Harn R/O Systems Blog

Introduction to a Harn R/O Systems Membrane Filtration Pilot Unit

Posted by Julie Nemeth-Harn on Nov 17, 2017 2:15:07 PM
In this RO pilot video, Jonathan Harn, project engineer with Harn R/O Systems, introduces one of our membrane filtration (MF) pilot units designed to operate standalone or as pre-treatment to our reverse osmosis (RO) pilot units. Membrane filtration is designed to remove suspended particles from water whereas reverse osmosis (RO) is designed to remove dissolved particles from water.

Related Blog: What is Membrane Water Treatment Technology and Why Do We Specialize In It? 



This MF pilot is a self-contained mobile MF system designed to operate a pressurized MF module to validate the proposed process design and gather actual operational data prior to large-scale plant design and construction. This pilot is designed to produce various filtrate rates up to a maximum instantaneous filtrate flow rate of 60 gpm. Microfiltration (MF) and Ultrafiltration modules can be operated on this pilot since the main distinction between MF and UF is membrane pore size and the size of particles that are removed, which has little impact on the pilot equipment requirements.

The MF/UF process has many different parameters that require site-specific optimization such as pre-treatment type, backwash frequency, Chemically Enhanced Backwash (CEB) frequency, CEB chemical type(s), Clean-In-Place (CIP) frequency, CIP chemical type(s) and many more. Optimizing these parameters prior to large-scale plant operation is extremely beneficial. The pilot is designed to operate either in dead-end or crossflow mode depending on the application requirements.

This pilot is designed to be non-proprietary and has the physical, hydraulic and process flexibility to accommodate inside-out, outside-in, PES, PVDF or ceramic modules from various manufacturers such as Dow, Inge, Toray, X-Flow and others. The physical dimensions and port orientations vary between module manufacturers. In order to accommodate both inside-out and outside-in modules from different manufacturers the feed/retentate and filtrate headers on the pilot are designed to be adjustable and removable with minimal modifications. This flexibility allows various module manufacturers and types to be tested during a pilot study.

This pilot is also designed to accommodate multiple modules so that filtrate flux and flow can be tailored to meet the application requirements. Space for two (2) modules is available on-skid and additional modules can be added to the skid with a sidecar attachment. If there is not a minimum filtrate flow requirement to support a downstream treatment process then one (1) module can typically be used. The filtrate flow can be varied to obtain a desired filtrate flux. If there is a downstream process that requires a minimum filtrate flow such as one of our NF/RO pilots then additional modules can be added so that the necessary filtrate flow can be produced at the desired flux.

The pilot has all necessary pumps, valves, piping, instrumentation, controls and compressed air system mounted on-skid for a fully functioning system and only requires a single 480V 3-phase 35 Amp electrical connection and process pipe connections. The optional feed and filtrate tanks are off-skid and may not be required depending on existing infrastructure available. The pilot has on-skid instrumentation necessary to monitor membrane performance and a PLC based control system and touchscreen operator interface. CIPs can be performed using the feed tank and on-skid equipment. An additional cleaning system is not necessary.

The typical pilot study duration is 3-6 months, however the system is capable of continuous operation indefinitely with minimal operational requirements for longer pilot studies that are necessary to evaluate seasonal water quality variations and other long term operational concerns.

Reverse Osmosis/Nanofiltration Pilot Unit Webinar

Topics: membrane filtration, membrane treatment, membrane treatment system, reverse osmosis, reverse osmosis pilot