A Modeling Approach towards Improving Compliance of Treated Water Quality to Reduce Manpower and Chemicals
In water treatment processes, the individual unit operations are complex, non-linear and poorly understood. Whilst many models have been developed to improve process understanding, these are rarely in a form easily exploited by the control engineer. Attempts to improve the performance of water treatment works through the application of improved control and measurement have had variable success. This paper discusses investigations into the application of feed forward control on the clarification process of a small-scale pilot plant. The application aimed towards maximizing the efficiency of the chemical coagulation process. To achieve this, a simple computer program written in Visual Basic version 6 models to a chief the process operating conditions. Mathematical models based on historical plant data covering 18 months analyzed by stepwise multiple regression analysis. The following parameters were important determinants of coagulant dose and pH control reagents: river turbidity, pH, temperature, total dissolved solids, and plant flowrate. A predictive equation developed from the data, of the form: Al2(SO4)3 (mg/L) = a*Q + b*Turb + c*TDS + d*pH + e*Temp + f. The aim of this model is to provide water treatment operators with a tool that enables prediction of chemical reagents and treatment conditions for selected removal of turbidity, based on raw water quality data. While for adjusting pH, whether lime or soda ash are added, the pretreatment of water supplies involves the use to decrease the acidity, to soften, and to clear drinking water, calcium oxide (CaO), commonly known as quicklime or burnt lime. The addition of lime is with the form: CaO (mg/L) = j + k *pH. And for soda ash sodium percarbonateNa2CO3 the addition form is: Na2CO3 (mg/L) = m + n*pH. The advantages of software program are significant in the operation of water treatment plant. The program designed as an aid, so the user can still customize and optimize the computer suggested design. Users are able to move forward in adjusting or optimizing the design in minutes, which is difficult for manual system. This system was an initial system, many new features and functions have to be added to the program to enhance the functions and make it commercially robust. It concluded that this system is very powerful tool in improving compliance of treated water quality to reduce labor and chemicals and to facilitate the organizations and individuals with better understanding on how their actions can have a direct impact on the treatment.
Alaa Husaeen Wadie,
A Modeling Approach towards Improving Compliance of Treated Water Quality to Reduce Manpower and Chemicals, International Journal of Environmental Monitoring and Analysis.
Vol. 1, No. 5,
2013, pp. 194-202.
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