GAC Group is a global provider of integrated shipping, logistics and marine services. It has recently developed the HullWiper, an environmentally friendly and diver-free solution for underwater hull cleaning. Managing director of GAC EnvironHull Simon Doran tells us how the new technology helps cruise ships save time, energy and the marine environment.

What is the GAC HullWiper and how is it applied?

Simon Doran: GAC EnvironHull’s HullWiper technology is a diver-free, cost-effective and environmentally friendly solution for underwater hull cleaning. HullWiper produces a fouling-free hull that significantly reduces fuel consumption and enhances long-term operating efficiency, while eliminating the necessity for expensive down time for cleaning operations. It is applied using the ‘Venturi effect’ created by the rotation of the cleaning discs.

The HullWiper remotely operated vehicle (ROV) is fitted with a light and camera, allowing its operator to control the cleaning process below the waterline from the support vessel. It is very easy to operate, and suitable for anyone with normal health and basic knowledge of monitoring a remotely operated machine, regardless of physical strength.

How does HullWiper help with preserving the environment?

HullWiper offers cruise ships a cleaning solution that enables them to meet their responsibilities for protecting the marine environment without disrupting their business. It collects marine fouling removed from hulls so that port water is not polluted. Captured residues are pumped into a filter unit and then deposited into dedicated drums onshore, which are collected by a locally approved environmental-waste disposal company.

In this way, HullWiper presents no threat to the sensitive marine environment. Unlike traditional brush cleaning, HullWiper leaves expensive antifouling surfaces intact and undamaged as no abrasives are used in the cleaning process. All fouling removed from the hull is disposed of in an environmentally friendly manner, protecting the marine environment from harm and the customer from potential fines or penalties.

GAC EnvironHull also works with environmental analysis and consulting professional AMT Environmental, to verify the effectiveness of HullWiper ROV’s filter system in purifying water captured during the cleaning before being discharged back to the sea. Data from biological analysis of post-filtration water reveals that the on-board filters are effective in filtering out the biofouling material removed from the vessels’ hulls during cleaning works. The concentrations of algae discharged are extremely low and likely in line with the natural rate of deposition from the biofouling growth on the ships’ hulls prior to cleaning while berthed in port. Chemical testing results also show that the chemical levels in water discharged from the filtration units are well below the required concentration for all parameters.

Alongside its environmental credentials, what other advantages does it offer over traditional cleaning methods such as brushes?

Cleaning is fast at 1,000-2,000m2 an hour compared with 200-400m2 an hour in traditional methods, and may be conducted during loading/unloading operations in port, eliminating the need for costly downtime. Also, no divers are involved, thus saving costs and reducing the risk to human life.

HullWiper improves vessel performance and fuel consumption efficiency. Compared with other methods presently on the market, it produces cost savings from 1t of fuel a day onwards, giving a return on the investment in cleaning costs of $3.50/m2.

How did you develop the product?

The HullWiper ROV design and features have been developed based on years of research and development with a view to providing the marine industry with a safe and environmentally friendly hull cleaning option. We consulted major shipping lines to determine what they thought would be the best development for existing hull cleaning services. From this, it became clear that ship-owners want solutions that deliver tangible operational results and enhance their corporate ‘green’ image.

Why is your partner FROG Marine Service so well qualified to deliver this service?

As a quality subsea service provider, FROG Marine Services was the obvious choice in Scandinavia to deliver this service. It provides expert services specialising in the highest standards of performance, safety and qualified personnel for all underwater solutions. FROG Marine is ideally placed in close proximity to all major cruise terminals in Scandinavia, and can service and respond to subsea requirements at short notice.