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Overview of Delayed Coker Unit (DCU)

A Delayed Coker Unit is a type of coker that utilizes multiple pairs of drums working in tandem, sometimes as many as eight at a time, to recover specific elements from feedstock residues, tar pitch, and residual oils. This is done through a process called cracking, and involves using heat and pressure to break down long chains of hydrocarbons into shorter chains. The process begins in a furnace, where the crude is heated to its thermal cracking temperature and continues as the fluid is moved through the transfer line into a pressure vessel known as a coke drum. 

The coke drum separates lighter vapors out of the crude, including hydrocarbon gases, naphtha, and light and heavy gas oils. The vapor is then removed for further refinement. The leftover material is called coke and is similar to charcoal. Once the drum is full of coke, the coke is cut out from the drum using high pressure water cutters. To do this, the drum must be taken offline. With a delayed coker unit, production is simply shifted to the next drum. This allows a facility to have one coker online continuously, avoiding unnecessary downtime. 


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            News related to Delayed Coker Unit (DCU)
            • News
              Exxon Mobil Corp., October 31, 2018

              ExxonMobil said today that it has started operations of a new unit at its Antwerp refinery in Belgium to convert heavy, higher-sulfur residual oils into high-value transportation fuels such as marine gasoil and diesel.

            • News
              ADNOC, September 5, 2018

              ADNOC Refining, a subsidiary of the Abu Dhabi National Oil Company (ADNOC), recently announced it has successfully completed the commissioning of a specialized coker unit, as part of its Carbon Black and Coker Project. With this, ADNOC will extract the maximum value from ‘bottom-of-the-barrel’ heavy oils and slurry, as it delivers on its aggressive Downstream strategy.

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