Now showing 1 - 10 of 14
  • Publication
    Alum Sludge from Water Treatment Plant Potentials to Remove Aqueous Lead and Phosphorus
    ( 2023-06-09) ;
    Kamal N.K.
    ;
    Azani N.N.M.
    The use of alum as a coagulant throughout the process of drinking water treatment produces alum sludge as a by-product. The quantity of the sludge is enormous, so it is essential to manage and dispose appropriately. Conventionally, the authority of water treatment plant deposited the sludge in waste disposal area (landfill). To reduce the solid waste, many studies and research was done to utilize the use of this alum sludge. The reuse of this aluminium sludge as a solid adsorbent is one of the proposed applications, but alteration and characterization are required for this study. A batch process was developed to evaluate the potential of alum sludge for lead and phosphorus removal. The alum sludge undergoes chemical pre-treatment to enhance the adsorption capacity of the adsorbent (alum sludge). The dosages of alum sludge, concentration of heavy metal and pH were affecting the removal capacity was studied. The percentage of removal were nearly 100 % of both heavy metals Results demonstrated that alum sludge from water treatment plant is potential as adsorbent for removal of heavy metal.
  • Publication
    Compost bed size influences the co-composting of cow dung and spent mushroom at mesophilic stage
    ( 2021-05-24) ;
    Firdaus Shaheen A.A.
    ;
    Zainol N.A.
    Composting is an approach to convert typically organic waste into soil amendment for nutrient enhancement and plant growth. The composting of cow dung and spent mushroom for 13 days to study the potential of degradation of organic matter at different size of laboratory scale. The compost bed size is crucial to study because larger amount of raw materials will reduce the O2 concentration inside the compost bed. In this study, the aerobic compost bed size of 2, 4 and 6 kg were prepared at 60 % of initial moisture content, 20 mm particle size and 28:1 of initial C/N ratio. Temperature, moisture content, porosity, pH, C/N ratio and total organic carbon were analysed to evaluate the degradation process. All compost beds recorded the mesophilic phase (>30 ℃) upon composting of initial total organic carbon of 35 to 37 %. Moisture content reduced to lower than 43.9 %, total organic carbon reduced to less than 25 % and compost beds were nearly neutral (pH 7) at the end of composting. The findings show that, all the compost beds follow the first-order kinetic reaction as R2 larger than 0.880. The degradation rate constant of 2 kg compost bed showed the largest value, 0.0503 day-1 indicates the best composting process and results the smaller compost bed is preferable for mesophilic phase composting.
  • Publication
    A study of liquid-liquid extraction system performance to remove lead from aqueous solution
    Lead (Pb) is one of the top-heavy metal pollutants often encountered in industrial wastewater. The presence of high levels of Pb in the environment may cause long-term health risks to humans. This study was focused on the removal and stripping of lead solution using liquid-liquid extraction (LLE) process. LLE was conducted using three types of extractants with sulphuric acid, H2SO4 as a stripping agent. Experimental parameters studied were types of extractant bis(2-ethylhexyl) phosphate (D2EHPA), trioctylamine (TOA) and tributylphosphate (TBP) and concentration of extractant (0.005, 0.05 and 0.5 M) and types of diluents (kerosene and toluene) respectively. The result indicates that, D2EHPA shows a good performance for removal of Pb compared to TOA and TBP where the highest extraction rate of lead was 93.92 %. Meanwhile, TBP shows the highest stripping rate of lead which is 93.57 %. Kerosene was found to be the best diluent compared to toluene. Overall, the optimum Pb extraction and stripping was obtained at 0.5 M D2EHPA and 0.005 M TBP with 250 rpm stirring speed, 5 min stirring time, 0.5 M H2SO4 and treat ratio 1:1. This LLE process has a good potential to aid in low-cost and environmentally friendly.
  • Publication
    Aerobic Co-composting of Spent Mushroom Medium Using Food Waste Fermented Liquid
    ( 2024-01-01) ;
    Zaidnuddin A.S.
    ;
    Mokhtar N.F.
    ;
    Zulaika E.
    ;
    Shovitri M.
    ;
    Kuswytasari N.D.
    ;
    Hidayati D.
    ;
    Zabidi K.A.A.
