Transport
Transport
Transport includes:
- Petroleum Oil from the ocean to the land and across the land
- Workers out from land to oil rigs and back
- How Rigs are moved to ocean from land and around in the ocean
Crude Petroleum is transported either through pipeline, in sea tankers or in road tankers. On land petroleum can be transported through a pipeline or in road tankers and across water it can be transported through pipeline or in sea tankers.
Pipeline System
In the pipelines a system of small-diameter, short, interconnected pipes carry oil from wells to a larger-diameter trunk pipeline. The trunk pipeline system takes the oil to refineries, ports or storage areas. The pipeline system is controlled from one central control room. In this room the pipeline and flow are monitored and valves along the system can be remotely opened or closed.
The pipeline is made up of sections of steel pipe called joints. These can be between 20 to 61 centimetres in diameter and up to 12 meters long. The joints are hand welded together by welders. The pipes on land welders move up the pipeline welding each joint of the pipes together. They have dismountable huts built over them for protection from the sun, heat and weather, as it is already very hot using the welding equipment without the hot sun beating down on the welder. The welds are inspected with X-Ray equipment to check for cracks or fractures that could create major leaks, any cracks or fractures are fixed up before the pipe is put into use. The pipe is then coated in tar enamel paints or other chemicals by a coating machine to prevent corrosion. The coating is covered with a spiral wrap of heavy paper or plastic tape for protection. Pipelines are buried on land so they do not affect the surroundings. To bury them a ditching machine digs a trench of a depth of about 1 to 2 meters deep. The pipeline is then lowered into the trench by specially designed tractors and the trenches are covered back up with dirt.
Pipelines on the ocean floor are laid for short distances by lay barges. The joints are welded together on the lay barges by hand before they are lowered to the ocean floor and put into place. Offshore or river crossing pipes are coated in cement to prevent them from floating to the surface as they can become very buoyant.
At the beginning of a trunk pipeline on land is an inlet station, which has storage facilities and pumps or compressors. At the end of the pipeline is an outlet station. Pump stations at regular intervals along the pipe keep the oil moving. Instruments in the pipeline monitor the flow, temperature and pressure of the oil in the pipes. The data is then transmitted to the central control room. Along the pipeline are block valve stations. These have valves that can be closed from the central control room to isolate a section of the pipeline for maintenance or to contain a leak.
Road Tanker
Many smaller oil fields are not connected to a refinery by pipeline. When stock tanks are full of crude oil it is then transferred to a road tanker, or tanker truck. These trucks take the oil to refineries or to wherever else it is needed by road. Disadvantages of using tanker trucks instead of pipelines to transport petroleum is that there is more chance of it spilling as trucks can crash and truck drivers may go on strike which would result in the petroleum not being able to be delivered for the duration of the strike. Advantages of using tanker trucks are that a petroleum company does not have to own them but can hire them and get a tanker truck company to take their product to where it is needed.
Sea Tankers
The most efficient and economical method to transport petroleum across the ocean is by crude sea tankers instead of pipelines. These sea tankers are Very Large Crude Carrier (VLCC) or Ultra Large Crude Carrier (ULCC). A super tanker typically holds 2 million barrels (320,000 cubic meters) of oil and can be up to 450 meters long. Super Tankers are a cheap option for petroleum companies operating subsea, as pipelines do not have to be laid down which can be very expensive, take time and requires maintenance. Super Tankers are mostly owned by petroleum ferrying companies. This means the petroleum companies pay for the transport of the petroleum when it is used and not upfront when pipelines are laid. Sea Tanker transport for petroleum is suitable for medium to long distances across oceans or water.
When a Super Tanker is full the ship lies lower in the ocean and can only be docked at deepwater ports. At other ports the tanker must be lightened by transferring oil through flexible hoses to smaller tankers. The tankers can also be docked in deep water at single-mooring buoys located at the inlet station of a submarine pipeline, which brings the oil ashore.
When natural gas is transported either by sea or land tankers it is refrigerated to -160’C so the particles of the gas are hardly moving. This means the gas takes up a lot smaller space and the tankers can hold up to 700 times more gas than if the gas was at its normal temperature. There are no refrigerators on the tankers holding the gas, the gas is cooled then transferred to the containers on the sea or road tanker. These containers are highly insulated so the temperature of the gas hardly drops and can stay cool for up to ten days. Any gas that is warmed up is caught and reused by the tanker by being put into the engine to help it run and be energy efficient.
