IMSBC ( International Maritime Solid Bulk Cargoes Code)

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Solid bulk cargoes consist of solid in particle or granular form, Generally homogeneous in composition, Loaded directly in hold without any packing.

The IMSBC Code was adopted on 4 December 2008, by resolution MSC.268(85), and entered into force on 1 January 2011, from which date it was made mandatory under the provisions of the SOLAS Convention. Since then, the Code has been amended.

AIM OF IMSBC

  • Highlights danger associated with the shipment of bulk cargoes.
  • Give guidance on procedure to be adopted.
  • List tropical materials currently being shipped in bulk.
  • Describes test procedure to determine various characteristics of bulk cargos.

IMPORTANT DEFINITIONS

  1. Angle of repose – Is the angle between the horizontal plane and the cone shape obtained when bulk cargo is loaded on this plane.
  2. ConcentratesOre concentrate, dressed ore or simply concentrate is the product generally produced by metal ore mines. The raw ore is usually ground finely in various comminution operations and gangue (waste) is removed, thus concentrating the metal component. The concentrate is then transported to various physical or chemical processes called hydrometallurgy, pyrometallurgy smelters, and electrometallurgy where it is used to produce useful metals.
  3. Moisture Migration – Concentrates have moisture enriched in them. At sea due to vibration and ships motion, the cargo settles and consolidates, Displacing the water. Thus a flow state may develop, When masses lose its internal shear strength, resulting in wet shift of cargo.
  4. Moisture content – Is the percentage weight of water contained in total weight of the sample.
  5. Flow moisture point (FMP)- Is the percentage moisture content at which flow state may develop.
  6. Transportable Moisture Limit – Is the maximum moisture content of a concentrate considered safe for carriage by a general cargo vessel.
    • It is around 90% of FMP.

PRECAUTIONS WHEN CARRYING HIGH DENSITY CARGO

  1. High density cargoes are those that have a stowage factor less than 0.56m3/Tonne.
  2. Generally cargo vessel complete loading with stowage factor of 1.39 to 1.67m3/Tonne.
  3. One danger when loading high density cargo is because the hold looks empty after loading high density cargo due to negligence one might load more cargo. So at any time load density of the deck must not be exceeded.
  4. Hold wise distribution of high density cargo by weight should not differ appreciably from that of general cargo. This prevents excessive Shear and force and bending moments.
  5. Maximum quantity of cargo loaded in any hold should not exceed 0.9 * L * B * D where L is Length of hold in m, B is Average Breadth in m and D is Summer load draft in m.
  6. Where cargo is trimmed or partially traimmed, The height of cargo peak above the tank top should not exceed 1.1 * D * SF.
  7. If the cargo is trimmed, 20% increase over { Maximum quantity of cargo loaded in any hold should not exceed 0.9 * L * B * D where L is Length of hold in m, B is Average Breadth in m and D is Summer load draft in m.}
  8. If shaft tunnel passes through the hold 10% increase over the points 5,6,7 .

PRECAUTIONS WHEN CARRYING BULK CARGO

Link to the article is pasted below and you must go through it, very important for 2MFG.

Additional precautions for bulk cargo and high density cargo.

GENERAL PRECAUTION WHEN LOADING BULK CARGO

  • Inspect hold for suitability prior loading.
  • Ensure the hold is clean, Dry, Free from any stain.
  • Ensure that bilge wells, Strainer plates, sounding pipe, bilge suction etc are tasted and found satisfactory.
  • Deck machinery should be protected from dust while loading.
  • Air condition to be on re-circulation.
  • Sound bilges before and after loading.
  • While loading high density cargo the cargo should not fall directly into the empty hold as the tank top may get damaged.
  • Bulk cargoes are loaded at a high rate so de ballasting, loading sequence, trim, list, gangway, moorings must be attended.
  • Dust created by certain cargoes may constitute a health as well as an explosion hazard. precautions to be used like use of dust mask.
  • Bulk material may cause oxygen depletion, Entry of personnel should be in accordance with enclosed space entry procedure and permit.
  • While loading and discharging all appropriate national and international safety regulations are to be observed.

