Dangers when transporting bulk cargo on bulk carriers

Brodovi za prijevoz rasutih tereta specijalizirani su brodovi koji su se razvili 60-ih godina kao uzrok povećanja potražnje za prijevozom većih količina suhog rasutog tereta. Glavne značajke tih brodova su jedna glavna paluba s velikim otvorima skladišta, vlastita prekrcajna sredstva na manjim brodovima te nadgrađe, strojarnica i zapovjedni most na krmi broda. Skladištni prostor tereta najvažniji je element broda. Sustav balasta ima veliku ulogu u održavanju pozitivne stabilnosti broda tijekom plovidbe praznog broda. Brodove pogone sporohodni dizelski motori s fiksnim krilima te postižu brzinu između 13 i 15 čvorova. Brodove za prijevoz rasutih tereta dijelimo po veličini i vrsti. Glavni problem kod ovih brodova su sile i momenti koji dijeluju na brod pod utjecajem tereta. Ugradnjom HMSS-Hull Stress Monitoring System sustava smanjila se opasnost. Glavni uzroci strukturnih problema su korozija, pad tereta na oplatu dna skladišta, prijevoz korozivnog tereta, oštećenja prouzročena teretnom opremom, zamor metala te operativni faktori. Svaki od tih uzroka na svoj način šteti brodu i čvrstoći brodske konstrukcije. Glavni uzrok svih nesreća i dalje je ljudski faktor. Svaki brod mora imati izrađen plan ukrcaja/iskrcaja tereta koji će zadovoljiti pozitivnu stabilnost tijekom operacija i koji će zadovoljiti sigurnosne zahtjeve vezane za sile i momente savijanja. Sekvence ukrcaja/iskrcaja moraju biti usklađene s krcateljem te mora biti osigurana dovoljna količina tereta za završni trim broda. Svaki rasuti teret donosi određene opasnosti prilikom prijevoza morem. Teški tereti neravnomjerno opterećuju dno skladišta. Pomak tereta u navigaciji može drastično ugroziti stabilnost, kako bi se to spriječilo određene terete se poravnava ili ih se ukrca do vrha skladišta. Problem likvifikacije kod tereta s velikom količinom vlage, a koja pod utjecajem vibracija i valjanja broda, pretvara teret u tekuće stanje. Samozapaljenje i samozagrijavanje tereta može izazvati ozbiljne probleme na brodu osobito na otvorenom moru. Određeni tereti mogu izazvati kemijske reakcije te se prema IMSBC kodu svrštavaju u opasne terete. Ostali problemi izazvani teretom su manjak kisika, prašina nastala rukovanjem teretom te neke ostale kemijske reakcijeBulk carriers are specialized ships that developed in the 1960s as a result of increased demand for the transportation of larger quantities of dry bulk cargo. The main features of these ships are one main deck with large storage hatches, own cargo handling gear on smaller ships and a superstructure, engine room and command bridge at the stern of the ship. The cargo hold is the most important element of the ship. The ballast system plays a major role in maintaining the positive stability of the ship during the navigation of the empty ship. The ships are powered by slow-moving diesel engines with fixed wings and reach a speed of between 13 and 15 knots. Bulk carriers are divided by size and type. The main problem with these ships are the forces and bending moments acting on the ship under the influence of the load. By installing the HMSS-Hull Stress Monitoring System, the danger was reduced. The main causes of structural problems are corrosion, load falling on the double bottom tank, transportation of corrosive cargo, damage caused by cargo equipment, metal fatigue and operational factors. Each of these causes damages, in its own way, to the ship and the strength of the ship's structure. The main cause of all accidents is still the human factor. Each ship must have a cargo loading/unloading plan designed to ensure positive stability during operations and to meet safety requirements related to forces and bending moments. Loading/unloading sequences must be coordinated with the shipper and a sufficient amount of cargo must be provided for the final trim of the ship. Every bulk cargo carries certain risks during sea transportation. Heavy loads unevenly load the bottom of the holds. The movement of the load in the navigation can drastically threaten the stability, in order to prevent this, certain loads are leveled or loaded to the top of the hold. The problem of liquefaction in cargo with a large amount of moisture, which under the influence of vibrations and rolling, turns the cargo into a liquid state. Self-ignition and self-heating of cargo can cause serious problems on board, especially on the open sea. Certain cargoes can cause chemical reactions and are classified as dangerous cargoes according to the IMSBC code. Other problems caused by cargo are lack of oxygen, dust created by cargo handling and some other chemical reactions