[Ryan]

The capital and operation costs are a huge hurtle to overcome for sure, as Burak noted. As well as the regulator requirements on what can be done with the nutrients once recovered.

There are Algal Biofilm systems, where algae grow on a membrane utilizing the nutrients from the liquid phase. The algae is then harvested and land applied. These systems do have mechanical components but generally do not use any additional inputs like polymers.

Where is possible, direct land application of liquid digestate is a simple, and likely more cost-effective solution to recover the nutrients.