SWEETWATER TECHNOLOGY
MICROFLOC ALUM INJECTION SYSTEM

The Sweetwater Microfloc Alum Injection System is designed to reduce the amount of free phosphorous in the water of lakes and ponds in order to control the growth of algae. Alum (aluminum sulfate) is a water treatment chemical used as a clarifier in processing many public drinking water supplies. On contact with water, alum forms aluminum hydroxide (the major ingredient in Maalox). Aluminum hydroxide is very reactive with phosphorous forming aluminum phosphate which is insoluble in water under most conditions. The phosphorous in aluminum phosphate is unavailable as food for the algae organisms. The Microfloc Alum Injection System meters alum into the water. An air diffuser mixes the alum with the water so that a microfloc of aluminum hydroxide is formed and carried to the surface of the water by the stream of bubbles. The particles in the microfloc are so small that they remain suspended where they can react with phosphorus in the water column. One or more bubblers are strategically placed in the lake to take advantage of natural currents or wind drift to distribute the microfloc throughout the entire lake. The system consists of alum metering pumps that pump the alum from holding tanks through hosing to bubblers on the bottom of the lake. An air compressor pumps air through another hose to the bubbler. The alum tanks, pumps and air compressor can be housed in either an existing building or a pump house built for the purpose. Each system is custom designed for the particular lake or pond and alum injection rates are calculated based upon estimates of the amount of phosphorus in the water. Injection rates are easily adjusted to compensate for increases or decreases in the phosphorus loading throughout the season.