This paper discusses hydraulic and water quality
performance data gathered during a six-month pilot study in Kansas City which demonstrates that
retrofitting granular media filters with low-pressure membranes in large plants can be an important tool to
meet ever-increasing regulatory requirements while substantially increasing plant capacity. Specific objectives of
the project were to:
develop full-scale membrane system design for retrofitting the Kansas City Water Services
Department (KCWSD) water treatment plant with membranes selected for specific characteristics that
make them well suited for the application, including high permeability, high fiber
packing density, and chemical compatibility;
develop conceptual layouts detailing both gravity-fed and pumped membrane retrofit scenarios at
KCWSD based on the design parameters developed during pilot testing, including an
analysis of integration issues such as the use of existing infrastructure, ancillary equipment
requirements, membrane integrity testing protocols, and operator training requirements; and,
develop cost estimates for retrofitting existing granular media filters with membrane media filters at
the KCWSD water treatment plant. Membrane pilot testing was conducted at KCWSD's 240-million gallon per day (mgd) lime softening
plant, which draws water from the Missouri River. Three low-pressure membranes were pilot-tested at KCWSD: Hydranautics UF Hydracap 60 (INDECK)2;
Polymem UF 120S3 (WESTECH)2; and, Zenon ZW-1000 (ZENON)2. The three membranes were chosen
because they encompass two membrane system alternatives that may be particularly suitable for retrofit
designs: submerged membrane systems; and, custom designed, pressurized vessel membrane
systems. The pressure driven systems were evaluated under low flux, low feed pressure conditions that would
permit their operation within the existing hydraulic grade line at the plant. All three membrane systems
were then evaluated under high flux, high feed pressure, or permeate vacuum conditions to maximize
capacity of the membrane modules and to establish design parameters for a pumped scenario. Three
operational criteria were maintained throughout pilot testing:
clean-in-place (CIP) interval e 30 days;
recovery e 90 percent; and,
total chlorine concentration in the backwash wastewater d 2 milligrams per liter (mg/L) greater than
the feed concentration. Includes tables, figures.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 470 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 10 |
| Published : | 06/17/2005 |
