A book by Lieberman stresses that it is essential to make existing units work adequately and efficiently.Equipment that malfunctions or operates inefficiently limits production and does not permit optimalenergy and equipment utilization. This, in turn, leads to higher environmental degradation, not to mentionplant downtime and lost production costs. Lieberman concludes that good troubleshooting and adequaterepair of malfunctioning units are central to efficiently utilizing available resources.Due to an increase in the produced water feed rate at a Saudi Aramco gas plant, there was a need toinstall a new sour water stripper (SWS) unit to accommodate additional produced water. Based onoperational experience, the existing SWS was not performing as required, and a plan was made to install anew SWS to accommodate the total sour water feed rate. The validation of the actual capacity of theexisting SWS was important to confirm the processing capacity of the new SWS unit under the new projectinvestment. An assessment was conducted through design review and process simulation. Additionalverification was performed by conducting field capacity tests jointly with the gas plant and the lab team.Based on the assessment findings, it was concluded that the existing SWS unit was capable of handling5,000 bpd of sour water as per nameplate capacity, while maintaining H2S specification in the treatedwater. Although the existing SWS unit is capable of processing the sour water feed at its original designcapacity, some challenges, limitations, design deficiencies, and key operational issues need to beaddressed to sustain performance in the unit. Based on the assessment study, it was recommended toutilize the existing SWS with proposed design changes and to install a new, smaller SWS to treat theadditional water stream. This approach resulted in CAPEX savings for the company.The authors present their experience and lessons learned with the SWS that initially failed to achieve itsdesign goals due to multiple issues. The problems were correctly identified in a short, systematic, andeffective investigation that combined field measurements and testing with efficient hydraulic analysis. Theunit was successfully repaired and optimized, which helped the company avoid a CAPEX investment.
Tariq et al. (Sat,) studied this question.