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Face scrub, poo pellets & algae trainers: 5 products embodying circular aspirations

Wednesday, 10 April 2019

Circular economy ambitions and announcements have become commonplace but what exactly does this phrase mean in reality?

European Union ambitions and greenwashing to one side, examples are now demonstrating how water companies and manufacturers are teaming up to showcase true closed loop, resource recovery.

From calcite and lime recovery in the Netherlands, through to waste briquettes in Kenya and phosphorus recycling in Denmark; we’ve found five great examples demonstrating that a Circular Economy is more than just a buzzword (or two!).

1. Calcite circular face scrub

Involving utility Waternet, Dutch partnership AquaMinerals and skincare company Naïf, this development could become the face of circular initiatives, quite literally.

Using calcite by-product from drinking water production, a new face scrub is being produced.

Drinking water lime, or calcite (CaCO3), is generated during the drinking water softening process in the form of calcite pellets.

In the Amsterdam-based ‘Calcite Factory’, the factory dries, grinds, sieves and hygienises the sand-free calcite pellets from the softening reactors of drinking water companies. The resulting end-product is a seeding material that water utilities can reuse in their softening operation.

The installation was built by Advanced Minerals, a subsidiary of the British water supply company, SES Water.

A good example of the circular economy, a material is extracted during water treatment, incorporated into a cosmetic product and then, following its use, is returned to the water, to be recovered again.

2. Eco Flame briquettes

A socially motivated company called Sanivation is shaking up how sanitation services are being delivered in developing nations.

The company installs modern “blue box” container-based toilets in people’s homes for free and then charges a small monthly fee to service them.

Collected waste is then transformed into a clean-burning, odourless alternative to charcoal. The final product is sold in supermarkets and returned to the customers under the brand Eco Flame briquettes.

The solution has a two-fold benefit, particularly in countries like Kenya where up to 95 percent of wastewater is not treated before being returned to the environment.

It also helps to reduce deforestation by illegal settlements for logging and charcoal production.

Below is a video showing the process:

3. Humic acid to lime recovery

Dutch water company Vitens continues to play an important role in the circular economy.

After the successful development of humic acid recovery in 2012, known as HumVi, the process has been applied globally since 2014 by German biotechnology firm, Humintech GmbH.

Since then the utility has developed two additional applications for lime: pellets for the agricultural and feed industry. The collaboration has brought together Vitens, Aquaminerals and Agrifirm in the Netherlands to enable a successful market introduction.

The focus was to identify relevant markets for high value products for agriculture, according to Rik Thijssen, manager of business development.

He told Aquatech: “Agriculture is the number one export product in the Netherlands. Vitens extraction areas are mainly in rural areas covered with agriculture activities for decades now. These activities are affecting our soil/water sources due to the extensive use of (chemical) fertilizers and (chemical) pesticides aiming for a maximum yield of crops.”

In the first case, lime pellets are extracted from the water treatment process and used to help manage pH levels in agriculture. Thijssen said the lime particles are demonstrating enhanced slow release properties, compared with traditional sources.

Secondly, lime pellets are being used as poultry feed to replace lime stone particles which were previously imported from France and Belgium into the Netherlands, incurring a higher environmental footprint.

Within several weeks, a third product will be launched. Called FerrEau, this will be the first biological Fe-chelate available in the market, according to Thijssen.

4. Denmark goes circular on phosphorus recovery

In Denmark, a circular approach is being taken on phosphorus. Classified by the European Commission as among the 20 “critical materials”, the non-renewable resource is essential for agriculture and food production.

Partnerships in three plants (city of Herning, Aaby and Marselisborg - city of Aarhus) are enabling phosphorus to be extracted as a side revenue stream from the wastewater treatment process.

The heart of the process involves injecting magnesium chloride to obtain precipitation-crystallization of struvite.

Washed, drained and dried, the struvite is then being sold in the country under the PhosphorCare brand through fertiliser companies.

Furthermore, such commercialisation of struvite as a fertilizer generates revenue, with SUEZ claiming the return on the investment is between five to 10 years.

Such partnerships demonstrate that additional value, besides energy, can be extracted from wastewater treatment plants.

5. Algae trainers

British shoe company Clarks announced that change could be…afoot…in the sustainability of the global shoe industry.

Part of a wider strategy by its company Vivobarefoot to become 90 percent sustainable by 2020, a partnership was signed with San Diego-based Bloom to turn algae from foe to friend.

As part of the process, algae biomass is harvested from freshwater sources to create an alternative to petroleum-based Ethylene-vinyl acetate (EVA), found in conventional flexible foams.

The Bloom process involves harvesting algae before coagulation and then dewatering before drying into an algae biomass. This is then ground to a fine powder and compounded into plastic composite pellets, before being expanded into a flexible foam.

According to the company, a single pair of the Bloom shoes returns 57 gallons of clean water to habitat and reduces 40 balloons worth of carbon dioxide from the atmosphere, per pair.

Galahad Clark, founder and MD of Vivobarefoot described the initiative as a “true revolution for the footwear industry”.