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Covid-19 shipping disruptions: Solve biofouling with pasteurisation

Dilong Goh for The Straits Times

Many vessels were stalled earlier this year when the coronavirus pandemic halted global shipping traffic. Even months later, we are still seeing this issue of ships being stalled across the globe.

As The Straits Times reported, a 22,000-tonne tanker meant for voyage between Singapore and Manila has not stepped on land in 10 months.

Researchers Stefan Huebner and Anthony Medrano pointed out in an article published in this newspaper that shipping disruptions lead to the spread of harmful alien species. Where an economic threat arose from disrupted supply chains, environmental threats in the form of biofouling became a heightened concern as a result of idle ships on Singapore waters. 

Biofouling is the introduction of alien bacteria and species into native water bodies, which can stress and alter local ecosystems that may consequently lead to biodiversity loss. It may also lead to public health concerns should there be species with disease-spreading capabilities.

The introduction of alien invasive species (AIS) was what led to the 1991 cholera outbreak in South America.

This was facilitated by the transportation of an Asian strain of cholera to Peru’s coastal waters by ballast water. The gravity of the consequences that AIS can bring demands the  shipping industry to seriously look into its ballast water management efforts.

The International Maritime Organization (IMO) has since long recognised the extent of the biofouling problem. It signed the Ballast Water Management Convention in 2004, made effective in 2017, which mandates signatory flag state to ensure that ships comply with standards and procedures for the management and control of ships’ ballast water and sediments. 

Ballast water refers to water held in the ballast tanks of ships. This is meant to provide stability and maneuverability with respect to the load carried on board. 

One ballast water management system (BWMS) technology used as a solution to biofouling is pasteurisation. It is a relatively new alternative in the BWMS industry but holds strong potential. Unlike the conventional methods such as filters and UV solutions, pasteurisation does not require additional equipment or chemicals to be injected into the water. This means that there will be little to no occurrences of chemical leaks into local water bodies. 

Moreover, conventional solutions require more maintenance than pasteurisation: filters need to be consistently maintained and replaced to prevent clogging, and ultraviolet bulbs are vulnerable to breakage. UV performance is also easily compromised by water turbidity whereby water loses its transparency due to the presence of suspended particulates. Whereas, pasteurisation technology will not face these disruptions.

The onus is thus put on ship owners to decide on a BWMS solution that is able to consistently deliver according to the Convention’s standards.

Hasty adoptions of common technology solutions in a niche and still-developing BWMS market may result in inconsistencies in meeting standards thereby negating the Convention’s protection efforts over local water bodies.  

Given its smart efficiency, flexibility and simplicity, the pasteurisation technique holds great potential to be the preferred method of ballast water management. One company that has embraced this innovative technology is Danish company, Bawat A/S, which is the first to receive a United States Coast Guard Type Approval for its new heat pasteurisation-based BWMS technology.

Efforts to protect our marine diversity should not just be a top-down approach via regulations imposed by the IMO or local laws. There should be greater urgency from ship owners to carefully assess the performance of their chosen ballast water systems to ensure the protection of our waters.

Dilong Goh is the Managing Director of GIANTECH Engineering Pte Ltd,  Asia’s leading marine service engineering company specialising in the life-cycle management of marine equipment. GIANTECH was named one of Singapore’s fastest growing companies in 2019 by The Straits Times.