Kinetic Studies on the Adsorption of Sungai Sireh Raw Water's Natural Organic Matters

The presence of dissolved organics in potable water supply is aesthetically undesirable. Apart from imparting colour, taste and odour to treated water, it is also potentially hazardous to health. Two types of coconut shell derived activated carbon, KI-6070 and KI8085, provided by Kekwa Indah Sdn Bhd, were studied for the removal of dissolved organic compounds from Sungai Sireh Water Treatment Plant raw water, notorious of its high organic content. The respective external surface area of the KI-6070 and KI-8085 are approximately 277 m/g and 547 m2jg. The rate constant (~) for the KI-8085 was higher than that of the KI-6070, ranging between 30 and 70 %, for adsorbent dosages between 1.0 and 3.0 g. This was expected since the total surface area (specific and external surface areas) of the KI-8085 was higher than that of the KI-6070. The rate constant for the mass transfer was a function of the adsorbent dosage where both adsorbents indicated a proportional increase in the rate constant with increasing adsorbent dosage. The increasing dosage raised the intra particle diffusion rate constant (K.,) for both the KI-6070 and KI-8085, with the KI-8085 having a higher intra particle diffusion rate

Cement-stabilized Modified High Fines Melaka Series for Roadbases

Roads are a crucial infrastructural element in the progress of a nation. Unavailability of suitable base materials causes total building cost to escalate. Strict adherence to standards to satisfy maximum working conditions would disregard the abundant supply of substandard materials. This paper discusses the potential exploitation of such substandard materials through modification of the strength characteristics. Rural and farm roads in developing countries are generally lightly trafficked, thus justifying a lower strength criterion (1.7 MN/m2 ) than normally adopted. Soils with high fines content are unsuitable for cement stabilization. The selected Melaka series was modified by the addition of river sand. Cement was subsequently added to the mixture and stabilized mechanically. Various soil sand-cement proportions were studied in terms of strength characteristics. A significant increase in strength, from 0.2 MN/mt to nearly 3 MN/m2, was noted with soil sand ratio of]:] with 12% cement content. This represents about a 14fold strength increase satisfying the current compressive strength of 2.8 MN/ mt for roadbases. The unit cost of producing the mixture was equivalent to supplying crusher run in a typical road project. The 1.7 MN/m2 criterion was met with a minimum cement content of 8% and a soil·sand ratio of 2:1. With 1.7 MN/m2 strength criterion, nearly 35% savings could be made by using the modified Melaka series soil instead of crusher run

Effects of Effective Size in Rapid Sand Filtration

A study on the effects of effective size of sand media in a rapid filtration process with respect to turbidity, filter run and flow rate was carried out at Sungai Langat Water Treatment Works. The findings of the study show no significant difference in the final tUrbidity achieved with effective sizes (cj range between 0.4 and 0.9 mm. However, filter run increases with higher effective sizes. Filter run is also affected by a change in flow rate a 50% increase in flow rate results in the 'reduction of filter run by two hOUrS for the effective sizes studied

Head Loss Characteristics in a Burnt Oil Palm Shell Granules Filter Compared to a Sand Filter and its Application in Rapid Filtration

Studies were carried out on the initial head loss and the operational head loss occurring in single medium filters of sand and burnt oil palm shell (BOPS) as well as in a dual-media filter consisting of these two materials. The experimental initial head loss values in filters were shown to agree with the values predicted by the well-known Fair and Hatch formula. The characteristics of the experimental operational head loss were quite similar to the Ives's prediction. The dual-media filter proved to be a cost effective technique for water filtration due to its long running time and high quality filtered water

Checking the adequacy of rainwater harvesting system for housing and landscaping

Rainwater harvesting has been the main source of water supply for potable and non-potable uses in the old days because the water conveyance systems were not used for water distribution and the method used for rainwater harvesting was simple and primary (rainwater was mostly collected from roofs and some was collected directly from the sky). Usage of the collected water volume from rainwater harvesting was direct and without any treatment. Presently, the water supply systems have improved but the demand is increasing due to the population growth, and development. Rainwater can be used for potable and non-potable uses. The potable uses include drinking, cooking, bathing and washing. Usually, the rainwater used for this purpose must be treated to remove the contaminants. Non-potable uses include flushing toilets, watering garden and washing floor where treatment of rainwater is not required for these purposes. The volume of rainwater collected from rainwater harvesting system varies from place to place and depends on weather. In the present study, a rainwater harvesting system was installed in the Faculty of Engineering, University Putra Malaysia, Malaysia. The system is composed of the catchment (roof), gutter, pipe, steel tank and treatment unit. From 20 different rain events, the collected volume of the rainwater from different events ranges between 0.17 m3 and 2 m3. The daily water consumption is monitored for one month and compared with the collected rainwater volume. The volume of collected rainwater is found to be adequate to meet the non-potable uses. In a tropical country like Malaysia it is easy to collect 2 m3 in a single rain while 10 m3 is collected annually in Zambia, Africa from a roof of almost of the same size. The rainwater harvesting can be used for landscaping and the computation made to determine the volumes of yield and consumption shows that rainwater is also adequate to meet the requirement for landscaping in rainy months