CONCENTRATES

Hazards of concentrates

  • High Density
  • Dry shift (Below TML)
  • Wet shift (Above TML)
  • Spontaneous combustion

Precautions when carrying concentrates

  • General cargo ship can carry concentrates only when cargo is at or below TML. Otherwise special subdivisions are fitted to reduce the shift of cargo (With prior approval from administration).
  • Wet and liquid cargo should not be loaded in same compartment as concentrates.
  • Cargo work should not be carried out during rain.
  • Entry of Water, Rain, Spray should be prevented.
  • To reduce the effect of oxidation, cargo should be trimmed.
  • In case stock pile is exposed to precipitation then test samples must be taken just prior to loading.
  • When delivery of cargo is by road, rail, Barge where entry of water is suspected, Then random check should be made of one in five vehicles.
  • Shipper must present certificate from competent labs stating the FML, TML, MC.

COAL

HAZARD ASSOCIATED WITH COAL

Spontaneous heating – coal is very liable to spontaneous heating freshly mixed coal absorbs oxygen forming peroxide which breaks up into carbon monoxide and carbon dioxide this is an exothermic reaction and the heat produced cause further oxidation and more heat.

Emission of Methane – Coal emits methane Gas particularly immediately after loading and when newly work or freshly broken methane is a flammable gas and when mixed with air forms an explosive mixture. It is lighter than air and therefore accumulates in upper reason of the hold and other spaces.

Corrosion – pond coal is the term given to coal left over from earlier mining which has been dumped into fresh water ponds and later reclaimed for shipment. It has a high moisture content together with high sulphur content this type of coal gives rise to high temperature from self heating and in the presence of moisture the sulphur leads to release of sulphuric acid resulting in corrosion of ships hold.

Liquification – Liquification is a process whereby moisture in the cargo migrates to the surface due to come compaction and vibration resulting in development of a flow state. This is particular in case of coal slurry, mud coal. This leads to reduction of ships stability.

PRECAUTIONS WHEN LOADING COAL

  • VENTILATION – Surface ventilation is an important necessity during the carriage of coal for two reasons:
    • To carry away any methane gas which may be given out.
    • To dissipate any heat formed by oxidation of coal.
  • TEMPERATURE – Monitoring of temperature at 3 levels in the hold to be done at least once a day.
    • Particular attention to be paid to cargo stowed against hot bulkheads, Which is to be avoided if possible.
    • Temperature pipes are to be closed to prevent entry of air to cargo hold.
  • FIRE
    • A sufficient number of safety lamps to be carried in all coal carrying vessel.
    • All electrical cables and components situated in the cargo space should be free from defects.
  • SHIFTING
    • A certificate is obtained from shipper stating the moisture content of the cargo. If figure is suspected, an onboard test of moisture should be carried out and we should be sure before loading.
    • Precautions should be taken to prevent ingress of water into the cargo.
    • Cargo work to be suspended and hatches to be closed during bad weather.

SULPHUR

PROPERTIES

  • TOXIC IN NATURE
  • SULPHUR COMBINES WITH SALT WATER PRODUCING SULPHURIC ACID.

HAZARDS

  • FIRE
  • DUST EXPLOSION
  • CORROSION

PRECAUTIONS

  • Sulphur dust can readily ignite causing an explosion. Hence sulphur is wetted with fresh water before loading to prevent dust.
  • Wetting sulphur might reduce the dust but increases the corrosive power of sulphur.
  • In general fresh water hose is rigged on deck.
  • If fire occurs spray of fresh water may be used, If not extinguished close the hatches and alll the ventilation and start CO2.

COTTON

A great risk of fire is present with cotton cargoes. This cargo is liable to produce heat especially when wet and can be subjected to spontaneous combustion.

PRECAUTIONS WHEN LOADING COTTON

  • Hold must be clean
  • Perfectly dry
  • Well aired
  • Free from grease
  • Must not be stowed in freshly painted holds as heat produced is likely to cause ignition of paint vapours.
  • Fire fighting equipment tested and ready for immediate use.
  • If using steam to fight fire, deck should not be cooled as this causes the steam to condense creating a vacuum.
  • Loosely packed bales or with broken bands allow air circulation making it easier to catch fire so they must be discarded.
  • Dunnage used should be clean, dry and free from grease or oil.