Retrofit Solutions

Engineering and Retrofit solutions

Retrofit Maripur® Advanced Wastewater Treatment Systems

The Retrofit Maripur® advanced wastewater treatment plants are designed to reduce the cost of installing wastewater treatment equipment into existing vessels. Each standard Maripur® size in the range is available for adaptation to a bespoke retrofit requirement and all come fully certified to IMO MEPC 159(55). Dependent upon the design and access limitations for any given vessel, ACO Maripur® can be delivered in anything from two to five (for the larger Maripur® sizes) independent watertight tank modules which are fully tested for both hydrostatic and weld penetration requirements. Separate tank modules are then simply bolted together at the final installation site and connected by external piping. Under normal circumstances, there is no requirement for any hot work at the installation site. Dimensions for each component tank are arranged to permit its transportation through standard access ways or to minimise hull opening sizes during vessel dry docking.

Retrofit Maripur® is specified, installed and commissioned working in close co-operation with the world‘s leading ship owners, operators and shipyards. The combination of a biological process with ultra-filtration of the treated water – without any final clarification or additional disinfection – meets and exceeds the quality standards of IMO/MARPOL, HELCOM, USCG, US Federal Law Gazette No. 40, section 133, Australian ADNOC and Australian Federal Environmental agency and the Alaska requirement. Fully type approved in accordance with IMO MEPC 159(55) detailing new test and discharge standards for sewage treatment plants installed on, or after, 1st January 2010.

Standard Features 

  • IMO MEPC 159(55) & MED Module B (wheel mark) certificate issued by DGUV, Germany
  • No requirement for chemicals, chlorination or de-chlorination in the treatment process
  • Compact Modular construction design optimised for marine applications
  • Single power supply input point, stand alone ‘PLUG & PLAY’ installation
  • Minimal maintenance requirement
  • High Head capability progressive cavity effluent discharge pump
  • Entirely EU sourced and manufactured
  • Tank materials al in stainless steel AISI 316
  • Fully automated PLC Logic Control System
  • Application range: 25 – 250 PE (or up to 625 PE on vacuum black water only)
  • Size range: ACO MARIPUR® 25, 50, 75, 100, 150, 200 & 250

Effluent quality significantly better than the IMO standard

IMO MEPC.2(VI) USCG 33CFR 159 PT1-300 USCG Alaska 33CFR 159,309 IMO MEPC 159(55) IMO MEPC 227(64) ACO Maripur IMO MEPC 227(64) certified values
Coliform bacteria (n/100ml) 200 200 20 100 100 17,3
Total Suspended Solids (mg/l) 100 150 30 35 35 2,4
BOD5 (mg/l) 50 30 25 25 7,3
COD (mg/l) 125 125 60
pH Not req´d Not req´d 6-9 6-8,5 6 – 8,5 7,3
Chlorine (mg/l) As low as practicable Not req´d 10 < 0,5 20,5 Zero
Ntot (mg/l) 20 7,2
Ptot (mg/l) 1 0,3

Reference installations

  • Super and Mega Yachts
  • Cruise vessels (up to approx. 1500 people)
  • River Cruise Vessels
  • Military Vessels
  • Offshore Installations and Vessels
  • Specialist vessels such as sail training ships, survey vessels, conference ships, etc

Retrofit membrane “polishing” units For vessels in-service with existing ‘conventional’ sewage treatment plants ACO Marine are able to offer membrane ‘polishing’ unit(s) to additionally treat discharges from conventional unit(s) to meet the IMO MEPC 159(55) standards and better. For details please contact us with your specifications and requirements