This instruction may differ in some nuances of operation specifically for your vessel, but in general it is suitable for most vessels. The ERMA First ballast system operates automatically, but still requires the attention of the operator and, in some cases, an engineer.
Important! This article is not detailed instructions for working with ERMA First BWTS; it describes the main points and some nuances. To fully familiarize yourself with the system, read the official instructions and watch the official video. It should also be said that this article is aimed at operators and engineers (ETOs) who already have some knowledge and understanding of working with the system.
Ballast pumping in
Briefly, the process of receiving ballast can be described as follows: water passes through a filter (40 microns), then through electrolysis with the conversion of sodium hypochlorite, and the already disinfected water enters the ballast tanks.
The active chlorine content is controlled by the TRO 1 unit (located on the E/R floor PS FWD) (your vessel may have a different location). Depending on the chlorine concentration (the permissible value of TRO 1 varies from 2Mg/L to 10Mg/L), the value of the current (electrolysis) changes.
If the active chlorine value at TRO 1 is higher or lower than the permissible value (less than 2Mg/L or more than 10 Mg/L), the monitoring system will notify you about this. Diaphragm pump No. 1 supplies water from the ballast line, immediately after electrolysis, to the TRO 1 unit.
Also, to receive ballast, you should select the position of the switches on the monitor - pump selection, system operating mode.
Switch positions (example): Mode – Ballast, Condition – normal, Fresh water operation – OFF, Secondary pumps – OFF.
Ballast pump out
To pump out ballast, the system switches to bypass and units TRO 1 and TRO 2 are activated.
Sodium bisulfite is used to neutralize active chlorine.
The dosing pump supplies the neutralizing reagent to the ballast line. TRO 1 measures the active chlorine level, while TRO 2 measures the chlorine level after neutralization (TRO 2 value should not exceed 0.1 Mg/L).
Switch positions (example): Mode – DeBallast, Condition – normal, DeBallast with – Pumps, Fresh water operation – OFF, Secondary pumps – OFF, Overboard Selection – Port O/B.
When changing the control to “Remote” (Ballast office control), the position of the switches does not need to be changed.
The system can also be configured to pump in fresh or semi-salt water into ballast tanks. For this purpose, seawater from AFT Peak is used. When the ballast pump starts, the Sea water pump will start, which will dilute fresh water to create active chlorine (salinity level must be at least 1.07 PSU).
Important! AFT Peak must be filled with seawater before ballasting operation (provided that the ballast will be pumped in fresh or semi-salt water).
Switch positions: Mode – Ballast, Condition – normal, Fresh water operation – ON, Secondary pumps – OFF.
Also, the switch on the Sea water pump panel should be in the AUTO position.
- Water from TRO 1 and TRO 2 flows by gravity into the TRO gravity drain tank. When the tank is filled to the float level, Diaphragm pump No. 3 will start and pump out the water back into the system. The pump will stop in Auto Modepump will stop in Auto Mode when the lower float is activated.
- Before the de-ballasting operation, the tank with sodium bisulfite should be mixed, since the reagent settles at the bottom. Start the pump (turn to MAN position) for 30 minutes and then turn the switch to AUTO.
- Back flushing filter is carried out using a suction pump installed next to it, as well as using a special drive installed inside the filter. The system will automatically flush the filter when the pressure difference is reached and the water from the filter will go overboard.
- Also, after receiving ballast through the system, upon going out to sea, you should restart the system to receive ballast (either on AFTpeak or on Slop Tank) for literally 5 minutes to manually wash the filter (Back-flushing filter manual).
Before starting the system, there must be no air present inside the TRO 1 tubes (one tube with buffer chlorine, the other with chlorine indicator). The tubes must be filled with the contents of the cans to which they are connected.
If they are dry or there are air bubbles, the pump will not be able to take the contents from the cans in the required quantity. Otherwise, the active chlorine value will be incorrect or below normal. To do this, there is a syringe in the TRO 2 panel.
