More Sense – Speciation and optimization of elements in algae biomass cultivation systems for safe sludge management

Project name: Biogas Digestate for Safe Usage in Agriculture

Research specialisation: Future Energy Center

Primary funding organisation: KK-Stiftelsen

Secondary funding organisations: ABB Power Generation, Structor Miljöteknik, Flexiclean, Mälarenergi

Co-operating/Co-production partners: VABB Power Generation, Structor, Miljöteknik, Flexiclean, Mälarenergi

Project leader:   Jesus Zambrano , postdoctoral Fellow

Project period: 20150101-20180101

Funding: 3,7 MSEK

Description of the project

Tomorrow’s treatment requirements include phosphorous, nitrogen and BOD removal down to as low as 0.1 mg/L, 5-10 mg/L and 8 mg/L, respectively. It is also likely that there will be certain demands for the CO2 footprint, energy consumption, nutrient recycling and total mass release of nutrients. Algae cultivation in combination with bacterial treatment could be one kind of biological treatment that could all in one treat the water and give a biomass feasible for biomethane production.

During optimal growth, nutrients, CO2 and light are well balanced.
Yet, the challenge goes beyond maximizing these parameters as energy efficiency is of great importance to our process. Robustness is also sought for. We inoculate algae from Lake Mälaren, which are perfectly adapted for our local conditions. The dominating species after a couple of days of pre-treatment are the green algae Chlorella sp and Scenedesmus sp. The operational questions for the cultivation of
these algae species are: how much CO2 can be utilized by the algae culture, how fast is the nutrient retention and how can light be optimized for these purposes? The laboratory experiments and modeling altogether show very promising results.

Therefore, we propose'the More Sense project for the construction of a 2 cubic meter pilot plant with a control system and LED light where we can research these
findings in a continuous process replica of a full-scale algae production unit. Aside of the hereby described post doc-project and the modeling validation, the More Sense project will provide the entire research group with a pilot plant where continuous experiments can be run and extensive data collection for nutrient, metal, pharmaceuticals, carbon and microbial dynamics can be coordinated between the researchers in the group.

Partner companies are Mälarenergi, ABB Power Generation, Structor Miljöteknik AB and Flexiclean AB. The More Sense project could be the absolute breaking point for the applicability of the algae cultivation method for treatment of wastewater.