Nature Environment and Pollution Technology

Abdul Fattah Abu Bakar ¹, Azhar Abdul Halim ¹, Marlia Mohd Hanafiah ¹

Affiliations
1 School of Environmental and Natural Resource Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, MY

Abstract

This study was conducted to assess the optimization of the coagulation-flocculation process and to investigate the interactive effects of experimental factors in automotive wastewater treatment. Based on the coagulation-flocculation process, an automotive wastewater was treated using polyaluminium chloride as the coagulant and anionic polyacrylamide as the flocculant. Response surface methodology was applied to optimize the operating variables: coagulant dosage, flocculant dosage and pH. We found that the optimum conditions for chemical oxygen demand removal (73.7%) were, a coagulant dosage of 73.3 mg/L, a flocculant dosage of 3.46 mg/L and pH 7.45. The optimum conditions for the removal of heavy metals (Fe, Cr, Cu) were, a coagulant dosage range of 65.26-170.9 mg/L, a flocculant dosage of 5.36 mg/L, and pH 6.13 (with 78.7-99.7% of heavy metals removal). The experimental data and predicted model proved that RSM is a suitable approach for optimizing the coagulation-flocculation process in automotive wastewater treatment.

Keywords

Coagulation-Flocculation, Automotive Wastewater, Polyaluminium Chloride, Anionic Polyacrylamide, Response Surface, Methodology.

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Azhar Abdul Halim ¹, Kee Ke Han ¹, Marlia Mohd Hanafiah ¹

Affiliations
1 School of Environmental and Natural Resource Sciences, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, MY

Abstract

Removal of methylene blue (MB) from aqueous solutions by river sand using batch and column techniques was investigated. It was observed that the maximum removal of MB was achieved at pH 4, 45 minutes contact time and 500 g/L dosage adsorbent river sand. Adsorption data were better fitted to the Langmuir isotherm. Pseudo second-order kinetics was most suitable to explain the kinetic study. The removal of methylene blue by column adsorption of river sand was ranged between 29.01% and 99.99%. It was found that the adsorption of methylene blue by river sand was more conformed to the model Thomas. In different flow rates study, flow rate of 10 mL/min in the column adsorption can better remove the methylene blue. This study shows that the river sand cannot undergo desorption.

Keywords

Methylene Blue, Dye Wastewater, Adsorption, River Sand.

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Anuar Ithnin ¹, Muhammad Shakirin ¹, Nurhudayanti Mohd Yusuf ¹, Shamrul Aizam Abd Rahman ¹, Azhar Abdul Halim ²

Affiliations
1 Environmental Health and Industrial Safety Program, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, 50300, Kuala Lumpur, MY
2 School of Environment & Natural Resource Sciences, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor, MY

Abstract

The former landfill site produces various combinations of gases that can cause health problems. The objective of this study was to determine the influence of air quality on the residents' respiratory health that occupy buildings at the former landfill site at Taman Sri Manja, Petaling Jaya, Selangor compared with the control which in PPR Air Panas located at Setapak, Kuala Lumpur. Methods that are used for this study are gas sampling using aeroqual and multi-log gas detector. High-volume sampler (HVS) was used for PM₁₀ determination. The open plate method was used to determine total count formed by microorganisms. Questionnaire forms and peak flow meter were used to determine the value of Peak Expiratory Flow Rate (PEFR) of 196 respondents in the case study and 190 respondents in control. Results showed that all the parameters including gases, PM10, heavy metals and total count of microbes under the estimated standard value have no significant difference between the case study and control. There is significant difference (p=0.031) of PEFR (L/min) value between respondent at case (347.54 ± 89.50) and control (326.97 ± 97.90). Respiratory symptoms score also showed significant differences (p=0.04) between respondents at case (1.38 ± 0.36) and control (1.30 ± 0.37) location. Although there was significant difference (p<0.05) between the average value of peak flow meter and the expected value, but the value for both case and control study are between the range of 20% under the expected value which indicated normal respiratory health status. As conclusion, there was a significant difference of PEFR average value in case and control study. The presence of pollutants contributed to the high respiratory symptom score at the case location compared to control.

Keywords

Air Quality, Landfill Site, Respiratory Human Health, Landfill Gases, Heavy Metals.

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