Analysis of recycled water for reuse
Introduction
Recycled water, also called reclaimed water, is a valuable resource in a world facing water scarcity. Reusing treated wastewater offers a sustainable solution by reducing pressure on freshwater sources. To ensure safe and effective reuse, a thorough analysis of the recycled water is crucial.
https://link.springer.com/article/10.1007/s10311-023-01683-2/figures/4
Types of Water Reuse
There are several types of water reuse, categorized based on the source of the water and its intended use after treatment. Here's a breakdown of the most common types:
|
Type |
Description |
|
Agricultural Reuse |
Treated wastewater used for irrigating crops, orchards, and landscapes. Most common type globally. |
|
Onsite Reuse |
Graywater reused for toilet flushing, laundry, or irrigation within a building or complex. Reduces freshwater demand within the building. |
|
Industrial Reuse |
Treated wastewater used for various industrial processes, including cooling water, boiler feed, and cleaning. Analysis depends on industry. |
|
Potable Reuse |
Highly treated wastewater used for replenishing drinking water supplies. |
|
Stormwater Capture and Reuse |
Rainwater runoff collected, treated, and reused for irrigation, toilet flushing, or other non-potable purposes. Conserves freshwater and reduces stormwater runoff. |
The specific analysis required for recycled water depends on two main factors
- Intended Reuse Application: The type of application will dictate which parameters are most important to analyze. Here's a table summarizing this concept:
|
Application |
Focus of Analysis |
|
Agricultural Reuse |
Salinity, Nutrients (nitrogen, phosphorus), Microbiological quality (absence of harmful bacteria) |
|
Industrial Reuse |
Varies depending on industry. May include specific contaminants, heavy metals, or organic compounds. |
|
Non-potable Urban Use (toilet flushing, car washing) |
Microbiological quality, some basic parameters like turbidity or pH. |
|
Application |
Focus of Analysis |
|
Agricultural Reuse |
Salinity, Nutrients (nitrogen, phosphorus), Microbiological quality (absence of harmful bacteria) |
|
Industrial Reuse |
Varies depending on industry. May include specific contaminants, heavy metals, or organic compounds. |
|
Non-potable Urban Use (toilet flushing, car washing) |
Microbiological quality, some basic parameters like turbidity or pH. |
- Treatment Methods Used: The treatment process the recycled water has undergone will influence which contaminants might still be present. For example, if reverse osmosis is used, heavy metal testing might not be a major concern.
Types of analysis commonly performed on recycled water
Physical characteristics:
- Turbidity: Measures cloudiness caused by suspended particles.
- Conductivity: Indicates dissolved salts and overall water salinity.
- pH: Shows acidity or alkalinity of the water.
Chemical composition:
- Heavy metals: Tests for presence of lead, mercury, and other potentially toxic metals. (Not always necessary depending on treatment)
- Organic compounds: Identifies residual organic pollutants like pesticides or pharmaceuticals.
- Nutrients: Evaluates levels of nitrogen and phosphorus, which can be beneficial for irrigation but harmful in excess.
Microbiological analysis: Perform tests for microbial contaminants such as bacteria, viruses, and parasites. Microbiological analysis is crucial for assessing the risk of waterborne diseases and ensuring public health safety.
Market overview
The Water Recycle and Reuse Market is estimated to be worth USD 16.1 billion in 2023 and is expected to increase at a compound annual growth rate of 10.8% from 2023 to 2028, reaching USD 27.0 billion by 2028. The main influence of the market is the substantial utilization of water recycling and reuse equipment across diverse end-use industries.
