Developmental Tests On the Underwater Mining System Using Flexible Riser Concept

An underwater mining system with a crawler based mining machine and a flexible riser system has been conceptualised for manganese nodule mining. The flexible riser system with a single positive displacement pump mounted on the mining machine is different from the rigid riser concepts of the seventies where multiple pumps are mounted at different levels along the riser. The system has been tested for mining operations at 410 metres water depth. Four tests were carried out on this system in the Indian seas. The paper discusses the flexible riser concept, details of the tests carried out and results obtained. Specific details of pumping and maneuverability tests carried out are discussed. Based on results from the tests enhancements proposed for future deep sea mining systems are also discussed