TO SCRUB OR NOT TO SCRUB
By: Dr. John Kokarakis
The first meeting for the 2018-2019 season took place in the prestigious auditorium of the Angelicoussis Group of Companies kindly offered for the occasion. A record number of 175 attendees were present due to the criticality of the panel discussion.
The Impressive Building of Angelicoussis Group of Companies.
The panel was skillfully moderated by Panos Mitrou of Lloyd’s Register. The aim was to provide feedback from Class, Design Companies, Operators, Makers and Regulators. The discussion was opened by brief discussions by each panel member. An extensive summary of each panelist’s presentation follows.
Panos Mitrou covering the class aspect, underlined that not all refineries will follow the same strategy. This lack of flexibility can produce regional imbalances in fuel supply. There is going to be a premium on the price of MGO and low sulphur HFO compared to high sulphur HFO. The level of the premium is anybody’s guess. Charter rates will be affected depending on installation of scrubber or not on the vessel. The payback period will increase as the years go by and will be shorter in larger vessels with VLCC topping the list. Crews will have to deal with at least three types of fuel. An HFO supply chain will need to be maintained. Main risks focus on regulatory restriction of wash-water controls of discharge. The recent surge in scrubber installations is attributed to previous lack of action. The potential for postponement of the date of rule application appears to be remote to non-existent.
Stavros Hatzigrigoris, Managing Director of Maran Gas reflecting the operator’s point of view explained that open loop scrubbers must monitor continuously the ratio of sulphur oxides to carbon dioxide to check compliance. Scrubber increases sfoc by about 0.5 gr/kwhr. Redundancy is a must in the pumps supplying sea water to the scrubber. An enlarged sea chest or a dedicated one must serve these pumps. Decisions must be made on sizing on the basis of operational profile for M/E & DGS estimating the amount of exhaust gases, the added back pressure, expected utilization and/ trading areas, type of scrubber (in line, U-Type), number of wash-water pumps, air seal fans, by-pass mode necessary for U-Type, consideration for extra steelwork, maintenance cost and inspection requirements, maker’s previous experience. The engineering study must include class consideration and selection of design outfit, effect on existing systems (electrical power needs, added backpressure, SFOC increase etc.), risk analysis, 3D scanning, consideration for drydocking or works afloat, selection of Owners supplied items (GRE pipes, exp. bellows, electrical equipment, cables, special steel piping, valves, other fittings). Preparation must include yard selection, forwarding considerations and recourses. Important points are also the site team requirements, maker’s attendance, pre-commissioning checks, crew training for safe operation, duration of commissioning and sea trials (level of sulphur in bunkers).
Mr. Karabinis representing the makers (Wartsila) clarified that almost 1500 scrubber systems are currently fitted or on order so far, i.e. less than 5% of existing fleet and about 28% of newbuilding orderbook. Most new-buildings are fitted with scrubber systems even smaller DWT ships such as Ultra-max Bulk Carriers. Wartsila presented the various phases of retrofit scrubber installations and various available services including financing. Maker advised early move to gain more experience and avoid bottle-necks.
Vassilis Dimoulas also from Class (BV) focused on design and certification issues. He explained that according to MEPC .259(68) certain documentation must be approved by the administration or RO for Scheme B Certification. In the case of EU flagged vessels MED certification is also applicable. Maker has to contact Class as early as possible with all info necessary to complete the statutory certification. The design review by Class involves specialists in hull structure, machinery /fire safety, electrical & automation, stability and others (e.g. Tonnage). Important issues are the bypass arrangements and isolation of pipes with target the prevention of gas back-flow, wash water pipe material, sea chest arrangement and ship side valves construction and control. Study must include number and location of overboard discharge pipes. CFD calculations can support the correct placement. According to IACS UR P4, fire hazard considerations dictate that in composite sea water pipes in engine room, ship side valves must be controlled remotely outside the engine room.
Stamatis Fradelos of ABS discussed extensively the regulatory scope of compliance. Starting with IMO requirements, he clarified that Class can approve on behalf of flag when authorized. Flag is then requested to notify IMO their acceptance listed in Global Integrated Shipping Information System (GISIS). Upon successful commissioning an IAPP certificate is issued. Use of scrubbers in the USA is regulated by USCG and EPA. California does not allow use of scrubbers in regulated waters. The discharge of wash-water is governed by U.S. EPA 2013 Vessel General Permit. In EU, countries in the Baltic ECA do not allow discharge of wash-water. Compliance is ensured by continuous monitoring of emissions and discharge. Last but not least important exemptions and contingency measures were discussed.
The second phase of the panel discussion was followed by a tsunami of questions from the attendees and replies by the panelists. Some critical topics discussed were the interaction of scrubber with the other equipment in the exhaust gas network of ducts, innovations in scrubber design as well as fuel availability and compatibility. Overall, the event was a great success due to the synergistic efforts of SNAME members, student volunteers, SNAME personnel, the panelists and the attendee contributors to the discussions. The evening closed with fruitful social reception and net-working finger-food catering. SNAME is grateful to our hosts, panel moderator Mr. Mitrou, all panelists. Our aim is to organize such interactive type meetings in the near and far future.
The SNAME Greek Section Scrubber Technical Forum attracted the interest of the entire Greek shipping community.
Dr. Kokarakis, the SNAME Greek Section Chair, welcomes the panelists
The presentations can be found here.