K. Fitzhenry 1, *, E. Clifford 1, 3 , N. Rowan 2 , A. Stocca 2 , W. Finnegan 1 , X. Zhan 1 1 College of Engineering and Informatics, NUI Galway; 2 Bioscience Research Institute, Athlone Institute of Technology, 3 Ryan Institute for Environment, Marine and Energy, NUI Galway. *[email protected]; www.dairywater.ie Tertiary Treatment Technologies for Water Reuse and Rainwater Harvesting in the Irish Dairy Industry Abstract April 2015 sees the abolition of quotas on milk production which is expected to increase the Irish dairy sector by 50% in the next five years. Dairy produce encompasses a wide range of products including butter, cheese, whey and milk powders for which a considerable amount of water is required. It is used for a wide range of activities within the plant such as steam generation, cooling duties and cleaning in place (CIP) with CIP duties accounting for the majority of water consumption. While water consumption rates have decreased in recent years, fieldwork surveys on Irish dairy plants have revealed that the majority of water utilised outside of food production is not reused. Legislation regarding the discharge limitations of dairy wastewater effluent is becoming increasingly stringent along with initiatives to conserve and reuse water within the industry. The use of tertiary treatment systems; ozone and UV may play a dual role of acting as end-point effluent treatment systems as well as disinfection systems to restore dairy wastewater to reusable CIP standards within dairy plants. In addition, rainwater harvesting also has the potential to decrease water consumption by utilizing on-site stormwater and tertiary treatment technologies. This study will attempt to address those themes. Figure 1. Projected global population growth (U.S. Census Bureau, 2011). Figure 4. Projected milk production increase by 2020 (Irish Dairy Board, 2013). Research Drivers Water Scarcity: By 2030, global water demand will exceed freshwater supply by 40% 1 . Contributing factors include increasing global population (Fig. 1), urbanisation and overexploitation of groundwater. Water consumption efficiency: The Irish dairy industry is inefficient in comparison to other countries. Ireland: 2.5m 3 /m 3 of milk processed 2 Australia: 1.75m 3 /m 3 of milk processed 3 CAP abolishment: Elimination of milk quotas in the Irish dairy sector is expected to expand the industry (Fig. 2) significantly. Legislation: Increasingly stringent legislation (e.g. EU Water Framework Directive) as well as industry expansion may enforce higher quality standards for dairy wastewater effluent. Research Focus The aims of the study are to investigate three areas of water/wastewater treatment within dairy plants and wastewater treatment plants (WWTPs) using tertiary technologies; pulsed UV and ozone treatment (Figure 3). Pathogen removal in dairy wastewater effluent will be analysed; the potential for water reuse within the plant via both systems will be evaluated and on-site stormwater will be investigated as potential rainwater harvesting source. Figure 3. Focus of study research areas. Dairy Industry Liaison Preliminary Results Site survey feedback Microbiological Analysis Future Work Figure 1. Projected global population growth (U.S. Census Bureau, 2011). Figure 2. Projected milk production increase by 2020 (Irish Dairy Board, 2014 )4. Figure 4. Nationwide survey of dairy plant sites. • Pathogen removal in dairy wastewater. • Water reuse potential within dairy plants. • Rainwater harvesting via investigation of on-site stormwater catchments. Tertiary treatment technologies; PUV and ozone will be used to investigate: • In order to inform each of the research areas a nationwide site survey was carried out (Figure 4). • Six dairy plants (DP1 – DP6) were visited in total which included liquid milk plants, milk powder production plants and cheese production plants. • Typical survey questions included annual water consumption, water reuse measures, disinfection practices and discharge limitations for WWTPs. • Dairy wastewater samples were also collected for preliminary microbiological analysis. Main findings of the survey highlight; • Rainwater harvesting is not considered a priority is most facilities. • Overall, water