Dangote Refinery
When fully operational, it is expected to have the capacity to process about 650,000 barrels of crude oil per day, making it the largest single-train refinery in the world.
[2] Nigerian businessman Aliko Dangote unveiled early plans for the refinery in September 2013, when he announced that he had secured about $3.3 billion in financing for the project.
[3] However, after a change in location to Lekki, construction of the refinery did not begin until 2016 with excavation and infrastructure preparation, and the planned completion was pushed back to late 2018.
[4][5] In March 2014, Dangote Group has disclosed award of contract to Engineers India Limited, the state-owned Indian firm for the provision of Project Management Consultancy (PMC) and Engineering, Procurement and Construction Management (EPCM) services for the Refinery and Polypropylene plant.
[7] In July 2022, Dangote - Nigeria's richest resident - had to borrow 187 billion naira (about 442 million USD) at 12.75% resp.
The delivery of the Supersuez tanker OTIS did not take place in the refinery's harbour, but via "Single Point Mooring", a buoy-like floating facility for unloading liquid cargo off the coast.
[16] On 26 June 2024, a minor fire occurred in the refinery with video from the scene showing smoke and flame billowing from one corner of the plant.
Following the NNPC's withdrawal as the sole off-taker, subsidies ceased to exist in Nigeria as marketers had to buy directly from Dangote and sell at cost price, adding their own differential.
[26] In November 2024, it was reported that Dangote was in talks with commercial lenders, development banks, oil traders, and other industry participants to secure funds for crude supplies.
[27] However, investors have expressed concerns over Dangote's ability to secure a steady crude supply and the refinery's profitability due to Nigeria's currency devaluation.
The Nelson complexity index basically increases with the number and capacity of chemical procedures after the distillation, e.g. hydrocracking, NHT, CCR, RFCC, polymerization etc.
The main distilling column in Lekki is the biggest in the world (as of 2022) and with 112.5m height even bigger than the rocket Saturn V or the Eko Tower Black Pearl in Lagos.
[42] In very simplified terms, the sharp edges of the zeolite crystals cut up the molecules of the residue fluid without themselves changing shape.
The cracked compounds are fed to a column that separates them according to their boiling point (and thus molecular length, similar to the CDU).
[42] Because of the geometry of their molecules, cracking of alkanes always means Since in RFCC no hydrogen is added, the outgoing compounds belong mostly to the olefins (ethylene, propylene, butylene, pentylene, hexylene etc.).
- In 2015, the regenerator of an Exxon refinery in Torrance, California, exploded due to lack of maintenance (the expander had worn out, a heat exchanger from a different unit was leaking combustible gases into the system and a catalyst slide valve worked insufficiently after too many years of usage) and incorrect actions after a malfunction occurred (decreasing the steam flow, installing a distance ring and "variance" from standard procedure).
[44] Input: heavy oil from CDU, hydrogen Output: C4...C12 alkanes, fractionated into light and heavy naphtha, jet fuel, Diesel Purpose: breaking molecules longer than 25 carbon atoms into shorter ones Input: propylene, butylene (from RFCC), isobutane Output: isoheptane, isooctane (for blending into gasoline), butane, propane Purpose: merging short hydrocarbons into medium-sized molecules, removing olefins, improving RON (see following line in table) The alkylation process takes place in the presence of an acid - in the Dangote refinery, this is sulphuric acid (H2SO4).
On 22 November 2016, a fire occurred in a refinery in Baton Rouge due to maintenance work on a 30-year-old valve that had to be operated manually.
900 kg of isobutane escaped and formed an explosive gas cloud that ignited at a welding machine that was left switched on (20m away).
[55] In Philadelphia, Pennsylvania, on 21 June 2019, propane leaked from a manifold at an alkylation plant and ignited, resulting in three extremely violent explosions.
[56] Input: heavy naphtha from NHT, hydrogen Output: Toluene, Xylene (high octane gasoline components), hydrogen surplus Purpose: improving the RON of gasoline Before entering the CCR unit, the feed of heavy naphtha has passed through the NHT, and C5 and C6 have been removed.
2005, in Texas City, the distilling column of a isom unit erupted and then ignited, killing 15 employees and injuring 180 people.
2010 the NHT heat exchanger of the Tesoro refinery in Anacortes ruptured, causing an explosion and killing 7 workers.
[71] Input: C9...C24, hydrogen Output: C9...C24, hydrogen sulphide Purpose: removing sulphur and nitrogen components from Diesel Input: Sulphur-rich naphtha from the RFCC or MHC Output: naphtha Purpose: removing sulphur components In the Butamer process (Butane isomerization), butane is therefore converted into isobutane.
In 2019, the world's largest crude distillation column, weighing 2,350 tonnes, was installed in place at the Dangote refinery by a specialist Dutch company.
