Our organization has been committed to minimize pollution ever since obtaining the regulatory and statutory clearances. A clear-cut framework to curb pollution has been formulated and a dedicated team is working on 24-hour basis to achieve the same. Activities such as practicing a mechanized dust suppression system, water sprinkling on roads, proper tarpaulin covering, truck tyre wash system and running an automated dry fog system in the Hoppers during discharge are being implemented effectively.
Our organization has identified the sources of pollution through aspect-impact identification mainly from the operations that are being taking place. The main operation being handling of coal involves generation of particulate matter, similarly the transport of coal involves generation of fugitive emissions. Effluent is generated from the domestic activities, likewise hazardous wastes such as lubes and used oils are generated from the machinery and vehicles. Thus, based on the type of activities sources of pollution have been identified and quantified and based on which a stringent environmental management plan has been formulated.
One example is the installation of automated dry fog system in the hoppers. The major advantage of using this mechanism is when the cargo is being unloaded by the grab from the ship into the hopper, the dry fog system in an automated manner starts functioning, thereby suppressing the particulate matter pollution
The conveyance of coal is carried by a completely mechanized system and is fully covered with cladding sheet thereby reducing the pollution.
PLC operated Mechanized dust suppression system is one such state-of-the-art system which comprises of 100 sprinklers in which 94 are mechanized and 6 are manual covering the entire stack yard. They function all along the yard by sprinkling water up to a height of 10 to 12 meters and is operational with 180-degree rotation.
MDSS is operated through PLC at open coal stack yard ensuring coal heaps remains wet at all times. This system is envisaged to control the dust generated in the stockpile area. Total of 100 sprinklers are installed in stack yard for ensuring wetness of coal heaps and internal roads. Water at a pressure of about 5-6 bar is sprinkled over the stockpile area. The sprinklers are of swiveling type. The operation of the sprinklers is automatic by means of solenoid valves controlled by PLC from Central Control Room. When these sprinklers are operated, the dust control is achieved by the agglomeration of dust particles with finely atomized water droplets equal to / close to / larger than the dust particles as the case may be, the collision between the water droplets and dust particles plays an important role in the process of agglomeration and heavier mass thus formed settles down to the ground. Water stored in a settling pond, which shall be supplied to the spray headers by a pumping system. Two sprinklers at a time are operated sequentially to control any dust generation due to winds.
DFDSS is provided at Ship Unloader hopper, Transfer houses, Wagon Loading Station. This system uses nozzles by injecting mixture of air and water at high pressure for dust suppression. The fog system uses fine nozzles and high water pressure to produce droplets size of 50–200 µm.
Mist Cannon is a water mist based dust control system with a throw range of up to 15 meters under ideal conditions. The dust suppression via mist cannon systems in which water and dust particles collide to form agglomerates by the addition of micron size water droplets to dust and dust becomes too heavy to remain airborne and they settle.
Truck Tyre Washing System is one of its kind installed for cleaning the tyres of trucks when they are leaving our terminal, to control and eliminate the pollution on roads. This is an automated permanent fixed drive through installation and can handle 25 trucks per hour. The advantage of drive-through system is that the vehicle does not have to stop for cleaning. As the vehicle passes the magnetic-sensor or photo-sensor at the entrance, the washing process is triggered. During the slow passage (10 kmph speed) through the wash platform, the vehicle’s tyres, wheel wells and mud flaps are cleaned by water sprayed from many strategically placed nozzles. The mud coming out of washed water is settled at the bottom which can be removed manually at certain stage and water is routed to settling pond for reuse.