Use Case 5: Wastewater treatment
Different locations within the Use Case:
The monitoring and control of waste-water treatment use case will take place in different locations:
- In Chennai the LOTUS sensor will be used in an algal-based wastewater treatment plant;
- In Warangal the LOTUS sensor will be used in an innovate wastewater treatment plant.
- Algal-based wastewater treatment has been confirmed as a suitable way to treat wastewater and to produce valuable substances, but so far has only been investigated experimentally investigated; therefore, the operating parameters are yet to be optimised.
- Activated sludge wastewater treatment is an established technology that is used world-wide, but still has a large potential for improved energy efficiency and reduced pollutants in the outflow especially in high load conditions.
Scope of the use case:
The scope of the use case is to employ the LOTUS sensor to improve the operation of wastewater treatment plants. The following two subcases will be considered:
- Activated sludge treatment
- Algal-based wastewater treatment
Key aims for improving water quality for irrigation networks:
- Achieve the desired effluent quality through highly efficient day-to-day operation;
- Reduce as possible the operational cost of the wastewater treatment processes and in particular the demand for electric power;
- Monetise the wastewater in the form of bio-fuels and fertilizers in order to make the best use of wastewater as a resource;
- Maintain the effluent qualities for all weather conditions for varying influent qualities.
How LOTUS will improve monitoring and control of algal-based wastewater treatment plant:
The approach will rely on two main steps:
- Validation of the LOTUS sensor as a tool to monitor the level of contamination at the different stages of the depollution process;
- Use of the sensor as a tool to optimize the performance of the process, in terms of cost and depollution quality.
- Up to 3 sensors each will be integrated into the experimental facilities at NEERI (National Environmental Engineering Research Institute) in Chennai.
- Sensors will be integrated into experimental facilities at NITW (National Institute of Technology, Warangal, Telangana) in different locations.
- NEERI Chennai fabricated one vertical and one horizontal reactor of 10 and 20 l for algal-based wastewater treatment studies.
- NEERI, Chennai has placed an order for two raceway ponds (5000 liters and 1000 liters) with paddle wheels for pilot-scale algae-based wastewater treatment:
- The parameters pH, temperature, TDS (Total Dissolved Solids), salinity, nitrogen, phosphorus, and D.O. (Dissolved Oxygen) will be measured online.
- With the goal of advanced control of the plants at NEERI, simulation studies are performed at TU Dortmund.
- A suitable model of the process has been identified from the literature;
- A state estimation scheme (Extended Kalman Filter, EKF) has been developed and tested in simulations.
- Currently TUDO and NEERI are communicating to decide on the actuations that will be implemented at the plant.
- The ultimate goal is the implementation of a nonlinear model predictive control scheme of the process based upon TUDO’s nonlinear NMPC technology.
- An experimental facility is being set up for biological wastewater treatment at NIT Warangal for evaluating the LOTUS sensor and its use in closed-loop control algorithms with the goal to improve the efficiency of the process. Nitrate and DO will be controlled at certain locations.
Outcomes of Use Case 5:
- Sensors will enable to demonstrate and improve the efficiency of innovative water treatment plant,
- Treated water can then be safely rejected in the natural environment.