December 2008
ECOSORB® ENGINEERING MANUAL
the conventional “packed bed-type” scrubbers. This offers an environmentally safe solution for the operation of traditional scrubbers because hazardous chemicals no longer need to be handled. When designing a misting scrubber or modifying an existing unit, it is important to pay close attention to the atomized (mist) droplet size. The best droplet size is less than 10 microns. It is not recommended to operate Ecosorb® in a misting scrubber where the droplet size is greater than 10 microns. The smaller droplet size provides higher efficiency rates due to larger surface area and increased velocity. Another advantage as a result of ensuring smaller droplet size is the minimization of liquid waste leaving the scrubber. Finally, droplet velocity plays a large role in the absorption of the malodor into the Ecosorb® droplet. In high-pressure systems, we recommend you operate the nozzles at the highest possible pressure. If you are using air-aspirated nozzles, the highest practical air pressure setting should be used. Important Points Ecosorb® is often specified in a retrofit as the primary scrubbing solution and therefore as a replacement to the common but more hazardous chemicals. Whether you are retrofitting existing equipment or fitting new equipment, it is important to pay attention to several points: 1. In a retrofit, regardless of what had or is being used as the current scrubbing solution, the chamber and equipment must be purged with clean water until the pH of any liquid within the system is between 5 and 8. Ecosorb® works outside these pH parameters but with reduced efficiency. 2. Ecosorb® must be delivered in droplet sizes below 10 microns. However, if too much vapor is present, the droplets will join and form larger droplets thereby reducing the efficiency of Ecosorb®. This makes selection of the correct nozzle size and pattern important. The nozzles can be installed in a radial (Christmas tree) pattern, concurrent or in a counter-current configuration. The best pattern is countercurrent, as this allows maximum impact with the malodor particles. 3. Media or baffles within the chamber can cause condensation and decrease efficiency. These (if practically possible) should be removed. 4. Since we are dealing with nuisance odor control, success is measured by a reduction in odor level. The reduction of certain gases can be monitored using proper instrumentation. Some modern “hand held” portable units, particularly those that use a “CITY®” sensor, are able to register the changes reasonably accurately. 5. Contact time is important for Ecosorb® to work effectively on some gases. Therefore, one needs to maximize the gas contact time within the system. We recommend a minimum contact time of five seconds. This can easily be accomplished by fitting the discharge duct with a small, slender, secondary vessel of plastic construction before release to the atmosphere.
Section 4: Odor Control Equipment
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