The effect of different concentration of composite coagulant on different arrangement of electrodes for hybrid composite coagulation and lector coagulation treatment of landfill leachate

The development and the population of the country cause the increment of solid waste generation. When the solid waste is increasing, leachate production also increases. The drawback is the potential of leachate to seep into the ground soil that able to contaminate the surrounding area. In this study, the combined treatment of electrocoagulation and conventional coagulation was used to treat landfill leachate. The leachate sample was collected from Simpang Renggam Landfill. The electrodes used in this experiment were Iron (Fe) and Aluminium (Al) electrodes. The electrode was dipped into the beaker with a leachate sample (1000mL) and connected to the direct current power supply. The dimension of the electrode used was 200 mm x 50 mm x 1 mm. The main objective of this study was to determine the optimum ratio of composite coagulant used with the best electrode arrangement to treat the stabilised leachate under the influence of pH, current density, dose of coagulant, and duration of current flow. Three ratios of the composite were used PACTSa, PACTSb, and PACTSc. PACTSb. was the optimum ratio of composite coagulant with the arrangement of AlAl electrodes. The optimum conditions took place at pH 6, current density of 50 A/m , 0.3 g/L, and at 22 minutes of treatment time. The concentration of PAC and TS in PACTSb was 80 g/L and 30 g/L, respectively. The obtained removal at these optimum conditions for turbidity, colour, SS, COD, and ammonia nitrogen was 90%, 97%, 100%, 60%, and 15%, respectively. The sludge of the optimum condition was evaluated by sludge volume index (SVI), sludge settling rate (SSR), scanning electron microscopy (SEM) and particle size analyser (PSA). Based on the SVI result, the sludge settled very slowly and compacted poorly. The value of SVI for each electrode around 245 mL/g – 373 mL/g. The sludge settling rate shows that Fe ion settle faster compared to Al ion due to Fe ion is heavier. Through the SEM image, the surface of sludge from combined treatment was more compact compared to other methods. Besides, based on the sludge size, it showed the sludge was fine, compacted, and smooth, which indicated a good removal. Therefore, the combined treatment was effective to treat the stabilised leachate

Leachate treatment by conventional coagulation, electrocoagulation and two-stage coagulation (conventional coagulation and electrocoagulation)

Leachate is widely explored and investigated due to highly polluted and difficult to treat. Leachate treatment commonly involves advanced, complicated and high cost activities. Conventional coagulation is widely used in the treatment of wastewater but the sludge production becomes the biggest constraint in this treatment. Electrocoagulation is an alternative to conventional method because it has the same application but produce less sludge and requires simple equipment. Thus, combination of conventional coagulation and electrocoagulation can improve the efficiency of coagulation process in leachate treatment. This article is focusing on the efficiency of single and combined treatment as well as the improvement made by combined treatment. Based on review, the percentage reduction of current density and dose of coagulant was perceptible. As much 50% reduction of current density, duration of treatment, and dose of coagulant able to be obtained by using combined treatment. This combined treatment is able to reduce the cost and at the same time reduce the duration of treatment. Hence, the combined treatment offers an alternative technique for landfill leachate treatment on the removal of pollutants

Addition of composite coagulant (polyaluminium chloride and tapioca flour) into electrocoagulation (aluminium and ferum electrodes) for treatment of stabilized leachate

Physical-chemical method such as electrocoagulation (EC) and coagulation-flocculation processes work well for the treatment of stabilized leachate. This study investigated the efficiency of combined treatment (electrocoagulation and conventional coagulation) in removing colour and ammonia nitrogen (NH3-N) from stabilized leachate. For this combined treatment, the Fe and Al electrodes with the addition of composite coagulant (PAC and TF) were used. The considered factors were pH, current density, and duration of current flow. It was observed that, the highest removal of colour and NH3N were 96% and 13% at applied current density of 100 A/m2 that equal to 0.5 A and 20 minutes respectively. For single EC treatment, the highest removal was 88% for colour and 25% for NH3N at 60 minutes by 150 A/m2 that equal to 1.3A. Thus, it showed that the combined treatment performed better than single treatment in removing colour while reducing the current, and shorten the duration of current flow

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

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

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

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