Altagas – Harmattan Waste Heat Recovery Unit (WHRU)

Gas Liquids Engineering Ltd. (GLE) provided EPCM services for a brownfield project to modify an ethane extraction plant to increase production from 275 MMSCF/d to 400 MMSCF/d.

One component of the project was the installation of a 8MW Cleaver-Brooks MOH-8-2630 waste heat recovery unit (WHRU) to the exhaust of a Solar Gas Turbine Taurus 70 that was driving a refrigeration compressor, in a straddle plant. Recovered heat was later used in the heat medium system of the facility.

As refrigeration duties change with the ambient temperature throughout the year, heat recovered in the WHRU did as well. This unit needed to be designed accordingly with fluctuations in many areas of the facility and its effect in other areas also needed to be evaluated. The safe start-up and shut-down of the unit needed to be considered in the design as well. Valves needed to be switched to safe positions to minimize risks derived from handling air/fuel mixtures under LEL and UEL.

Due to limited space on site the WHRU was installed in a dead-end alley between two buildings, and could only be accessed from its south end. The WHRU had to be elevated to allow trucks to be able to drive underneath after installation.

Project scope included:

  • Removal of an existing underground tank and eight abandoned piles that were no longer utilized
  • Installation of new piles
  • Pouring of reinforced concrete foundation
  • Installation of shop fabricated structural steel support modules for WHRU
  • Installation of WHRU and associated equipment with the use of a crane