Sea Sentry – DNV GL Compliant Wash Water Monitor for Ship Exhaust Gas Cleaning Systems
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.
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.
Breaking News: Fully Compliant Solution: Statement of Compliance from DNV GL.
- Confirm wash water from ship exhaust gas cleaning systems is within regulatory limits.
- Systems suitable for both new ship and retrofit installations.
- Compatible with Open Loop, Closed Loop and Hybrid systems.
- Ensures the environment is protected from contamination in exhaust gas scrubber wash water discharge.
- Fuly compliant with IMO MEPC 259(68), with Statement of Compliance from DNV GL
- Turnkey solution to monitor Polycyclic Aromatic Hydrocarbon (PAHphe eq), Turbidity, Temperature and pH
- PAHphe eq fluorescence is automatically corrected for turbidity, UV absorbance & temperature
- Continuous real-time monitoring of wash water discharge
- Ethernet interface (Modbus TCP/IP) and 4-20 mA analogue outputs to main control system.
- Air purge anti-fouling system
- Automatic monitoring of cleanliness of optical sensors' windows.
- Flexible configurations suitable for retrofits and new ship builds
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 to the local and wider environment
To make ships greener, and prevent pollution of the marine environment, the IMO has established a number of new regulations through its Marine Environment Protection Committee (MEPC). In 2005, the MEPC introduced regulations for the prevention of air pollution under Annex VI of the Marpol Convention. Under the new rules, ships operating both globally and in Emission Control Areas (ECAs) must reduce NOx, SOx and particulate emissions.
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 and damage the environment.
How does it work?
In 2005, the MEPC introduced regulations for the prevention of air pollution under Annex VI of the Marpol Convention. Under these new rules, ships operating both globally and within ECAs must reduce NOx, SOx and particulate emissions, to reduce environmental impact of shipping. With the global sulphur limit dropping to 0.5% in 2020, the shipping industry will need to implement strategies to meet this target. A relatively low cost solution is to install an exhaust gas cleaning system to reduce emissions.
Wet scrubbers remove a wide range of pollutants from exhaust gas, but one of the principle challenges associated with wet scrubbing is handling the wash water discharge, which contains Polycyclic Aromatic Hydrocarbons (PAHs) that are harmful to the environment and human health. Therefore, this wash water needs to be monitored for PAHs, alongside other water quality parameters including pH and Turbidity, prior to being discharged into the ocean.
Sea Sentry is a turnkey solution to ensure that the wash water discharged from exhaust gas cleaning systems (EGCS) is compliant with the global regulations on discharge. Using CTG’s specifically designed and proven sensor technology, it monitors both the sensor inlet and outlet of wet exhaust gas scrubber systems.
Sea Sentry measures PAH fluorescence (reported in μg/L phenanthrene equivalence, PAHphe eq),Turbidity (to ISO 7027: 1999 International Standard),Temperature and pH. It also incorporates an integral pump, de-bubbler, pressure relief valves and a flow meter. PAHphe eq is corrected for turbidity, UV absorbance and temperature. This enables Sea Sentry to monitor open-loop, closed-loop and hybrid scrubber systems.
Sea Sentry has a Statement of Compliance from DNV GL and is fully compliant with IMO MEPC 259(68). A touch screen display provides a flexible user interface and data is relayed to a main control system via an Ethernet connection and 4-20 mA analogue outputs.
A typical system includes:
- Electronics Unit
- Air-purge system
- Integral circulation pump
- pH/Temperature Sensor
- PAHphe eq/Transmissometer Sensor
- Turbidity Sensor
- Flow Meter
Each cabinet can be configured and expanded to meet particular customer requirements. Additional sensors may be installed as required and mechanical interfaces selected to meet specific installations.
DNV GL Approval
|The Sea Sentry has been tested in accordance with the requirements of Resolution MEPC. 259(68) in respect of washwater monitoring and received a Statement of Compliance from DNV GL. The Statement of Compliance has been achieved through vigilant testing by DNV GL to ensure that Sea Sentry meets their requirements regarding calibration range, drift, accuracy, precision and noise, as well as the influence of turbidity, UV absorbance, temperature and salinity. The effectiveness of CTG’s mitigation method against air bubbles and the use of the supplied test kit to calibrate optical sensors has also been demonstrated to the satisfaction of DNV GL. The CTG systems have been successfully installed and used on vessels around the world and ship owners can now confidently monitor the efficacy of their scrubber systems and ensure that they are within regulations.|
Typical System Specifications
Universal 85 - 264 VAC, 45 - 65 Hz,90 - 350 VDC
|Dimensions||1300 (H) x 600 (W) x 300 mm (D)|
|Operating pressure||Up to 4.0 bar|
|Ambient operating temp||0 - 50 ºC|
|Sample flow||3 - 40 L/min|
|PAH range||0 - 4500 µg/L Phenanthrene equivalence (LOD*: 0.07 μg/L), (Turbidity, UV absorbance and temperature corrected)|
|Turbidity range||0 - 1000 FNU (LOD*: 0.15 FNU)|
|pH range||0 - 12 (LOD*: 0.01)|
|Temperature range||0 - 50 °C (LOD*: 0.13 °C)|
|Absorbance range||0 - 3.500 cm-1 (LOD*: 0.002 cm-1)|
|System outputs||Modbus TCP/IP (RJ45) and 4-20 mA Analogue Outputs|
|Display/user interface||10.1” Projective capacitive touchscreen interface 1280 x 800 resolution toughened glass screen|
|Sample inlet/outlet||Flange, DIN32 PN10 (Alternatives on request)|
|Sensors flow-line, Electronics enclosure|
|IP rating||Electronics enclosure IP65|
|Air-purge pressure||5.0 - 5.5 bar|
|Pressure relief valve||6.0 bar (vented to the bilge)|
DNV GL Statement of Compliance
Established over 50 years ago Chelsea technologies Group specialises in the design, development and manufacture of a range of sensors and systems for the marine, maritime, environmental and defence markets. Sea Sentry is based on our high precision PAH and turbidity sensors, which have a proven record in a wide range of monitoring systems.
Sea Sentry and FastBallast (our real-time sensor for monitoring ballast water discharges in accordance with IMO and USCG regulations), provide ship operators with the confidence that they are able to demonstrate compliance with increasingly stringent environmental directives.
|DNV GL Fully Compliant Solution:
The Sea Sentry has been tested in accordance with the requirements of Resolution MEPC. 259(68) in respect of washwater monitoring and received a Statement of Compliance from DNV GL.