Issues. Issues (cont.) A multiple barriers approach is required to provide potable water

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1 EFFECTIVE TECHNOLOGIES TO PROVIDE POTABLE WATER SUPPLY FOR SANITIZING DAIRY FARMS MILKING EQUIPMENTS D.I. Massé, G. Séguin, L. Masse, E. Topp, F. Malouin, E. Pariseau, L. Ortega PRESENTATION OUTLINE Issues Water supply quality Water quality requirements DFO-AAFC Field and laboratory studies Water treatment technologies investigated Agriculture and Agri-Food Canada and Dairy Farmers of Ontario Results Conclusions Issues Goss et al., evaluated the water quality on 173 dairy farms in Prescott County: 55% Drilled Wells 2% Dug Wells 2% on Municipal Wells 12% on Surface Water Issues (cont.) The Ontario Milk Act requires that all water used for milking equipment sanitation meets the provincial regulatory standard on drinking water quality. PART of the Canadian Milk Quality Program They found that 46% of the water sources were contaminated with E.Coli and faecal coliform A multiple barriers approach is required to provide potable water Keep water contaminants from reaching the water source Adopt water treatment technologies to eliminate the water contaminants Barriers to keep water contaminants from reaching the water source: Wells Siting Construction Upgrades Abandonment 1

2 Barriers to keep water contaminants from reaching the water source: Well or Water Source identification imize activities near the water source Manure spreading Animal grazing Herbicide and pesticide applications Etc. Barriers to keep water contaminants from reaching the water source: When the contamination still persists in the ground and surface water sources - Water Treatment becomes a necessary barrier Objectives of AAFC/DFO Research Project To evaluate the efficiency of different water treatment technologies; On commercial farms In AAFC laboratories To recommend operating and maintenance strategies to provide robust and reliable water treatment technologies Selection criteria for the technologies: Cost Adaptable within the existing infrastructures Ease of operation and maintenance Technical support, service quality Water Treatment technologies selected for the on-farm and laboratory evaluation Physical treatment Membrane Ultra filtration Chemical treatments Chlorination Ozonation Chemical treatment Chlorination Physiochemical treatments Ultraviolet Flocculation 2

3 Pilot Study - Meng Farm 5 cows / tie stall operation Water Diapo Source of Water Forested color bog area Water Characteristics - Meng Farm May 7 Sept. 8 (22 samples) Pathogens in Water Meng Farm May 7 Sept. 8 (22 samples) Parameter Hardness (mg CaCO 3 /l) Pathogens (cfu/1 ml) Total coliforms Fecal coliforms Total solids (mg/l) Dissolved solids (mg/l) Enteroccocci Clostridium p. Yersinia Salmonella s.p. 232 Campylobacter sp Existing Installation: Injection of chlorine Use of Carbon Filters Raw Water Treated Water 3

4 Pathogens in Raw and Treated Water - Farm Meng conc. (cfu/1 ml) conc. (cfu/1 ml) Raw water Treated water Total Coliforms May-7 Aug-7 Nov-7 Feb-8 May-8 Aug May-7 Aug-7 Nov-7 Feb-8 May-8 Aug-8 CHLORINATION Advantages Effective disinfectant Residual disinfectant increases safety Inexpensive and easy to install Disadvantages Difficult to operate accurately Combine with organics to form trihalomethanes Need minimum contact time Corrosive 1% water loss due to the carbon filter UV Treatment Ultraviolet Technologies Typical UV radiation penetrates the cell wall of pathogens Damages the DNA structures resulting in microorganism inactivation (Diapo from Ken Haagsma - Trojan UV) Pilot farm studies with UV Seguin Farm - Spring Water Source 9 cows / free stall Operation Standard UV technology Self-cleaning UV technology 4

