ARS | Publication request: SYNTHETIC- AND BIO-POLYMER USE FOR RUNOFF WATER QUALITY MANAGEMENT IN IRRIGATED AGRICULTURE

Submitted to: International Conference on Diffuse Pollution
Publication Type: Proceedings
Publication Acceptance Date: April 17, 2003
Publication Date: August 22, 2003
Citation: Sojka, R.E., Entry, J.A., Orts, W.J., Morishita, D.W., Ross, C.W., Horne, D.J. 2003. Synthetic- and bio-polymer use for runoff water quality management in irrigated agriculture. Proceedings of the 7th International Specialised Conference on Diffuse Pollution and Basin Management and 36th Scientific Meeting of the Estuarine and Coastal Sciences Association (ECSA), August 17-22, 2003, Dublin, Ireland. p. 3-130 - 3-136.

Interpretive Summary: Low concentrations of synthetic- or bio-polymers in irrigation water can nearly eliminate sediment, N, ortho- and total-P, DOM, pesticides, micro-organisms, and weed seed from runoff. These environmentally safe polymers are employed in various sensitive uses including food processing, animal feeds, and potable water purification. The most common synthetic polymer is anionic, high purity polyacrylamide (PAM), which typically provides 70-90% contaminant elimination. Excellent results are achieved adding only 10 ppm PAM to irrigation water, applying 1-2 kg/ha per irrigation, costing $4-$12 per kg. Biopolymers are less effective, but show promise; they include starch co-polymers, microfibril suspensions, chitin, polysaccharides and protein derivatives. Using twice or higher concentrations, existing biopolymers are approximately 60% effective as PAM, at 2-3 times the cost per kg. A half million ha of US irrigated land use PAM for erosion control and runoff protection. The practice is spreading rapidly in the US and worldwide. Interest in development of biopolymer surrogates for PAM is high. If the supply of cheap natural gas (raw material for PAM synthesis) diminishes, industries may seek alternative polymers. Also "green" perceptions and preferences favor biopolymers for certain applications. More complete history, user/technical information and bibliography are found at .

Technical Abstract: Low concentrations of synthetic- or bio-polymers in irrigation water can nearly eliminate sediment, N, ortho- and total-P, DOM, pesticides, micro-organisms, and weed seed from runoff. These environmentally safe polymers are employed in various sensitive uses including food processing, animal feeds, and potable water purification. The most common synthetic polymer is anionic, high purity polyacrylamide (PAM), which typically provides 70-90% contaminant elimination. Excellent results are achieved adding only 10 ppm PAM to irrigation water, applying 1-2 kg/ha per irrigation, costing $4-$12 per kg. Biopolymers are less effective, but show promise; they include starch co-polymers, microfibril suspensions, chitin, polysaccharides and protein derivatives. Using twice or higher concentrations, existing biopolymers are approximately 60% effective as PAM, at 2-3 times the cost per kg. A half million ha of US irrigated land use PAM for erosion control and runoff protection. The practice is spreading rapidly in the US and worldwide. Interest in development of biopolymer surrogates for PAM is high. If the supply of cheap natural gas (raw material for PAM synthesis) diminishes, industries may seek alternative polymers. Also "green" perceptions and preferences favor biopolymers for certain applications. More complete history, user/technical information and bibliography are found at <http://kimberly.ars.usda.gov/pampage.shtml>.