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T-00442: Carbohydrates for removing and reusing run-off water nutrients


Water is critical to survival of life on earth; maintaining balance in the water cycle in ecosystems is important to ensure the safety and continuity of both human and animal life. Increased contamination of water bodies has attracted a lot of attention due to ramifications on human health, environment and the economy. According to EPA, phosphorus and nitrogen contamination from farming activities represent one of the major forms of water pollution in United States. Excessive nitrogen and phosphorus in water bodies cause algal blooms resulting in decreased oxygen content and increased levels of toxins. Such conditions are harmful to aquatic plants and fish. Water contamination has been linked to stomach, liver and neurological disorders. Nutrient polluted water can cause blue baby syndrome, a condition in which a baby’s hemoglobin has reduced oxygen capacity; this could cause death if not promptly treated. Several strategies have been employed to curtail nutrient pollution. However, while many water management systems control the amount of run-off water released into water bodies and improve plant yield; they do not eliminate nutrient contaminants. Water treatment systems used to remove these nutrients and provide potable water are capital intensive and require highly trained personnel. At SDSU, researchers are designing alternative water treatment systems that minimize cost of purification, enable farmers and industries to efficiently remove nutrients from water and reuse the extracted nutrients for agricultural activities.


Researchers have adapted polysaccharide beads to maximize extraction of nitrogen and phosphorus in contaminated water. The approach capitalizes the presence of charged groups in a unique formulation of polysaccharide resin to capture nitrogen and phosphorus. This technology can be integrated into EPA’s Drainage Water Management System to ensure efficient capture of nutrients from run-off water. This will ensure drastic reduction of nutrient content of farm run-off water thereby preventing water pollution. Moreover, the technology can be used for purification of storm water and can be integrated into purification systems used in urban water management systems.


This invention adopts the concept of ‘2Rs’ namely Remove and Reuse; farmers will have the ability to remove nitrogen and phosphorus from run-off water and reuse the beads as supplementary fertilizer. The system enables simultaneous capture of nitrogen and phosphorus, which cannot be done with current purification systems that require stepwise extraction of nutrients.