Produced water management is essential for the sustainable development of oil and gas resources. Enhanced oil recovery projects that use Once-Through Steam Generators (OTSG’s) for steam production are often left with high volumes of disposal brine. Aquatech’s Once-Through Flash technology is designed to be paired with the Once-Through steam generators to convert their blowdown water back into feed water. Not only is the blowdown water recycled, but the thermal energy inherent in the blowdown water is also beneficially used to self-induce water recovery through evaporation. As a result, the Once-Through Flash Evaporator Systems operate at power consumptions of 20-40 percent less than conventional evaporators.
Once-through flash is an innovative process used in enhanced oil recovery projects where it is designed to recycle the thermal heat produced by Once-through Steam Generators (OTSGs) that are used extensively in the Alberta Oil Sands market. This recycled heat is then used to convert produced water into clean water with high purity.
“Based on the proven and robust Vertical-Tube Falling Film design principles, the once-through flash technology reduces power consumption by 20-40 percent, lowering OPEX. In addition, it features a simpler process configuration than conventional designs and is able to deliver a substantial capital cost savings that can reduce CAPEX by more than 10 percent,” stated Greg Mandigo, Applications Engineering Manager, Upstream Oil & Gas, Aquatech.
Once-through flash also yields water recycle rates of more than 95 percent, thus achieving compliance with the Alberta Energy Regulator’s Directive 081 that sets water disposal limits and includes detailed reporting requirements for thermal in situ oil sands operations. Once-through steam generators typically allow recovery rates between 80-90 percent.
Once-Through Flash Key Applications
- Steam-stimulated EOR market
- Applicable to any EOR project that utilizes a Once-Through Steam Generator
- Immediately valuable in Alberta due to Directive 081 Regulation