EXHAUST SCRUBBERS IN SHIPS

Subject: Economy

Context :Thanks to exhaust scrubbers, while ships are polluting the air less, their water-pollution footprint is rising.

Concept :

On January 1, 2020, the IMO, a UN body, started the enforcement of a rule banning sulphur-heavy fuel.
Since sulphur-light fuel can be very expensive, it allowed ships to install exhaust scrubbers that use high-volume, high-speed, water spray to absorbs pollutants from the exhaust.
Following the adoption, exhaust scrubbers have become one of the most preferred ways of reducing sulphur exhaust as they ‘scrub’ pollutants out of emissions.

There are two types of exhaust scrubbers- open and closed.

open-loop ones that dumps the scrubber wastewater into the sea/at the port and closed loop ones that treat the wastewater before dumping.
A the time of adopting the new norms, it was hoped that more ships will get fitted with closed-loop scrubber systems.
Both kinds of scrubbers have led to the dumping of 10 gigatons of scrubber wastewater containing dangerous pollutants and toxic chemicals, including carcinogenic hydrocarbons.
This has endangered not just sensitive marine ecosystems along the most popular sea routes, but also threatens human health through seafood-consumption.