reuse does not appear to be widely implemented; DP5 purchased all process water and so had the highest rate of water reuse. Cost appears to be an incentive. • There is significant potential for work on removal of pathogens from effluent wastewaters. • Results suggest dairy wastewater is contaminated with faecal pathogens and would require tertiary disinfection treatment for water reuse purposes. • Fig. 5 illustrates levels of standard bacterial indicators (E. coli and coliforms) in the wastewater samples. The red line indicates the discharge limits for the indicator concentrations in drinking water; 0 CFU/mL. DP2 DP3 DP4 DP6 DP6 1E+00 1E+01 1E+02 1E+03 1E+04 1E+05 1E+06 Total coliforms (CFU/mL) CFU/mL Figure 5. Total coliform and E.coli concentrations of dairy wastewater influent (inf) and effluent (eff) samples. •Identify key pathogens of concern in dairy wastewater effluents. • Compare disinfection technologies for pathogen removal efficiency in dairy processing wastewaters. • Identify potential areas of water reuse within dairy plants by way of tertiary treatment technology. • Investigate the potential of on-site stormwater as potential rainwater harvesting opportunity. References [1] 2030 Water Resources Group (2009). Charting our Water Future; Economic Frameworks to Inform Decision-Making. 2030 Water Resources Group. [2] Geraghty, R. (2011). Benchmarking Resource Efficiency in Ireland’s Dairy Sector. Enterprise Ireland, Dublin 3, Ireland. [3] Barr, D., van Buuren, N. (2013). 2010/11 Australian Dairy Manufacturing Environmental Sustainability Report. Dairy Manufacturers Sustainability Council. [4] Irish Dairy Board (2014). Annual Report 2013. Irish Dairy Board, Grattan House, Mount St. Lower, Dublin 2, Ireland. Acknowledgments The authors would like to acknowledge the funding provided by the Department of Agriculture, Food and the Marine for the DairyWater project (Ref.: 13-F-507).
Ryan Institute Research Day 2015 - Poster presentation: Tertiary treatment technologies for water reuse and rainwater harvesting in the Irish dairy industry.
Apr 14, 2017
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
K. Fitzhenry1,*, E. Clifford1, 3, N. Rowan2, A. Stocca2, W. Finnegan1, X. Zhan1
1 College of Engineering and Informatics, NUI Galway; 2Bioscience Research Institute, Athlone Institute of Technology,
3Ryan Institute for Environment, Marine and Energy, NUI Galway. *[email protected]; www.dairywater.ie
Tertiary Treatment Technologies for Water Reuse and Rainwater Harvesting in the Irish Dairy Industry
AbstractApril 2015 sees the abolition of quotas on milk production which is expected to increase the Irish dairy sector by 50% in the next five years. Dairy produce encompasses a wide range of products including butter, cheese, whey and milk powders for which a considerable amount of water is required. It is used for a wide range of activities within the plant such as steam generation, cooling duties and cleaning in place (CIP) with CIP duties accounting for the majority of water consumption. While water consumption rates have decreased in recent years, fieldwork surveys on Irish dairy plants have revealed that the majority of water utilised outside of food production is not reused. Legislation regarding the discharge limitations of dairy wastewater effluent is becoming increasingly stringent along with initiatives to conserve and reuse water within the industry. The use of tertiary treatment systems; ozone and UV may play a dual role of acting as end-point effluent treatment systems as well as disinfection systems to restore dairy wastewater to reusable CIP standards within dairy plants. In addition, rainwater harvesting also has the potential to decrease water consumption by utilizing on-site stormwater and tertiary treatment technologies. This study will attempt to address those themes.
Figure 1. Projected global population growth (U.S. Census Bureau, 2011).
Figure 4. Projected milk production increase by 2020 (Irish Dairy Board, 2013).
Research DriversWater Scarcity: By 2030, global water demand will exceed freshwater
supply by 40%1. Contributing factors include increasing global population (Fig. 1), urbanisation and overexploitation of groundwater.
