Abdul Mutalib Leman

Effects of Storage Duration on Biodiesel Properties Derived from Waste Cooking Oil

The reduction of world oil reserves fossil fuels and increasing environmental concerns significantly influences the popularity of biodiesel as an alternative diesel. This research investigates the effects of storage duration of variant blending waste cooking oil ratio under different storage temperature on fuel properties. The biodiesel samples were stored at different temperatures and were monitored at regular interval over a period of 70 days. Blending of biodiesel was varied from 5vol % (WCO5) ~15vol% (WCO15) and storage temperature from 24°C~35°C. These samples were monitored on a weekly and the effects of storage conditions on properties of biodiesel such as density, kinematics viscosity, acid value, water content and flash point of biodiesel were discussed in detail. The observation of biodiesel shows that the increasing of storage duration of biodiesel derived from waste cocking oil influences to the increasing of density, kinematics viscosity, acid value and water content.

Testing on Building Material Using Waste Material in Fired Clay Brick

Clay brick is one of the building materials that have been used in the construction field for thousand years. It has been used as a major construction material because it can tolerate with severe weathering action, flexible properties and it is easy to handle. Many researchers have been incorporated waste material such as organic waste, waste treatment sludge, fly ash, cigarette butts, rice husk and processed waste tea into fired clay brick. This application gives an idea to use waste material that will give a minimum impact to the real environment. In this study, high calorific value waste such as cigarette butts (CBs) were incorporated into fired clay brick. Different percentages of CBs (0%, 2.5% and 5.0%) were added into the raw clay brick. All samples were fired up to 1050°C with different heating rates (1°C/min, 3°C/min and 5°C/min). Properties including compressive strength, dry density, firing shrinkage and water absorption are reported and discussed. The results show that the compressive strength of fired clay brick was obtained with 2.5% CBs of fired clay brick at 1°C/min heating rate compared to others. As for the density, it was reduced with higher percentages of CBs incorporated into the raw clays. From the results, water absorption was slightly increased when CBs were incorporated into clay brick. The results suggested that heating rates at 1oC/min is adequate to achieve optimum properties.

Effects of Intake Temperature and Equivalence Ratio on HCCI Ignition Timing and Emissions of a 2-Stroke Engine

Homogeneous charge compression ignition (HCCI) combustion, when applied to a gasoline engine, offers the potential for a noticeable improvement in fuel economy and dramatic reductions in NOx emissions. In this study, Computational Fluid Dynamic (CFD) is used coupled with detailed chemical mechanism (38 species and 69 reactions) for simulation of HCCI combustion of iso-octane and transitional flow inside the combustion chamber of a 2-stroke engine. Results show that increasing the overall gas temperature significantly advances the HCCI combustion timing. Concerning the equivalence ratio, by increasing it the ignition timing has been advanced and the maximum cylinder pressure has been increased. When equivalence ratio increases to more than 0.5 , NOx emissions significantly increases and go beyond 1000 [ppm].

The Comparison of Preheat Fuel Characteristics of Biodiesel and Straight Vegetable Oil

Biodiesel is an alternative fuel derived from varies sources of vegetable oils, animal fat, or waste frying oil to give the corresponding fatty acid methyl ester. The properties of alternative fuel of CPO biodiesel and SVO biodiesel have been investigated at different temperature. The biodiesel was blended up palm oil blending ratio from 515vol% (B5B15) and straight vegetable oil ratio from 515vol% (S5S15). The properties were tested at 27.5°C, 40°C, 50°C and 60°C with observed the changes of the density, kinematic viscosity, flash point, water contents, and acid value. In this study, properties of CPO biodiesel were found to have a higher value and diesel fuel under all ambient temperature. Under all ambient temperature, preheating CPO fuel increased value of density, kinematic viscosity, water contents, and acid value than SVO biodiesel.

The Evaluation of Indoor Microbial Air Quality in Two New Commissioning Higher Educational Buildings in Johor, Malaysia

The proliferation of indoor airborne microorganism in public institutional buildings such as schools and universities is often regarded as a potential health hazards to the buildings’ users. This issue is not new in Malaysia, a country with humid climate which favours the growth of microorganism. However, there is lack of research’s data, especially in higher institutional buildings in this country. The assessment of the indoor air quality is conducted in a university’s two new commissioning buildings located at Southern Peninsular of Malaysia. Both buildings utilized centralized air conditioning system. Concentrations of airborne microorganism were determined using a single-stage impacter (biosampler) as per requirement of National Institute of Occupational Safety and Health (NIOSH) Manual Analytical Method 0800. The acquired readings were compared to the standard level determined in Industry Code of Practice on Indoor Air Quality (ICOP IAQ) 2010. Other parameters such as relative humidity, temperature, and air velocity were recorded along the assessment. The mean concentrations of the total bacteria at the affected area of the two buildings are 1102.5 CFU/m3 and 813 CFU/m3 respectively and it is significantly higher compared to the maximum exposure limit of 500 CFU/m3. While, the mean concentration of total fungi at the affected area for two buildings are 805.7 CFU/m3 and 509 CFU/m3 respectively which are both higher than the reading of outdoors and unaffected indoor area although slightly lower than the maximum exposure limit of 1000 CFU/m3. This study provides a glance of the poor indoor microbiological air quality in new higher institutional buildings in this humid region.

