Study On Efficiency Evaluation Of Biological Activated Carbon And Carbon Exchange Mode In A Water Plant

With the general application of the advanced treatment process in Shanghai,especially the application in the water plants which use the raw water from the YangZi River,nowadays Shanghai has a capacity of water supply of 11 million cubic meter per day?those data based on the plants use YangZi River?,from which 40% use advanced treatment process while 60% use routine process.Treated water from the advanced treatment plants has a better water quality in comparison with those use routine process,which shows a more pleasant Order and Taste and a higher removal rate of trace organic substances.But problems are also met in the application of the advanced process,e.g.the lack of the experience of the rule of the Carbon Filter,the lack of the lose efficacy of Activated Carbon in the process,and the expected life span for the Activated Carbon,and how to use recycled carbon.Therefore it's a problem for us to think of how to design and manage the process.And the most urgent problem for the water supply enterprises is how to optimize the utilization of Activated Carbon resource and how to raise the efficiency of the whole process.This paper illustrates the utilization of O3+BAC advanced treatment process in one plant,shows the efficiency of the Activated Carbon and the way to regenerate and change the Carbons in the filter,which is practice-oriented and valuable to the management in similar-process-used plants.The result of the research was as follows: As time goes by,the efficiency of the five Carbon Filters from the first manufacturing line decrease gradually.The COD_Mn Level of effluent of the five Carbon Filters was between 0.91¹.0mg/L,the removal rate of COD_Mn was between 16.7% 24.2%,UV₂₅₄ level was between 0.012 ⁰.014cm-1,the average removal rate of UV₂₅₄ of Carbon Filters was between 12.5%²5%.And the level of the removal rate of TOC of Carbon Filters was between 10.3%¹7.0%.And through data comparison,the adsorption value of the Activated Carbon does not represent and explain the function of the removal of the organic substances,so it could not measured as an important controlling parameter.The invalidity parameter should be determined from the function in the process.When the Activated Carbon act as an adsorption media,the iodine value is relatively important,when it decrease to 500-600mg/L,changing of new Carbon might be taken into consideration.But when the Activated Carbon is used for an biological process,the removal of COD_Mn is relatively more important than iodine value,and when the removal rate of COD_Mn is lower than 10%,changing of new Activated Carbon could be taken into consideration.Now,heating is the most used method to.After regenerating the Carbon which used for five years by heating,the performance of the adsorption revives well.The iodine value of the regenerated Carbon is946mg/g,while Methylene blue value is 196 mg/g,and 70% is receivable.But the Mechanical strength and the size are a little decreasing,but the regenerated Carbon still Satisfy the requirements of the parameters in the process.