Water consumption efficiency: The Irish dairy industry is inefficient in comparison to other countries. Ireland: 2.5m3/m3 of milk processed2
Australia: 1.75m3/m3 of milk processed3
CAP abolishment: Elimination of milk quotas in the Irish dairy sector is expected to expand the industry (Fig. 2) significantly.
Legislation: Increasingly stringent legislation (e.g. EU Water Framework Directive) as well as industry expansion may enforce higher quality standards for dairy wastewater effluent.
Research FocusThe aims of the study are to investigate three areas of water/wastewater treatment within dairy plants and wastewater treatment plants (WWTPs) using tertiary technologies; pulsed UV and ozone treatment (Figure 3). Pathogen removal in dairy wastewater effluent will be analysed; the potential for water reuse within the plant via both systems will be evaluated and on-site stormwater will be investigated as potential rainwater harvesting source.
Figure 3. Focus of study research areas.
Dairy Industry Liaison
Preliminary ResultsSite survey feedback
Microbiological Analysis
Future Work
Figure 1. Projected global population growth (U.S. Census Bureau, 2011).
Figure 2. Projected milk production increase by 2020 (Irish Dairy Board, 2014)4.
Figure 4. Nationwide survey of dairy plant sites.
• Pathogen removal in dairy wastewater.
• Water reuse potential within dairy plants.
• Rainwater harvesting via investigation of on-site stormwater catchments.
Tertiary treatment technologies; PUV and ozone will be
used to investigate:
• In order to inform each of the research areas a nationwide site survey was carried out (Figure 4).
• Six dairy plants (DP1 – DP6) were visited in total which included liquid milk plants, milk powder production plants and cheese production plants.
• Typical survey questions included annual water consumption, water reuse measures, disinfection practices and discharge limitations for WWTPs.
• Dairy wastewater samples were also collected for preliminary microbiological analysis.
Main findings of the survey highlight;• Rainwater harvesting is not considered a priority is most facilities.• Overall, water reuse does not appear to be widely implemented; DP5 purchased all process water and so had the highest rate of water reuse. Cost appears to be an incentive.• There is significant potential for work on removal of pathogens from effluent wastewaters.
• Results suggest dairy wastewater is contaminated with faecal pathogens and would require tertiary disinfection treatment for water reuse purposes.
• Fig. 5 illustrates levels of standard bacterial indicators (E. coli and coliforms) in the wastewater samples. The red line indicates the discharge limits for the indicator concentrations in drinking water; 0 CFU/mL.
DP2 DP3 DP4 DP6 (Inf) DP6 (Eff)1E+00
1E+01
1E+02
1E+03
1E+04
1E+05
1E+06Total coliforms (CFU/mL) E. Coli (CFU/mL)
CFU
/mL
Figure 5. Total coliform and E.coli concentrations of dairy wastewater influent (inf) and effluent (eff) samples.
•Identify key pathogens of concern in dairy wastewater effluents.• Compare disinfection technologies for pathogen removal efficiency in dairy processing
wastewaters.• Identify potential areas of water reuse within dairy plants by way of tertiary treatment
technology.• Investigate the potential of on-site stormwater as potential rainwater harvesting
opportunity.
References[1] 2030 Water Resources Group (2009). Charting our Water Future; Economic Frameworks to Inform Decision-Making. 2030 Water Resources Group.[2] Geraghty, R. (2011). Benchmarking Resource Efficiency in Ireland’s Dairy Sector. Enterprise Ireland, Dublin 3, Ireland.[3] Barr, D., van Buuren, N. (2013). 2010/11 Australian Dairy Manufacturing Environmental Sustainability Report. Dairy Manufacturers Sustainability Council.[4] Irish Dairy Board (2014). Annual Report 2013. Irish Dairy Board, Grattan House, Mount St. Lower, Dublin 2, Ireland.
AcknowledgmentsThe authors would like to acknowledge the funding provided by the Department of Agriculture, Food and the Marine for the DairyWater project (Ref.: 13-F-507).
Related Documents
