Koninklijke Vereniging - Société Royale



Aiming at the large vessel market

There is a lot of misinformation given about ballast water treatment systems (BWTS), Andrew Marshall, CEO of Coldharbour Marine, claimed at a recent company presentation.

While there are several good UV and electrochlorination systems on the market, there were also many that are simply not up to the job, he said.

Due to faulty equipment and lack of investment, he predicted that only around 15 manufacturers would be left in the market out of the many that have advertised BWTS to owners and shipyards in the past few years.
He stressed that owners must do their homework when selecting a suitable system for their vessels’ needs, as many BWTS fitted on large ships were not fit for purpose and simply do not work, as outlined in several reports, including a recent study by ABS.

The operating parameters of the vessels need to be taken into consideration, such as vessel type, voyages to be made, the types of water to be encountered, ie warm or cold or both, etc.

A selection made simply on price and a Type Approval certificate will almost certainly guarantee failure, he said, warning that owners faced a perfect storm of delays, disruptions, additional costs, significant losses, large fines (up to $100,000 at each de-ballasting) and loss of reputation, should a BWTS be found to be faulty during a Port State Control inspection.
Owners will have no recourse to BWTS manufacturers or shipyards should a failure or detention occur, he said, adding that P&I Clubs have also warned that they will not cover losses incurred as a result of improper equipment selection by owners. Badly fitted systems will also cause a malfunction, which could result in a PSC detention and or fine.

Coldharbour started work on a BWTS some 10 years ago, basing it on the company’s marine inert gas systems. It became an independent company in 2010. Apart from inert gas systems, in its 35 years of existence, the company has also produced land-base water treatment systems and flue gas technology.

Early on in the BWTS development, a decision was taken to concentrate on the larger vessel size ranges, of around Aframax and Capesize bulkers and upward, including LNG carriers. This only gives Coldharbour around 15% of the market, Marshall explained.

These types of vessels normally have specific operating requirements, such as long ballast voyages, a large ballast intake and high pumping capacities. Marshall explained that Colharbour’s BWTS needs a ballast voyage of more than five days to operate correctly in killing off all of the organisms to be found in ballast water.

For example, a VLCC will take on around 100,000 tonnes of ballast and have a maximum pumping capacity of 6,000 cu m per hour, taking around 18 hours to ballast at a terminal. Usually the timing is critical while alongside a terminal, so any malfunctioning equipment could have severe consequences. In addition, the crew are usually at saturation point with work while the vessel is alongside.

Down the years, investors have come on board and are reported to be happy with the progress made, thus far. Marshall explained that Coldharbour doesn’t expect to see a return on investment for another five years, as the Nottinghamshire plant’s business plan is to produce around 50 systems a year.

He claimed that Coldharbour was only the second company to be UK Maritime & Coastguard Agency (MCA) type approved, through Lloyd’s Register. The company was also the first to fit a BWTS on board a VLCC.

USCG stance

As for the US Coast Guard (USCG) Type Approval, Marshall said that the only real difference between that and the IMO Type Approval was a more stringent laboratory test.

For the USCG, Coldharbour is to undergo laboratory testing in tanks at NEA, Holland next year with the aim of becoming Type Approved during the first quarter of 2019. It already has Alternate Management Systems (AMS) status approval.

To help gain USCG Type Approval, Coldharbour is to install a BWTS on board the TMS Tankers managed 2013-built Suezmax ‘Bordeira’ in early 2018. The on board test will also be supervised by LR, which has Independent Laboratory Approval status with the USCG.

The IMO’s revised G8 certification tests agreed at MEPC last year will be undertaken simultaneously.

Evangelos Sfakiotakis, TMS Tankers’ Technical Manager, explained at the time of the announcement: “We have carried out a careful assessment of the available technologies for our large tankers and have satisfied ourselves with Coldharbour’s inert gas-based system. There are several reasons for this, but the two main ones are; firstly, that the Coldharbour technology featuring the combination of no filters plus in-voyage treatment process guarantees that our ballasting operations will never be disrupted, and secondly, that the treatment during voyage avoids the potential risk of regrowth during a long ballast voyage.

“This ensures that not only will our tankers be able to meet required discharge standards at all times, but also that we can be absolutely certain that the commercial availability of the vessel will never be adversely affected by BWTS issues,” he said.

As for the ease of installation, Marshall said that the system was ideal either for newbuildings or retrofits, as it offers flexibility in its location on board ship and is immune to space constraints being modular.

In addition there are no additional power requirements to operate the system, no filters, no pressure drop and no connections to ballast lines.

For newbuilds, there is no change needed to the existing pump room design, while for retrofits the systems is claimed to be easy to install in a 15-day window. The primary drivers for newbuildings are the shipyards equipment suppliers lists, which are often ‘set in stone’ by the yard, the ease of installation, the impact on other equipment choices and the vessel’s design and the equipment’s cost.

Retrofit considerations

As for retrofits, the owners take over the equipment suppliers lists. The main drivers are - the installation time required, impact on existing equipment on board, installation costs and the cost of the BWTS itself.

When considering an installation, as well as using computer aided drawings of the ballast tanks, a model of the actual ship’s internal tank layout will be constructed by way of a comparison.

Treatment at any stage during a ballast voyage means that the risk of regrowth is eliminated. The costs associated with regrowth, resulting in non-compliance are very significant and the ramifications are far-reaching, as mentioned above.

Marshall explained the re-growth in a ballast tank will occur. In the winter months the chances of regrowth were low but in the Spring and Summer it was high, he said. Corrosion in the ballast tanks will be eliminated, due to the lack of oxidisation.

