Study of Free Chlorine Degradation in the Drinking Water Distribution Network Finally to Maintain Water Quality in the Network

Jean-Pierre BEYA Dibue, ISTM/ Kinshasa, INSTITUT SUPERIEUR DES TES TECHNIQUES MEDICALES UNIVERSITE DE KINSHASA, Kinshasa, DEMOCRATIC REPUBLIC OF CONGO (jean-pierre.beya@unikin.ac.cd)

The drinking water distribution network can be considered as a true reactor where water and its container (pipe) are the site of physicochemical and biological interactions. Tap water can have a very different quality to that from the production plant. The parameters that influence the quality of the water in the network are numerous; we can cite: the pH, the temperature, the dissolved oxygen, the oxidizable organic matter and the nature of the construction materials of the water pipes.

In fact, the chlorine used as a disinfectant and an index of water quality in the water distribution network decreases as one moves away from the water treatment plant.

The main purpose of this study is to know how to reduce the amount of free chlorine in the network to maintain constant water quality according to water purification standards. Thus we used the 1st order Kinetic Equation of the form C_t=C₀e^-Kt ; C_t: Concentration of free chlorine at time t, C₀: initial concentration of free chlorine, t: time, K: chlorine degradation coefficient , component of two coefficients such as K=K_b+K_w. K_b: chlorine degradation coefficient in the body of water, and K_w: chlorine degradation coefficient on the walls of the water pipe.

The resolution of this equation makes it possible to determine the quantity of free chlorine, index of water quality, at each point of the network and to calculate the distance of rechlorination or re-rechlorination on the distribution network in the event that the quantity of free chlorine is below the standards.

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Short Biography of Presenting Author

• Professor at the Higher Institute of Medical Techniques of Kinshasa
  
• President of the environment and sustainable development NGO "HORIZON VERT"
  
• Focal point in the DRC of the pan-African agency Water, Sanitation, Africa (EAA)
  
• Professor at the Higher Water School of the University of Kinshasa