Discarded crab shells used to replace toxic chemicals

Waste crab shells are being transformed into a product that can replace a variety of toxic chemicals

Spotted: Crab shells are a source of chitosan, a versatile polysaccharide that has numerous uses, including replacing toxic chemicals involved in water purification, plant growth and preserving fresh produce. Now, Tidal Vision, which previously transformed waste salmon skin into “aquatic leather”, is using crab shells discarded from the seafood industry to produce liquid chitosan. 

Tidal Vision uses crab shells discarded by the fishing and seafood industry to produce chitosan flakes that can then be blended into liquids used in various industrial applications. Tidal Vision produces more than 5 million gallons (19,200 metric tons) of chitosan annually at its plant.  

The process is very efficient. To produce 22 pounds of high-performance chitosan solution only requires around 100 pounds of shells. That amount of chitosan can, in turn, produce a chemical to treat about 10 metric tons (or 2,641 gallons) of contaminated water. It’s a very powerful performance. This means that even if the number of crabs harvested by the fishing industry was reduced substantially, chitosan production would still be economical. 

The use of seafood waste to produce chitosan is an example of “green chemistry,” a practice that includes reducing the number of hazardous chemicals, waste and energy used in chemical applications and processes. Tidal Vision founder Craig Kasberg, who grew up in the Alaskan seafood industry, explains that the crab shells are, “an abundant, problematic byproduct that they either had to send to landfills or incinerators. We’re just preventing that. We’re not only taking a problematic waste stream from the industry that I know and love and grew up in, but now we’re able to turn it into something that really does good for the world, that displaces non-biodegradable toxins and heavy metals.” 

It is becoming increasingly common to incorporate a green approach to manufacturing – not only because it is important in reducing carbon emissions, but because it can also be cost-effective. At Springwise, we have seen this in recent innovations such as a fabric made from recycled carbon emissions and a green battery manufacturing process that cuts out the chemicals. 

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