5 Seguin Farm - Spring Water Source Water Characteristics Séguin Farm May 7 Sept. 8 (22 samples) PATHOGENS IN WATER Séguin Farm May 7 Sept. 8 (22 samples) Parameter Pathogens (cfu/1 ml) Total coliforms Hardness (mg CaCO 3 /l) Fecal coliforms Enteroccocci Total solids (mg/l) Dissolved solids (mg/l) Clostridium p. Yersinia Salmonella s.p Campylobacter sp. 16 UV PURE Wiper UV lamp Sleeve 5

6 Characteristics Number of lamps Expected lamp life Cleaning Flow rate (L/min) Water temperature ( C). hardness (ppm). UVT (%) UV PURE UV Pure stream 2 1 year Self cleaning (stainless steel wiper) Pathogens in Raw and Treated Water from a Spring - Farm Séguin conc. (cfu/1 ml) conc. (cfu/1 ml) Raw water Total Coliforms Treated water May-7 Aug-7 Nov-7 Feb-8 May-8 Aug May-7 Aug-7 Nov-7 Feb-8 May-8 Aug-8 Case Study: Duffey Farm 95 cows / tie stall Operation Duffey Farm Pond Water Water Characteristics - Duffey Farm May 7 Sept. 8 (22 samples) Pathogens in Water Farm Duffey May 7 Sept. 8 (22 samples) Parameter Pathogens (cfu/1 ml) Total coliforms Hardness (mg CaCO 3 /l) Fecal coliforms Enteroccocci Total solids (mg/l) Dissolved solids (mg/l) Clostridium p. Yersinia Salmonella s.p Campylobacter sp. 28 6

7 UV TROJAN UV TROJAN Contaminated water Lamp Sleeve Characteristics Number of lamps Expected lamp life Cleaning Flow rate (L/min) Water temperature ( C). hardness (ppm). UVT (%) Trojan UVMAX Pro years Manual cleaning (acidic chemical product) 76 1 to 4 C Duffey Farm - Trojan UV Pathogens in Raw and Treated Water from a Quarry - Farm Duffey conc. (cfu/1 ml) conc. (cfu/1 ml) Raw water Treated water Total Coliforms May-7 Aug-7 Nov-7 Feb-8 May-8 Aug May-7 Aug-7 Nov-7 Feb-8 May-8 Aug-8 UV TECHNOLOGIES Advantages Fast acting and relatively low cost technology Safe and chemical-free There is no water wastage It successfully removes pathogens and parasites It requires minimal space No residual effect that can be harmful to humans UV TECHNOLOGIES Disadvantages Requires clear water with low hardness Does not kill microorganisms shielded by suspended solids Need a pre-treatment to removed suspended solids Requires regular maintenance to remove fouling of the quartz sleeve 7

8 Case Study: Mario Laniel Farm 4 cows / tie stall Operation Membrane Technologies Water source Ottawa River Water Characteristics - Mario Laniel Farm May 7 Sept. 8 (45 samples) Parameter Hardness (mg CaCO 3 /l) Total solids (mg/l) Dissolved solids (mg/l) Pathogens In Water - Mario Laniel Farm May 7 Sept. 8 (45 samples) Pathogens (cfu/1 ml) Total coliforms Fecal coliforms Enteroccocci Clostridium p. 16 Yersinia 8 19 Salmonella s.p. 5 Campylobacter sp

9 How Membranes Work Homespring Membrane The pores form a barrier to impurities, while allowing water molecules to pass Membrane characteristics Manufacturer Membrane configuration Pore size (microns) Typical Operating Pressure (PSI) Bacteria Removal (%). feed water turbidity (NTU) Homespring membrane (UF211) GE Water & Process Technologies Hollow fiber.2 nominal.1 absolute 3-1 > ND (Slide from ZENON Environmental Inc.) PATHOGENS IN RAW AND TREATED WATER FROM OTTAWA RIVER - Farm Mario Laniel Membrane Filtration conc. (cfu/1 ml) conc. (cfu/1 ml) Raw water Treated water Total Coliforms May-7 Aug-7 Nov-7 Feb-8 May-8 Aug May-7 Aug-7 Nov-7 Feb-8 May-8 Aug-8 Advantages: Easy to install and operate No chemical added to the system Improves water characteristics (taste and smell) High removal efficiency of pathogens Membrane Filtration Disadvantage: Only the milkhouse water Needs pretreatment to avoid membrane fouling with highly turbid water COAGULATION-FLOCCULATION TECHNOLOGY Pre-treatment that changes the characteristics of turbid water and makes it suitable for UV, Ultra-Filtration and Chlorination treatments. No water supply during backflush (cleaning cycle) Water wastage exceeds 2% 9