    Spent mushroom medium and dried sludge from bioethanol industry can be utilized into beneficial organic compost after completion the composting process. Food waste fermented liquid and commercially effective microorganisms (EM) from EMRO Sdn. Bhd. were used as the microbial inoculant for the aerobic composting. Three kg of composting pile made of spent mushroom and dried sludge are used to obtain a 23.07 C/N ratio at the initial composting process. In order to ascertain the impact of composting process in seven days, the sample from each of the composting beds for analysis of temperature, pH, moisture, and total organic matter was assessed. Food waste fermented liquid and commercial EM composts reached the thermophilic phase (40 Â°C) after a day of the composting process. Moisture content showed a significant result for both composting piles on day 1 due to the highest evaporation of water at the thermophilic phase. The composting process was not extended until reached stability and maturity phases; thus, the pH for both composting piles was recorded at 9, which is far from the stable compost normally at neutral pH (~7). The organic matter content of each composting pile showed gradually decreased during the composting process. The degradation rate for the composting pile using food waste fermented liquid showed slightly higher than commercial EM which was 0.0363 and 0.0232 day 1, respectively. In conclusion, food waste fermented liquid shall be used as a replacement for EM commercial as a microbial inoculant for the composting process based on the results shown in this study.
  • Publication
    Compost Physical Properties Study on Degradation of Poultry Manure Composting in Closed-Aerated Composter
    A variety of parameters including physical, chemical, and biological properties of different input materials contribute to different composting performance. This study aimed to investigate the compost physical properties (bulk density, porosity, specific surface area and water holding capacity) on the composting process at different initial moisture content (MC). The degradation of total organic carbon (TOC) for the compost inoculated with Bacillus coagulans (BC) and effective microorganism (EM) was determined. The composting materials consisted of 50 % sawdust, 12 % chicken dung and 38 % rice husk with a fixed initial C/N ratio of 30. A closed-aerated composter was fabricated with an optimum air flow rate of 0.3 L/min.kg compost to avoid O2 limitation for 7 d of composting. The compost temperature was recorded to exhibit the active reaction between microorganisms and compost materials will generate a considerable amount of heat. The effect of the initial MC of the compost bed has been intensively investigated with regards to compaction analysis and compost particle for the composting inoculated with BC or EM in an aerated closed-system composter. The results showed that composting using the single strain of BC provides comparable results to that degraded by the commercial mixed culture EM.
      10  47
  • Publication
    Nitrogen Uptake Efficiency on Water Spinach in Controlled Planting Medium Using Spent Mushroom Medium Compost and NPK-16 Fertilizer
    ( 2023-01-01) ;
    Mokhtar N.F.
    ;
    Zaidnuddin A.S.
    Ipomoea aquatica (water spinach) is a long and leafy green vegetable with hollow stems that easily grown on the water surface or damp soil. It is a tropical and subtropical perennial herbaceous aquatic or semi-aquatic plant. Water spinach needs more water compared to other vegetable crops, thus suggested to employ slow-release fertilizer for sustain the available nutrients in the soil that being leached off by watering. Nitrogen uptake is the major issue in agriculture to sustain the quality of crops and soil for planting medium. Several studies have been conducted on many types of fertilizer and showed beneficial results on growth of water spinach. This study aimed the research on comparing the nitrogen uptake rate study during the planting period for both organic and inorganic fertilizer. The measurement of plant height, dosage of fertilizer and nitrogen uptake were highlighted in this research activities. Pots has been used and the growth of water spinach was evaluated along 30 days of planting. The spent mushroom medium (SMM) compost and NPK-16 fertilizer were used to evaluate the rate of nitrogen uptake for water spinach based on the Michaelis Menten kinetic study to evaluate the best fertilizer dosage with research design activities. It was showed that a 1 g of NPK16 fertilizer was equivalent to 2 g of SMM in the amount of N. There was a clear correlation between the nitrogen concentration and the water spinach growth. From the result obtained, the application of NPK16 fertilizer provided higher nitrogen value initially. However, SMM compost improved both physical and chemical to help water spinach absorbed sufficient moisture and nitrogen uptake at a steady state rate owing to the higher organic matter in SMM. As a conclusion, SMM compost resulted better nitrogen uptake efficiency by improved the soil fertility and better growth of water spinach.
      25  31
  • Publication
    Cactus opuntia as coagulant in treating landfill leachate via coagulation process
    ( 2021-02-23)
    Zainol N.A.
    ;
    Syarmimi F.N.
    ;
    ;
    Yusoff N.A.
    ;
    Ghani A.A.
