| 摘要: | Low-molecular-weight organics, i.e., phloroglucinol P, resorcinol R, and p-hydroxybenzoic acid PHBA, were selected as
the target compounds to evaluate their removal and precursor reduction efficiency by coagulation under the presence of high-molecularweight
compounds. The results of this investigation reveal that turbidity removal efficiencies can achieve 95% and above, but the total
organic carbon removal for P, R, and PHBA are not remarkable, which are less than 20%. The chlorine demand after 168 hour is:
PPHBARhumic acids HAtannic acid TA; while the order of trihalomethanes THM formation is RPPHBAHA
TA, which is strictly dependent upon the nature of the model compounds. By applying the developed dissolved organic carbon DOC
removal model, both the maximum adsorption capacity and the residual DOC can be well predicted after coagulation. In this developed
model, the adsorption capacity a is a function of the sorbable part of organic compounds fsorbable, which can be expressed as:
a=e2.67fsorbable, both shown in nature and synthetic water samples. The fnonsorb increased as the molecular weight MW of the target
compounds decreased, suggesting that low-MW target compounds could not be easily adsorbed on the flocs. |
