We are currently supplying wash water monitoring systems to the marine industry’s leading provider of Exhaust Gas Cleaning Systems and our systems are now installed in over 100 vessels," said CTG's Stephanie Lavelle.
Ship exhaust gas emissions from marine diesel engines release harmful gases and particulate matter into the atmosphere. Of particular concern are emissions comprising of NOX, SOx and hydrocarbon particulates, together with CO2, which are detrimental to human health and the environment. To make ships greener and prevent pollution, the IMO has established a number of new regulations to reduce emissions, and continues to tighten regulations on sulphur content in marine fuel in order to reduce sulphur dioxide emissions from ships. When the global limit drops to 0.5% in 2020, the shipping industry will face a difficult decision – switch to expensive low sulphur fuel (with an economic impact estimated at tens of billions annually) or to implement relatively lower cost exhaust gas cleaning systems.
One method of doing this is to clean emissions before release using an exhaust gas cleaning system. All varieties of wet scrubber systems use wash water which must be monitored at all times to avoid discharges that may exceed regulations & damage the environment. CTG's Sea Sentry provides a wash water monitoring system - it monitors both the sensor inlet and outlet of wet exhaust gas scrubber systems. It is a turnkey solution which measures Polycyclic Aromatic Hydrocarbon, Turbidity (to ISO 7027: 1999), Temperature and pH. It incorporates an integral pump, de-bubbler, pressure relief valves and a flow meter.
In addition to SOx, emissions from marine diesel fuels contain particulate matter and polycyclic aromatic hydrocarbons (PAHs). Wet scrubbers clean a wide range of pollutants out of the gas, including SOx and PAHs. One of the principle challenges associated with wet scrubbing is handling the wash water discharge since PAHs are harmful to both people and the environment. Therefore, after scrubbing, the wash water is treated and monitored for PAHs prior to being discharged in the sea. This reduces the possibility of pollution shift from air to water, which would otherwise negate the benefits of exhaust gas cleaning.
Open and Closed Loop Systems
CTG has direct experience of compliance and the high standards demanded by regulators. CTG’s Sea Sentry scrubber wash water monitoring system has the capability to accurately measure the required parameters of water in both open loop and closed loop scrubbers, providing accurate data that proves compliance with wash water regulations.
CTG's Sea Sentry provides a fully autonomous wash water monitoring system which monitors both the water inlet and outlet of wet exhaust gas scrubber systems. The system analyses wash water to ensure that it is compliant with environmental regulations which reduce potentially high levels of contamination in exhaust gas scrubber wash water discharge.
Unique challenges of Closed Loop Systems
Closed loop scrubber systems present a unique challenge when monitoring water as the recirculation process darkens the water, making it difficult to obtain an accurate PAH measurement. It is by adapting the monitoring process to not only measure the turbidity and absorbance levels, but to apply these values as a correction to the PAH measurements, that accurate readings can be taken. If the readings are not accurate, owners are risking significant fines or detention.
It is essential that crews have a thorough understanding of the regulations, monitoring procedures, and the analysis and interpretation of the data. CTG works closely with shipowners, the leading global scrubber manufacturers and the Exhaust Gas Cleaning System Association to provide operators with the knowledge and expertise they need to operate with the highest level of confidence in their system and in proving compliance under the IMO criteria. Sea Sentry is certified by DNV-GL and ClassNK and is the gold standard solution which measures the polycyclic aromatic hydrocarbon, absorbance, turbidity (to ISO 7027: 1999), temperature and pH of scrubber washwater.
The route to 2020 compliance is complicated and there is no “one size fits all” option. Ship owners and operators must weigh up the costs and benefits associated with each option although there is increasing sentiment that scrubbers will have an important role to play. But with increasing environmental regulation, accurate monitoring will be essential to provide operators with confidence in the reliability and accuracy of their systems to remain compliant and enjoy continued access to markets.