ABSTRACT
As well as being transported via advection and dispersion , chemical substances may undergo a wide variety of chemical, physical, and biological transformation processes (see Chapter 2), which must be accounted for in the transport equation s. To deal with this, the advectiondispersion equation is extended with a reaction term r:
(13.1)
where r = the rate of change in dissolved or particulate concentration due to physical, chemical or biological reactions [M L-3 T-1]. This one-dimensional Equation (13.1) can, for example, be used to calculate the evolution of the chemical concentration of a degradable pollutant in a river downstream of an industrial wastewater discharge.
