The loading mode is usually decided by whoever books the freight, and it is usually decided on cost per tonne. That is the wrong single criterion, because the mode also determines how much of the cargo arrives in specification, what the buyer can prove if it does not, and how much documentation the shipment carries. This guide sets out the realistic options for agricultural bulk out of Ukraine and comparable origins, what each one costs you in risk, and how to choose between them.
First question: is the cargo dry or liquid?
It sounds trivial and it is the fork in the road, because dry and liquid bulk share almost no equipment.
Dry bulk – grain, oilseeds, meal, groats, grits – moves by vessel hold, bulk container with a liner, big bag or sack. The quality risks are moisture migration, condensation, insect activity, taint from a previous cargo and physical damage to the grain from handling.
Liquid bulk – crude and refined vegetable oil – moves by parcel tanker, ISO tank container, flexitank, drum or IBC. The quality risks are contamination from previous cargo, water ingress, heat during the voyage and oxidation, and the whole documentary apparatus of previous cargo declarations exists because of the first of those.
Dry bulk options compared
| Mode | Typical parcel | Where it wins | Where it hurts |
|---|---|---|---|
| Handysize or supramax vessel | 20,000 to 60,000 t | Lowest cost per tonne at scale | Requires port infrastructure, draft, and a buyer who can absorb the parcel |
| Coaster or barge | 2,000 to 8,000 t | Short sea and river routes, smaller parcels | Weather delays, limited destinations |
| Bulk container with liner | 24 to 28 t per 40 ft | Small parcels, sealed integrity, door to door | Higher cost per tonne, stuffing and destuffing labour |
| Big bag in container | 20 to 25 t per 20 ft | No silo intake needed, lot separation | Handling cost, bag cost, dunnage |
| Palletised sack | 18 to 22 t per 20 ft | Retail-ready and small receivers | Highest cost per tonne of the dry options |
| Road trailer, bulk or bagged | 24 to 25 t | Neighbouring markets, fast turnaround | Only viable over short distances |
Two technical numbers govern whether a hold or a container is full by weight or by volume. The stowage factor is the volume a tonne of the commodity occupies, and it varies widely: wheat sits at roughly 1.25 to 1.30 cubic metres per tonne, barley at roughly 1.45 to 1.55, sunflower seed far higher because it is light and bulky. A commodity with a high stowage factor cubes out a container before it reaches the payload limit, which means the freight cost per tonne rises even though the container is nominally the same. Sunflower seed in shell is the textbook case: a 20 ft container holds perhaps 19 to 22 tonnes of it against 26 to 28 tonnes of meal.
The second is the angle of repose and cargo shift risk. Grain in a vessel hold is regulated cargo, and the International Grain Code sets requirements for stability and for securing partly filled holds. This is the ship’s business rather than the buyer’s, but it becomes the buyer’s problem when a fixture is delayed because a stability calculation does not work.
Why liners matter more than they look
A bulk container liner is a large polyethylene bag fitted inside a standard box, with a bulkhead at the door and a filling spout at the top. It costs relatively little and it does three things that matter:
- It seals the cargo from the container, which removes the previous-cargo and residual-odour question that would otherwise require a container history the shipper may not have.
- It controls moisture migration, which is the main quality risk in a container crossing climate zones. A container loaded warm in September and discharged cold in November will condense on the roof and rain onto the cargo; a sealed liner does not prevent temperature change but it substantially limits moisture exchange and keeps condensate off the grain.
- It keeps the lot identity clean, which matters for organic, non-GM and identity-preserved cargoes where the segregation chain is the product.
For an organic or non-GM cargo, a liner is effectively mandatory: the certification chain requires demonstrated segregation, and a bare container with an unknown history does not provide it.
Liquid bulk: flexitank against ISO tank
For vegetable oil the practical choice for parcels in the twenty-tonne range is between a flexitank and an ISO tank container, and they are genuinely different products.
A flexitank is a single-use bladder installed inside a standard 20 ft dry container, typically between about 16,000 and 24,000 litres, which for a refined vegetable oil corresponds to roughly 21 to 24 tonnes. It is cheap, it requires no tank repositioning, and because the liner is new it eliminates the previous cargo question entirely. What it demands in return is discipline: the shipping line must have approved the specific flexitank type for the container, a bulkhead must be fitted at the door because a partly filled liquid load surges, and the loading and sealing must be documented and photographed. It cannot normally be heated, it cannot be part-discharged in the way a tank can, and a bladder failure is a total loss of the parcel rather than a partial one. See what a flexitank is and how it is loaded for the mechanics.
An ISO tank container is a reusable stainless steel tank in a frame, typically 24,000 litres, carrying roughly 21 tonnes of oil. It can be steam heated, which matters for fats that solidify and for viscous cargoes, it can be part discharged, and it is mechanically robust. Because it is reused, its acceptability depends on a cleaning certificate and a previous cargo record, and for edible oils the reference point is the FOSFA list of acceptable previous cargoes, which exists precisely because a tank that last carried an unsuitable product cannot be made suitable by washing.
For larger volumes, a parcel tanker moves several thousand tonnes in segregated coated or stainless tanks, and the previous cargo and tank coating history become central contractual matters. For small volumes, drums at 190 to 200 kilograms and IBCs at around 1,000 litres remain the practical answer, at a substantially higher cost per tonne but with no bulk intake requirement at all.
Choosing: a short decision path
- What can the receiver actually take? Silo or tank intake, tipping station for big bags, or only palletised goods. This eliminates most options immediately and it is the question most often asked last.
- What parcel size does the commercial deal need? A trial or a first shipment argues for containers regardless of cost per tonne, because a vessel parcel commits volume before the quality relationship exists.
- How sensitive is the cargo to moisture, odour and heat? High sensitivity pushes towards liners, sealed formats and, for kernels and other fat-rich articles, barrier packaging.
- Does the cargo carry a segregation claim? Organic, non-GM or identity-preserved cargo needs demonstrable separation, which means liners, dedicated equipment and sealed loads with documented seal numbers.
- What does the documentation cost in each mode? Bulk vessel parcels bring draft surveys, hold cleanliness certificates and charter party terms; containers bring per-container weight verification and stuffing supervision. Neither is free.
- Where does the risk pass, and is that the same place the mode fails? Under FOB the buyer owns the voyage risk, so a mode whose failure mode is a voyage failure is a buyer problem, and the insurance should be arranged accordingly.
Things that go wrong, and the cheap fixes
- Condensation damage in containers. Loading warm cargo for a cold-climate discharge. Fixes: a liner, desiccant, ventilated liners on some commodities, and loading at a stable moisture rather than at the contract maximum.
- Previous cargo taint. Grain and meal pick up odour readily. Fix: liner for dry cargo, and for liquid a certified cleaning plus the previous cargo record checked against the FOSFA list.
- Insect activity discovered at discharge. Fix: fumigation with a proper record, insect monitoring in store before loading, and an agreed inspection point in the contract so a finding has a defined consequence.
- Flexitank surge damage. Fix: carrier-approved flexitank, correct bulkhead, and correct fill level. This is not negotiable, and a partly filled bladder is dangerous rather than merely suboptimal.
- Weight disputes. Fix: agree the weight determination method in the contract, draft survey or weighbridge, and appoint the surveyor jointly.
- Cubing out unexpectedly. Fix: calculate on the stowage factor for the actual commodity and grade before quoting a freight cost per tonne.
Mode selection is not a back-office decision. It sets the achievable quality at discharge, the evidence available in a dispute and a meaningful part of the landed cost, and on a first shipment with a new supplier it is usually worth paying the container premium to keep the parcel, and the exposure, small.