Author: Dr. Theo Notteboom
Dry bulk, liquid bulk, roll-on-roll-off (RORO), and breakbulk terminals have a diversity of terminal designs and functions and a broad range of quay, yard and warehousing equipment.
1. Major Dry Bulk Terminals
The term major bulk refers to commodities that are transported in very large quantities using bulk carriers. Three major components impact bulk terminal design:
- Supply characteristics. Resources carried by bulk are extracted according to geographic (minerals and fossil fuels) and climatic conditions (agricultural goods and wood products). Some, such as coal, iron ore, and petroleum, have a high level of concentration, while others, such as agricultural goods, are collected over extensive areas.
- Demand characteristics. Each bulk market has a demand-pull related to intermediary processing and manufacturing activities. The location of these facilities, usually adjacent to port sites, considers the demand for the resources over an extensive market and a material index (ratio of inputs over outputs). The demand for bulk commodities is usually managed by large commodity traders and brokers able to consolidate purchases and distribution in large quantities.
- Potential for economies of scale. The economic rationale in using the largest ship size possible considering the geographical distribution of the supply and demand is fundamental in the bulk market. This potential is limited by the characteristics of the waterways at the port of origin, in transit (e.g. Panama, Suez), and at the port of destination. The outcome is a wide range of bulk ship classes trying to reconcile supply, demand, and economies of scale.
Major dry bulk commodities include iron ore, coal, and grains. They are not homogeneous as there are several grades of coal used for making steel (coking coal) and energy generation (steam coal). Each represents a different market, implying a segmentation of the bulk trades. Further, there is an important directionality to bulk trade, implying that export bulk terminals are designed rather differently from import bulk terminals:
- Export terminals for coals and iron ore combine stacker reclaimer systems and ship loaders to connect the yard to the bulk carriers. A good example of a major export terminal for dry bulk is Port Hedland in Australia, the world’s largest coal export port. Export terminals facilitate outgoing cargo flows and are strongly synchronized with the inland transport system (mostly rail-based) that connects the mining areas to the terminal. Export terminals try to limit stocks but sometimes have to keep a large (unsold) stock to support commodity trade pricing. In most cases, export terminals handle a limited number of material types due to their location in relation to mining areas or due to their ownership, as many export terminals are owned by traders or mining companies. The location of many export terminals is a compromise between the hinterland and maritime accessibility.
- Import terminals for coal and iron ore use unloaders equipped with large grabs to discharge the commodities. There are several types of quay cranes and grabs available. The choice of the crane type depends on the operational needs of the terminal operator in terms of ship sizes to be served and minimum cargo handling productivity in tons per hour. Conveyor systems transport the discharged commodities along the quay and onto the yard. As import terminals usually handle multiple types and grades of major bulks, stockpiles of bulk material are spread across the yard. The terminal surfaces of import terminals are quite large to avoid cross-contamination between stockpiles and comply with necessary certification requirements. Stacker reclaimers are used to transport the bulk products from the yard to the loading stations for seagoing vessels, inland barges, and railcars. A good example of a major import terminal for dry bulk is EMO in Rotterdam, one of the largest dry bulk terminals in Europe. Import terminals for handling major bulks rely heavily on rail and barge (where available) for hinterland transportation. They have to match services to both the waterside and the landside modalities. The most advanced bulk terminals are equipped with automated railcar loading/unloading systems. Terminal planning is quite challenging as vessels usually arrive in a stochastic manner, and the consignee selects landside services and inland modalities.
Coal and iron ore terminals might offer additional services such as washing, screening to separate the bulk material into different grades, blending silos, and compacting to prevent spontaneous combustion. Terminals limit environmental effects by investing in technology to save energy and reduce noise and dust emissions.
Dust control is a key concern at dry bulk terminals. Whenever a transfer of coal or iron ore occurs, there is a potential to break the lumps, resulting in dust, which can be spread by crosswinds. Once the coal or iron ore is stockpiled, dust can still be a problem. Even if it arrives wet, wind across the stockpile can evaporate the moisture and dust will be lifted. Any vehicles driving over crushed lumps will also raise dust. Several measures are taken to reduce dust emission, such as:
- Dust covers on grabs and conveyors.
- Fogging systems that release small droplets of water into the air, forcing dust to precipitate.
- Sprinkler systems spray water on stockpiles to keep them damped down. This includes an adapted drainage system and on occasion a water recycling station.
