不同季节中水回用于景观水体的藻类增长模拟

Algae Growth Simulation of Reclaimed Wastewater Recycled to Landscape Water Body in Different Seasons

文章基于WASP的富营养化模型,模拟了在各季节中水回用于城市景观水体时,不同水质和换水周期条件下叶绿素a峰值和平衡浓度的变化情况。模拟结果表明:(1)在中水水质和换水周期一定时,水华风险在夏季最大,春秋季次之,冬季最小;(2)在夏季和春秋季节,叶绿素a平衡浓度随着换水周期的减小先升高后降低;并且当换水周期小于3天时,减少换水周期能显著降低叶绿素a平衡浓度和叶绿素a峰值。因此,为了控制藻类在整个增长周期内的水华风险,在夏季和春秋季节推荐分别使用较好水质和标准水质的中水进行补水,并将换水周期控制在3天以内;冬季水华风险较小,中水水质指标可适当放宽并延长换水周期。

Using eutrophication model based on WASP,Chlorophyll-a peak and equilibrium value of treated wastewater recycled to urban landscape water body in various seasons was simulated.Results indicated that under stable wastewater quality and exchange cycle,summer has the highest algal bloom risk,followed by spring and autumn then winter.In summer,spring and autumn season,Chlorophyll-a equilibrium first rises then declines with the reduction of water exchange cycle.When water exchange cycle is less than 3d,reducing water exchange cycle can effectively reduce Chlorophyll-a peak and equilibrium value.As a result,in order to control algal bloom risk within the entire algae growth cycle,treated wastewater with better water quality are recommended for summer,spring and autumn season,and water exchange cycle should be controlled within 3d.Algal bloom risk in winter is little,the limit for treated wastewater quality can be extended and water exchange cycle lengthened accordingly.