    ;
    Coagulation-flocculation treatment is often used for the treatment of stabilized landfill leachate. However, uses a non-environmentally friendly chemical coagulant which is a threat to environment quality, therefore Cactus opuntia is proposed to replace the use of current chemical coagulants such as aluminium sulphate in order to achieve sustainable growth. In this regard, the comparative suitability of Cactus opuntia and alum as coagulants for the treatment of the stabilised leachate of the Padang Siding Landfill Site was evaluated via a series of Jar Test experimental works with a rapid mixing speed of 100 rpm for 3 minutes, a slow mixing speed of 30 rpm for 10 minutes and a set-up period of 30 minutes. In addition, the sludge volume index (SVI) of the treated leachate sample was calculated under optimised conditions. Cactus opuntia was able to remove 66.8 per cent turbidity and 42 per cent COD at optimal pH 2 with a favourable dose of 8000 mg / L, while the optimal pH 5 with a coagulant dose of 8000 mg / L induced 94.5 per cent turbidity and 69 per cent COD reduction from the same leachate sample. In addition, the SVI of alum coagulant was 42.2 while the Cactus opuntia was 4.45 with a relative ratio of alum to opuntia of 9:1. Cactus opuntia may also be proposed as a plentiful coagulant of metal cationic ions such as aluminium, iron and silica elements for the treatment of leachate.
      25  2
  • Publication
    Surface Water Treatment with Natural Starches as Coagulant via Coagulation Process
    In this study, natural polymers in the forms of starch from sago and tapioca were used as coagulant. The removal of turbidity and chemical oxygen demand (COD) using coagulation process from river water was examined. The treatment on the river water sample was evaluated via a series of Jar Test experimental works with rapid mixing speed of 120 rpm for 1 minute, slow mixing speed of 30 rpm for 20 minutes and settling time of 60 minutes. The tapioca starch removed 93.7% of turbidity at dosage of 1000 mg/L. While, sago starch successfully removed 96.4% of turbidity under optimum dosage of 2000 mg/L. pH 12 was optimum pH for turbidity removal by using sago and tapioca starch whereas the highest percentage of COD removal occurred at pH 4 using sago and tapioca starch. At pH 4, tapioca and sago starch removed 22.5% and 25% of COD respectively. Overall tapioca starch showed better removal percentage of turbidity compared to sago starch throughout the experiment study. Generally, the usage of natural polymers as coagulants is good for turbidity removal; however, it did not work well on COD removal.
      3  36
  • Publication
    Synthesis and characterization of carboxymethyl cellulose derived from office paper waste for methylene blue dye removal
    The aim of this research was to extract cellulose from office paper waste and converted into carboxymethyl cellulose (CMC) based flocculant to treat methylene blue (MB) dye solution. The yield of extracted cellulose obtained was 62.17%. Three different CMC samples were prepared. Degree of substitution (DS) for CMC-1 is 0.6585, CMC-2 is 0.8124 and CMC-3 is 0.8946. This proved that CMC are substituted into cellulose structure due to the DS of the commercial CMC are in the range of 0.4 to 1.5. The coagulation flocculation process of the MB dye shows that the CMC-3 was effective for methylene blue dye removal with highest percentage (98.14%) at pH 9.0, flocculant dosage of 210 ppm with 100 ppm MB concentration solution.
      2  39
  • Publication
    Utilization of Spent Mushroom Compost in Grey Oyster Mushroom Cultivation
    ( 2023-01-01)
    Zakaria Z.
    ;
    Seng T.T.C.
    ;
    ;
    Zabidi K.A.A.
    ;
    Salim S.K.
    Utilization of spent mushroom substrates (SMS) in mushroom cultivation is considered useful to overcome the short supply of wood sawdust and environmental pollution. Composted form of SMS is found to have improved in their carbon and nitrogen content that is needed in mushroom cultivation. This study is aimed to investigate the effect of supplementing spent mushroom compost (SMC) in the mushroom cultivation substrate. Five formulations for the mushroom substrates were prepared by mixing both the SMC and rubber sawdust in the ratios of 1:1, 1:2, 1:3, 2:1, and 3:1 by dry weight, respectively. The commercial sawdust substrate bags were used as a control. The comparisons were evaluated based on the growth rate of the mycelium and also the time is taken by the spawn to fully colonize the substrate bags. The results showed that the amount of SMC between 25 and 50% was suitable for the cultivation of grey oyster mushrooms. The average growth rate of mycelium from both the ratios of 1:2 and 1:3 at 0.8184 and 0.8281 cm day−1 respectively, did not show any significant difference (P > 0.05) over the control at 0.8246 cm day−1. This was followed by the ratio of 1:1 at 0.7375 cm day−1. The slowest growth rate was obtained from both the ratios of 2:1 and 3:1 with 0.5783 and 0.5414 cm day−1 respectively. The highest mushroom weight was obtained from rubber sawdust substrate (210.77 g) and closely followed by 25% (198.74 g) to 33.3% (188.44 g) SMC. This study proved that SMC can be used as an alternative substrate to replace the current rubber sawdust used in mushroom cultivation as it did not significantly affect the growth rate of the mycelium.
      24  2