Applied Mechanics and Materials Vols. 773-774

Abstract: Subsea processing equipment’s are deployed in Deepwater / subsea marginal field, fields having challenging reservoir characteristics (which includes: high viscosity, high GVF) in order to economically recover oil and gas. They includes: multiphase booster pump, subsea separation and compression equipment’s. These equipment’s faces a high level of uncertainty as regards well and reservoir conditions, putting the equipment in an unfavorable condition covering a wide and variable range of processes including transient Flow, variable oil flow, fluid pressures, temperature and gas compression effects. More so, knowledge engineers in different areas are assessing this domain in different ways making the performance parameters and relations to be defined differently when utilizing computer based tools for assessment and selection. A four step process is proposed which are: domain knowledge acquisition, failure data analysis, knowledge model and a knowledge base system will reveal the key components and parameters that are needed to make an optimum decision. The applicability of these four step process is demonstrated in the assessment and selection of subsea multiphase booster pumps.

Abstract: Abstract. Groundwater quality is generally affected by the soil type and being polluted naturally due to the soil properties itself. This paper aims to examine the effectiveness of reducing the contamination of groundwater by a simple treatment using duo soil aquifer treatment (SAT) and therapy-electrolysis processes. The SAT was applied using physical recharge well system (REWES) in deep clay medium. The filtration in the well was also properly designed to purify the abstraction and treat discharges. Other contaminations such as fluoride, nitrate, chloride and turbidity in the groundwater were treated by therapy-electrolysis techniques. This treatment method reduces more than 64% of contaminations contain without affecting its mineralogy. Therefore, these duo treatments have the best combination of methods to reduce the unneeded contaminations without affecting the groundwater purity. A groundwater eco-distribution system is useful to be implemented in terms of economic process and is ecological friendly for water distribution facilities.

Abstract: The kinetic of microbial growth and substrate utilization can be used to predict the fate and behavior of contaminants like PAHs in the environment through appropriate models. Further kinetic study results are useful in evaluating and weighing suitable treatment option for remediation and clean up of contaminated sites.. In this research a mathematical model for biodegradation of PAHs using isolated bacteria from municipal sludge was studied.. The model was developed using the Monod equation.. Results showed that the remaining PAHs in all samples decreased within time.

Abstract: Excessive nitrogen in domestic wastewater discharge accelerates eutrophication in an aquatic ecosystem. To treat wastewater high in nitrogen conventionally are more expensive, complex and generate high amount of sludge. In line with this situation, rock filters (RF) emerged as one of attractive natural wastewater treatment method to treat wastewater high in nutrient because this filter system is easier to maintain, using low-cost filter media, and environmentally-friendly technology. However, studies on the removal of nitrogen in the system are still limited due to nitrification study under warm climate. Thus, an aerated rock filter system has been designed in this study to remove ammonia nitrogen from domestic wastewater using the recommended hydraulic loading rate in warm climate condition. The laboratory aerated rock filter system has been in operated for 2 months with 5 weeks of sampling. The filter influent and effluent samples have been collected and analyzed twice a week for Total Kjeldhal Nitrogen (TKN), ammonia nitrogen (AN), nitrates ,pH, temperature, DO and alkalinity to monitor the filter performance in removing nitrogen. Results from the laboratory experiments show that AN in wastewater was oxidized to nitrate and efficiently removed as the removal of ammonia nitrogen was ranged from 66.05 % to 91.30 % and the removal percentage of TKN was ranged from 63.23 % to 87.68 %. The temperature was in the range of 25°C to 27.5°C, pH value was in the range of 6.34 to 8.04, DO was from 6.64 mg/L to 7.75 mg/L, and the alkalinity was from 15 to 110 as mg /L CaCO₃. Therefore, from this laboratory experiment it can be concluded that aerated rock filter system has high potential in removing AN and TKN. The system also able to produce a good final effluent quality which is comply with the effluent requirement for nutrient removal in wastewater under the Environmental Quality Act (Sewage) Regulations, 2009 that is safe to be released to the water body.

Abstract: Phosphorus is a non-renewable source and due to its high levels of phosphorus in water body may lead to eutrophication problems. It may come from many sources such as industry, agriculture and also from wastewater treatment plant. Large excessive of phosphorus may increase the purification cost and serious water quality problem because of the effect of algae toxin in water. Conventional wastewater treatment plant (WWTP) requires lot of cost such as labour, capital and maintenance costs. Therefore, the lab-scale aerated steel slag filter (ASSF) emerged as an alternative method to remove phosphorus from water due to its simple and also low cost technology has been developed to overcome this problem. This lab-scale filter has been conducted by using synthetic wastewater for an eight weeks starting from 19 March until 4^th May 2014. This study is to investigate the effect of pH range from 4.5 to 7.5 and temperature for phosphorus removal mechanism. From this study, result shows that lab-scale ASSF achieve about 90% of phosphorus removal at pH 5.0. Based on X-ray fluorescence (XRF) analysis, the steel slag is rich in Ca, Al and Fe which is enhance the P removal with the influence of pH for precipitation mechanism process in this experiment.

