Gates, and the expo itself, remained focused on the need - driven by present and future water shortages and a lack of infrastructure in many parts of the world - for toilets that process human waste without the need for water-fed sewers.
Sanitation technology could save the lives of hundreds of thousands of childrenThomas Peter/ReutersHe declared that "today we are on the cusp of a sanitation revolution" and promised to unveil the most significant advances in the field for nearly 200 years.
Placing a jar of feces on a pedestal next to him, billionaire philanthropist Bill Gates made a plea Tuesday for the safe disposal of human waste as he kicked off a "Reinvented Toilet" Expo in China.
These toilets have an electro-chemical reactor that can break down water and human waste into fertilizer for fields and hydrogen, which can be stored in hydrogen fuel cells.More news: Big retailers gear up for Black Friday
According to the World Health Organization, around 2.3 billion people still do not have basic sanitation facilities such as toilets or latrines.
The former Microsoft chief executive said the next step for the project is to pitch the concept to manufacturers, adding he expects the market for the toilets to be more than $6bn (£4.5bn) by 2030.
"Innovative companies have a golden opportunity to do well by doing good", LIXIL President Kinya Seto said in a statement.
"It's no longer a question of if we can reinvent the toilet and other sanitation systems", he said.More news: These Are The Victims Of The Thousand Oaks Shooting
The Gates Foundation hopes to instal reinvented toilets in schools and apartment buildings until they become cheap enough for individual families to afford.
"China has an opportunity to launch a new category of innovated non-sewered sanitation solutions that will benefit millions of people worldwide". "It's a real win-win", Gates said.
"The value of those outputs exceeds the operating cost", Gates said.
Poor sanitation kills half a million children under the age of five annually and costs the globe over $200 billion a year in healthcare costs and lost income, according to the foundation.More news: Earth's ozone layer is finally healing, UN says
Gates also highlighted some promising human waste tech, including a small treatment plant called an Omni Processor that processes human waste to produce electricity and clean drinking water. "And I definitely never thought that Melinda would have to tell me to stop talking about toilets and fecal sludge at the dinner table".