Page 14 - Opportunities in the Treatment of Water and Other Wast Streams

• Moderate energy demand • Material susceptible to damage • Require chemicals for cleaning
Membranes are classified by the size of the particles that they exclude. Microfiltration and ultrafiltration filter larger particles and are thus only used for pretreatment or removing particulates. These membranes use pressure or suction to filter water through a porous membrane. Membranes can be made from either polymeric or ceramic materials. Ceramic materials have a longer lifetime and can be cleaned with more aggressive chemicals, but they generally cost more than polymeric materials.
As the required footprint per volume of water treated is relatively smaller than traditional media filtration, microfiltration and ultrafiltration modules are commonly combined with other treatment processes in containerized trailers for on-site produced water recycling treatment, such as hydrocyclones for sand and oil separation, followed by microfiltration or ultrafiltration for smaller particles and colloidal material, before a desalting process.
Application:
Why: Pretreat water and remove organic matter before ultra or microfiltration and reverse osmosis treatments.
Where: Off-site treatment facilities (due to sensitivities in transporting cultures and stabilizing inflow water qualities).
Target Contaminants:
• Oil, grease, and hydrocarbons
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