After carriage of the bulk cargoes, the holds must always be swept before any attempt is made to wash. This will reduce the effects of unwanted cargo residues building up in hold bilges and hindering the process of pumping away the washing water.
Fig: Washing down hold
Old dunnage is not to be retained onboard unless specifically requested for by the Charterers. When disposing of waste materials, attention must be drawn to the International Regulations concerning the disposal of garbage at sea. It must be stressed that on no account are plastics to be thrown overboard into the sea at any time.
Consideration must also be given to the type of residues involved; some heavy cargoes may lie in bilge lines and may not be pumped away. There is also the possibility of damage to pumps, valves and valve seals. Washing after carriage of this type of cargo should involve the use of a portable salvage pump to remove washing water rather than using the hold bilge pump. For cement cargoes, the bilge pumping system must not be used as any water left lying in the pipeline will hold cement in suspension and will eventually harden in the pipelines, valves and pumps.
If there is no other facility available to you other than the hold bilge pumping system when dealing with cargoes such as the above, a constant and plentiful supply of clean seawater must be supplied to the bilges during pumping to dilute the washing water as much as possible and prevent a build up of residues. Even when using this method it may be necessary to frequently stop washing and pump clean sea water through the system to reduce build up of residues before resuming the washing operation.
Bilge strainers must never be removed during washing of holds and pumping of waste water. If the strainers are blocked, the washing and pumping operations must be stopped and the strainers thoroughly cleaned before resuming the operation. This must be done as frequently as necessary to ensure as little solids as possible are passing through the bilge lines.
On completion of sea water washing of holds, a fresh water rinse must always be carried out. Salt deposits may contaminate cargo, and due to the corrosive nature of salt, will damage coating, fittings and steelwork. An ample supply of fresh water must always be obtained in anticipation of this operation, although it is often surprising how little fresh water is required to perform this task. Ideally it can be carried out before the hold is allowed to dry, after sea water washing, thus preventing salt deposits to accumulating and so making the job much simpler.
The conventional bulk carrier has a box construction with large frames, usually smooth hopper sides fore, aft, port and starboard. The underdeck and coaming frames are situated high up and are often impossible to get to physically, as are the high ship side frames. These frames can retain traces of old cargo: corrosion, scale and residues of previous cargo can collect and fall, and contaminate the next cargo.
Some bulk carriers, including many smaller coastal-type ships, are built with box holds. This means that the hold sides are boxed in with smooth steel sides, making discharge and cleaning much easier as there are no frames. These box holds, however, often have adjacent ballast tanks that may be prone to water leakage through grab damage.
The ship structure, including ladder rails, stanchions, rungs and pipe protection fittings, can become damaged during discharge. Any such damage should be noted and repaired on a continuing basis so that steel fittings torn from the ships structure by grabs or bulldozers do not contribute to cargo contamination. This can also result in damage claims to shoreside discharging and conveyor machinery and equipment. The sheer size of the holds is a factor that often prevents a good hold-cleaning operation from being performed.
In addition, the following can cause contamination of the next cargo:
Opening hatches at sea for cleaning
- grab damage to steel fittings and protection brackets
- loose bulkhead or tank top rust scale increased by damage from grabs or cargo
- grab damage to hold ladders or hold fittings
- tank top and ballast side tank integrity jeopardised by grab damage
- tank top, double bottom and side tank access lids damaged by bulldozers and grabs
To avoid damages to the vessels equipment, a risk assessment must be completed whenever the cargo hold hatches are required to be opened at sea for the purpose of cleaning and preparation. The risk assessment should include requirements to monitor weather conditions, maximum number of hatches to be open at any given time and vessels inspected movement during the cleaning operation.
For the avoidance of doubt, hatches must not be opened when the ship is rolling and must not remain open overnight.
The Chief Officer is to ensure that locking pins are inserted when the hatches are open. In addition to the locking pins, hatches must be secured using wire strops and tensioning devices.
Care is to be taken in selecting the point of attachment on the underside of the hatch. This point must be sufficiently well inboard so as not to tip the cover on tensioning down to a strong point on the deck.