- Optimized stockpile design such as avoiding edges that can dry quicker than a rounded surface.
- Add a protective layer over the stockpile such as a skin formed by a water additive.
- In case of loading operations in the vessel holds, loading chutes with heavy-duty dust skirts can be used in order to prevent dust cloud formation arising from the product falling onto the peak of the product pile in the hold.
The capacity of a dry bulk terminal to transload coal or iron ore is determined by many factors, such as the quay length, the yard dimensions, the quay and yard equipment, the stockpile patterns and heights, the storage time distribution of the bulk material, the number of types and/or grades handled, the terminal operating hours (waterside and landside), the arrival patterns, types and sizes of ships and land transport modes. The use of an existing terminal can be further optimized by improving berthing/unberthing procedures, optimizing vessel traffic rules, synchronizing vessel and landside operations, reducing downtime (caused by hatch changes, shift changes, or breakdowns), and installing provisions that allow all-weather operations. In some cases, dry bulk is not handled at terminals, but using offshore handling facilities.
Grain terminals are designed to handle and store wheat, soy, and other grains and oilseeds. There are many models of both discontinuous systems (such as those using grabs) and continuous ship unloaders (CSU), including pneumatic chain, screw, or twin-belt machines. Grain elevators stockpile or store grains using bucket elevators or pneumatic conveyors that scoop up grain from a lower level and deposit it in a silo or other storage facility. Large grain terminals can have dozens of large silos located next to each other. Many grain terminals offer additional services such as cargo sieving in order to calibrate the grain, and fumigation. Many factors influence the performance of unloading systems, such as ship type and size, type of product, the number of product impurities, product density, adverse weather conditions, and down-times.
2. Minor Dry Bulk Terminals
Minor bulks include cargoes such as fertilizers, bulky agricultural products, cement, sand, petroleum coke, and metal scrap. While major bulks are often loaded in large bulk carriers (such as Capesize and Panamax vessels), minor bulks are usually transported by sea in smaller and more versatile vessels such as handymax ships and coasters. The term minor bulk is derived from the potential economies of scale that can be realized due to market size and demand patterns that are more dispersed than for major bulk trades. Just like for major bulks, minor bulks are placed or poured into cargo holds. The terminal superstructure includes:
- Cranes and conveyors. Portal quay cranes, jib cranes, mobile cranes, floating cranes, and loader/unloader systems are deployed to load and discharge minor bulks, combined with conveyor and elevator systems where required. The cranes are equipped with specialized grabs, mostly of the clamshell type. The grabs can be operated by ropes (single-rope, two-rope, or four-rope clamshell buckets), electro-hydraulically or diesel hydraulically.
- Yard and warehouse vehicles. The cargo handling operations are supported by different types of yard and warehouse vehicles such as bobcats, tractors, trailers, forklifts, and front-end loading shovels (fitted with a pusher).
- Other equipment at the yard and the covered storage facilities can include weighbridges, hoppers (where the product is loaded into trailers or trucks), blending silos, and bagging plant facilities.
- Minor bulk storage facilities can be in the open air or covered in warehouses and are typically sectioned off into separate bays to enable various products or grades to be stored.
Minor bulk terminals face a wide range of possible operational risks such as cross-contamination of cargo types, water ingress, and fire/ignition/explosion hazards. The handling of bulk ships can be rather dangerous, with specific rules and regulations related to cargo movement and immersion.
3. Liquid Bulk Terminals
Liquid bulk terminals are equipped to handle cargoes in liquid and gaseous forms, such as crude oil, oil products, LNG, and LPG. These products are shipped by oil tankers, chemical tankers, parcel tankers, and gas carriers. The oil tanker fleet consists of various ship sizes and has been particularly prone to economies of scale considering the global demand for petroleum, one of the most extensively traded commodities. A common size is the Very Large Crude Carrier (VLCC) of around 200,000 dwt. LNG carriers can be grouped into different sizes depending on the trade route concerned and service a market that has seen rapid growth. Chemical and parcel tankers are designed to carry an assortment of liquids, such as chemicals, or different grades of a liquid, like petroleum, at one time. They usually have a capacity in the range of 25,000 to 80,000 dwt, although smaller units are used for coastal trade.
