Sour water stripping plant for a crude oil refinery

Date : Jan 2016 - Oct 2016

Among the vital units in a crude oil refinery, is the Sulfur Recovery Unit, where elemental sulphur is recovered from gaseous hydrogen sulphide. Part of the Sulfur Recovery Unit is the Sour Water Stripping Section which would treat sour water coming from various sources around the refinery. Sour water is basically waste water which contains H2S and NH3 and sometimes phenol which can be treated by stripping in a Sour Water Stripper to remove the H2S and NH3 content so that the water can be reused, further treated or discarded to sewerage if it met the required quality. The major objective of this project is the design of sour water stripping section to remove Ammonia and Hydrogen Sulfide from Sour Water before processing in Industrial waste water Treatment Plant or reusing as wash water in existing process plants in the refinery. This report involves brief overview of the process, prevalent process schemes, material and energy balances, process simulation, design and operating conditions, flow sheeting, material selection, flash drum, feed tank and stripper sizing, tray and heat exchanger rating, hydraulic calculations and pump design, HAZOP study, instrumentation and control strategies, costing and optimization and environmental constraints. Sour Water is produced at several locations inside a refinery where water comes in contact with H2S and or NH3. If un-stripped water is exposed to open atmosphere, NH3 and H2S are released to environment, resulting in unpleasant smell and safety concerns, as a result of these toxic emissions banned can be implemented by national or international legislative authorities and environmental protection agencies. As sour water treatment is very important in every crude oil refinery, it is therefore necessary to come up with an optimal design of sour water stripping systems.