The Process and Water Quality Specialists

Advanced Oxidation
  • uv reactors at ocwd
  • uv reactors at west basin
UV Photolysis and UV AOP

UV/photolysis is a process in which compounds absorb photons and the energy released drives oxidation processes induced by light. The photolysis rate of a compound can be estimated based on the compound’s light absorption rate and quantum yield. Some organic compounds, such as NDMA, can be reduced by photolysis alone. The reduction of many other compounds is aided by the addition of hydrogen peroxide to generate hydroxyl radicals in an advanced oxidation process, as discussed below.

Trussell Technologies has developed a novel methodology to compare bench-, pilot-, demonstration-, and/or full-scale results.  It involves a collimated beam test in the Trussell Tech Fabrication Facility with the water associated with a given project to characterize UV reactor performance under ideal conditions, resulting in a linear log-removal versus UV dose curve for a constituent of interest.  By conducting experiments on the same water for the same constituent at the pilot-, demonstration-, or full-scale, the UV dose achieved in the reactor can be determined.

In the UV/Hydrogen Peroxide (UV/H2O2) process, the photolysis of hydrogen peroxide generates hydroxyl radicals, which oxidize target compounds. Many compounds are not amenable to UV/Photolysis but can be readily degraded using advanced oxidation processes, including such compounds as 1,4-Dioxane, MIB, Geosmin and pharmaceuticals and personal care products (PCPPs). Advanced oxidation processes (AOPs) are an attractive technology because the reaction rate of target compounds with hydroxyl radicals is often several orders of magnitude higher than with any conventional oxidant.

Hydraulics represents a key factor affecting UV processes.  Trussell Tech has developed an innovative approach to tracer studies that can be applied to evaluate UV reactors at the pilot-, demonstration-, and full-scale to account for the effects of varying hydraulic conditions from laminar flow to turbulent flow that may be experienced in practice depending on the situation.