Now showing 1 - 4 of 4
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Effect of organic matter on pathogen population during composting of municipal sludge

2020-12-29 , Hamzah N. , Hashim N.F. , Zainuddin N.S. , Kassim J. , Halip A.A. , Nur Liza Rahim

Population growth in Malaysia is expected to increase rapidly. Every sector of industry is expected to have a revolution including in agriculture sector. The utilization of organic fertilizer in agriculture as a green movement is to replace the chemical fertilizer subsequently, reduce the municipal sludge waste. Hence enhancing the growth and supply of nutrient to plant. However, the pathogenic growth in the final product is the greatest concerns. Thus, this study aims to evaluate the pathogen population in the compost of municipal sludge mixed with landscape waste for 90 days. The pathogen dynamic and its correlation with organic matter in 3 different ratios were analysed and recorded. The result showed that the pathogenic trends was uniformly increased at the early stage of composting and decreased gradually after reached the peak. R4 which comprises of equal ratio between municipal sludge and seed compost showed positive correlation with organic matter. R3 and R4 showed better removal of pathogen at maturity stage. Pseudomonas aeruginosa and Salmonella were failed to comply with the standard for R3 and only Salmonella failed for R4. This study supports the achievement of the Sustainability Development Goal (SDG) as an alternative way to combat the environmental issue by leveraging the usage of the waste produced for the purpose of the waste reduction and sustain the environment.

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Improving Iron and Copper Uptake by Changing the Ratios in Root of Vetiver Grass

2023 , Nursyafiqah Syuhada Abdul Halim , Nurhidayah Hamzah , Fauzi Baharudin , Nur Syahiza Zainuddin , Nur Liza Rahim , Nor Amani Filzah Mohd Kamil , Nor Azliza Akbar , Nur Shaylinda Mohd Zin

Phytoremediation using Vetiver grass (VG) has been used in the past few decades all over the world, but the effectiveness of its uptake mechanism in water has less been discussed especially in mixed metal conditions. Hence, the focus of this research was to determine and evaluate the heavy metal removal effectiveness of two heavy metals, copper (Cu) and iron (Fe), based on vetiver grass uptake and toxicity. Three treatments of Fe and Cu mixture were chosen, and individual concentrations act as a control. The vetiver grass at a height of 10 cm and a root length of 25 cm for each treatment was used and harvested on days 0,1, 3, 6 and 7. The roots were randomly cut, oven-dried and used the digestion method to extract the Fe and Cu in the root. From the result, vetiver grass has better Fe and Cu uptake ability in the mixture treatment compared to the individual treatment. Fe uptake is increasing up to 25.3 % in the presence of Cu (mixture 1). Meanwhile, for Cu, mixture 3 is an ideal ratio to increase the Cu uptake by 14.5%. It shows that both Fe and Cu facilitated each other's uptake in real wastewater conditions. There were also observed minimal toxicity signs such as necrosis throughout the experiment. The appearance of vetiver grass has changed in this experiment starting day 3 and remains yellowish. In conclusion, wastewater that contains a high concentration of Fe than Cu can promise the improvement of both Fe and Cu uptake by vetiver grass. This study benefits researchers that apply phytoremediation to remove heavy metals in wastewater by providing a guideline for Fe and Cu removal by vetiver grass. In future, the study will focus on the mechanism and interaction of Fe and Cu uptake by root

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Effect of bottom ash and limestone on the optimum binder content in Hot Mix Asphalt (HMA)

2022-01-01 , Nur Liza Rahim , Syakirah Afiza Mohammed , Noor Aina Misnon , Nurhidayah Hamzah , Roshazita Che Amat , Norlia Mohamad Ibrahim , Christina Remmy Entalai , Deák György

One of the most effective and simplest methods to minimize waste as well as reduce the environmental problems associated with waste disposal is by utilizing waste materials as a cement replacement in hot mix asphalt (HMA) mixtures which can provide the same or better stability as the conventional method. Fillers play an important role in the stability and strength of the pavement by filling voids between the aggregate particles in the performance of the HMA mixture. This research investigated the effect of the utilization of different types of filler (bottom ash and limestone) on the optimum binder content of HMA. Flow, stability, stiffness, air void in mix (VIM) and void filled with bitumen (VFB) were determined using the Marshal Method test in order to determine the optimum binder content of HMA for all mineral filler. The results of the Marshall test for each filler have been compared with the JKR standard specification. The optimum binder content for bottom ash, limestone and Ordinary Portland Cement (OPC) was 5.42%, 5.65% and 5.54%, respectively. All values of mineral filler used meet the JKR standard specification, where the range is between 4 and 6%. From the result achieved, the bottom ash has the lower optimum binder content value compared to the limestone and OPC. When the lower binder content is used in the bituminous mixture, the cost for pavement construction will be reduced.

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Sustainable utilisation of quarry dust waste in concrete: Strength performance

2020-12-29 , Nur Liza Rahim , Abd Rahim, Noor Aini Syafiqah , Norlia Mohamad Ibrahim , Roshazita Che Amat , Hamzah N. , Misnon N.A.

Each year, a large amount of quarry dust (QD) waste is disposed into landfills. This waste material was obtained as a by-product during the production of aggregates through the crushing process of rocks at the quarry site. The increasing value of waste will have a significant impact on health and the environment. Reusing such wastes by including them into building materials is a practical answer for the pollution problem. Therefore, this research was to observe the possibility of quarry dust to be included in a concrete mix. The quarry dust has been used as a partial replacement for cement proportion at different levels of replacement (25%, 30% and 35%). Quarry dust was used as the main material in this project to measure the effectiveness of concrete performance. In this research, the quarry dust composition was determined by using X-Ray Fluorescence Spectrometer (XRF). From the x-ray fluorescent spectrometry test result, the quarry dust displays some similar characteristics with the Ordinary Portland Cement (OPC) where it comprises a high composition of Calcium Oxide (CaO). Research were done to determine the optimum percentage of quarry dust in concrete. The result shows that 25% of quarry dust and 75% of cement is the best percentage that can be used in concrete mixture to reach the standard strength. From an economic point of view, the proposed optimum concrete mix was found to be the most economical with the reducing of RM 33 per 1 m3 of the concrete mixture. The results indicated that the quarry dust waste could be utilised as cement replacement to produce durable and resilient concrete. These materials could be an alternative low-cost material for concrete and at the same time provide a new disposal method for the waste.