Performance Characteristics Of Pond Aeration Devices

Abstract

ABSTRACTA study was made of the performance characteristics of various pond aeration devices in order to identify an effective system to use in the culture of Macrobrachium rosenbergii. Initial screening work was conducted in the laboratory and examined several porous sparger type devices and a jet exhauster system. Comparisons were made on the basis of the overall volumetric oxygen mass transfer coefficient, aeration efficiency and economy of operation. A sparger type aerator constructed using DuPont's Viaflo tubing was found to be the best candidate at this point.Work subsequently shifted to the pond site where the laboratory candidates were tested along with some larger mechanical aerators and several types of jet exhausters and eductors. Comparisons were made on the basis of the oxygen transfer capability, economy of operation, initial capital cost, and maintenance requirements. Six ponds, ranging in size from 0.03 ha to 0.17 ha, were in operation and stocked with prawns of various sizes from post‐larvae to adults.A mechanical entrainment device called an Air‐O‐Lator turned out to be excellent from an oxygen transfer standpoint and would be a good choice for pond aeration except where water depth is less than 0.7 m. The sparger type aerators constructed of Viaflo tubing were the most economical to operate but encountered a maintenance problem due to algae growth. The exhauster and eductor type devices transfer large amounts of oxygen, but require a lot of energy to do so. Overall economics show the Air‐O‐Lator and Viaflo about equal in total cost with a slight advantage to the Air‐O‐Lator because of its superior maintenance record.