Transport includes:
- Petroleum Oil from the ocean to the land and across the land
- Workers out from land to oil rigs and back
- How Rigs are moved to ocean from land and around in the ocean
Crude Petroleum is transported either through pipeline, in sea tankers or in road tankers. On land petroleum can be transported through a pipeline or in road tankers and across water it can be transported through pipeline or in sea tankers.
Pipeline System
In the pipelines a system of small-diameter, short, interconnected pipes carry oil from wells to a larger-diameter trunk pipeline. The trunk pipeline system takes the oil to refineries, ports or storage areas. The pipeline system is controlled from one central control room. In this room the pipeline and flow are monitored and valves along the system can be remotely opened or closed.
The pipeline is made up of sections of steel pipe called joints. These can be between 20 to 61 centimetres in diameter and up to 12 meters long. The joints are hand welded together by welders. The pipes on land welders move up the pipeline welding each joint of the pipes together. They have dismountable huts built over them for protection from the sun, heat and weather, as it is already very hot using the welding equipment without the hot sun beating down on the welder. The welds are inspected with X-Ray equipment to check for cracks or fractures that could create major leaks, any cracks or fractures are fixed up before the pipe is put into use. The pipe is then coated in tar enamel paints or other chemicals by a coating machine to prevent corrosion. The coating is covered with a spiral wrap of heavy paper or plastic tape for protection. Pipelines are buried on land so they do not affect the surroundings. To bury them a ditching machine digs a trench of a depth of about 1 to 2 meters deep. The pipeline is then lowered into the trench by specially designed tractors and the trenches are covered back up with dirt.
Pipelines on the ocean floor are laid for short distances by lay barges. The joints are welded together on the lay barges by hand before they are lowered to the ocean floor and put into place. Offshore or river crossing pipes are coated in cement to prevent them from floating to the surface as they can become very buoyant.
At the beginning of a trunk pipeline on land is an inlet station, which has storage facilities and pumps or compressors. At the end of the pipeline is an outlet station. Pump stations at regular intervals along the pipe keep the oil moving. Instruments in the pipeline monitor the flow, temperature and pressure of the oil in the pipes. The data is then transmitted to the central control room. Along the pipeline are block valve stations. These have valves that can be closed from the central control room to isolate a section of the pipeline for maintenance or to contain a leak.
Road Tanker
Many smaller oil fields are not connected to a refinery by pipeline. When stock tanks are full of crude oil it is then transferred to a road tanker, or tanker truck. These trucks take the oil to refineries or to wherever else it is needed by road. Disadvantages of using tanker trucks instead of pipelines to transport petroleum is that there is more chance of it spilling as trucks can crash and truck drivers may go on strike which would result in the petroleum not being able to be delivered for the duration of the strike. Advantages of using tanker trucks are that a petroleum company does not have to own them but can hire them and get a tanker truck company to take their product to where it is needed.
Sea Tankers
The most efficient and economical method to transport petroleum across the ocean is by crude sea tankers instead of pipelines. These sea tankers are Very Large Crude Carrier (VLCC) or Ultra Large Crude Carrier (ULCC). A super tanker typically holds 2 million barrels (320,000 cubic meters) of oil and can be up to 450 meters long. Super Tankers are a cheap option for petroleum companies operating subsea, as pipelines do not have to be laid down which can be very expensive, take time and requires maintenance. Super Tankers are mostly owned by petroleum ferrying companies. This means the petroleum companies pay for the transport of the petroleum when it is used and not upfront when pipelines are laid. Sea Tanker transport for petroleum is suitable for medium to long distances across oceans or water.
When a Super Tanker is full the ship lies lower in the ocean and can only be docked at deepwater ports. At other ports the tanker must be lightened by transferring oil through flexible hoses to smaller tankers. The tankers can also be docked in deep water at single-mooring buoys located at the inlet station of a submarine pipeline, which brings the oil ashore.
When natural gas is transported either by sea or land tankers it is refrigerated to -160’C so the particles of the gas are hardly moving. This means the gas takes up a lot smaller space and the tankers can hold up to 700 times more gas than if the gas was at its normal temperature. There are no refrigerators on the tankers holding the gas, the gas is cooled then transferred to the containers on the sea or road tanker. These containers are highly insulated so the temperature of the gas hardly drops and can stay cool for up to ten days. Any gas that is warmed up is caught and reused by the tanker by being put into the engine to help it run and be energy efficient.
Pipelines vs. Tankers
Large Capital Investment
Low Operating Costs Low Maintenance Costs Suitable for Short/Medium Distances Low Spill History Money Up-Front Available Anywhere No strikes |
Smaller Capital Investment
Higher Operating Costs Higher Maintenance Costs Suitable for Medium/Long Distances High Spill History Pay when used Requires Water Higher Strike rate |