MERC ER01-14
2
2. Introduction to Technology
Filtrex has developed its ACB filter as a tailored solution to fulfill the current and future
water treatment requirements. Filtrex micronic self-cleaning technology was developed in the
eighties for the filtration of lube oil and heavy fuel oil in marine applications for the military then
for merchant ships. In the ‘90s the same technology was applied in the oil and gas market for
process fluids filtration. In the last few years, the filter has been used for water treatment
(marine, brackish and fresh water). Noble material, as bronze-aluminum alloy, was chosen to
ensure durability, less maintenance and lower TCO (Total Cost of Ownership); maintaining at
the same time a small size, being made of few parts, and with low levels of backwash fluid. The
ACB filter flow rate range is from 6 to 3,000 m
3
/h.
The filter works “on-condition”, using the same filtered fluid for back washing. As more
and more impurities build up on the cartridge surface, the differential pressure (dp) gradually
increases, until it reaches the set-point value; at this set-point the cleaning phase starts. The
cleaning operation is made by a nozzle rotating inside the filtering element basket. While all the
filtering sectors of the filter element assure the filtration of the fluid, the sector in front of the
nozzle is cleaned by a high-efficiency backwash flow. The cleaning time lasts for a few seconds.
3. Summary of USCG and IMO Standards
This report refers to, and incorporates specifics guidelines and requirements found in:
•
International Maritime Organization (2008) Resolution MEPC.174 (58) Guidelines for
Approval of Ballast Water Management Systems (G8); and
•
ETV Generic Protocols for the Verification of Ballast Water Treatment Technologies,
(2010) EPA/600/R-10/146.
USCG Regulations and the IMO Convention both include the following ballast discharge
standards:
1) Less than 10 viable [live] organisms per m
3
, greater than or equal to 50 µm in minimum
dimension;
2) Less than 10 viable [live] organisms per ml, less than 50 µm in minimum dimension and
greater than or equal to 10 µm in minimum dimension and
3) Less than the following concentrations of indicator microbes, as a human health standard:
1. Toxigenic
Vibrio cholerae
(serogroups O1 and O139), less than 1 colony forming unit
(cfu) per 100 ml
2.
Escherichia coli,
less than 250 cfu per 100 ml;
3. Intestinal Enterococci, less than 100 cfu per 100 ml.
