The OBI nickel-cobalt mine deep-sea landfill project in Indonesia utilizes a 1000mm diameter steel-plastic composite pipeline, pioneering the use of large-diameter pipelines for long-distance mining in the deep sea. The OBI nickel-cobalt project—deep-sea landfill pipeline project—is one of the 20 major "Belt and Road" projects in Zhejiang Province in 2019. Located in South Halmahera Regency, North Maluku Province, Indonesia, the project has a total investment of US$700 million and commenced production in 2020. Utilizing the abundant laterite nickel ore resources and mature hydrometallurgical technology of OBI Island, Indonesia, the project constructs and operates a high-pressure acid leaching (HPAL) nickel-cobalt smelting plant and auxiliary facilities, with an annual production capacity of approximately 240,000 tons of nickel-cobalt intermediate products.