(69a) A Self-Cleaning, Durable, High Flux Microfilter
AIChE Spring Meeting and Global Congress on Process Safety
2021
2021 AIChE Virtual Spring Meeting and 17th Global Congress on Process Safety
Industrial Wastewater Management and Water Reuse Topical Conference
Industrial Water and Wastewater Treatment and Reuse
Tuesday, April 20, 2021 - 3:00pm to 3:20pm
Membrane filtration is typically operated either in a dead-end or cross-flow mode. In these systems the
biggest problem in applications with relatively high suspended solids concentration is low flux, and
subsequent fouling or clogging. Because of this, particularly for dead-end systems, the membrane or
filter has to be either cleaned via chemical means or replaced often. Other options are based on
mechanical self-cleaning filters which do not go to low enough micron ranges, often 2 micron, for reuse
or injection and thus labor and cost intensive alternatives like bag or sand filters are still commonly
used. Sofi Filtration Ltd has developed an innovative industrial water filter to address the filtration
challenges of small particle size, and high or variable concentration streams. The design criteria for the
new filter was to accomplish a cross-flow filter that is compact and fully automated with a high
microfiltration capacity and novel clean-in-place abilities to prevent clogging. The unit requires no
internal moving parts to implement the design thus making it robust and economical to use.
The filter is differentiated in its performance from other screens, filters, and bag filters by this design. In
cross flow mode, the feed flow is accelerated within a filter element housing across the exterior of a
cylindrical filter element. Over time, as the pressure increases, a self-cleaning cycle is initiated. A high
powered, ultrasonic cleaning element, on the filtrate side, is started to loosen materials which may be
causing fouling or clogging the sintered metal screen. After a designated time, while the ultrasound is
still on, a back pulse of around 90 psi creates an impact in less than one second to efficiently remove
material from the screen. After these 2-steps, the system returns to normal filtration operation.
Feedback control ensures appropriate timing of cleaning intervals to maintain filtrate flowrates to
manage variable influent solids loadings.
A Sofi Filter unit including a multi-layer metal membrane with nominal pore sizes from 0.5 to 10 microns
has been installed in several applications including saltwater disposal wells for Produced and Flowback
water. Filtrate flowrates up to 2.5 BPM (100 gpm) were measured for a 1 m2 filter element with a
nominal 0.5 micron pore sizing. Being of all metal construction without the need for operator
intervention due to newly developed smart feedback controls, this system seems poised for more
deployments in the upstream and midstream markets.
Furthermore, Sofi Filtration has recently established a technology facility in the Houston area to further
assess the US market applications with Sofi Filter test unit. Test capabilities are initially from 0.5 to 10
micron filtration rating. The facility has full laboratory capabilities for application testing.
biggest problem in applications with relatively high suspended solids concentration is low flux, and
subsequent fouling or clogging. Because of this, particularly for dead-end systems, the membrane or
filter has to be either cleaned via chemical means or replaced often. Other options are based on
mechanical self-cleaning filters which do not go to low enough micron ranges, often 2 micron, for reuse
or injection and thus labor and cost intensive alternatives like bag or sand filters are still commonly
used. Sofi Filtration Ltd has developed an innovative industrial water filter to address the filtration
challenges of small particle size, and high or variable concentration streams. The design criteria for the
new filter was to accomplish a cross-flow filter that is compact and fully automated with a high
microfiltration capacity and novel clean-in-place abilities to prevent clogging. The unit requires no
internal moving parts to implement the design thus making it robust and economical to use.
The filter is differentiated in its performance from other screens, filters, and bag filters by this design. In
cross flow mode, the feed flow is accelerated within a filter element housing across the exterior of a
cylindrical filter element. Over time, as the pressure increases, a self-cleaning cycle is initiated. A high
powered, ultrasonic cleaning element, on the filtrate side, is started to loosen materials which may be
causing fouling or clogging the sintered metal screen. After a designated time, while the ultrasound is
still on, a back pulse of around 90 psi creates an impact in less than one second to efficiently remove
material from the screen. After these 2-steps, the system returns to normal filtration operation.
Feedback control ensures appropriate timing of cleaning intervals to maintain filtrate flowrates to
manage variable influent solids loadings.
A Sofi Filter unit including a multi-layer metal membrane with nominal pore sizes from 0.5 to 10 microns
has been installed in several applications including saltwater disposal wells for Produced and Flowback
water. Filtrate flowrates up to 2.5 BPM (100 gpm) were measured for a 1 m2 filter element with a
nominal 0.5 micron pore sizing. Being of all metal construction without the need for operator
intervention due to newly developed smart feedback controls, this system seems poised for more
deployments in the upstream and midstream markets.
Furthermore, Sofi Filtration has recently established a technology facility in the Houston area to further
assess the US market applications with Sofi Filter test unit. Test capabilities are initially from 0.5 to 10
micron filtration rating. The facility has full laboratory capabilities for application testing.