Radiation Treatment of Wastewater for Reuse with Particular Focus on Wastewaters Containing Organic Pollutants
Closed for proposals
Project Type
Project Code
F23029CRP
1539Approved Date
Status
Start Date
Expected End Date
Completed Date
15 November 2016Description
Chronic shortages of water in arid and semi-arid regions of the world and environmental policy regulations have stimulated the use of appropriate technologies in treating wastewater for reuse, for example, in urban irrigation, industrial uses (cooling, boilers, and laundry), gardens and parks, cleaning purposes, etc. Additionally, wastewater treatment is becoming ever more critical in large industrial centres due to diminishing water resources, increasing water disposal costs, and stricter discharge regulations that have lowered permissible contaminant levels in waste streams. Industrial effluents often carry chemical contaminants such as organics, petrochemicals, pesticides, dyes and heavy metal ions. The standard biological treatment processes commonly used for wastewater treatment are not capable of treating many of the complex organic chemicals that are found in varying quantities in the wastewaters (e.g. persistent organic pollutants, POPs). Radiation-initiated degradation of organics helps to transform various pollutants into less harmful substances or reduced to the levels below the permissible concentrations. Studies in several Member States (MS) have demonstrated the usefulness and efficiency of radiation technology for treatment of different organic pollutants. The lack of comparative data in pilot scale studies using radiation technique (alone or in combination with other methods) is the main problem in further utilization of this method for wastewater treatment. There is a need to study further the radiation effects, reliability and cost on specific group of organic pollutants in cooperation with other stakeholders who are involved in using other technologies.
This CRP was formulated based on the recommendation of a consultants meeting held in 2008 and improved further in communication with external experts, two SAGNA members and discussed and revised in a meeting with the past-congress president of IWA-World Water Congress and a well known international expert from the Institute for Water Quality, Resources and Waste Management of Vienna University of Technology.
The CRP intends (i) to study the effects, reliability and costs of room temperature radiation processing technology and determine the optimized radiation dose and procedures, in combination with other processes, to treat wastewater contaminated with low and high concentration of organic compounds; (ii) to validate analytical methods to characterize and evaluate effects of by-products in treated wastewaters; (iii) to obtain data on radiation method to treat wastewater with different concentration of organic pollutants and compare it with data from conventional and novel technologies; (iv) to develop guidelines for selection of areas where the radiation treatment has high potential for rendering treated wastewater suitable for industrial and irrigation purposes.
The CRP teams envisaged to participate will comprise members drawn from industry (effluent managers), environmental regulatory authorities, and Members of International Water Association (IWA) apart from radiation technology and analytical scientists.
Objectives
To enhance Member States capacity in applying radiation technology in combination with other techniques for improving environmental safety aspects through effective treatment of wastewater contaminated with organic pollutants and support reuse of treated wastewater for urban irrigation and industrial purposes. This is in line with the objective of the project 2.5.2.5 to enhance Member States capacity in applying radiation technology for managing agricultural and industrial waste and effluents and decontamination of biological agents.
Specific objectives
• Study the effects, reliability and costs of room temperature radiation processing technology for specific groups of contaminants and specific application areas where the radiation technology is promising according to the assessment of existing knowledge.
• Assess the analytical methods to characterize and evaluate the effects on micro-pollutant reduction as well as impacts of radiation by-products in treated wastewaters (aquatic eco-toxicity studies)
• Determination of optimized radiation dose and procedures for different application cases, in combination with other pre- and post-treatment processes for contaminated wastewaters
• Develop guidelines for selection of areas where the radiation treatment has high potential for rendering treated wastewater suitable for industrial and irrigation purposes including boundary conditions for successful application.
Impact
The CRP was expected to enhance the capability of Member States in the use of radiation processing technology to treat wastewater contaminated with organic pollutants and support reuse of treated wastewater .
This CRP investigated a wide variety of challenging pollutants in wastewaters originating from opium processing, cork industry, pharmaceutical industries, textile wastes, plastic industries, chemical fertilizers, municipal wastes, etc. The CRP focused on contemporary and emerging pollutants such as antibiotics, antidepressants, pharmaceuticals, soda wastes, reactive dyes, textile dyes, pesticides, oleo chemicals, endocrine disruptors, pathogens, PFOA, and enteric viruses. The ability to address this diverse set of pollutants with one core technology is noteworthy.
The CRP resulted in development and testing of new ecotoxicity assays. The inclusion of ecotoxicity assays in determining the potential environmental toxicity of the radiation technology treated wastewater is also of significance. The rationale for including ecotoxicity as an end-point measurement of radiation treatment of this diversity of pollutants was novel. The choice of a particular ecotoxicity assay was based on the predicted radiation treatment byproducts.
A variety of analytical methods were either adapted during the course of this CRP. These included pulse radiolysis with kinetic spectroscopic detection (for radiation chemistry), mammalian lung 8549 and mouse RAW 264.7 cells (for ecotoxicity measurements), ELISA, ZR-75 cancer cell lines and the yeast two-hybrid assay (for measuring estrogenic activity), analytical techniques (for directly measuring endocrine disruptors) and the DNA comet assay (to visualize microbial DNA damage). In addition to the analytical methods, considerable effort was spent towards designing and fabrication of hardware to facilitate these research needs.
This CRP has allowed for a deeper understanding of the underlying chemistry that is occurring when different type of wastewater is exposed to varying ionizing radiation sources.
There was significant progress made in the conceptual design and specifications of a movable/transportable eBeam treatment plant.
A significant achievement of the CRP is that an industrial plant to treat 3000 m3 of textile dyeing wastewater has been built in China.
Brazil has undertaken a programme to develop mobile electron accelerators to demonstrate on-site treatment of effluents from various industries.
This CRP provided an outstanding opportunity for a number of individuals to be trained in various aspects of irradiation technology. This resulted in several Masters theses and Ph.D dissertations. Developing a deep science talent pool is critical to the success and sustainability of this technology. 64 peer-reviewed publications, 36conference proceedings, 4 patents and invention disclosures, 16 Ph.D. thesis and 20 M.S. thesis were published during the course of this CRP.
Relevance
Industrial effluents often carry chemical contaminants such as organics, petrochemicals, pesticides, dyes and heavy metal ions. The standard biological treatment processes commonly used for wastewater treatment are not capable of treating many of the complex organic chemicals that are found in varying quantities in the wastewaters (e.g. persistent organic pollutants, POPs). Another important problem arising is the increasing presence of pharmaceuticals and endocrine disruptors compounds in municipal wastewater entering into the receiving stream, for which new treatment techniques and procedures are needed to remove excreted drugs before releasing the effluent into public waterways or reuse. There is a need to develop effective and efficient technologies that help to transform various pollutants into less harmful substances or reduce their levels below the permissible concentrations. This CRP is a step in this direction.