Regulations and standards
|
Region |
Description |
Example |
|
European Union |
The EU Water Reuse Regulation (2020/741) establishes a framework for safe water reuse across the member states. It classifies reuse water quality into categories (A, B, C, D, E) with varying levels of stringency based on potential health and environmental risks. Each category outlines specific water quality parameters and mandatory minimum treatment levels. |
- Category A: Highest quality, suitable for irrigation of edible crops after minimal disinfection (e.g., greens, fruits). Category E: Lowest quality, restricted to industrial applications with minimal human contact (e.g., toilet flushing). |
|
United States Environmental Protection Agency (USEPA) |
The USEPA does not have national mandatory regulations for reuse water. However, they provide Guidelines for Water Reuse which offer recommendations for treatment, monitoring, and management practices based on intended use. Many states have adopted or adapted these guidelines into their own regulations. |
- The USEPA framework emphasizes a risk-based approach, tailoring requirements to specific reuse applications. Guidelines address factors like public health protection, environmental impacts, and agricultural suitability. |
|
India |
The National Framework on safe reuse of wastewater by the National Mission for Clean Ganga (NMCG) provides guidelines for reuse in India. It categorizes reuse water based on quality and outlines minimum treatment requirements. The framework also emphasizes adoption of local regulations based on specific water needs and environmental conditions. |
- Similar to the EU, India's framework classifies reuse water into different categories. The framework promotes adoption of advanced treatment technologies for higher quality reuse applications. |
Mandatory and Optional Analyses for Reuse Water
The specific analyses required for reuse water depend on regulations and the intended use of the treated wastewater. However, here's a breakdown of common mandatory and optional analyses:
Mandatory Analyses:
Microbiological: These analyses are crucial for protecting public health and ensuring the water is free from harmful bacteria, viruses, and parasites. Common tests include:
- Total Coliform Bacteria
- coli
- Fecal Coliform Bacteria
Physical and Chemical: These analyses assess various properties of the water to ensure its suitability for the intended use. They may include:
- pH (acidity/alkalinity)
- Electrical Conductivity (EC) (salinity)
- Total Dissolved Solids (TDS) (dissolved minerals)
- Turbidity (cloudiness)
- Chlorine Residual (disinfectant level)
- Nutrients (nitrogen, phosphorus) - especially important for agricultural reuse
Optional Analyses:
- Metals: Depending on the source of wastewater and potential industrial contamination, testing for specific metals like lead, cadmium, or chromium might be necessary.
- Emerging Contaminants: These include pharmaceuticals, personal care products, and endocrine-disrupting chemicals. Testing for these may be required in specific situations or for research purposes.
- Organic Compounds: Analysis for specific organic compounds may be needed if there's a concern about industrial or agricultural runoff in the wastewater source.
- Toxicity Tests: These tests assess the overall impact of the treated water on living organisms, particularly for reuse in sensitive environments like aquaculture.
Eurofins role in analysis of recycled water for reuse
Eurofins, a global scientific leader, can play a crucial role in analyzing recycled water for reuse applications. Here's how their expertise can be valuable:
- Water Quality Testing: Eurofins has extensive experience in testing water samples for various parameters, including physical, chemical, and microbiological contaminants. This ensures that recycled water meets specific reuse standards set by regulatory bodies.
- Microbiological Analysis: Eurofins can analyze the presence of pathogens like bacteria, viruses, and parasites in recycled water. This helps assess the potential health risks associated with reuse.
- Emerging Contaminants: Eurofins can also test for emerging contaminants like pharmaceuticals, personal care products, and industrial chemicals that may not be routinely monitored but can be present in recycled water.
By providing a comprehensive analysis of recycled water quality, Eurofins can help ensure its safe and sustainable reuse for various applications, including:
- Irrigation: Recycled water can be used for agricultural irrigation, reducing pressure on freshwater resources.
- Industrial Processes: Many industries require large volumes of water for cooling and other processes. Recycled water can be a cost-effective and sustainable alternative.
- Non-Potable Uses: Recycled water can be used for toilets, laundry, and other non-drinking purposes, reducing reliance on potable water supplies.
Overall, Eurofins' expertise in water quality testing and analysis can play a significant role in promoting the safe and responsible reuse of recycled water, contributing to a more sustainable water management approach.
References
- https://eurlex.europa.eu/legalcontent/EN/TXT/PDF/?uri=CELEX:32020R074
- https://nmcg.nic.in/writereaddata/fileupload/32_SRTW%20Framework_Final_23_11_2021%20(1).pdf
- https://www.epa.gov/sites/default/files/2019-08/documents/2004-guidelines-water-reuse.pdf
- https://www.marketsandmarkets.com/Market-Reports/water-recycle-reuse-market-
- Tortajada, C. (2020). Contributions of recycled wastewater to clean water and sanitation Sustainable Development Goals. Npj Clean Water, 3(1), 1-6. https://doi.org/10.1038/s41545-020-0069-3
