FMC’s High Salt Concentration Wastewater from Carrageenan Production is No Match for ADI-MBR
Location: Philippines • Sector: Food & Beverage
FMC Marine Colloids Philippines, Inc. (FMC) is a carrageenan production facility located in Cebu, Philippines. With 60 years of experience, FMC has become the largest and most experienced producer of carrageenan extracts worldwide.
The Client's Needs:
FMC needed to upgrade its existing wastewater treatment plant and investigated the best way to meet that need. The ADI-MBR process was considered to be superior to conventional activated sludge systems due to its compact footprint and capability of meeting the effluent permit limits while treating high total dissolved solids (TDS) and salt wastewater.
Wastewater with high TDS levels due to inorganic salts tend to be inhibitory to bacteria and frequently result in floc dispersion and an increase in effluent suspended solids. The MBR system uses the physical barrier of the membranes to restrict the solids from leaving the reactor and increase the biomass inventory in the system.
Following a successful MBR pilot study, FMC contracted ADI Systems to proceed with a full-scale MBR system. ADI Systems completed the full engineering design of the MBR system, including the supply of Kubota membrane cassettes. FMC constructed its own tanks, with ADI Systems supplying the dimensions, piping arrangement, and construction details.
The system consists of two MBR tanks in parallel, each with a preaeration and a membrane compartment. The membrane compartment of each tank is equipped with six ES200 Kubota flat-plate membrane cassettes, operated under gravity head (i.e., no permeate pumps). The MBR system is complete with influent pumps, preaeration and membrane compartment aeration blowers, process piping and valving, a membrane cleaning chemical system, and instrumentation and controls.
The MBR system was designed to treat FMC’s high salt concentration wastewater with 4,500 mg/l COD, 1,100 mg/l BOD5, 30,000 mg/l TDS, and 1,200 mg/l TSS concentrations at a flow rate of 465 m3/d (123,000 gpd).
After several years of being in operation, the MBR system is still performing exceptionally well treating this unique and challenging wastewater. The MBR is currently treating flows up to 25 percent higher than the design values and consistently complying with the effluent discharge requirements.
The effluent is discharged to the Mactan channel, which leads to the ocean. The effluent limits are less than 100 mg/l BOD5 and 150 mg/l TSS, and the high-quality effluent being discharged averages 10 mg/l BOD and 2 mg/l TSS.
Because the effluent coming from the MBR system is of such high quality, the plant has been recycling 30-40 percent of the effluent into the production process without any problems. Also, after seven years of operation, only 30 membrane cartridges out of a total of 2,400 (1.25 percent) have been replaced.
In 2012 FMC Philippines was recognized by the Department of Environment and Natural Resources with an award for its environmental stewardship, due in part to the superior effluent quality produced by the MBR system.