MSc Internship: Optimization of thermophilic blackwater treatment for recovery of biofertilizers and energy

Type of project: MSc internship

Duration: > 5 months (could be discussed) start from March 2026 or later

Location: Wetsus, European Centre of Excellence for Sustainable Water Technology, Leeuwarden, the Netherlands

Salary: The maximum Wetsus allowance for this internship is 425 € per month. Grant holding students (i.e. Erasmus or other) receiving financial support of less than 425 € per month can apply for a top-up supplement to the maximum allowance.

Introduction:

Efforts to address soil deficiencies and improve global food production have resulted in a heavy reliance on mineral fertilizers. Human feces and urine contain essential nutrients such as carbon, nitrogen, phosphorus and potassium which are crucial for plant growth. Fortunately, anaerobic treatment of concentrated source-separated blackwater under thermophilic conditions is already shows promise for effective COD removal and biogas production, along with pathogen elimination for enhanced safety of nutrients and biosolids during reuse.

Thermophilic treatment of blackwater, at 55°C, is a stable process that has been previously pilot tested under the H2020 Run4Life project. Already, COD removal (~70%) and methanization conversions (~60%) comparable to those reported during mesophilic treatment have been achieved while operating at higher organic loading rates (OLRs) and shorter sludge and hydraulic retention times (SRTs and HRTs). Phosphorous was largely retained in the sludge, while nitrogen and potassium was present in the effluent.

Now, we will optimize operating conditions for (hyper)thermophilic anaerobic treatment, as enhanced hydrolysis should allow for long-term operation at even higher loading rates and shorter retention times, without compromising on effluent quality. Also, there is need to investigate alternative products, preferably separate CNPK nutrient recovery streams as single nutrient agricultural inputs are more beneficial.

Your tasks:

• Operation of thermophilic anaerobic reactors: Wastewater quality analysis (Microwave digestion along with ICP-OES, TOC analyzer, Ion chromatography, Hach Lange kits)
• Data analysis

Your profile:

• Currently enrolled in Master’s studies
• Background in Environmental engineering or biotechnology, or related fields
• Good practical and experimental experience
• Good communication skills in English.
• Currently studying in the Netherlands or has citizenship from an EU country

What we offer:

• A position at a leading technology institute with a multidisciplinary team and an international environment.
• Opportunity to learn while building sustainable solutions for a circular economy.
• Close guidance via weekly or biweekly meetings
• Experience the multidisciplinary and collaborative research environmental at Wetsus
• Join a large pool of thesis/internship students in an international working environment
• The maximum Wetsus allowance for this internship is 425 € per month. Grant holding students (i.e. Erasmus or other) receiving financial support of less than 425 € per month can apply for a top-up supplement to the maximum allowance.