ALGERIA - ENIP - Skikda Ethylene Complex - profiles of the main plants run by ENIP and Sonatrach.

This consists of an ethane cracker producing ethylene, on stream since 1978, and downstream units. Under a contract signed in 1971, Toyo Engineering of Japan built the 120,000 t/y ethylene plant, and in 1979 brought on stream a 40,000 t/y vinyl chloride monomer (VCM) plant as well as a 35,000 t/y PVC unit. A 48,000 t/y low density polyethylene (LDPE) unit built by Snamprogetti of Italy started production in 1980.

The complex now has a 10,000 t/y hydrochloric acid unit. But the ethylene plant, based on the Bloomfield process (ABB Lummus Crest, NJ), could only run at 80% of capacity by the late 1980s. In early 1988, ENIP decided to build two more plants at the complex to produce 130,000 t/y of HDPE and 70,000 t/y of plastifiers.

For these ENIP had to expand the ethylene plant to 220,000 t/y. Stone & Webster in 1991 submitted plans to expand the plant in three phases: restoring its 120,000 t/y capacity, removing bottlenecks, and adding a 100,000 t/y capacity based on its Advanced Recovery System (ARS) - with all work to be completed in 1995. Due to delays, ENIP in 1994 set the completion date for early 1996, in time to supply the HDPE plant - and the cost of the project including the latter plant was estimated at $300m. Neither the ethylene expansion nor the HDPE plant was completed on schedule.

In December 2003 ENIP awarded Invensys a $2m contract to upgrade the outdated pneumatic boiler controls and burner management system at its Skikda complex. ENIP then said that was the first of several similar control projects which it planned to launch for Skikda and its Arzew complex.

Invensys said in a press release that, following a thorough technical and commercial review of several major automation vendors - including ABB, GE Fanuc, Honeywell, and Yokogawa - ENIP "determined that the combination of Invensys' Foxboro A2 automation system and TUV-certified, Triconex triple modular redundant (TMR) Trident safety shutdown system will provide the lowest cost solution that meets the company's demanding technical and safety requirements". The release quoted Said Adjilia, managing director at ENIP, as saying that, in addition to its "competitive price, appropriate control capability, and well-documented safety capabilities of their technical solution, we appreciated the fact that Invensys is widely recognised as a premier automation vendor with a long track record of successful projects".

Invensys said its scope of supply included: Foxboro A2 distributed control system with four operator consoles using "best-in-class Wonderware InTouch HMI software, four redundant controllers, and remote I/O for approximately 500 points; three Triconex Trident triple modular redundant (TMR) burner management safety systems with associated I/O; Foxboro intelligent transmitters, positioners and analysers, plus on/off and control valves; new burner pilots to make the existing boilers compliant with new international safety regulations; all cabling and related accessories; and training and site services". The new boiler control systems started up in 2004.