Abstract: Relationship between stakeholder influences and environmental management practices has not yet received sufficient attention in academic research in Malaysian fleet operations. Due to the increased awareness and concern among stakeholders for environmentally friendly business processes, the two main stakeholder influences including regulatory pressures and customer pressures are considered in combination to ensure firms to behave ethically and socially responsible. Environmental management practices including effectiveness of policy, effectiveness of implementation and effectiveness of planning in environmental management are one of the effective ways of dealing with environmental risks and costs. However, there is a little empirical research on how practitioners define and incorporate stakeholder influences into overall environmental management practices, particularly in the context of fleet operations. As such, this paper proposes a model to include two stakeholder influences and three environmental management practices. It is expected that this paper will offer useful guidance for future research scholars to empirically examine the relationship between stakeholder influences and environmental management practices for sustained business performance.

Abstract: There is national concern about rivers pollution degree. The Malaysian Department of Irrigation and Drainage (DID) is running a project for river biological purification using biomedia to reduce the river pollution degree. This study aims to use different types of biomedia carrier for effective management of the river purification plant project. Water samples were collected and tested for various essential parameters. A biomedia laboratory setup was fabricated for the research with seven different types of biomedia, and water sampling was collected daily and weekly for analysis purposes. The experimental results show that the best removal efficiency was achieved by biomedia Type 1 and was 88% and 65.5% for biochemical oxygen demand (BOD) and chemical oxygen demand (COD), respectively. Followed by biomedia Type 3 achieved an average of 58 percentage for ammonia (NH₃-N) removal. Overall, the best removal efficiency performance of biomedia Type 1 achieved the calculated rate of 68 %. The cleanest effluent was biomedia Type 4. For accumulated biofilm formation, the highest total volatile solid (TVS) was the biomedia Type 4. Finally, the best inclusive performance is biomedia Type 1. Future studies are recommended to conduct a pilot scale study with a longer time frame and to study these selective types of biomedia in anaerobic and anoxic condition.

Abstract: Rivers play a major role for communities especially in fisheries and as a source of water for people residing within the vicinity. Water quality is of utmost importance and it covers a wide range of approaches and conflicts. Water is super abundant on the planet, as whole, but fresh potable water is not always available at the right time or the right place for human or ecosystem use [3]. Water quality refers to the physical, chemical and biological characteristics of water. It is a measure of the condition of water relative to the requirements of one or more biotic species and or to any human need or purpose. It is most frequently used by reference to a set of standards against which compliance can be assessed. Sembrong dam reservoir was built by damming a river. When a reservoir is built along a river’s flow, the physical, chemical and biological conditions of the river are disrupted to some degree [2]. Since Sembrong dam reservoir is constructed on large lowland rivers with gradually sloping banks, it can be characterized by inundation of large areas, extreme horizontal variability with extensive shallows riparian vegetation and shallow reservoir. Such reservoir is usually eutrophic and high natural organic load are likely to contribute to the formation of an anoxic hypolimnion [9]. Shallow reservoir is usually well mixed by wind, and this leads to non-stratified condition [7]. Therefore, Sembrong dam reservoir can be categorized as shallow unstratified reservoir.

Abstract: Fly ash (FA) and bottom ash (BA) are some of waste generated by coal-fired power plants, which contains large quantities of toxic and heavy metals. The combustion of coal after been heated at specific temperatures and pressures in power stations produces ash. FA and BA must be properly managed and disposed without causing any harmful environmental effects. In recent years, many researchers have been interested to study on the properties of self-compacting concrete (SCC) incorporated with FA and BA but there was very limited research from the combination of FA and BA towards the environmental needs. Therefore, this study was focused in determining the leachability of heavy metals of SCC incorporated with FA and BA by using Synthetic Precipitation Leaching Procedure (SPLP). The samples were obtained from coal-fired power plant located at Peninsula, Malaysia. As such, the potential heavy metals leached out from SCC that is produced with FA as replacement for Ordinary Portland Cement (OPC) and BA as replacement for sand with the ratios from 10% to 30% respectively were designated and casted. There are eight heavy metals of concern such as As, Cr, Pb, Zn, Cu, Ni, Mn and Fe. The results show that all heavy metals were leached below the permissible limits from USEPA and EPAV except for As which is the only heavy metal that leaches in large amount even in the control specimen. This is probably due to the influence from the acidic extraction fluid, causing As to leach out in higher amounts during the extraction process. All in all, the uses FA and BA in SCC up to 20% seem to be an environmental friendly practice as far as leaching of heavy metals in the concrete is comply with the standard.

Abstract: Current pulp-processing in pulp and paper based industries are inefficient in removing the lignin as this compound is recalcitrant towards degradation. Transitioning from conventional pulping process into bio-delignification through utilisation of ligninase enzymes is one of the alternatives to improve the ability to fully utilize all components of wood to produce high quality fibres. Extensive research efforts have been focused on increase the production of ligninase enzymes from white rot fungi as a whole organism for industrial applications. However, enzymes activity produced from fungi are rather low as lignin modification is a secondary metabolism in which the enzyme only be expressed under particular conditions. Using genetic manipulations to incorporate genes associate for delignification isolated from different organisms such as tropical Asian wood-feeding insect into bacteria expression system will allow rapid enzyme production. This theoretical framework aims to produce an enzyme with high ligninase activity that will be used for removal of lignin during pulp-processing. These enzymes are thought to be more economically efficient in degrading lignin and involves less use of chemicals thus make this processing more environmentally friendly.Keywords: Biodelignification, Asian wood tropical insect, fungi, ligninase enzyme, bacterial expression system