How fossil fuelsmove the world Condensate
Not all types of crude oil are the same
Some oils are light, can be used almost immediately and are therefore very valuable. Other oils are heavy and have to undergo additional refining processes before they can be used. One of the lightest and most valuable crude oils is condensate which is used to produce products like petrol, jet fuel, diesel and heating fuels.
What does condensate look like?
Condensate comes in various colors, from clear like water to yellow or even brown. For example, the Achimov condensate that Wintershall produces at the Urengoy field in Siberia is an orange-yellow liquid. Compared to conventional crude oil, condensate is much thinner and has a similar consistency to normal water at room temperature.
Where are condensate and its by-products used in everyday life?
When you fly to your holiday destination, the aircraft will most likely be powered by JET-A1, one of the most common types of kerosene. Kerosene is a special jet fuel for aviation and is made from crude oil and condensate.
Anyone who lights a lighter or cooks with a camping stove uses liquid gases supplied from a container.
These flammable gases are liquid under pressure, become gaseous when they flow out and keep the flame burning.
Liquid gas is a component of condensate and is separated during subsequent processing steps.
Why is condensate so valuable?
Condensate is an extremely high-quality light oil. In comparison to normal crude oil, condensate needs to undergo fewer refining processes and is therefore very economical from the start.
Crude oils are classified according to their API gravity. The lower the API gravity, the heavier the oil is and the more complex the refining process.
Because of the less complex refining process condensate is a ressource that is very much in demand.
Condensate is further processed to produce petrol, diesel or aviation fuels such as kerosene. It can also be used as a ressource in petrochemistry to produce synthethic materials. A part of the condensate produced by Wintershall from the Achimgaz fields is also mixed with oil to create "Russian Blend" and then sold on the world market.
How is condensate produced and treated?
Condensate is obtained from gas condensate reservoirs and is separated from natural gas using various processes. The treatment process is explained here using Wintershall's Achimov condensate as an example.
The reservoir containing a mixture of natural gas and condensate lies at a depth of 3,000 - 4,000m. This mixture - the gas condensate - is under high pressure and therefore flows upwards unaidedly. Pumping is not necessary. The gas condensate collected is transported to a processing facility. Here, the temperature of the gas condensate is reduced until it separates into condensate, water and gas.
The collected gas condensate is then transported via pipelines to refineries for further processing.
Collection and inlet separationThe gas condensate produced from various wells is collected and fed into the processing facility. A gas liquid mixture enters the processing facility. In the entry separation heavier condensate and water are seperated.
Cooling and low temperature seperationIn the next step the gas is cooled down to -30°C - in this process additional condensate is generated.
Gas The gas is then transported to Europe via pipelines.
Condensate The condensate is transported via pipelines to refineries where it is processed.
Condensate and its aggregate states
Depending on the temperature, condensate can take on various aggregate states - from liquid to solid. Examples of the aggregate states for Achimov condensate are shown below.
How is condensate transported in pipelines?
Because condensate remains liquid only under specific conditions, it is not easy to transport it via pipelines - and transporting the Achimov condensate is particularly difficult given the cold conditions in Siberia.
To ensure that the condensate does not solidify, it must be transported via pipelines at a temperature above 25°C. If the condensate cools further, it will eventually solidify owing to the paraffins it contains.
In a worst-case scenario, a pipeline containing liquid condensate would turn into a candle many kilometers long, resulting in a complete blockage. In order to avoid this, the temperature of the pipelines is monitored closely and is raised by heating if necessary.
The pipeline which transports Achimov condensate lies around a meter beneath the earth. This prevents cooling owing to the cold wind close to the polar circle.
The pipeline passes through heating stations located at regular intervals above ground. In these heating stations, the condensate can be heated with burners to prevent it solidifying and blocking the pipeline. The burners are fueled with gas obtained during the gas condensate production process.