The biocidal effect of potassium sorbate for indoor airborne fungi remediation

AbstractIndoor air contamination by fungi is common nowadays. It creates health problems, especially in people with asthma. Approximately 80% of these patients are allergic to fungus. In this study, a bioactive compound, potassium sorbate which is actively used in the food industry for antifungal purposes was evaluated for its ability to treat indoor airborne fungal contamination in two higher educational buildings at a university in Johor, Malaysia. Indoor air samplings of fungi were carried out at three different sites in each building using malt extract agar (MEA), which were incorporated with the mentioned biocide as culture media. It was shown under indoor and outdoor conditions that fungi were able to colonize untreated MEA. The effectiveness of the biocide to prevent the growth of fungi on treated MEA was compared with that of untreated MEA. It was clearly shown that the biocide can effectively prevent the airborne fungal growth at all six sites as the number of colony forming units was drastically...

In Vitro Inhibitory Assay of an Isolated Indoor Airborne Fungus from an Institutional Building of Computer Education by Using Potassium Sorbate

Currently, one of the main aspects of health and safety concern to facility owners and supervisors is indoor air quality. Meanwhile, pollution by airborne fungi in these facilities are acquiring more and more consideration due to its possible harmful side effects such as threats to occupiers’ health and damage to building parts and furniture. One of the recommendations to solve these indoor fungi pollution is bioactive compound which can act as a biocide. However, assessment of this compound in the real environment is often time-consuming and impractical. In this study, a bioactive compound, potassium sorbate which is commonly applied in food manufacturing was assessed for its efficiency as a biocide to restrict the growth of an isolated airborne fungus using an in vitro inhibition assay. The fungus was isolated from a new building of tertiary education of computer studies. It was grown on both biocide-incorporated MEA and untreated MEA. The diameter of the fungal colonies was noted time to time. The diameter of the colony of the treated fungus was downsized by 41.25% averagely in comparison with the untreated fungus. It was shown that potassium sorbate can restrict the growth rate of the isolated airborne fungus.

The development of an industrial air pollution monitoring system for safety and health enhancement and a sustainable work environment using QFD approach

Purpose – This paper aims to develop of an industrial air pollution monitoring system (IAPMOS) as one of the target solutions for monitoring mechanisms in the workplace.Design/methodology/approach – Quality function deployment approaches were used in this study. The process of getting data from workers was by using questionnaires. The questionnaire regarding the welding process work environment was given to two selected automotive industries located in Shah Alam, Selangor, Malaysia.Findings – From the data, the system development was analysed in order to formalize the specific needs of workers and management. The preliminary data were discussed regarding the development process and reliability factors that influenced the IAPMOS. The voice of the customer was then input during the design stage of IAPMOS.Research limitations/implications – The monitoring of industrial air pollution which was done in the welding process used a direct reading method and the date was assigned as “base line” during system devel...

Coating Bio-Resistance Test of Different Wall Finishing for Isolated Indoor Fungal Treatment by Using Potassium Sorbate Biocide on Wood

Malaysia is located on the equator has resulted in having two seasons wet and dry. Both of the seasons can influence indoor air quality of buildings promoting the growth of fungal. Fungal growth can occur with the combinations of temperature, relative humidity, substrate and others. Indoor and outdoor air quality is essential for building occupants to prevent the infection diseases caused by fungal. The goal of this study is to remediate the growth indoor fungal after treated with biocides on different types of wall finishing and evaluate the efficiencies of biocides to treat indoor fungal. In this study, the biocides are utilized as a coating for coating bio-resistance. The measurements of the fungal growth are made by growing the samples on realistic wood substrates on the different wall finishing such as paints and wallpapers. The mold that grew are affecting most of the rooms is selected. The air sampler that have been used to isolate the samples of indoor fungal according to NIOSH Manual Analytical Method (NMAM 0800), a guideline provided by National Institute of Occupational Safety and Health (NIOSH). The fungal growth was evaluated using the ASTM D5590-00 standard measuring on the surface of substrate. The results show that potassium sorbate as biocide was able to reduce the indoor fungal growth depending on the type of material used in the building.

Indoor Fungal Treatment by Using Potassium Sorbate as Bio-Resistance Coating for Different Plasterboard Wall Finishings

Good indoor environmental quality (IEQ) is desired for a healthy indoor environment. The microbial growth in indoor environments contribute into poor indoor environmental quality can cause various of health problems. Antimicrobial coatings are designed to generate a surface that is easy to clean and can also incorporate active agents, commonly called biocides, which prevent microbial colonization, the subsequent growth and bio-deterioration of the substrate. The aim for this study is to treat indoor environmental quality in buildings by reviewing the possible application of potassium sorbate used in food industry preservatives to be use as indoor antimicrobial. Plasterboard wall was used as a substrate to see the influence of different common wall finishing used such as paints and wallpapers on fungal growth. Potassium sorbate was tested against fungal isolated from affected room M146, FKAAS building. The total fungal counts in affected room was 806 cfu/m3. The ASTM D5590-00 standard was used to evalute fungal growth and potassium sorbate was effective to inhibit the amount of fungal growth on four common types of wall finishing used on plasterboard wall. As a result, the percentage reduction in growth between control and treatment sample were 10% on thin wallpaper, 15% on acrylic paint, 25% on glycerol-based paint and 60% on thick wallpaper.