Fushun industry

I spotted this interesting chemical plant in Fushun but had no idea just what was going on there. I am now wondering if this is something to do with the large shale oil processing plant that exists there. The two plants use the modified Fushun retort system and produce between them around 350,000 tonnes of oil per year. One plant has 120 retorts and the other has 100.

The Fushun process is classified as an internal combustion technology but also includes external gas heating. It uses a vertical cylindrical type shaft retort, with outside steel plate lined with inner fire bricks. The retort has height over 10 metres (33 ft) and its inner diameter is about 3 metres (9.8 ft).

Whilst these are clearly not the retorts I am wondering whether what is seen here is something to do with further refining of the oil produced. If anyone can assist with an explanation I shall be very grateful.

I have now been advised that these are delayed cokers which are used to make coker gas oil and petroleum coke. They are worked in pairs and the derrick structures at the top are for de-coking one side while the other side is in use.
See: en.wikipedia.org/wiki/Delayed_coker