Showing papers by "Hamidi Abdul Aziz published in 2000"

Study on the anionic natural coagulant aid for heavy metals and turbidity removal in water at p H 7.5 and alum concentration 25 mglL-laboratory scale

Abstract: This aims to search for an alternati ve natural polymer, which could be used as coagulant aids in water and wastewater treatment. The use of this polymer may save the amount of Alum (aluminium sulphate) dosed in water and wastewater treatments. An initi al study conducted in laboratory to look at suitab ility of using sago (Metroxylon spp) starch as an alter· native of coagulant aid as compared to the commercially applied syntheti c polymer. Artificial pollutants consist of selected heavy metals, i.e., nickel (Ni), manganese (M n), zinc (Zn), iron (Fe), cadmium (Cd) and turbidity have been used to stimulate the general real water and wastewater. Initial concentration of metals is set at 5 mg/L. Turbidity value at 300 NTU which, corresponds to the presence of coll oids or suspended solids in water is also used in the experi ment. Experiment has been conducted at optimum alum and pH values, predetermined beforehand. Jar test is conducted and results are obtained in terms of the removal percentage of each constituent, before and after the experiment. It could be concluded fro m the experiments that, at Alum concentration of 25 mg/L, the presence of sago starch improves the removal of selected heavy metals, i.e., nickel, manganese, zinc, iron, and cadmium. The improvements are obvious for Zn and Fe. However, there is no significant effect of turbidity removal in the presence of sago starch. This shows that the sago behaves as negatively charge polymer, which enhances the coagulation process of heavy metals. The study indicates that the use of sago starch as natural polymer is potential in wastewater industries for removing heavy metals.