Singapore engineers turn shrimp shells into low-carbon industrial inputs with innovative electrolysis process

Singapore engineers are pushing shrimp shells beyond the category of waste and into a possible source of low-carbon industrial inputs, with Nanyang Technological University researchers developing a multi-stage process that turns crustacean residue into hydrogen, cultured protein and calcium carbonate. For industries under pressure to cut emissions, the appeal is not only that the method recovers value from organic refuse, but that it does so in a way that could reduce reliance on fossil-derived feedstocks and quarried mineral inputs.

At the centre of the approach is electrochemical engineer Li Hong and his team, who have adapted electrolysis to work with biomass rather than water. In conventional systems, electricity is used to split water into hydrogen and oxygen, a power-intensive process that also creates safety challenges because of oxygen handling. The NTU method instead uses the organic fraction of shell waste as the feedstock, which lowers the energy requirement and avoids that oxygen-heavy setup. According to the university, a related hybrid electrolysis route for chitin, the biopolymer found in shrimp shells, has achieved more than 90% yield in converting it to acetate while cutting overall energy use by 15%.

The significance for decarbonisation lies in what comes out the other end. Hydrogen remains central to the clean industrial transition, but today most of it is made from natural gas. That grey hydrogen route is emissions-intensive, while greener alternatives are still relatively costly. NTU’s lab-scale system produced 14 litres of hydrogen an hour in tests reported last year, and the researchers say the process can be considered carbon-negative because it prevents waste from rotting in landfill and displacing emissions-intensive products. The caveat, as ever, is scale: efficiency is still below that of established green-hydrogen technologies, and the economics will depend heavily on electricity prices, waste supply and policy support.

The process also yields cultured protein from the residual biomass. For aquaculture, that matters. Farmed fish are often fed on wild-caught fishmeal, a supply chain that carries its own sustainability burden. By turning shell waste into microbial protein suitable for feed, the system offers a circular route that could reduce pressure on marine resources if it can be produced reliably and at competitive cost.

The third output is calcium carbonate, a material with direct relevance to heavy industry. It is used in cement and other products that depend on mined limestone, one of the many mineral inputs under scrutiny as companies search for lower-carbon alternatives. In a sector where every substitution is weighed for cost, availability and process compatibility, a waste-derived calcium carbonate stream could be attractive if purity and consistency prove robust at industrial scale.

NTU has been exploring related routes for some time. The university has also reported a method for extracting chitin from prawn shells by fermenting them with discarded fruit, avoiding the harsh chemicals and high energy use associated with conventional extraction. That work is especially relevant because, as the university notes, 45% to 60% of shrimp shells are typically discarded as processing by-products. In other words, the feedstock problem is less about invention than logistics: the waste already exists in large quantities, but collecting and standardising it is the challenge.

The broader science around crustacean shell waste is widening. A separate study published in the journal Cell Reports Physical Science this year showed that shrimp shells can be converted into a specialised porous carbon for supercapacitors, underlining how a single waste stream can support multiple industrial applications. Together, these developments point to a growing interest in biomass upcycling as a route not just to disposal reduction, but to materials, fuels and chemical intermediates with lower lifecycle emissions.

Still, the step from laboratory promise to commercial deployment remains formidable. The main costs in the NTU approach are likely to come from electricity and infrastructure, while the commercial case will depend on whether hydrogen, protein and calcium carbonate can be sold together in a stable market structure. That kind of coupling can improve project economics, but it also ties performance to more than one commodity market at once.

For industrial decarbonisation professionals, that is the essential takeaway. Technologies like this are no longer just about making cleaner hydrogen. They are about redesigning waste streams into integrated production systems, where emissions cuts, material recovery and revenue generation are meant to reinforce one another. Whether shrimp shells become a meaningful industrial resource will depend on scale, cost and certification. But the direction of travel is clear: organic waste is increasingly being treated not as a burden to dispose of, but as a feedstock for the low-carbon economy.