; a Jacket Water Cooler; clean oil storage tanks, waste oil storage tanks and a glycol storage tank, among a host of additional items.

While primary support of the operation is being supplied by four specially trained, mechanical field supervisors on-site at El Gassi, BJ PPS personnel located at division bases in Hassi Messaoud, Algeria and Great Yarmouth, UK also provide ongoing assistance.

BJ Services Company (BJS-NYSE, CBOE) is a leading provider of pressure pumping and related oilfield services to the petroleum industry. The Company operates in every major oil and gas-producing region.