Determination of some discharge parameters of horizontally discharged cold-dense wastewaters

Thermal pollution is defined as increase or decrease in temperature of an aquatic environment which may be ocean, lake or river by human influence. a common cause of thermal pollution is the use of water as a cooling and heating system by power plants, liquefied natural gas (lng) re-gasification terminals and industrial manufacturers. one of the important sources of thermal effluents is cold water discharges, which are mainly originated from lng re-gasification terminals from open cycle heating units. cold water can be frequently discharged into coastal waters. due to its high density, cold water discharge is a kind of negatively buoyant jet. because of some undesired effects of cold water on receiving water species, should be discharged properly into the marine environment with a high level of initial dilution. some discharge parameters of horizontally discharged cold-dense wastewater such as initial dilutions, impingement points were determined in a laboratory system using circular port in this study. to determine the behavior of the cold-dense wastewater (wastewater jet geometry) rhodamine b as a colorant was added to the wastewater. a high-resolution camera was used to take snapshots of the colored cold-dense wastewater. temperature changes (dilutions) in the cold-dense wastewater jet centerline were detected with sensitive thermal probes. to gain different densities, three discharge temperature differences were used as -3 °c, -5 °c and -7 °c. according to the results of this study, it was determined that the cold water discharges behaved like a negative buoyant jet. in addition, it was calculated that the averages of the normalized impingement point and initial dilution of the cold water were found 2.333 and 0.491, respectively.