Nigerian billionaire Aliko Dangote, Africa’s richest man, got rich making and selling cement.

He built cement factories in 17 African countries including his most recent one — East Africa’s largest — about to be inaugurated in Ethiopia, Naija247News reports.

Dangote carefully followed the progress of the Ethiopian plant construction, flying his personal jet to Addis Ababa every two weeks, according to the report. He usually does not spend the night in Addis except maybe one night at the Sheraton Addis after a tiring field visit to the construction site, according to Naija247News.

“Usually he flies back to Nigeria the same day,” said an employee of Dangote Cement Ethiopia.

Dangote Cement Ethiopia is a state-of-the-art cement factory near Muger town, 85 kilometers (53 miles) west of Addis Ababa. The factory occupies 134 hectares (331 acres).

The Ethiopian plant was built by Chinese construction firm Sinoma International Engineering. All the machines were bought from Germany, Sweden and Italy.

Bosnian power company, Energo Invest, built a 57-kilometer power transmission line (35 miles) from the town of Sululta to the project site. ABB of Germany erected the power substation at the factory.

Dangote Cement Ethiopia imported mining equipment that mines limestone and other raw materials from the quarry. It installed automatic truck-loading robots. “We also use robot technology to test the quality of the cement,” said Teshome Lemma, country general manager of Dangote Cement, according to Naija247News.

The company plans to import 500 trucks from China to transport cement including six bulk cement carriers.

The automated truck-loading machine can load nine trucks at a time. It takes a truck 15-to-20 minutes to the factory, load 800 sacks of cement and leave.

The factory has the latest pollution-control technology, Teshome told Naija247News. “The factory is environment friendly. There is no smoke coming out of it.”

Inauguration of the new factory is expected in mid-April. The plan is for cement produced there to hit local markets by early May 2015.

Dangote has cement plants in Senegal, Zambia, Tanzania, South Africa, Congo Brazzaville, Ethiopia, and Cameroon, and cement terminals in Ghana, Sierra Leone, Ivory Coast and Liberia.