Washing of hatch covers undersides
Hold washing operations are often carried out with the vessel's hatch covers open, such as when the vessel is lying at anchor. On these occasions, it is important to ensure that the hatch cover undersides are not forgotten. Frames and drain channels are to be well swept and washed out. Any small spaces which are missed may well contain cargo residues which would then contaminate a clean hold while closing the hatch. Similar attention is to be given to the hold accesses and ventilation hatches.
Fresh water rinsing
In certain circumstances it will be necessary to rinse the cargo hold with fresh water to remove any salt deposits. If there is any doubt the Master is to seek advice from the relevant Management Office.
In the final preparation of the cargo holds, it must be remembered that drying time may be greatly reduced by the use of the vessel's forced draught ventilation system, if fitted. In all cases, ventilation for drying purposes must be altered according to the prevailing weather conditions, sea temperature and the temperature of ballast water in adjacent ballast tanks, all of which may cause either condensation or sweat.
Cleaning of hold fixed fire fighting installation
The fixed fire fighting installation in the hold is to be inspected for damage. The system is to be blown through with air to ensure that all nozzles are clear.
Cleaning of hold bilges
Hold bilges must always be cleaned out thoroughly and bilge suctions tested before loading another bulk cargo. Bilge covers are to be wrapped in burlap, replaced in position and secured.
Chief officers inspection
Fig: Hold of a bulk carrier that is grain clean and ready to load
The Chief Officer must always carry out a full and final inspection of all cargo holds before presenting them for shipper's final approval and acceptance, to ensure that all cleaning work has been carried out as per his instructions and to his satisfaction, and that he is satisfied that the cargo holds are in a suitable condition for the carriage of the next commodity and presentation to the shippers.
The relevant Management Office must be advised immediately of any expected problem with regard to the holds, passing inspection.
For the carriage of grain cargoes, it is sometimes a requirement that cargo holds be fumigated before loading to irradiate any insects which may have been present. When selecting the type of fumigation to be used, always consult the local Authority regulations, your agent or hold inspectors who will be able to give you advice on this, as many Authorities require use of a specific fumigant.
After fumigation, hatch covers, accesses and vents must not be opened again until the final inspection by shore inspectors. Care and attention must be paid to matters of personal safety when using any fumigant. Reference is to be made to the appropriate Reference publication.
Our detail pages illustrated many safety aspects of Bulk carrier
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Cargo hold cleaning recommended chemicals
Various Cargo Hold Cleaning Kits & chemical washing technics
Cargo hold Swept cleaning, Washing down, Use of chemicals, Limewashing & Drying holds technics
Cargo hold cleaning problem and related guideline
Hold cleaning in bulk carriers- Preparation for grain loading
Methods of cargo hold cleaning
Cargo hold maintenance guideline
Hold preparation checklist -Cleanliness/preparation, additional measures
Cargo holds readinesss, maintenance requirement, preventing stevedore damages & safety aspects
Cargo hold inspection -Reasons for failing hold inspections
Chief officers final inspection prior cargo hold survey
Maintenance procedure for mechanical steel hatch covers
- Holds rejected for not being cleaned to grain standards
- Cargo hold cleaning recommended chemicals
- Various Cargo Hold Cleaning Kits & chemical washing technics
- Cargo hold Swept cleaning, Washing down, Use of chemicals, Limewashing & Drying holds technics
- Cargo hold cleaning problem and related guideline
- Hold cleaning in bulk carriers- Preparation for grain loading
- Cargo hold maintenance guideline
- Hold preparation checklist -Cleanliness/preparation, additional measures
- Cargo holds readinesss, maintenance requirement, preventing stevedore damages & safety aspects
- Cargo hold inspection -Reasons for failing hold inspections
- Chief officers final inspection prior cargo hold survey
- Garbage management plan for bulk carriers
Operation of sea going bulk carriers involved numerous hazards . Careful planning and exercising due caution for all critical shipboard matters are important . This site is a quick reference to international shipping community with guidance and information on the loading and discharging of modern bulk carriers so as to remain within the limitations as specified by the classification society.
It is vital to reduce the likelihood of over-stressing the ship's structure and also complying with all essential safety measures for a safe passage at sea. Our detail pages contain various bulk carrier related topics that might be useful for people working on board and those who working ashore in the terminal. For any remarks please Contact us
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