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Ref. No. [UMCES]CBL 12-005
1
1.0. MERC Background and Objectives
The Maritime Environmental Resource Center (MERC) is a State of Maryland initiative
that provides test facilities, information, and decision tools to address key environmental issues
facing the international maritime industry. The Center’s primary focus is to evaluate the
mechanical and biological efficacy, associated costs, and logistical aspects of ballast water
treatment systems and the economic impacts of ballast water regulations and management
approaches. A full description of MERC’s structure, products, and services can be found at
www.maritime-enviro.org.
To address the need for effective, safe, and reliable ballast water treatment systems to
prevent the introduction of non-native species, MERC has developed as a partnership between
the Maryland Port Administration (MPA), Chesapeake Biological Laboratory/ University of
Maryland Center for Environmental Science (UMCES-CBL), U.S. Maritime Administration
(MARAD), Smithsonian Environmental Research Center (SERC), and University of Maryland
(UMCP, UMWREC) to provide independent performance testing and to help facilitate the
transition of new treatment technologies to shipboard implementation and operations.
The following report describes the evaluation of filter performance for a proof-of-concept
demonstration of the potential for the BOLL Automatic Filter Type 6.18.3 to remove ballast
water organisms. Detailed protocols and formal MERC Test Plan can be downloaded at
www.maritime-enviro.org.
2.0. Introduction to BOLLFILTER Technology
The BOLL Automatic Filter Type 6.18.3 system contains bipolar filter candles, which are
open at both ends allowing water to flow through from either end during filtration. The filters
utilized a 40-micron mesh and a large surface area with a flow capacity of 3,000 m
3
per hour.
The system utilizes the bipolar filtration method in conjunction with bipolar backflushing.
Rotating flushing arms are fitted both above and below the filter unit. The filter candles are
cleaned alternately from above and below with the filtrate fluid without interrupting filtration.
The filter housing is compact and made of carbon steel.
3.0. Summary of Test Protocols
Five trials were conducted, three in March 2011 and two in June 2011. Water was
continuously pumped sea-to-sea, from Baltimore Harbor area (Patapsco River, MD, in the
mesohaline region of the Chesapeake Bay) into the US Maritime Administration vessel
MV Cape
Washington’s
ballast system via the sea chest.
The duration of each trial (from 3 to 6 hours) depended upon a specific filtered volume of
1,000 m
3
, pressure, and flow rate. Water samples were collected before (ambient) and after (post
40 µm) the BOLL filter, then analyzed for total suspended solids (TSS), particulate organic
carbon (POC), zooplankton greater than 50 µm (microns), and phytoplankton (10 to 50 µm and 5
to 10 µm). Further details can be found in associated Test Plan.