Problem & solution

PORTABLECRAC has explored for the first-time different strategies for the scale-up of the electroregeneration of spent AC, an emerging alternative to thermal. Electro-regeneration was expected to be competitive from an environmental point of view but economic feasibility could not be ascertained due to the lack of embodiments with actual industrial potential.

Thermal regeneration of spent AC at large industrial furnaces is the state-of-the-art solution to enable its reutilisation. However, it is not cost-competitive for plants < 20 tons or for those located in remote regions. As an example, plants in Portugal recur to full replacement of the spent AC due to the long cost associated to transporting the spent AC to the closest thermal regeneration plant, which are located in Italy and Belgium. In the EU alone, 85,000 tons of exhausted AC are disposed to landfill every yearby water treatment plants due to the intrinsic limitations faced by thermal regeneration as the only available solution.

After 3 years of intense development, ENVIROHEMP has designed, built and operated a large prototype for AC electro-regeneration (technology named PORTABLE-MT), focused on providing a cost-competitive service to virtually any AC filter size existing in the industry. The novel features of this prototype include:

• First-of-a-kind portable solution for electro-regeneration of spent AC
• End-to-end modular system reaching Metric Tons per day in a single plant
• Highly automated operation by qualified Envirohemp’s technicians

DEMOs with actual spent AC enabling the regeneration of up to 2.5 tons in only few hours of operation. The degree of regeneration achieved is totally comparable to what a thermal regeneration plant can offer nowadays. Additionally, the following benefits have been validated on the basis of independent LCC and LCA analysis:

Economic Key Value Proposition	– Regeneration savings: 0.85 €/kg vs. 1.05 €/kg (vs. termal regeneration) – Fast investment pay-off from 1,600 AC tn/yr (NPV=0 by year 5)
Environmental Key Value Proposition	– GHG reduction of 45% vs thermal regeneration – 95% single score improvement vs landfilling

Potential industries to use the ENV’s prototype for electroregeneration

Considering the AC quantity and lifetime of AC, the drinking water treatment sector industry looks the most feasible to regenerate AC with Portablecrac systems given that the AC quantities are higher and the average lifetime is shorter. In this scenario, PORTABLE-MT is the only prototype that could offer a feasible service to regenerate AC from large or small filters. The environmental benefits of regenerating the AC from small filters is much higher, given that 14-18 tons are currently being replaced by virgin AC and landfilled every 3-5 years.

As a conclusion, it can be said that PORTABLE MT is superior to all other prototypes produced within PORTABLECRAC project in terms of cost-efficiency and has great potential for fast market uptake either as a product or as a service.