Chemistry, Materials & Packaging
The Humble Crab Shell Could Upend a Variety of Polluting Industries — Starting with Wastewater

Clean water’s dirty secret

The United States alone processes about 34 billion gallons of wastewater every day — globally, the wastewater treatment market reached $250.38 billion in 2021 and is expected to reach $ 462.49 billion by 2030. You might think that public health concerns would’ve necessitated a number of safe methods for treating and disposing of wastewater around the world — but you’d be wrong: Conventional, non-biodegradable treatment products utilize cationic (positively charged) metals such as aluminum and iron to remove anionic (negatively charged) contaminants in water. These traditional treatment solutions also contain petroleum-derived polymers such as polyacrylamides, which are known to be carcinogenic to the human body if not adequately filtered out.

These metals and polymers end up in the wastewater sludge — the majority of which is applied directly to the soil or landfilled, posing risk of ecosystem contamination. Improper coagulation can also result in higher concentrations of remaining metals in treated drinking water, which has been linked to negative health impacts on the brain.

Enter Tidal Vision — a startup founded by an intrepid creative thinker who found a potentially game-changing, circular solution being tossed out at a local fishery.

From crab to treatment plant: The evolution of chitosan

Chitosan — the main component of shrimp and crab shells — is known for being non-toxic, fully biodegradable and the world’s only natural cationic biopolymer. Thanks to a thriving crab industry, chitosan is the second most common biopolymer in the world — and until recently, no viable methods existed to extract chitosan from underutilized crab shell waste.

For many years, chitosan has been used to bind sediment in industrial and construction runoff. Its mainstream adoption in municipal wastewater treatment and its many other applications was undeveloped until Tidal Vision founder Craig Kasberg dusted off an old book in an Alaskan fishing cabin.

Kasberg started off in commercial fishing in Alaska, where he noticed tons of wasted crab shells being landfilled or illegally dumped in international waters. He found a book on chitosan sitting on a shelf in his cabin — the beginning of his quest to utilize fishing waste for good.

Kasberg’s first incarnation of Tidal Vision upcycled crab shells and other common forms of fishery waste such as salmon skin into textiles — on a mission to give sustainable fisheries, which are often at an economic disadvantage relative to their competitors, a leg up by creating an additional revenue stream from the sale of their waste products.

Fast-forward a few years and Tidal Vision has pivoted away from textiles and become the only vertically integrated chitosan solution manufacturer in the world, and the only commercial-scale chitosan producer in the US. With a process of cheaply and sustainably manufacturing chitosan from upcycled crab shells, Tidal Vision embarked on a journey to liquify it for water-treatment applications. The result is an effective natural coagulant and flocculant that’s price-competitive with mainstream treatment solutions.

“[Kasberg] adopted first-principles thinking and went back to the raw basics on how to manufacture chitosan from crab shells,” Peter Moore, SVP of Sales and Marketing at Tidal Vision, told Sustainable Brands™.

The company’s proprietary, zero-waste manufacturing process produces chitosan in a liquid form that is non-hazmat and cheaper than the metal coagulants traditionally used in wastewater treatment plants. In the wastewater treatment process, chitosan’s net-positive charge acts like a magnet, naturally binding to negatively charged pollutants in contaminated water for easy filtering. Following its use, only clarified water remains.

“Our goal is to have mass adoption of chitosan globally to offset synthetic chemicals and provide positive systemic change,” Moore says.

Tidal Vision’s Tidal Clear™ solution has been officially certified by NSF International for sale to water treatment facilities — marking an industry shift towards prioritizing healthier, more sustainable solutions. With Tidal Clear, the chitosan left in the sludge is non-toxic, biodegradable, and — unlike sludge treated with conventional metals and synthetic materials —has an additional benefit to ecosystems: A bio-elicitor, chitosan tricks plants into thinking they’re being attacked by insects, leading to higher yields and stronger plants.

Chitosan poised to disrupt countless industries

Industry demand for cationic biopolymers is huge, Moore says, and goes well beyond the scope of water treatment.

“[Chitosan] is a fertilizer enhancer, it's a fungicide, it's a growth promoter,” he said. “Those are huge industries; and we are strategically poised to significantly offset the chemicals used in those markets within the next 12-24 months.”

Tidal Vision is investing heavily in new hires, studies and certifications to help it bring its chitosan-based water-treatment solution global. Other markets are also on the horizon, such as bioplastics, pool maintenance, agriculture, food preservation (another Tidal Vision product, Game Meat Protector, takes advantage of the cationic nature of chitosan to discourage pathogens from binding to the surface of foods, thus expanding shelf life) and back to textiles —chitosan can replace metals and synthetic materials currently used to give fabrics antimicrobial, moisture-wicking and flame-suppressant properties.

Chitosan can also add value for meat and dairy processing plants, whose wastewater is laden with valuable fats and proteins; the biodegradable nature of chitosan means these valuable materials could now be recovered — an impossibility using metal-based coagulants and flocculants, Moore said.

Next steps

Though a full LCA and impact statements aren’t yet publicly available, Tidal Vision is hiring an impact analyst to craft a public-facing report. The study will include the net-positive impacts of the product as it relates to metal and synthetic offsets, waste reductions, emissions avoidance and more.

“This is something we’re going to broadcast and be extremely transparent about,” Moore said. “[Emissions reduction] is a huge positive that chitosan is creating for the environment; so that’s something we want to measure down to the milligram.”

Tidal Clear™ is being piloted in a few municipalities, he said. They're under NDAs, so details can’t be divulged; but Moore expects pilots to reach conclusive results within months. The company’s two US plants are ready to deliver chitosan products to more municipalities eager for sustainable water-treatment solutions.

“There are multiple municipalities across the United States that are very keen to find more sustainable solutions that have positive, systemic impacts on the environment,” Moore said.

A public-facing impact assessment for several Tidal Vision products will be available in the third quarter of 2022.