Coldharbour is expanding its engineering teams and has signed agreements with two service providers, thus far.
For example, in May of this year, Coldharbour signed an agreement with Sembcorp Marine.

As a result, the latter will offer the GLD BWTS as part of the Sembcorp Marine Green Technology Retrofit (GTR) solutions for shipowners.
GTR provides carefully evaluated BWTS from a select group of equipment manufacturers with whom Sembcorp Marine is working closely.

To help cover the Chinese market Coldharbour also signed an agreement with Hansun (Shanghai) Marine Technology. This agreement covers the marketing and distribution of Coldharbour products in mainland China.

At the time of the agreement signing earlier this year, Hansun Chairman, Simon Gu, said: “Our existing products are already well-known for their reliability and operational advantages for shipowners. Adding the Coldharbour’s inert gas, flue gas, BWTS and domestic water module product lines means that we now have a comprehensive catalogue of products for our customers, from incinerators to the latest IGG units, from ultra­violet BWTS for small and medium sized ships, to the Coldharbour GLD inert gas-based in-tank BWTS for the largest vessels. We believe that this places Hansun in a unique position to supply the needs of our Chinese customers.”

This agreement is the first step in a plan that will eventually see Hansun manufacture Coldharbour units at its facilities in Qi Dong, with Coldharbour in turn offering Hansun products to its customers outside China. Training of Hansun sales engineers and project engineers is ongoing.


Inert gas
As mentioned, Coldharbour’s BWTS is based on an inert gas system with the company’s patented third generation Sea Guardian being an integral part of the ballast water equipment.

GLD is claimed to be unique in that it is an in tank and in voyage system using the gas output from Sea Guardian, which is linked via a specially designed Gas Lift Diffusion (GLD) pipe assemblies inside the water ballast tanks.

As the inert gas diffuses into the ballast water, oxygen is stripped from the water, whilst the elevated CO2 in the inert gas temporarily reduces the pH level. This induces Hypoxia and Hypercapnia, which is fatal to both aerobic and anaerobic organisms, Coldharbour explained.

Bacteria, for example E.coli, are killed in side the GLD by a patented method of gas-induced ultrasonic shock waves, which cause cellular destruction. The ultrasonic generators do not require power and have no moving parts.

They have been designed to operate inside the ballast tank’s harsh environment for many years.
When combined with a GLD BWTS, Sea Guardian provides clean low oxygen (0.2%) inert gas to operate the ballast water treatment system, while still having sufficient capacity for the bulk inerting of cargo tanks when required.

The IGG is capable of operating efficiently at 50% of maximum capacity for BWTS operation using pre-programmed automated settings protocols. Coldharbour claimed that compared to a more traditional BWTS solution, the combined system has a much smaller footprint with the added advantage of the units located downstream of the IGG being less bulky.

In addition, there is an added operational bonus in that the IGG has been designed without a burner cone, no separate scrubber tower unit and no demister pads, resulting in very low maintenance costs and little downtime, the company claimed.

Sea Guardian can be configured to use low sulfur MDO/MGO and LNG, including boiloff-gas. This multi-fuel capability further enhances the system’s efficiency and reduces operating costs, Coldharbour said.


Combined solution benefits include-

  • One IGG unit provides inert gas for both bulk inerting and ballast water treatment.
  • Units downstream of the IGG are compact, compared with traditional systems.
  • The IGG is a multi-fuel system, running off LSMDO/MGO and LNG, including boil-off-gas.
  • Used on each ballast leg for BWTS duty, the IGG is protected against maintenance and downtime issues caused by long periods of inactivity.

Advantages of an ‘in tank’ solution

Essentially, Coldharbour’s patented inert gas generator-based GLD BWTS is an ‘in tank’ solution. Being ‘in tank’ rather than ‘in line’, it offers the following solutions and advantages, the company claimed:

  • Maintaining uninterrupted ballast flow on a terminal and very high ballast pumping rates (>5,000 cu m per hour)
  • A combination of no connection to ballast lines and no in line filtration requirement equals no risk of disruption to ballasting operations, regardless of ballast flow rates.
  • Highly challenging and variable ballast water characteristics (salinity,temperature, suspended solids levels, biota)
  • Unique, patented Inert gas and gas ultrasonic disruption ‘kill’ technology is immune to variations in temperature, salinity, suspended solids or organism types.
  • A 100% kill guarantee is not possible with any BWTS technology, as long ballast voyages offer significant opportunities for organism regrowth.
  • Treatment during a voyage eliminates risk of organism regrowth, even on the longest ballast legs, as the organisms do not get the opportunity.
  • Use of Inert gas as an enabling technology means that tanker crews are already familiar with the basic principles of this equipment.
  • Existing ‘fixed’ architecture and linked equipment (space, power, pressure).
  • Modular construction, plus no requirement for connections to the ships ballast systems means that installation locations are not constrained and existing ships systems will not require expensive upgrades.
  • Treatment during ‘off peak’ vessel operations ensures that crew are able to cope with the new BWTS demands.
  • Scaling of other technologies is challenging (in some cases impossible). The GLD system has already demonstrated full capabilities on a VLCC of 308,000 dwt.
  • ‘Absolute’ nature of the legislation that requires compliance at all times. GLD is claimed to be the only system to offer the owner absolute assurance of compliance.
  • Automatic tank monitoring and simple user interface ensures error free operation.
  • Future proof to all foreseeable BWT standards by simple variation of treatment times during voyage.
  • Individual tanks can be treated in isolation and at times best suited to ship operations.
  • Re-oxygenation of water prior to discharge is quick and easy. This also restores the waters natural pH balance, ensuring zero environmental impact. ■



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