The loading and unloading of tankers needs special equipment such as loading hoses or loading arms. These loading arms include safety accessories and are often geared with remotely operated quick couplers. Loading arms consist of a piping assembly with moveable pipes. The flexibility is achieved by swiveling joints. Because of the high weight of the steel piping, the moveable pipes are counterweight balanced. The loading arms can have one or two liquid lines and, if needed, can be equipped with a vapor line. The loading arms can be installed on jetties or regular quay walls.
The capture and recovery of hydrocarbon vapor or volatile organic compounds (VOC) to reduce emissions is vital in modern oil and gas terminal handling and storage. The requirements for the vapor recovery systems depend on the type of product handled and stored. Vapor from the cargo tanks passes through a vapor head to a recovery unit. Sulfur components in the vapor are removed before entering the vapor recovery system.
The yard of a liquid bulk terminal usually contains a mix of tank storage facilities and other technical installations such as pump stations. Many liquid bulk terminals are directly connected by pipeline to chemical or petrochemical production sites.
4. RORO Terminals
There are several types of roll-on-roll-off (RORO) terminals, each focused on specific market segments. First, there are terminals equipped to handle RORO and ropax vessels (ferries), which operate on end-to-end type services with a port of call at either side of the route. The ferry capacities tend to vary greatly. For example, in Europe, the large units deployed on the English Channel and parts of the Baltic can handle 120 trucks per voyage. In contrast, vessel capacities on services in smaller markets (e.g. the Irish isles) tend to be more limited.
The short-distance RORO services market can involve accompanied transport, where truck-trailer combinations go onboard with drivers, or unaccompanied transport, where trailers make the crossing without drivers. In the latter case, the trailer is positioned onboard using a special tractor, which allows for more capacity, but requires more handling at the terminals. It is also possible for a 40 or 45-foot container to be positioned on a chassis and then loaded on board, which allows ferries to support containerized trade.
Terminals used for ferry crossings are designed for the fast turnaround of the vessel. The apron is usually equipped with fixed ramps. Simultaneously, the yard includes extensive parking facilities for trucks and cars waiting to board and an administrative building, including a ticketing office and customs office if applicable. A good example of a large ferry terminal complex is the Calais Ferry Terminal on the French side of the English Channel. The terminal specializes in cars, accompanied trucks, and passengers making the crossing to the UK.
The required shape of the quayside of a RORO terminal depends on the type of ramp the visiting vessels have. In most cases, a straight quay wall suffices. However, when the vessel uses a bow or stern ramp, the quay wall might have a small outward extension to facilitate vessel handling.
Second, there are terminals specialized in handling new (and second-hand) cars and rolling material. The deepsea and shortsea car carrying trade is an important segment in the RORO market as it supports an active international trade of motor vehicles with Germany, Japan, and South Korea as the lead exporters. On long-distance routes, operators deploy Pure Car and Truck Carriers (PCTC) with capacities of up to 8,000 CEU (car equivalent units). A number of large car ports have successfully combined deepsea services with intra-regional shortsea services. The resulting hub-and-spoke network configuration is combined with growing local clusters of automotive logistics companies. While road haulage is by far the dominant mode of inland transport for car terminals, rail and barge, particularly in the Rhine and Yangtze river basins, play an ever more important role in securing the inland access of the larger car ports.
New car terminals usually cover large surfaces. Vans bring dock workers on board, after which they each pick a car to be driven down the ramp and parked on a designated spot on the yard. The yard is designed as a large parking area with small distances kept between cars. Specific parking configurations are deployed to maximize the productivity of terminal land without limiting access to the parked vehicles. For example, a 5 by 4 block configuration implies that a maximum of one car needs to be moved to reach any car within this block. Different types of parking configurations can be combined at the same terminal, such as 5×4 blocks for longer-term storage and a fish-bone configuration for the pre-sorting of cars in view of loading operations onto trucks or rail wagons. Some terminals have opted for multi-deck car storage facilities to reduce their spatial footprint. These multi-deck facilities come at an additional cost and are mostly found in ports with land availability issues and high concession fees. The automotive customer might specifically request multi-deck storage for economic, safety, or environmental reasons.
Car terminals are usually equipped with one or more PDI centers (Pre-Delivery Inspection). PDI activities are performed at the request of the car manufacturer or importer. They can include car inspection, repair of transport damages, installing car options, dewaxing, cleaning, and removing the transport wrap or foil. Advanced terminal operating systems (TOS) assist the terminal manager in tracking individual vehicles during their arrival at, stay, and departure from the terminal.
