AWWA MTC64602

Coagulation prior to membrane filtration is becoming desirable because it allows poorerquality source waters to be used and improves membrane permeability. However, relativelylittle information is available on the effect of coagulants on the performance of membranesystems. Thus, the objective of this research was to develop a technique for an automaticcontrol of coagulation pretreatment to enhance membrane performance in a coagulation-membranehybrid system.The work was done at pilot scale using a 400 m ³/day plant with submerged microfilters(CMF-S, USFilter, USA) in a water treatment plant. Raw water collected from the Han River wasused as feed water and polyaluminum chloride was used as coagulants. A computer-basedcontrol and data acquisition system was designed, installed and tested on the pilot plant. Anew form of fouling index (KFI), which implies the relative amount of particulate foulant andspecific cake resistance, was suggested and integrated into the automatic control system tokeep the coagulation conditions favorable for membrane filtration.The results indicated that the fouling potential of coagulated feed water could be described astwo parameters such as turbidity and KFI, which can be estimated using on-line instrumentsand sensors. Using turbidity and KFI as control parameters, the conditions for coagulationpretreatment were automatically determined. A comparison of membrane performancesindicates that the automatic control was more efficient to minimize coagulation dose (30 %reduction in coagulant use) and fouling (TMP < 50 kPa) compared to manual operation. Includes 12 references, table, figures.

Product Details

Edition:

Vol. - No.

Published:

03/01/2007

Number of Pages:

9

File Size:

1 file , 900 KB