Carnival Corporation, the world’s largest cruise shipping company, has retrofitted 77 % of its fleet with exhaust gas cleaning systems, commonly known as scrubbers, splashing a total of $500 million on installations to date.
The cruise major launched scrubber installations on board its ships back in 2013, when the technology was in its early days of development, helping further develop the solution to fit constricted places on ships.
The company wants to install scrubbers across its global fleet.
Carnival Corporation has opted for open-loop systems that use a seawater spray for removing sulphur from engine exhaust, converting it to sulphates before returning the seawater to the ocean.
“The seawater is monitored by pH, PAH and turbidity sensors through this process to ensure that it meets or exceeds the IMO required standards before returning to the ocean,” Carnival said in its sustainability report for 2019.
“A further filtration process while in port ensures a seawater quality meeting other applicable environmental standards for operations. “
The company claims that extensive independent testing has shown that the scrubbers outperform low-sulphur fuel alternatives such as marine gas oil (MGO) in terms of overall cleaner air emissions and no negative environmental impact on oceans and seas.
Specifically, in March 2019 the company released the Carnival/DNVGL 2018 Wash Water Assessment. The four-year scientific wash water study collected wash water samples from 53 Carnival ships, conducted lab analyses on each sample for 54 different parameters including PAHs and metals, and partnered with DNV GL to evaluate and compare the results to major national and international water quality standards.
“The study demonstrated that the AAQS wash water samples were well below the limits set by several major national and international land-based water quality standards up to and including the World Health Organization (WHO) standards for drinking water,” Carnival said.
Carnival has also started to install a catalytic reactor on the engine exhaust to reduce particulate matter (PM) even before the exhaust reaches the scrubber tower. As disclosed, the company’s standard scrubber system removes 98% of sulfur (in the form of SOǍ) and up to 60-90% of the particulate matter, including elemental and organic and black carbon.
Aside from scrubbers, Carnival is a strong supporter of LNG as fuel, having already added two ships powered by LNG to its fleet, Costa Smeralda and AIDAnova.
The company has an additional nine next-generation cruise ships on order that will also be powered by LNG, both in port and on the open sea, with expected deliveries between 2020-2025.
Other highlights: