Charging our handphones
CHARGING our handphones increases our electricity bill. Sure - mom never fails to remind everyone in the house to turn off the light in bedrooms, shut down computers, and switch off the aircons. Reminders to save electricity are everywhere - homes, offices, schools, factories. Just how much a month are we paying for the power we use and ‘pollute’?
Well, paying high bills is not all due to our electricity use. One of them is due to ‘pollution’ to the electrical supply system. Student Muhamad Taufiq Ramly of the Faculty of Electrical Engineering has re-constructed
a method, which was invented by lecturer Rahimi Baharom, that may help us reduce our electricity bill. Muhammad Taufiq has created a method to reduce the ‘pollution’ to electricity supply network which may have caused us the extra bill.
Conventional battery chargers of all portable devices and mass charging in factories usually introduce pollution within the power supply network. This pollution is in the form of impurities, scientifically called harmonic. Hence this means when we charge our handphones we are going to load the power system with harmonics, thus polluting the supply system network. As millions are charging handphones, the richer the harmonics be, the dirtier the supply gets. Dirty supply system incurs problems like power breakdown, higher consumption, greater loses of supply, overheating, extra energy use, lower performance, and finally higher electricity bill. Everyone will be affected.
But Muhammad Taufiq’s invention, an active power filter, will stop the ‘dirt’, assisting our charging not to pollute the power supply. He creates a measure to control the shape of the input waves, putting them back into its sinusoidal form, thus producing them smooth and clean of harmonics. As the shape of the polluted wave is changed into smoother ones the gadgets will introduce minimal harmonics.
The feature of Taufiq’s circuit is that it contains a single switch to provide an active power filter function. Most battery chargers we are using now employ filters. The active power filter here is used to mitigate the distorted current by injecting equal but opposite current to shape the pulsating of the supply current to a sinusoidal form. This is to ensure that the pulsating is in rhythm with the supply voltage. In this work, the single switch active power filter was used to reduce switching stress, losses and finally the cost. A boost converter concept was used as it would produce an output voltage greater than the input voltage. This condition makes the current flow to the inductor and thus fully charged. The energy stored in the inductor then can be used to compensate. When the switch is turned off, the diode is forward biased. The current would now flow through the inductor, diode, capacitor and load in a battery.
However, the inductor voltage reverses its polarity in an attempt to maintain its constant current. Due to the energy remains in the inductor, it is used to charge the capacitor and hence transfers the stored energy. As a result, output voltage is higher than the input voltage. Thanks to Taufiq and Rahimi, less worry when charging our handphones, we look forward to paying lower bill.
Information contacts:
Muhamad Taufiq Ramly
Rahimi Baharom
Faculty of Electrical Engineering
UiTM Shah Alam
taufiq.ramly@gmail.com
mie-2344@yahoo.com.my
Scaling the dye away
GIVE a poor man a fish, he eats for a day, teach him to fish he eats for a lifetime. Give a researcher a fish he will trade the scales. So folks, when cleaning the fish, do not throw the scales. Fish scales, seemingly useless they look, awfully smelly they be, they are valuable to scientist Hanafiah Zainal Abidin.
Taiwanese, Japanese and Chinese companies have been trading fish scales by millions of dollars. Traded for collagen and other materials for makeup products, it is about time Malaysia needs to save her fish scales. But in this case, Hanafiah is examining the use of fish scales to clean wastewater of batik factories.
Batik manufacturing is one of the largest industrial users of process water in especially extensive batik processing. Batik needs vibrant colours thus dyeing is its lifeline. To get sharp colours, manufacturers use concentrated dye, thus the dirtier the effluent is. Alas its drawbacks are that it will produce effluent filled with residual of dyes and chemical. The residual is with color, high pH, high Chemical Oxygen Demand (COD), and low biodegradability.
Thus in this case, cleaning the effluent needs a proper treatment before releasing it into the environment. In this study, coagulation-flocculation method for wastewater treatment will be applied. Polymeric coagulant produced from fish scale will be used in the process. This coagulant is tested for real wastewater from industry via jar tests.
The purpose of this research is to study the feasibility of fish scale as a source of cost effective coagulant for textile wastewater treatment. It is also to determine the optimize operating condition such as dosage and pH in textile wastewater treatment using fish scale.
With cheap raw material and polymeric content in fish scale, it is expected that economic treatment of textile wastewater could be established and biodegradable coagulant can be produced. Furthermore, production of coagulant from fish scale would enhance fishery activities.
The effluent from textile wet processing requires several treatment. Conventional activated sludge is able to remove large fractions of COD. Dye removal is most often achieved by sorption processes, rather than by biodegradation. For effluents with COD over 5000mg/l, anaerobic treatment becomes more significant. A combined anaerobic and aerobic treatment can also be effective to remove azodyes. However, this system removes dyes poorly; it is ineffective to decolorise textile effluent.
Removal of dyes is possible by activated carbon treatment. But it is expensive and the success depends on the type of dye and complete color removal is rarely achieved. Ozone is one of the strongest oxidizing agents readily available. It is used to reduce color, eliminate organic waste, reduce odour and reduce total organic in water. Ozone is one of the strongest commercially available oxidizers, making it popular for primary disinfection of potable water as well as for color and organic removal in wastewater applications. But, ozone cannot completely mineralize the organic dye to carbon dioxide and water even at high doses usage. This is due to the decolorisation rate decreasing with increasing initial dye color.
Up to date there is no economic and effective method to treat textile wastewater. Color from textile wastewater is hard to remove due to resistance of dyes to biological degradation where they are not readily degraded under the aerobic conditions prevailing in biological treatment plant. The color of textile effluent is unacceptable under Malaysian Environmental Regulation, besides the other parameter such as Chemical Oxygen Demand, Biological Oxygen Demand, and total iron.
Regulations for effluent and air emissions, however, are becoming increasingly stringent and more rigorously enforced, which prompt the industry to develop alternative methods for the management of process wastes. Due to these elements, balancing the environmental protection, economic viability and sustainable development is the biggest challenge in the textile industry. To keep the economic growing, a new way of treatment is vital to preserve the environment. To stay friendly to the environment, and not to create the wrath of nature, textile effluents need efficient treatment system.
One of the new treatment systems is coagulation. This method has been used to remove textile colors. Researchers claim that coagulation method using inorganic coagulants with an addition of polymer flocculant can remove colour almost 100%. Hence, as fish scale is found to contain adsorption ability, therefore, Hanafiah, in his work, will use the fish scale as coagulant. Up to date, there is no serious effort to use fish scales as a coagulant for wastewater treatment in Malaysia. Fish scales are thrown away as waste or used as fertilizers.
Thus the large amount of fish scale generated allows a good supply of biomaterial. The protein present in organic fraction in fish scale seem to be the major factor of adsorption ability. Other biomaterial in scales, such as chitosan, had proven its ability to remove dye where the charge neutralization in main mechanism for dye coagulation with chitosan is at acidic pH.
In this work, fish scales will be dried and ground before being added as coagulant in a powder form. An experimental study will be conducted on a local textile wastewater to assess the removal efficiency of the coagulation process. As we walk elegantly in our silk baju kurung, think of the fish scale.
Information contact:
Hanafiah Zainal Abidin
Faculty of Chemical Engineering
UiTM Shah Alam
hanafiah299@salam.uitm.edu.my
Slow down
AS automobiles industry expands, much has been debated about unnecessary casualties due to road accidents. At present the rate of road accident deaths in Malaysia hovers around 24 deaths per 100 000 people. Much deliberation and thoughts have taken place on how to reduce the rate of accidents, hence, Muhammad Akram Adnan and Mohd Jamaludin Md Noor are studying to reduce the speed of cars as speed and road accidents casualties have a strong relationship.
They are to develop a geometric standard for effective and ‘friendly’ hump speed reducer that considers human factor. Humans are sometimes good in judging the impact of height but otherwise in the impact of speed. Worse, many ignore road safety and do not care about others even when driving within a school area. Other impacts of high speed on the road are air pollution, noise level and traffic safety.
Another nature of road accidents in Malaysia is that the number will rise in festival seasons thus attention is always focused on deaths on the road during the three festivals: Hari Raya, Chinese New year and Deepavali. But in actual fact deaths and injuries occur all year round which include pedestrians. Investigation of road accidents show that when pedestrians are hit by cars at 30km/hr, 5% of them will be killed, most injuries are slight and 30% suffer no injury , but those hit by cars at 50 km/hr, 45% will be killed and many seriously injured, and at 65 km/hr 85% killed.
In this case, according to Muhammad Akram Adnan and Mohd Jamaludin Md Noor, the speed reducer works by transferring an upward force to a vehicle, as it traverses. The force translates it into vertical displacement and acceleration. The displacement induces a front to back pitching motion to the vehicle occupants. As speed increases the amplitude, i.e. the vertical displacement, and pitching also increase. The magnitudes of displacement and acceleration are the measure for the uncomfortable sensation.
For vehicle speed of less than 70 km/h this speed reducer is able to reduce speed less than the threshold value of 40 km/h, offer acceptable level of discomfort for vehicle occupants, avoid contact with vehicle base (thus no vehicle damage), and maximise overall road safety for road users.
Information contacts:
Muhammad Akram Adnan
Mohd Jamaludin Md Noor
Faculty of Civil Engineering
UiTM Shah Alam
akramuitm@yahoo.com
mohdjamaludin@salam.uitm.edu.my
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