Empirical model simulating rainwater harvesting system in Tropical area

Rainwater harvesting is the technique of capturing the rainfall to meet some water needs in both urban and rural areas. The volume of rainwater collected from rainwater harvesting system varies from place to place and depends mainly on the climatic condition. Typically, the rainwater harvesting system is composed of the catchment (roof), gutter, rainwater pipe, and storage tank. Reliability of a rainwater harvesting system mainly depends on the collected volume in rainwater storage tank and it is also used to check whether the collected volume of rainwater can meet a specific water demand (either for potable or non-potable uses). In the present study, a rainwater harvesting system is installed at the Faculty of Engineering, University Putra Malaysia. The system is tested using data from 24 different rain events. The collected data includes rain depth and rainwater volume. It is found that the rainwater volume ranges form 0.027 m³ to 4.03 m³. The actual data is used to produce an empirical model for predicting the collected rainwater volume. Calibration and validation processes are conducted to the proposed model and T-test shows that the model prediction is within 95% level of confidence. Also, the water consumption for toilet flushing is monitored using water meter. Reliability of the installed rainwater harvesting system for toilet flushing is computed. It is found that the system reliability ranges from 26.61 % to 100 % depending on daily water demand and recorded rainwater depth

Utilising Malaysian Fibre in Stone Mastic Asphalt as a Replacement of Imported Fibre

Stone Mastic Asphalt (SMA) technology is currently used in many countries. This is a gap grade mix with a high percentage of coarse aggregates. As such there is a tendency for the binder in the gap-graded mix to drain down during the hot weather that may cause premature failure of the mix. Various fibre types have been used successfully in SMA. However, the overall cost of the mix tends to be much higher than that in conventional mix. This paper looks into the suitability of the Malaysian fibre for the use in SMA. The fibre is analysed and compared with traditional European fibre that is commonly used in SMA. Several experiments on the fibre have been done including Fibre Drain Down Test and Morphological analysis using the Scanning Electron Microscope (SEM). Besides this, chemical analysis was also carried out with a variation of cellulose content, particle size and Gas Chromatograph analysis. The result of the preliminary analysis shows that Malaysian fibre has the potential to replace the imported traditional fibre

Preliminary evaluation of a hydrophilic microfiltration membrane in treating high strength wastewater

In this study, two types of flat sheet membranes were produced and tested in the laboratory. These types of membranes are hydrophilic and hydrophobic flat sheet membranes. The membranes were prepared using a phase-inversion technique. Three synthetic based polymers were used to produce the membrane. These polymers are polysulfone (PSF), polyethylene glycol (PEG), and N-methyl- 2-pyrrolidone (NMP). Fourteen polymer solutions were formulated by Response Surface Method and the polymers concentrations used were 15 wt % for PSF, 30–40 wt % for PEG and 45–55 wt % for NMP. The produced membranes were physically characterized by scanning electron microscope (SEM) measurements of their top surface and cross-section images. The produced membranes are used to test the flux value for pure water, synthetic wastewater and raw wastewater using a bench scale unit. Meanwhile, the rejection performance is evaluated using synthetic wastewater and raw wastewater. The pure water flux for the hydrophobic membrane ranges from 78.45 L/m2h to 88.05 L/m2h, while pure water flux for the hydrophilic membrane ranges from 41.92 L/m2h to 52.25 L/m2h. Meanwhile, the COD rejection rate from raw wastewater was greater for the hydrophilic membrane (58%) compared to the hydrophobic membrane (42%). Results obtained from the bench scale unit show a gradual increase in the percentage removal of COD, BOB and TOC with time and it increased from 0 to 75% from the 1st day to the 8th day while only a 20% increment was observed from the 8th day up to the end of the test. But, the percentage removal obtained form hydrophilic membrane is slightly higher than the percentage removal of the hydrophobic membrane