The aim of this subproject is to develop quality guidelines and advanced water treatment steps for the healthy reuse of the water produced within the LOTUSHR project. By relating the health risks of the produced water qualities to the quality needed for different reuse purposes, treatment schemes and guidelines can be formulated by which safe reusable water is ensured.
Depending on the type of water (re)use, different water quality requirements are of importance. For instance, drinking water will require higher quality as compared to irrigation water. In general, removal of well-known contaminants, such as disease-causing micro-organisms (pathogens), toxic heavy metals and organic micro-pollutants (e.g., pharmaceuticals) may be needed for healthy re-use. Lately, increasing attention is given to the risks of antibiotic resistance when re-using waste water.
Since the discovery of antibiotics in the late 1920s, human beings have incorporated them to many aspects of our day to day lives. Eventually, antimicrobials found their way into our streams, rivers, lakes and soils which has led to the emergence of antibiotic resistant bacteria. Conventional water treatment technologies are generally not efficient in removing antibiotics and resistant organisms. Antibiotic resistance will receive special attention in our project.
LOTUSHR offers a unique sequential treatment environment that will make safe reuse possible. This research project will determine which uses are compatible with the produced water qualities and explore further advanced treatment to expand reuse possibilities. By doing so a water treatment scheme can be devised that ensures safe re-usable water.
The research will focus on a holistic assessment of LOTUSHR technologies for the removal of health-related contaminants. Based on this information, advanced treatment steps will be developed that can further remove specific contaminants of concern to increase the scope of water reuse options. To ensure safe and healthy reuse, the water qualities produced by LOTUSHR technologies will be used in quantitative microbial and chemical risk assessment methods. Altogether the collected information will contribute to the formulation of Water Reuse guidelines and Water Safety Plans.
To ensure that pathogens, heavy metals, organic micro pollutants and antibiotic bacteria are effectively removed from the water during treatment, the focus will lie on water treatment technology development. The magnitude of infection (or illness) will serve as an indicator to determine performance of water treatment technology or define the reuse potential of treated water.
Specific attention will be given to the type of water reuse and the related water quality requirements. The ruse of water is governed by the risk various contaminants through different exposure routes; i.e., the way people come into contact with the water depends on the activity. A health risk assessment will include exposure routes, both for microbial and chemical contaminants, and dose-response relationship.
Risk assessment traditionally is performed using individual contaminants but the focus here is to identify key reference indicators in each contaminant group and adopt a consolidated risk assessment approach for all contaminants. This holistic risk assessment approach will be able to show us what treatment technologies are required to achieve safe reusable water per specific purpose.
Additional, tertiary treatment steps might be required in addition to LOTUSHR technologies to ensure water safety, technologies that will be explored are advanced oxidation steps, such as ozone or peroxone treatment, electrocoagulation, membrane technologies such as nanofiltration and reverse osmosis, and UV based systems.
By adding additional, or tertiary treatment technology we are able to further reduce any potential risks of the produced waters and expand on the reuse options. Tertiary treatment can be based on advanced oxidation systems, membrane technologies or UV systems. To assess the health risks of pollutants, different model contaminants will be investigated for their survival and behaviour in LOTUSHR technologies. The risk assessment method that will be used is known as “Health Impact Assessment”.
New Delhi frequently suffers from water shortages during the dry season. It is during these periods that most of the water from the Yamuna River is actually wastewater coming the city’s drains. Safe water reuse benefits the local population, agricultural and industrial sectors directly and could restore polluted rivers. The guidelines and technology that will be created are shared with stakeholders and can be used in other mega cities that suffer from similar environmental threats.
Safe reuse of effluent
By developing strict guidelines for water safety and quality, water reuse becomes a reality. Through matching water safety and quality to its intended use, additional treatment steps can be proposed. This makes local treatment and reuse possible which will have a positive effect on the city’s water balance.
Source of income
Increasing the availability of safe water will immediately reduce the costs related to water shortages, reduce water related health effects and improve commercial activities that rely heavily on water. By locally treating water up to the quality that is needed, societal costs for the production of safe water becomes more balanced.
Knowledge creation & dissemination
Our goal is to create strict water treatment guidelines that match water reuse options to the health and quality requirements of the produced waters. These guidelines can be used by stakeholders and will be applicable for other water reuse projects thereby ensuring safe reusable water in future water projects.
The developed guidelines will be linked to the quality of the produced water in the LOTUSHR pre-treatment step (project 2) and the two selected nutrient removal technologies (Vital Urban Filters and Photobioreactor) with its intended use. When needed, additional treatment processes can be added to ensure sufficient water with superior quality that can be safely used. Our technology has the following features:
- Stringent quality and safety water reuse guidelines for mega cities around the world
- Water treatment technology is linked with the quality that is required
- Tailor made water treatment processes offset societal cost of potable water production
COLLABORATION & PARTNERS
The project is a collaboration between the Indian and Dutch research institutes. The Indian side is represented by The Energy and Resources Institute, National Environmental Engineering Research Institute and Indian Institute of Technology Delhi. On the Dutch side by Delft University of Technology and IHE Institute for water Education.
Our contributing partner is Het Waterlaboratorium, which offers us their expertise on water safety and quality monitoring.
All our partners can be found here.