Aromatic extraction unit: water transportation and oil transportation.
Thread Content
Recently, I reviewed the commissioning plans for aromatic extraction units submitted by several companies, and noticed that most of them use water-based circulation systems, as well as cold oil and hot oil circulation systems. Being quite inexperienced, I was wondering if anyone with more knowledge could explain the advantages and disadvantages of each of these circulation methods for aromatic extraction. Should the aromatic extraction unit be operated with hot and cold oil?
Joint commissioning is necessary in order to check the performance of the instruments on new equipment, determine whether there are any leaks in the processes, identify and address issues, and train operators.
Generally, devices are transported by water or oil; water is used for training, while oil is used to test instruments, clean pipelines, and use hot oil to check for leaks and ensure tightness – each method has its own advantages
If the extraction unit is operated using oil, it will prolong the startup time; after other units have finished operating with oil and the oil is removed, it can be directly used again. However, the extraction unit uses a solvent, and as a result the hydrocarbon content in this solvent is high. Moreover, even when using oil for extraction, is it necessary to use a special type of oil for this purpose?
The hot and cold oil circulation in the aromatic hydrocarbon plant can be carried out first; this is what I mean. Purchased crude oil suitable as an aromatic feed is used, with a large-scale circulation of oil throughout the entire plant, and the same applies to extraction. The hydrocarbon content in the extraction solvent is not high, unless the operation is not carried out properly; under normal production conditions, once the material from the upstream reforming unit meets the required standards, it can be fed directly into the system. After the product analysis shows it meets the specifications, the cycle can be switched to sending the product out for use.
For water transportation, it is necessary to check for flange leaks and the operation of pumps; for oil transportation, it is essential to remove water and apply heat to achieve tightness – both procedures are required, rather than just choosing one of them.
How should contaminated oil be handled after it has been extracted and transported? It’s the extraction and delivery pipeline over there, right?
After displacement and water washing, the extract contains basically no impurities. During transportation, some of the oily waste can be discharged into the oily waste tank, while the rest can be treated as product
So, the oil after being transported can still be used as a raw material, right?
Yes, because it is itself the raw material for extraction