how to clean marine tanks/طرق تنظيف الخزانات البحرية للمراكب

how to clean marine tanks
by
general.dr
bahaa badr

technolab el-bahaa group

Print this article

The deck of a Very Large Crude Carrier, seen from the bow
Grain, crude oil, iron pellets and chemicals are only a few of the products carried in the tanks of a tanker ship.

Crude oil tanks can only be washed with crude oil, under the provisions of the 1978 Treaty to Prevent Marine Pollution which were enacted in 1999, but the tanks used for other bulk cargoes that travel by sea are cleaned with fresh water which then must be removed from the ship.

The process is largely automated and uses the ship's systems, but since the cleaning water cannot be discharged at sea, a service industry has developed ashore.

Instructions

Things You'll Need

Centrifugal pumps 2 inch water hoses with cam lock ends Personal Flotation Device for each worker (required by law) Safety cones or other markers No Entry Zone signs

1

Determine what product was last carried in the tank.

Usually, this information will be available from the ship's first officer or master.

This is essential since the vapors lingering in the tanks after the discharge of some products, like benzene or acetylene, can be harmful or fatal. Others, such as alcohol or hydrogen, are explosive. Secure a Confined Space Entry Permit from the master.

2

Unbolt the man-hatch access cover to the first tank with an adjustable wrench if physical entry to the tank for inspection and cleaning is necessary or if gas-freeing the tanks and testing by a marine chemist is required.

Remove the hatch cover from the opening by sliding the cover to the side. Mark off the area around the hatch as a "No Entry" zone.

3

Allow the tank to air for 5 minutes.

If a marine chemist's report of a "gas free status" is required by shipping company policy, yard policy, local ordinance or law, take no further action until the report is received.

4

If a marine chemist's report is not required and if the use of a flame safety lamp is approved, inspect and prepare the flame safety lamp.

Test the atmosphere in the tank by slowly lowering the flame safety lamp to the bottom of the tank then slowing retrieving it while observing its flame.

If the flame changes in size or color, or goes out completely, notify your supervisor and await instructions.

5

Move the hoses, pumps and associated equipment to the vessel only after all tanks are determined to be safe to enter.

Mark any hoses or electrical cords laying on deck with Trip Hazard warning signs.

6

Connect the extraction hoses to the suction side of the extraction pumps to remove water from the tanks.

Connect the discharge side of the extraction pumps to the hose leading to the shore-based recovery system.

Connect hoses from the discharge side of the supply pumps to the Butterworth machines's cam lock deck connectors, usually located near the innage and ullage holes (used to check tank levels), and connect the suction side of the supply pumps to the shore water supply.

7

Start the extraction pumps and the Butterworth machines.

The Butterworth machines are double-ended spray nozzles, one per tank, rotating through 360 degrees vertically and 360 degrees horizontally to clean the tank interior.

Continue the cleaning operation as instructed, then secure the Butterworth machines.

Continue pumping out the cleaning water.

When instructed, secure the pumps, close any hatches opened, move to the next tank and repeat the process.

When all tanks are completed, remove all hoses, pumps and associated equipment to shore.

» طرق تنظيف الخزانات النفطية
» صور مراحل تنظيف الخزانات المختلفة
» صور مراحل تنظيف الخزانات المختلفة2
» اهمال تنظيف الخزانات والمرض
» Cleaning In The Food Industry/ تنظيف الخزانات فى الصناعات الغذائية