Crude distillation is considered a primary processing operation in refineries throughout the world. Every barrel of oil fed into these plants is charged to the crude unit for initial separation of a range of petroleum products. Global crude distillation capacity increased by 2.82% (just over 907K b/cd), to bring the worldwide total to over 88.9MM b/cd, from Jan. 2012 to Jan. 2013 with an average increase of 0.89%/y worldwide over the past five years. Operation of the crude distillation unit (CDU) will have an impact on the yield and quality of every single product leaving the refinery, and therefore, it will be beneficial to refiners to make the successful design and operation of this unit a top priority. For the purpose of this publication, the CDU will be considered as one unit comprising two components: an atmospheric tower and a vacuum tower.
Crude distillation technology is considered an open art/off the shelve technology by many, however, there are still licensers for this technology in Foster Wheeler, KBR, Shell, Technip, and Uhde. The competition exists for peripheral technology associated with CDU like advanced process controls, simulators, internals, etc. Most of the industrial advances involving the CDU are associated more with operations and efficiency improvements including the processing of heavier types of sour crudes, mitigating corrosion and fouling, and improving energy efficiency. Furthermore, the shale oil boom in North America is resulting in refiners in that region looking to orient existing CDUs to handle these light crudes that can present their own unique challenge especially in terms of fouling due to the paraffinic nature of these crudes.
The key areas of focus are processing of heavier types of sour crudes, meeting market conditions, and energy efficiency. With the reducing supply of conventional light and sweet crude, refiners have to investigate best practice to process heavy sourer crudes even with increased risk of fouling and corrosion in the process equipment. These are major problems as they can reduce throughput and at worst, cause plant shutdown. Avoiding such problems requires proper maintenance by close monitoring of process, simulations to predict problems, modifying of equipment and process, and even replacement of equipment for smooth operations. While processing such unconventional crudes, the refiners also need to meet market standards and satisfy government regulations which further impacts margins. Therefore increasing energy efficiency is another area of investigation for CDU using advanced heat integration and advanced efficient internal mechanisms/hardware. CDU is one of the most energy intensive process and with new concerns about CO2 emissions, energy slashing methods are investigated. The crude distillation section also features the latest trends and technology offerings, including:
- An updated look at global crude supply and demand fundamentals and what impact increased output and usage of opportunity crudes and shale oil is having on the global market;
- Combination of KBR’s crude distillation technology with its ROSE solvent deasphalting process;
- Updated information on Shell’s bulk CDU process;
- Wide ranging APC, simulators, analyzers, and related CDU technology for unit operation and optimization;
- Increasing importance of the desalter for processing heavy/opportunity crudes and shale oil;
- Feed flexibility for refiners to process various types of crudes within the same unit;
- Maximization of desired products from CDU (cat reformer feed, diesel, and VGO);
- Energy optimization techniques;
- Methods and technologies for overcoming CDU corrosion and fouling issues;
- Vacuum tower revamp options; and
- A discussion of the latest patent applications and research papers regarding crude distillation technology, including using ultrasonic waves to improve distillation yield; treating crude oil with a microbial strain; corrosion mitigation methods when processing highly acidic crudes; increasing production from the vacuum tower; energy optimization of the CDU using various models and simulations; and more.