Water Supply Vol 4 No 5-6 pp 113–119 © IWA Publishing 2005
Natural organic matter fractionation: XAD resins versus UF membranes. An investigation into THM formation
Emma H. Goslan*, Derek Wilson**, Jenny Banks***, Peter Hillis****, Andrew Campbell***** and Simon A. Parsons******
*School of Water Sciences, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK (E-mail: e.h.goslan@cranfield.ac.uk; s.a.parsons@cranfield.ac.uk)
**Water Quality Technology Development Department, Yorkshire Water, Western Way, Halifax Road, Bradford BD6 2LZ, UK (E-mail: derek.wilson@yorkshirewater.co.uk; jenny.banks@yorkshirewater.co.uk)
***Water Quality Technology Development Department, Yorkshire Water, Western Way, Halifax Road, Bradford BD6 2LZ, UK (E-mail: derek.wilson@yorkshirewater.co.uk; jenny.banks@yorkshirewater.co.uk)
****United Utilities Service Delivery, Asset Creation - Task Team, Thirlmere House, Lingley Mere, Lingley Green Avenue, Warrington WA5 3LP, UK (E-mail: peter.hillis@uuplc.co.uk; andrew.campbell@uuplc.co.uk)
*****United Utilities Service Delivery, Asset Creation - Task Team, Thirlmere House, Lingley Mere, Lingley Green Avenue, Warrington WA5 3LP, UK (E-mail: peter.hillis@uuplc.co.uk; andrew.campbell@uuplc.co.uk)
******School of Water Sciences, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK (E-mail: e.h.goslan@cranfield.ac.uk; s.a.parsons@cranfield.ac.uk)
ABSTRACT
An increase in reservoir water colour over the last 10 years has been impacting on the ability of water treatment works (WTWs) in the UK to meet THM regulations. The problem is exacerbated in autumn particularly after heavy rainfall. It appears that residual organics are labile precursors to disinfection by-products (DBPs). One WTW was investigated to determine a link between raw water characteristics and reactivity with chlorine. Bulk water parameters were measured but the information obtained was limited. To further characterise the water, samples of reservoir water were fractionated using XAD resins and UF membranes. The resulting fractions were subjected to analysis of dissolved organic carbon (DOC), UV absorbance at 254 nm (UV254), specific UV absorbance (SUVA) defined as the ratio of UV254 to DOC and trihalomethane formation potential (THM-FP). The samples were also characterised using high performance size exclusion chromatography (HPSEC). Both methods of fractionation described here have limitations in explaining the bulk water behaviour. The relationship between SUVA and THM-FP was discussed. HPSEC showed that the size distribution of the resin separated and membrane separated fractions was similar indicating that the molecular weight cut-off (MWCO) of the membranes is not sharp.
Full article (PDF Format)
PAY-PER-VIEW: Buy this article for £20.00 (IWA MEMBER PRICE: £15.00)
|
