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Managing urban garbage Conserving electricity Arms expert warns new mind drugs eyed by military
THIS UNIVERSE |
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Managing urban garbage Landfill is the ultimate method of disposal of waste, so the contents of landfill should be such that it contains, as far as possible, only the “ultimate” waste. To achieve this, we should start managing solid waste in a “totally scientific manner” involving the process of generation of waste, storage and collection, including its transportation, processing and disposal. The Integrated Medium Scale Waste Management Site, the case of the system developed at Banaswadi (Bangalore) has provision for segregation, composting of organic matter, incineration of the hospital waste, biogas plant and engineered landfill for solid waste. It is a very successful example. The sanitary landfill arrangement provided in Chandigarh since the late 1950s remained unaltered till recently. It comprised of dumping sites of Dhansa and Dadu Majra, located on the western boundary of the city. Here arrangements are made to receive the 350 tonnes of garbage generated daily by residents of City Beautiful. The garbage is brought to the site and dumped to be bulldozed into a thin layer, which is then given a thin spay of power lime and covered with soil and left to be affected by the hydrological cycle of rain, sunshine and weathering agents. The inert material present is not affected chemically but the organic fraction first is subjected to aerobic bio-degeneration, when mainly carbon dioxide gas is produced. This process continues till the oxygen present in the deposited fill lasts. Thereafter, the process of bio-degradation switches over to anaerobic degradation in which the gases produced being methane, ammonia and hydrogen sulphide and some carbon dioxide. Physical changes also occur in the stored mass on amount of movement of generated gases and this result in consolidation of the mass stored. It may be mentioned that mix of 5-15 per cent methane with air forms an explosive mixture and is seen to create trouble at landfill sites unless care is taken to ventilate and flare the escaping gases. On October 16, 2003, panic gripped Dadu Majra, when an explosion was heard and fire erupted in a heap of buried waste. Fire tenders took several hours to douse the flames. Thereafter, the smoke coming from the smouldering mass caused inconvenience to the residents living around the dump site. Tests on Chandigarh’s MSW showed that it has low organic content having calorific value less than 1000 kcal/kg about 800 kcal/kg. So, this material is fit for use in incineration with supplemental oil for power generation and not really suitable for fuel pelletisation. On July 31, 1996, the Municipal Corporation of Chandigarh signed an MoU with two firms, one from Delhi and other from Mumbai, for the compositing of MSW into manure. The MSW was to be supplied “free” at the plant site to the firms, but it was said that the Municipal Corporation would be given an annual “royalty” of Rs 19 lakh by the firm from MSW supplied. The firms were to set up a plant costing Rs 3.5 crore on the land made available to them. On July 8, 2005 the Municipal Corporation signed an MOU with Jai Prakash Associates to set up a garbage processing plant near the Dadu Majra dumping site. It was provided in the agreement that the company will complete the plant within 12 months after having given possession of land. The inauguration of the plant was officially done on December 27, 2008, almost 16 months after being given land it included four months of “grace” period. The estimated cost of the plant was Rs 23 crore. Until now, the company has not gone in full production, i.e., to process entire MSW produced by Chandigarh. So, a “show cause” notice was issued and R.K. Rao, Deputy Commissioner, Chandigarh, was entrusted with the inquiry. Recently, Rao submitted his report the major finding of which were that the company was absolved of any delay. It was observed that M/s Jai Prakash Associates “did not fail to operationalise the Dadu Majra garbage plant”, nor violated any term of the agreement. The report adds that the plant has started functioning and processing the solid waste supplied by the Municipal Corporation. However, the report agreed that the firm was not yet in position to process the entire volume of MSW produced by the city. It is also stated that the equipment installed at the site is not the same as provided in the DPR (detailed project report) and it is not clear as who granted the permission for the amendment and also questioned “Is the equipment installed is capable of performing the task envisaged i.e. to process 350 tonnes of MSW produced by Chandigarh daily”. The Chandigarh plant is first of its kind installed in India, which was required to process the entire volume of waste supplied to it. The difficulties being faced are such that it needs both sides to cooperate to make it work. But, will they do so is the question which needs to be asked. The residents wish to see the plant fully operational working 24x7 all the year around. On the other hand, we still need the old system of dumping till the above “miracle” occurs. Also, there is need to improve the management of dumping site, particularly regarding the control of gas emissions..
