Nigerian billionaire Aliko Dangote's group says it owns the world's biggest construction fleet

Dangote Industries has bought 4,000 more pieces of construction equipment to expand its refinery at Lekki, taking its fleet to 6,500 machines, including 330 cranes. Devakumar Edwin, the group's vice president for oil, gas and fertiliser, said that makes it the largest construction fleet owned by any company in the world.

He made the claim to newspaper editors touring the refinery in Ibeju-Lekki on Friday. The machines will be used to double the plant's capacity to 1.4 million barrels a day, a target set for 2029 that the company wants to reach sooner.

Aliko Dangote decided early on not to hire a main contractor. International firms had quoted fees of about 12.5% of the refinery's estimated $19.5 billion cost, roughly $2.5 billion, just to design the plant and supervise its construction, Edwin said.

He told Dangote it would be "madness" to pay a contractor that much for design and supervision alone. Dangote, he said, pointed to a plaque on his desk that reads "Nothing is impossible."

The group set up Dangote Projects Limited to do the detailed engineering, run the tenders and buy every component directly, down to the nuts and bolts. It then hired contractors for the physical work.

Julius Berger, one of Nigeria's biggest construction companies, reviewed the drawings and declined to build the main process units, telling Dangote it did not have the capacity, Edwin said. It built 43 of the roughly 127 auxiliary structures instead, including canteens, control rooms and fire stations. Dangote bought 2,563 machines to handle the rest, which at the time made the group the second-largest owner of construction equipment in the world.

Hiring foreign engineering, procurement and construction firms would have cost even more, Edwin said, because they ship their machines in and out of the country and charge the client for the wear. When Dangote built its Apapa sugar refinery in 1998, Nigeria had only two large cranes, each able to lift 150 tonnes. The Lekki project needed a crane rated at 5,000 tonnes, one of two in existence, and the group hired it.

The expansion will reuse much of what the first phase built: a granite quarry with capacity of 10 million tonnes, 82 concrete batching plants, 203 transit mixers, a private port, a plant producing oxygen and welding gas, and housing for 50,000 workers. Edwin said that should cut both the cost and the time of the second phase.

Basic engineering is finished and detailed engineering is almost done, he said. Most of the equipment has been ordered, and the main contracts have been signed with advance payments made.

Proceeds from the refinery's share sale, which is seeking 2.15 trillion naira, about $1.6 billion, and closes on Oct. 13, are earmarked for the expansion.

The Lekki plant was designed to process 650,000 barrels a day and is now running at 700,000, Edwin said, which makes it the largest single-train refinery in the world. Dangote is also planning a 700,000-barrel-a-day refinery in Kenya. With both projects complete, the group's refining capacity would reach 2.1 million barrels a day.

Dangote is Africa's richest person, worth $51.3 billion according to Forbes.