Study On Testing Method Of The Oxygenation Capacity Of Blast Aerators And Its Influence Factors In The Process

Aeration system is one of the core technology units in sewage aerobic biologicaltreatment, which is the main energy consumption unit of sewage biological treatmentprocess, its power consumption accounts for about50%of the total energy consumptionin the sewage treatment plant to60%. Therefore, reduce the energy consumption ofaeration units become the key of energy saving in the sewage treatment plant. But atpresent our country in the quality control, management and application aspects ofaerators still exist many problems, especially the lack of standardized product testingmethods and product management systems. Meanwhile, because people have the lack ofsufficient knowledge about aerators’ oxygenation capacity, resulting in there is certainblindness in the aspect of selection, design and application about aerators, leding to thelarger degree of a energy waste in the actual project operation. For this purpose, thisthesis from the perspective of saving energy and reducing consumption in the sewagetreatment, study to establish suitable for China’s national conditions of sewage aerobicaerators performance testing methods, thereby establish the relevant sewage treatmentblast aerators product performance controlling of local standards, in order to lay thefoundation for establishing related specifications of energy consumption for sewageaerators and quality management system of aerators. The main research conclusions areas follows:(1) Study on the test method of oxygenation capacity of universal sewage treatmentblast aeratorsThe study on the digesting and absorbing the international mature, advanceddetection methods, and determined the precision test method of oxygenation capacity ofuniversal sewage treatment blast aerators. Under the condition of normal water depthand air flow in sewage treatment plants, the method for plate aerator and tubular aerator,the KLa20calculated value of repeat experiment test and its mean error are far less thanthat of national urban construction industry standards《CJ/T3015.2-1993: Oxygentransfer measurment of aerators in clean water》specified in the error level.(2) Study on the response duration control in the test of oxygenation capacity ofuniversal sewage treatment blast aeratorsThrough a study of response duration optimal control in the testing of oxygenationcapacity of aerators under non-steady state conditions, by using the method of error analysis and standard deviation analysis, from the perspective of mass transfer theoryanalysis and practice prove that the3.912/KLa can serve as the best control condition forthe reaction duration of aeration, then carried out the application research of3.912/KLaas control reaction in aeration oxygenation test, Finally determines the3.912/KLa canserve as an effective and reliable estimate reaction diachronic method, the controlmethod saves test time while the test results error is small..(3) Study on key influence factors of oxygenation capacity of blast aerators in thetesting processReference to the above research results, by studying on the key influence factors ofoxygenation capacity of blast aerators in the testing process, explicit the variation ofaerators’ relevant performance indicators and influence degree. Through the influence ofair flow rate on oxrgen transfer performance indexes was found that: in theexperimenttal water depth range of3.0~6.0m, with the increased amount of aeration,the standard oxygen transfer rate (SOTR) increased gradually, but theoretical powerefficiency (E) and standard oxygen transfer efficiency (SOTE) reduced gradually.Through the influence of water depth on oxygen transfer performance indexes wasfound that: keeping the air flow rate constant, the standard oxygen transfer rate (SOTR)and standard oxygen transfer efficiency (SOTE) increased gradually with the increase ofwater depth. Meanwhile, within the scope of3.0m to6.0m water depth, theoreticalpower efficiency (E) presented increasing trend with the increase of water depth.(4) Study on sewage treatment blast aerators product performance control localstandards (draft)Through the key performance indicators of aerators, study to determine thestandard oxygen transfer rate (SOTR), theoretical power efficiency (E), standard oxygentransfer efficiency (SOTE), specific standard oxygen transfer efficiency(SSOTE) andresistance loss(RL) as the limited indicators of oxygenation capacity for sewage disposalblast aerators product performance control local standard, and made sure its limit.