10 Coagulation/flocculation process Al 3+, Fe 3+ Bühler Farm 1 cows / free stall Operation Raw Water Coagulation Flocculation Creek Water - Bühler Farm Water characteristics Bühler Farm May 7 Sept. 8 (23 samples) Pathogens In Water - Farm Bühler May 7 Sept. 8 (23 samples) Parameter Hardness (mg CaCO 3 /l) Pathogens (cfu/1 ml) Total coliforms Fecal coliforms Total solids (mg/l) Dissolved solids (mg/l) Enteroccocci Clostridium p. Yersinia Salmonella s.p. 4 Campylobacter sp

11 System FLOC 1 Treats up to 9 Imp. gallons/day 9-1 imp gallons per batch 2 to 2.5 hours per batch Raw Water Bühler Farm Creek Water Secondary treatment Flocculation Chlorination Treated Water Turbidity removal by coagulation/flocculation May 7 January 8 September 8 Pathogens in Raw and Treated Water from a Creek - Farm Buhler conc. (cfu/1 ml) conc. (cfu/1 ml) Raw water Total Coliforms Treated water May-7 Aug-7 Nov-7 Feb-8 May-8 Aug May-7 Aug-7 Nov-7 Feb-8 May-8 Aug-8 System FLOC 1 Advantages High removal of turbidity Low maintenance High removal of pathogens Reduction of dissolved organic Disadvantages Only a pretreatment High coagulant product cost Coagulant dosage (hard to calibrate) Floc settling time Lost of water (about 2% each batch) Need space 11

12 Ozonation Technology - Laboratory evaluation Ozonation Technology Ozomax Inactivation of Pathogens with O 3 Total coliforms E. coli (CFU/1 ml) (CFU/1 ml) Time (min) Time (min) OZONATION Advantages Effective disinfectant No wastewater Good removal of pathogens and organic compound Environmentally friendly OZONATION Disadvantages Human safety concern Higher capital cost than UV or chlorination CONCLUSIONS Can lead to toxic bromate if bromide is in water 12

13 Conclusions When the milking equipment washwater is contaminated with pathogens, a multibarriers approach should be considered. Reduce contamination at the source Well identification Select a water treatment technology that is compatible with the farm water characteristics Conclusions (cont.) Chlorination is appropriate with: Ground water Surface water having a low organic content Conclusions (cont.) Standard UV technologies efficient with low turbidity and low hardness water Conclusion (cont.) Membrane technology (Zenon) has worked well with a water having an average turbidity below 1 NTU New UV technologies with mechanical device to eliminate sleeve fouling are more robust and are appropriate with low turbidity water with high hardness Conclusions (cont.) Coagulation / Flocculation is recommended as a pretreatment for highly turbid water prior to the use of: Chlorination Ultraviolet Membrane Ultra-Filtration Conclusion (cont.) Access to potable water for sanitizing milking equipment will: Allow dairy farmers to comply with regulations Maintain consumer confidence in milk quality Maintain a strong dairy sector 13

14 Acknowledgements Farms involved in this project Bühler Farm: Emil, Walter & Willie Bühler St-Onge Farm: Mario and Renée St-Onge Mario Laniel Farm Yves Laniel Farm Innocent Meng Farm Félix and Jean-Marie Duffey Farm Ferme Séguin: Roger Séguin Tony Baas Farm Communication Plan - Scientific papers - Conference proceedings - Final reports for DFO management Board - Articles for Milk Producer Magazine - Fact sheets QUESTIONS? 14