L.A.'s NEW CLARIFIER INLET NEARLY DOUBLES HYDRAULIC CAPACITY

摘要

The City of Los Angeles' Hyperion Treatment Plant was recently upgraded to fullrnsecondary treatment for a design, dry weather flow of 450 million gallons per dayrn(mgd). Nine pure oxygen reactor modules were constructed, each of 50 mgdrncapacity. Each module includes four 150-ft (45.7 m) diameter circular clarifiers. Afterrncommissioning of the first four modules in 1996, a testing program revealed problemsrnof floc washout at hydraulic loadings only slightly above dry weather flow conditions.rnA Clarifier Optimization Program was developed which field tested a variety ofrnproposed improvements. A new energy dissipating inlet, termed the LA-EDI,rnproduced dramatic improvements in hydraulic capacity. Sustained loadings of 1558rngpd/ft~2 (2.65 m/h) and a peak loading of 1700 gpd/ft~2 (2.89 m/h) for 3-hours werernachieved. LA-EDIs were then retrofitted into all 36 circular clarifiers at Hyperion,rnhelping to resolve a significant peak hydraulic problem.