Disinfection

1. Description:  Water disinfection refers to the inactivation of microorganisms especially pathogens that cause diseases, which may cause damage to the consumers of water, whose intensity and severity vary depending on many factors including: age and physical condition of an infected person, as well as the type of microorganism causing disease and the intensity or concentration in the water of the infectious agent.

Disinfection is perhaps the most important and most significant treatment in water purification. Although in countries that have good infrastructure in sanitation and water treatment, cases of infectious outbreaks caused by consumption of infected water are very sporadic, however in underdeveloped countries the rates of morbidity and mortality by polluted water with pathogens is still very high and causes millions of victims each year.

2. Ranges of design: water disinfection can be carried out by different processes with chemical agents and/or with physical methods. Each of them has its advantages and its disadvantages and one or another method is used depending on the circumstances:

     a. Chemical methods:

          I. Chlorine and its derivatives.

          II. Bromine and its derivatives.

          III. Iodine and its derivatives.

          IV. Hydrogen peroxide.

          V. Metal salts.

          VI. Acids and alkalis.

          VII. Ozone.

     b. Physical methods:

          I. Ultraviolet radiation.

          II. Heat.

         III. Gamma radiation.

     c. Important factors to be considered in the design:

          I. Contact time.

          II. Concentration and type of bacteria.

          III. Temperature.

          IV. Number and type of microorganisms.

           V. Nature of suspended liquid.

          VI. The suspended fluid pH.

3. Applications: Industrial plants (Metallurgical, chemical, petrochemical, pharmaceutical, etc.).

4. Benefits:

     a. Low cost of operation and maintenance.