Efficient Waste Water Treatment.
Clean drinking water is an essential need of mankind. Often surface water like rivers or lakes is used as drinking water source. To prevent these resources from pollution the effective treatment of waste water is a must. For example in China 75% of discharged waste water is coming from pulp and paper, textile and dyeing industries. To run a waste water treatment plant in the most efficient way certain measurement technologies have to be available. In respect to size of the plant and individual efficiency objective 3 different types of measurement parameters have to be distinguished.Parameters that are essential to ensure the cleaning process on a waste water treatment plant like pH and DO Parameters that shows the efficiency of the plant like BOD and COD Parameters helping to optimize the plant like DO, ammonium, nitrate, nitrite and phosphorous Parameters that are essential to run a waste water treatment plant – pH-value and DO-concentration to run a waste water treatment plant at all the pH-value as well as the dissolved oxygen (DO) content have to be monitored. A stream of inlet water with a pH-value outside of a range from 6.0 to 9.0 will cease the activity the micro-organism needed for the cleaning process. Besides that a pH-value below 6.5 will destroy the concrete of the facilities.During the cleaning process a sufficient amount of dissolved oxygen for growth and metabolism of micro-organism has to be ensured. A DO concentration of 1-2 mg/l is sufficient in a aeration tank. Higher DO-content will not necessarily increase the cleaning efficiency. Blowing air into the aeration tank should be adjusted to that DO-concentration of 2 mg/L, more is just wasted energy.