To cater for the increasing electrification of cars and the rise of fully electric vehicles (EVs), a number of larger terminals have invested in battery charging facilities at the yard, often powered by green energy such as wind turbines.
Many car and truck terminals combine RORO activities with break bulk or container handling and storage. This is particularly the case when the terminal is visited by conro (container/roro) ships.
5. Breakbulk Terminals
Breakbulk is general cargo, loaded into a ship or transport mode as individual or bundled pieces, not stowed into a container, or not transported in ship-sized liquid or dry bulk loads.
Conventional general cargo or break bulk cargo encompasses a myriad of different commodities:
- Project cargo, including power generation equipment such as generators, turbines, wind turbines, equipment for the oil and gas industry, cables on reels, gas tanks, modules, petrochemical plants, mining equipment, building, construction equipment, brewery tanks, silos, and heavy machinery.
- Iron and steel products such as coils, plates, steel bars, slabs, plates, steel wire, pipes, and tubes.
- Forest products such as lumber and paper products.
- Parcels and bags such as malt, fertilizer, sugar, and rice.
- Reefer vessel trades, including fruit and meat.
- Break-bulk shipments of smaller lots such as large bags, skidded and palletized cargoes.
A more detailed discussion on the breakbulk markets is provided in Chapter 8.2. The wide range of breakbulk cargoes implies there are also many types of terminals and handling equipment available. Many breakbulk terminals are highly specialized to handle one specific type of breakbulk cargo and cannot be readily converted to other uses.
Breakbulk cargo is handled by cranes on the quay, floating cranes, or the ship’s own cargo gear (deck cranes, derricks). On the docks, various types of dockside cranes, level-luffing cranes, and mobile cranes are used for moving and lifting packages. All the vertical cargo movements are conducted by the lifting gear (lift-on/lift-off equipment). Attached to such lifting gear is a shackle that links the crane or derrick with the cargo-handling equipment being used. For most lifts, a hook is used. There are numerous types of tools or loose gear that can be attached to the shipboard or shore-based lifting gear:
- Sling or strop, which is probably the most common form of loose gear. Such equipment, generally made of rope, is ideal for hoisting strong packages, such as wooden cases or bagged cargo, which is not likely to sag or be damaged when raised.
- Snotters or canvas slings are suitable for bagged cargo.
- Chain slings are used for heavy slender cargoes, such as timber or steel rails.
- Can or barrel hooks are suitable for hoisting barrels or drums.
- Cargo nets are suitable for mail bags and similar cargoes that are not liable to be crushed when hoisted.
- Heavy lifting beams are suitable for heavy and long articles such as locomotives, boilers, or railway passenger coaches.
- Cargo trays and pallets, the latter being of wooden or steel construction, are ideal for moderate dimension cargoes, which can be conveniently stacked, such as cartons, bags, or small wooden crates or cases.
Forklift trucks are frequently used on break bulk terminals. This type of equipment can be mechanically or electrically operated and fitted in front with a platform in the shape of two prongs of a fork. Lifting capacity varies from 1 to 45 tons. Clamps for reels and bales are provided on some forklift trucks.
In the case of palletized breakbulk cargo, pallet jacks are used as well to lift and move pallets. The front wheels are mounted inside the end of the forks, and as the hydraulic jack is raised, the forks are separated vertically from the front wheels, forcing the load upward until it clears the floor. The pallet is only lifted enough to clear the floor for subsequent travel.
Many commodities such as coffee, cocoa, tobacco, and bananas used to be transported and handled as break bulk. At present, these commodities are mostly containerized. Once the container has been discharged, it is transported to a specialized terminal in the port area or the hinterland. The container is stripped for storage, distribution, and value-added logistics activities (VALS) regarding its content.
In some cases, a commodity is discharged at a terminal equipped to handle both breakbulk vessels and containerized cargo. For example, this is the case at many banana import terminals where reefer container trade meets traditional reefer vessels carrying palletized banana boxes in their holds.
- Chapter 3.1 Terminals and Terminal Operators
- Chapter 3.2 Terminal Concessions and Land Leases
- Chapter 3.7 Dock Labor
- Chapter 3.8 Terminal Automation
- Chapter 8.1 Cruise Ports
- Chapter 8.2 Break-Bulk
- Further references to be added