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Conserving electricity In today’s time, it is difficult to imagine life without electricity. Every time you turn the lights on, you create a little pollution. So, saving electricity doesn’t just put money in your pocket, it helps keep the air and water clean, too. In reality, this is pretty easy. All is required is to make some modest changes. Before I get to the tips on specific appliances, remember one simple thing, address the big energy-users first. You’ll save more electricity by dealing with the biggest electricity-guzzlers rather than worrying about items that don’t use much electricity. Worrying about whether it’s better to boil a cup of water on an electric burner or in a microwave, or whether you wear out your lights quicker by turning them off rather than keeping them on? That’s a waste of time and misses the point. Such trivia won’t make much of a difference in your electric bill. It’s the bigger things that matter. With that in mind, you’ll first want to address the big energy-users in your home first. But where does your home use energy and how much: air conditioning/heating—60 per cent, electric water heater—16 per cent, refrigerator—12 per cent, lighting—7 per cent, computer, TV, etc.—5 per cent. Here are the simple but effective strategies to save electrical energy, and money: l Use of double doors, automatic door closers, air curtains, double-glazed windows, polyester sun films, etc., reduces heat ingress and air-conditioning load of buildings. l
Utilisation of air-conditioned space should be examined and efforts be made to reduce cooling load as far as possible. l
Adjust thermostat setting of ad/heater. By turning down thermostat by just 1° centigrade, you can save up to 10per cent on electricity bills. l
Use solar water heater, instead of tank-type electric water heaters. l
Avoid frequent opening of refrigerator and freezer doors. l
Use oven for several items simultaneously. l
Use of electronic ballast in place of conventional choke saves energy up to 20 per cent. l
Use CFL lamp in place of GLS lamp. A 15W compact fluorescent lamp can replace a 60W regular lamp l
Clean the lamps and fixtures regularly, illumination levels fall by 23-30 per cent due to collection of dust. l
Use of 36W tube light instead of 40W tube light saves electricity by 8 to 10per cent. l
Use of sodium vapor lamps for area lighting in place of mercury vapour lamps saves electricity up to 40 per cent. l
Turn lights and appliances (TVs, computers, etc.) off when not in use l
You could use 30 per cent less energy in your home just by using energy more wisely and purchasing products with the Energy Star label. Remember, as you save, you will also be doing your bit to conserve electricity and helping the
envioronment.
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Arms expert warns new mind drugs eyed by military GENEVA: A leading expert on chemical and biological arms control called on Wednesday for urgent efforts to stop new mind-altering drugs developed for medical purposes from being adopted by the military for use in warfare. In an article in the U.S. journal Nature, British academic Malcolm Dando said civilian researchers in many countries seemed largely unaware of the danger and urged quick action to adapt a key arms pact to head it off. Gene experts see high-yield rice in flood zones HONG KONG: Researchers in Japan have identified two genes that make rice plants grow longer stems and survive floods, and hope this will enable farmers to grow high-yielding rice species in flood-prone areas. The long-stemmed deepwater rice varieties grown at present in areas of frequent flooding have very low yields. Deaths, lung damage linked to nano-particles HONG KONG: Seven young Chinese women suffered permanent lung damage and two of them died after working for months without proper protection in a paint factory using nano-particles, Chinese researchers reported on Wednesday. They said the study is the first to document health effects of nanotechnology in humans, although animal studies in the past have shown nano-particles could damage the lungs of rats. Cannabis chemicals may help fight prostate cancer LONDON:
Chemicals in cannabis have been found to stop prostate cancer cells from growing in the laboratory, suggesting that cannabis-based medicines could one day help fight the disease, scientists said Wednesday. After working initially with human cancer cell lines, Ines Diaz-Laviada and colleagues from the University of Alcala in Madrid also tested one compound on mice and discovered it produced a significant reduction in tumor growth.
— Reuters
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THIS UNIVERSE
I have filled a glass of water with cold water. After some time I found some water drop at the outer surface of the glass. Why? This is because the moisture in the air condenses on the cold glass surface. The principle is the same as that responsible for rain—rain is nothing but condensation of water vapour in the air that is cooled while rising to cold region of the upper atmosphere. Why does the sky and the surroundings appear to be red after rain at the time of sunset? At the time of sunset, the light from the sun has to travel a very long path through the atmosphere. This results in very strong scattering. Scattering of sunlight denudes it of shorter wave lengths, namely blue. Therefore closer to the sun’s direction we have a large dominance of the red. Such a spectacle is visible even when the atmosphere has not been washed clean by rain. If a magnet is a perfect sphere or a cube, where would the poles be? The magnets you are familiar with are produced by aligning the microscopic magnetic domains of a magnetic material. We assign magnetic moments even to individual charged particles whenever they have a spin angular momentum. Nuclei of atoms also have spins. Think of them as tiny magnets that, in a non-magnetised state of the bulk material, are randomly oriented. Magnetisation is a process of alignment. Therefore for a magnet in a spherical shape the poles would be positioned depending on the way it was magnetised. It might happen, though, that in an irregular shaped material, internal interaction between domains might produce a localised unpredictability in the magnetic field.
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On an average, each person produces 0.3 to 0.5 kg of solid waste daily, which needs to be collected and transported to a waste dumping site or disposal. At present, most Indian cities have dump sites of one homogenous mass of solid waste and this results in decreased life span of the landfill sites. So, there is need for an efficient mode of collection, removal and management of the solid waste without posing any health risk to workers engaged in its management.