Before joining academia in 2010, Prof. Oriji spent two decades in the international oil and gas industry, working with leading companies such as Halliburton and Baroid, where he advanced from Trainee Drilling Fluids Engineer to Senior Drilling Fluids Consultant. His professional experience spans onshore, swamp, offshore, and deep-offshore drilling operations across Africa and international locations.

At the University of Port Harcourt, he has served in several leadership roles including, Director, Emerald Energy Institute, Head of the Department of Petroleum and Gas Engineering, Assistant Director at the Institute of Petroleum Studies (IPS), and a member of the University Senate. His academic work focuses on drilling optimization, wellbore stability, reservoir analysis, drilling fluid design, and oil and gas production systems.

Prof. Oriji has authored numerous peer-reviewed journal articles, conference papers, and technical publications, contributing significantly to research on HPHT drilling environments, drilling fluid rheology, reservoir engineering, and petroleum production optimization. He has also supervised multiple PhD and MSc theses in petroleum engineering and related fields.

In addition to his academic work, he remains actively involved in industry consultancy, professional training, and petroleum engineering capacity development, supporting drilling operations and oilfield projects across Nigeria.

Prof. Oriji is a Fellow of the Nigerian Institution of Petroleum Engineers (NIPetE) and a Fellow of the Higher Education Academy (UK). He is also a member of the Society of Petroleum Engineers (SPE), Nigerian Society of Engineers (NSE), and the Council for the Regulation of Engineering in Nigeria (COREN).