Carollo Engineers’ custom membrane pilot plants (CMPPs) provide a unique means of evaluat-ing low-pressure (microfiltration and ultrafiltration) membrane modules operating in a dead-end mode from multiple membrane manufacturers. Carollo designed the CMPPs to accommodate a wide range of pressurized membrane modules. Carollo has used the CMPPs in the evaluation of membranes of various surface area, configuration, and flow pattern. The CMPPs are often used to develop design criteria for a range of membrane modules in order to identify the most cost-effective solution. Design criteria in these evaluations include optimization of the permeate flux and the system recovery. The CMPPs are also used to optimize backwashing procedures to minimize backwash wastewater production. These investigations include:

•  Backwash chemical dosing strategy

•  Backwash flow rates and durations (for both air and water).

•  Recovery.

The CMPPs have also been used to evaluate various chemical cleaning strategies. Important considerations with respect to chemical cleaning include the cost of the chemicals and disposal requirements. Chemical cleaning optimizations involve the examination of:

•  Sequence of chemical addition

•  Chemical dosages

•  Temperature.

•  Duration of each phase of cleaning.
The CMPPs are equipped with remote data acquisition and control (RDAC) systems, which include a programmable logic controller (PLC) and data logging system to monitor operational parameters at user-defined intervals. Critical operating parameters, such as flow rates, flux, transmembrane pressure, and temperature are displayed in real time in a graphical format using a human-machine interface (HMI), or accessed remotely. In addition, water quality data, such as permeate turbidity and particle counts are also continuously measured. All data, control functions, and operating parameters can be monitored or adjusted remotely via a website-based or dial-up connection. Sample Collection For quality assurance and control purposes, pressures, temperatures, and flows can all be manually checked and compared to transmitter readings on the pilot plant. Sample taps located on the pilot plant also provide access to feed, permeate, and backwash water for quantification of water quality parameters. Waste streams from the cleaning process may also be collected for pH adjustment prior to disposal. For quality assurance and control purposes, pressures, temperatures, and flows can all be manually checked and compared to transmitter readings on the pilot plant. Sample taps located on the pilot plant also provide access to feed, permeate, and backwash water for quantification of water quality parameters. Waste streams from the cleaning process may also be collected for pH adjustment prior to disposal.