Construction Period : 25 Months


MAC was entrusted by Technip Abu Dhabi, as its main subcontractor, to execute the multi-discipline civil, buildings, mechanical, electrical, instrumentation, insulation and painting construction works for two new Sulfur Recovery Units at Saudi Aramco Riyadh Refinery. The Project consisted of:

  • Two new buildings : Electrical Substation # 88 and Process Interface Building (PIB) # 5, of a blast resistant design in reinforced concrete on a Lump Sum Turnkey (LSTK) basis including detailed engineering and construction of the buildings, plumbing, HVAC, electrical, grounding, instrumentation and communication works
  • A new Amine-Treating Unit (ATU-4) based on 50% wt MDEA solution comprising installation of: Flash drum, regenerator, overheads and reboiler systems, heat exchangers, filtration, chemical injection, storage, drains & fresh make-up facilities
  • Revamping of the existing Amine Treating Unit (ATU-2) by retraying Fuel Gas Absorber Regenerator to suit the revised loads/process requirements and hooked up with the new unit. The booster pumps in the existing hydrocracker unit were replaced
  • A shutdown period, involving execution of 123 tie-ins of the new units to existing systems. The tie-ins were subjected to special authorizations delivered by SAUDI ARAMCO/TECHNIP under strict Quality and Safety regulation
  • A new sour water stripper (SWS-2) with overheads and reboiler systems, raw & stripped water heat exchanger & associated systems.
  • As part of Sour Stripper (SWS-1) modifications, a new degassing drum was added for pumping degassed and skimmed sour water to new storage
  • Two Sulfur Recovery Units each of 70MT/day capacity with common KO drums receiving acid gas and SWS gas feeds from ATU-2, ATU-4, SWS-1 & SWS-2. Each SRU consisted of one thermal, three catalytic reactors & associated facilities such as a waste heat recovery boiler, sulfur condensers, reheaters, thermal oxidizer, thermal oxidizer stack, liquid sulfur degassing and storage pit, sulfur pumps etc.