DESOZONE Ozone Based Odor Control System

DESOZONE Packaged Ozone Based Odor Control Systems

The DESOZONE system can deodorize 250 to 20,000 m3/h of air from industrial facilities and municipal sewage plants. The system is a complete packaged unit that includes: the blower, washing system with packing, recycling pump of wash water solution (if necessary with chemicals), ozone mixing devices, ozone generator and control panel.

DESOZONE Technical Specifications
DESOZONE Process Diagram
DESOZONE System Photos
DESOZONE English Unit Data Sheet in PDF for Download

General Information

A serious problem for sewage plant operations is the generation of foul smelling odors, especially when they are located within a residential area. Studies have shown that air pollution from odors is the greatest problem that these installations must deal with and for which they receive the most complaints from the local population.

The substances responsible for the odors in the vicinity of treatment plants are generally gaseous inorganic products or highly volatile organic compounds. The inorganic substances are mainly the result of biological activity in the sewage treatment process, the latter are often caused by the presence of industrial wastes in the sewer. Compounds such as mercaptans, skatoles, aldehydes, ketones and inorganic acids are recognized as being among the causes of bad- smelling odors at the outlet of sewer lines and in treatment plants. In general these compounds contain nitrogen or sulphur atoms. Ammonia and hydrogen sulfide are considered to be the main causes of foul odors. Hydrogen sulphide is considered to be the main cause when the sewage comes mainly from households. Its presence is related to the onset of putrefaction in reducing environments characterized by low values of the oxidation-reduction potential.

Defining an air washing system requires a precise definition of the quality and quantity of the air to be treated and the size of the particles involved. Significant factors in designing odor elimination system are:

  • type of odor
  • concentration
  • temperature
  • specific oxidizer dose
  • contact chamber retention time
  • wastewater acceptability criteria
  • type of scrubbing system

Regarding the size of particles, there are three forms of micro-pollutants which can cause foul odors:

  • solid: particles from 0.1 to 100 μm
  • liquid: particles from 0.01 to 10 μm
  • gaseous: coming from chemical or thermal reaction.

To eliminate the micro-pollutants in the air, the carrier gas (air) is washed with an oxidizing reagent. The process is called “chemical scrubbing”. The DESOZONE process uses ozone as the oxidizer because it is much more efficient than the other chemical oxidants.

The optimum system involves a basic (sometimes acid) absorption process and oxidizer.
The contact system is critical to assure the correct gas-liquid transfer and chemical reactions. A poor gas-liquid transfer process will prevent complete elimination of the odors.

With an experience base of many deodorization projects already successfully completed, Spartan with our partner Ozono Elettronica Internazionale (O.E.I.) can ensure safe and effective designs for the most complicated systems. The plant configuration uses horizontal scrubbers that are well suited for the most environments.

In the scrubber a diluted caustic soda solution is the washing fluid. This eliminates bad-smelling acid molecules such as hydrogen sulfide and mercaptans. Adding an oxidiser to the scrubbing liquid will also makes it possible to oxidise the other odor-causing compounds at the same time. The ozone containing solution is uniformly distributed in the scrubber using spray nozzles.

Ozone gas at the pressure of the ozone generator is introduced into the scrubber using a static mixer. A special static mixer mixes the oxidizer with the liquid to be oxidized.

The plant is equipped with level controllers (on the scrubbing liquid containment tank as well as the basic solution storage tank) that permit addition of make-up water and prevent the system from running dry.

The pH of the liquid system is controlled by means the pH probe and its signal is transmitted to the dosing pump which maintains the pH at the desired control point.