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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
              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.

            • News
              Reuters, March 15, 2018

              The nation’s largest refinery finished a planned overhaul of some of its units on Wednesday which had cut production in half for part of the first quarter, according to sources familiar with plant operations.

            • News
              LUKOIL, November 30, 2017

              LUKOIL recently announced that the company has made the final investment decision on the delayed coker complex at its Nizhny Novgorod refinery. The complex includes the construction of the delayed coker unit itself, the diesel hydro treatment unit, the gas fractionation unit, the sulfur and hydrogen production units, and other infrastructure.

            • News
              Gazprom Neft, July 27, 2017

              Construction of a delayed coking unit (DCU) has now begun at Gazprom Neft’s Omsk Refinery. Annual raw material consumption at the complex will be two million tonnes. The DCU is set to become one of the largest facilities of its kind in Russia

            • Partner Content

              InVista is a lightweight, hand-held ultrasonic in-line inspection tool (intelligent pig) capable of detecting pipeline wall loss and corrosion in unpiggable or difficult-to-inspect pipelines. The pipeline geometry inspection data captured by the InVista tool is exceptionally powerful when combined with the LifeQuest™ Pipeline fitness-for-service capabilities, providing an integrated solution set for the pipeline industry.

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              Essar, July 25, 2017

              Essar Projects India Ltd. (EPIL), a leading EPC contractor, today announced the successful testing and commissioning of the Coke Drum Structure Package (CDSP) for Bharat Petroleum Corporation Limited’s Kochi Refinery (BPCL-KR). The contract value of this package is Rs. 645 crores.

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