Cattle feed and dye membranes win MIT water prize

ENTREPRENEURS who are developing process technologies to remove dyes from industrial wastewater and help reduce methane emissions from cattle have been recognised with prizes from MIT.

MIT’s annual Water Innovation Prize was split between two student-led startups, Symbrosia and SiPure, whose founders each took home US$14,000 in prize money to support the development of their environmental innovations. 

Symbrosia has developed a patent-pending system that symbiotically farms shrimp and produces algae for use as emissions-reducing cattle feed. It is estimated that cattle release around 44% of the world’s anthropogenic methane emissions, but research from James Cook University in Australia has found that replacing 2% of cattle feed with a certain seaweed reduced individual emissions by 99%.

Symbrosia’s system includes a tank for growing the red seaweed A. taxiformis, a tank for growing shrimp, and chambers that move the waste between the two, so that the shrimp waste fertilises the seaweed, and seaweed produces clean, oxygenated water for the shrimp. The only water loss from the system is due to evaporation, MIT News reports.

The team will pilot the technology with industry partners later this year with the goal of placing commercial-scale systems close to farms to sell feed for cattle, and supply shrimp to local consumers. Symbrosia warns that 90% of shrimp is imported to the US and that their farming has been linked to human rights abuses and the destruction of mangroves across tropical and sub-tropical regions.

Meanwhile, SiPure has developed a nanoporous silicon membrane that founder Brendan Smith says can remove 99% of dyes from the wastewater produced by textile manufacturing for around ten times less cost than competing ceramic-based techniques.

Later this year, the company will begin a pilot project at a textile mill in India, purifying up to 100 L of wastewater each day. If successful, the plan is to continue scaling in India and secure 40% of the market by 2025.

The prize is sponsored by market research firm BlueTech Research whose analysts will now consult with the winners.