Dosage and pH optimization on stabilized landfill leachate via coagulation-flocculation process

Abstract

Treatment on the generated landfill leachate is crucial as it can cause serious toxicological effects and environmental hazards, particularly when the unfavorable contaminants are left accumulated for a long period of time. The purpose of this study was to determine the optimum coagulant dosage of polyaluminium chloride (PAC) in selected dosage ranges (2250-4500 mg/L) and to analyse the ideal pH of leachate sample (pH 3-10). PAC was tested on stabilized leachate taken from Simpang Renggam Landfill Site (SRLS), by investigating the percentage removals of five significant parameters, which were suspended solids, chemical oxygen demand (COD), ammonia, and heavy metals (iron (Fe) and chromium (Cr)). The removal efficiency was determined by a series of experiments using jar test. From the obtained results, it was found that 3750 mg/L and pH 7 were the optimum conditions for PAC dosage and sample pH, respectively. The conventional optimization test showed satisfactory results for suspended solids, COD, Fe, and Cr at 95%, 53%, 97%, and 79% respectively, but had low removal on ammonia at 18%. It can be concluded that the coagulation-flocculation process has the potential to be applied as a primary treatment for stabilized landfill leachate in Malaysia.

Treat-ability of Manihot esculenta Peel Extract as Coagulant Aid for Stabilised Leachate

“…Polyaluminium chloride (R&M brand) was purchased from the local laboratory supplier that cost $15 per bottle. The preparation of PAC's stock solution was done by following the methodology of Mohd-Salleh et al (2018) and Ni et al (2015) that used 10% of PAC.…”

“…The selected range of dosages in leachate treatment by using a single PAC coagulant was from 2,250 mg/L to 4,500 mg/L (Mohd-Salleh et al, 2018). This dosage range was decided based on the preliminary study of dosage optimisation by using macro and micro ranges of coagulant dosages.…”

“…After the best dosage was obtained, the pH optimisation was taken place by adjusting the pH from 3.0 to 10.0. In the first dosage optimisation of PAC and MEP in this study, the amount of single optimum PAC at 3,750 mg/L was used as a constant dosage following the study of Mohd-Salleh et al (2018). Consequently, the different MEP dosages started from 50 mg/L to 500 mg/L was used as the coagulant aid.…”

Colour and Ammonia Nitrogen Removal from Stabilised Leachate Using Two Stages Coagulation: Tapioca coagulant and Electrocoagulation

“…Leachate is the liquid that drains or 'leaches' from a landfill [1]. Leachate may produce in various compositions based on the age of landfill and the type of waste contains [1][2]. Leachate from landfill usually contains extracted, dissolved, and suspended materials, some of which may be harmful [2][3].…”

“…Leachate may produce in various compositions based on the age of landfill and the type of waste contains [1][2]. Leachate from landfill usually contains extracted, dissolved, and suspended materials, some of which may be harmful [2][3]. The ineffectiveness of leachate management can lead to water pollution to the nearby river or groundwater.…”