Clean coal developer White Energy said it formally completed the deal with BHP this week.
Under the deal, Billiton Marketing Holding BV has provided White with a $US35 million, seven-year unsecured convertible funding facility to be used in a global rollout of White Energy's patented coal technology.
BHP Billiton Marketing AG will act as White's exclusive marketing agent for export coal produced via White Energy's upgrading coal process.
White managing director John Atkinson said BHP's marketing expertise would help generate interest in key export markets for White's cleaner product.
White is the exclusive worldwide licence holder of the Binderless Coal Briquetting process that reduces the moisture content of low-value coals while significantly upgrading the energy content.
The company is currently constructing a plant in Indonesia under a five-year joint venture with Thiess subsidiary PT Thiess Contractors Indonesia.
It is also looking to deploy the technology in various other markets including China, other Asian markets and the United States.