Tube filling procedure:
- press the service button on the panel;
- wait until all the water comes out of the block (the hold signal lights up on the monitor);
- take out the can with chlorine indicator, unscrew it, take a syringe;
- take the contents from the can (literally a couple of milliliters) and fill the tube that goes into the measurement chamber;
- carry out a similar action with buffer chlorine;
- make sure that there is no air left in the tubes;
- screw the lids on the cans, put everything in its original position;
- press the service button;
- the system is ready for operation.
After the BWTS stops, water remains in the system. Due to the temperature difference, the pressure in the filter increases (can reach up to 9 kg on both pressure gauges).
The valves before and after the filter are closed, as they are controlled automatically. Based on this pressure, the interlock is triggered and turns off the transformer circuit breaker (in Engine Control Room).
Before starting the system again, reduce the pressure in the filter (there is a manual valve under the filter) and press the Reset button on the panel.
After this procedure, the system can be started.
If you have experience working with ERMA First BWTS, then share it in the comments to the article or in the official site groups on social networks. Thanks :)
Ballast Water Treatment System (BWTS) on a vessel is a crucial technology designed to manage and treat ballast water taken on board by ships to ensure it does not negatively impact marine ecosystems. Ballast water is used to stabilize vessels during transit by adjusting their weight and balance. However, it can contain various organisms, such as bacteria, viruses, and small marine animals, which, if discharged into a non-native environment, can become invasive species and cause significant ecological and economic damage.
Key Aspects of Ballast Water Treatment Systems (BWTS)
1. Purpose of BWTS
- Environmental Protection: Prevents the spread of invasive aquatic species that can disrupt local ecosystems and biodiversity.
- Regulatory Compliance: Ensures vessels comply with international regulations, such as the International Maritime Organization (IMO) Ballast Water Management Convention and U.S. Coast Guard (USCG) regulations.
2. Components of BWTS
- Filtration Units: Remove larger particles and organisms from the ballast water before treatment.
- Disinfection Systems: Utilize methods such as UV radiation, chemical treatment, or electrochlorination to kill or inactivate remaining microorganisms.
- Control and Monitoring Systems: Manage the operation of the BWTS and ensure compliance with treatment standards by monitoring the quality of treated water.
3. Types of Treatment Methods
Physical Treatment:
- Filtration: Mechanical filters remove larger organisms and debris.
- Ultraviolet (UV) Radiation: UV light inactivates microorganisms by damaging their DNA.
Chemical Treatment:
- Chlorination: Chlorine or other chemical agents disinfect the water.
- Ozonation: Ozone is used as a powerful oxidizing agent to kill microorganisms.
Electrochemical Treatment:
- Electrochlorination: Produces disinfectant chemicals through electrolysis of seawater.
4. Operational Steps of BWTS
- Ballast Water Intake: Water is taken on board through a filtration unit to remove larger organisms and particles.
- Primary Treatment: Initial disinfection (e.g., UV or chemical) to kill or inactivate smaller organisms.
- Ballast Water Storage: Treated water is stored in ballast tanks.
- Ballast Water Discharge: Before discharge, the water may undergo additional treatment to ensure it meets discharge standards.
5. Benefits of BWTS
- Protects Marine Ecosystems: Prevents the introduction of invasive species and preserves biodiversity.
- Regulatory Compliance: Helps shipowners comply with international and national ballast water management regulations, avoiding fines and operational delays.
- Operational Efficiency: Modern systems are designed to be efficient, ensuring minimal impact on vessel operations.
6. Challenges
- Installation Costs: Initial investment for BWTS installation can be high.
- Operational Complexity: Requires proper training for crew members to operate and maintain the system effectively.
- Maintenance: Regular maintenance is necessary to ensure the system functions correctly and remains compliant with regulations.
Ballast Water Treatment Systems (BWTS) are essential for modern maritime operations, ensuring that vessels manage their ballast water in an environmentally responsible manner. By using a combination of physical, chemical, and electrochemical treatment methods, BWTS effectively eliminates harmful organisms from ballast water, protecting marine ecosystems and complying with stringent international regulations.
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