供氧方式对SBR法硝化过程控制的影响

采用SBR法对不同供氧方式下硝化过程的控制进行研究，结果表明：在曝气量恒定的条件下，DO和PH值可联合作为硝化时间的控制参数，但ORP无法单独作为控制参数，在DO恒定的情况下，DO无法作为控制参数；PH值在硝化过程中缓慢下降或趋于稳定，当硝化反应结束时突然升高，因此，PH值可作为硝化时间较好的控制参数；ORP的硝化初期快速升高，然后升高的速度愈来愈慢，直至趋于平稳，对硝化结束的指示作用不是很明显，无法单独作为控制参数；为维持硝化过程中DO的恒定，曝气量将逐渐减小，只要系统污泥浓度和所要控制的DO水平相同，任何浓度的原水在硝化结束时调节的最小曝气量都是相同的，因此，将曝气量下限值的控制方法与PH值控制相结合，可使SBR硝化时间的控制更稳定可靠。

EFFECT OF OXYGEN SUPPLY ON NITRIFICATION CONTROL IN SBR PROCESS

The effect of oxygen supply on DO,ORP and pH variations in the nitrification of SBR process treating petrochemical industry wastewater was introduced in this paper.The control strategies under different oxygen supply conditions were brought out to operate nitrification.The results indicated that under the fixed aeration rate,DO and pH could be used as the controlling parameters of SBR nitrification duration.But ORP variation can't indicate the end of nitrification obviously.Under the fixed DO,pH in the nitrification decreased slowly or stably,then rose suddenly as soon as the nitrification completed.pH can also be used as the controlling parameter of SBR nitrification.ORP went up rapidly in the initial reaction,then rising speed became slower and slower,and tended to be constant.Consequently,ORP variation can't indicate the end of nitrification in SBR obviously and independently.On the other hand,aeration rate decreased in order to maintain DO stable.The demanded lestaeration rate under different influent condition is same only if MLSS and DO level is same.So corporation between the lest aeration rate and pH control can make nitrification time control stable.