Obiettivo To design and build a full scale commercial test rig to enable the accurate determination of the oxygen transfer coefficient for any aeration device. The test rig will enable, for the first time, accurate calculation of the oxygenation capacity and aeration efficiency of installed aeration equipment at sewage works.Following analysis of the aeration test data, an optimal operating strategy can be formulated which may allow energy savings of up to 15% to be made.The test rig has proved a technical success and been used or five tests during the demonstration phase of the project.Based on these tests, the annual energy may be estimated at 1.3 GWh and the payback time at 7 years.The results of the tests show that for surface aerators the possible energy saving are in the line of the prediction. For surface aerators there are two variables, depth of immersion and number of aerators in operation. An optimum, least energy cost, operating strategy can therefore be identified and the results have shown that the original planned savings of 15% were realistic.For diffused air system however, once the plant has been built, there is only one variable : the air flow. Energy savings in these treatment works are made as a result of a well designed oxygen control system. The potential for saving energy as a result of an aeration test in diffused air plants is small (about 3%).Consequently, the future of the aerator test rig will depend on the numberof sewage treatment plants built with surface aerators, eg oxidation ditches.The test rig comprises all of the equipment necessary to carry out the determination of the oxygen transfer coefficient and efficiency of operational aerators by using steady and unsteady state techniques.The equipment is housed on two vehicles. The Chemical Mixing vehicle contains a 10 m3 tank for preparation of sodium sulphite solutions; a 1 m3 tank for cobalt chloride solution preparation; and the necessary pumps and pipework to fill prepare and add the chemical solutions. Provision is also made for handling the dry chemicals.The other vehicle, a Mobile Data Laboratory, houses a laboratory/workshop and the data logging and processing equipment. It is planned that up to 12 dissolved oxygen probes will be services by 4 small slave radio transmitter units which transmit data to a master received radio housed within the vehicles and linked directly to the computer facility. Processed data can be viewed on a screen or printed out.After filling of the aeration pool to be tested with clean water, the oxygen probes are displayed at all major locations in the pool. The pool is depleted in O2 by the sulphite-cobalt solutions. The aeration device is set to work under given conditions. The O2 level increase rate in the basin is recorded and the transfer coefficient, KLa, calculated. The equipment is repeated for different working conditions of the aeration device. From the results of 5 to 10 tests an energy efficient operational strategy for the aeration device is developed. Fifteen aeration pools are expected to be tested each year. Life of test rig is estimated at 10 years. A yearly average energy saving of 1 500 000 kWh and a simple payback time of 4 years are expected.Monitoring is an essential and innovative part of the project. It concerns essentially accurate and reliable oxygen transfer measurements. Programma(i) ENG-ENALT 2C - Programme (EEC) of demonstration projects relating to the exploitation of alternative energy sources and to energy saving and the substitution of hydrocarbons, 1983-1985 Argomento(i) 1.4 - TREATMENT OF WASTE Invito a presentare proposte Data not available Meccanismo di finanziamento DEM - Demonstration contracts Coordinatore Thames Water Utilities Ltd. Contributo UE Nessun dato Indirizzo Spencer House Basingstoke Road RG2 0JN Reading Regno Unito Mostra sulla mappa Costo totale Nessun dato
