Showing posts with label Air Pollution. Show all posts
Showing posts with label Air Pollution. Show all posts

Wednesday, August 5, 2009

Industrial Air Pollution Worse Than Vehicle Exhaust For Breathing Problems In Children

Increasing numbers of children around the world are suffering from respiratory problems – coughing, wheezing and asthma attacks. Although the key external causes of these diseases were identified a long time ago (traffic and industrial air pollution), it had not previously been possible to distinguish clearly between these two factors so as to have a targeted impact on them.
Researchers at the Helmholtz Centre for Environmental Research (UFZ) and the University of Leipzig carried out research in this area together with colleagues from the University of La Plata and can now confirm that air pollution caused by industry has even more grave effects than vehicle exhaust fumes.
The recently completed study on 'Combined effects of airborne pollutants as risk factors for environmental diseases' was conducted as part of a long-standing collaborative venture, supported by the international office of the German Federal Ministry of Education and Research, between the Helmholtz Centre for Environmental Research (UFZ), the University of Leipzig and the University of La Plata in Argentina. The results have been published in several journals, including the Journal of Allergy and Clinical Immunology and Toxicology.
The UFZ researchers, who work in the Division of Health Research in Leipzig, concentrated on three courses of analysis: "Firstly," says Leipzig-based biologist Andrea Müller, "we used measurement techniques to draw accurate conclusions about the actual pollution of breathing air. We filtered out particulate matter of different grain sizes, polycyclic aromatic compounds, such as benzo(a)pyrene, that adhere to these particles, and volatile organic compounds, such as benzene and hexane. Secondly, we tested their toxic and mutagenic properties. We selected four comparative source regions: a residential area in the immediate vicinity of Argentina's largest oil refinery, an area with heavy traffic in the centre of La Plata, a suburban area and a rural area."
The children whose health formed the basis of the third course of analysis were selected from the same four areas. Around 1200 girls and boys aged between six and twelve were involved in the research that lasted about two years. With a parent-completed questionnaire data about the children's health symptoms were asked, such as coughs, wheezing, pneumonia and asthma attacks. Some of the children from each of the four regions were also invited to take a lung function test by the local paediatricians involved in the project. During the test the children were asked to blow into measuring devices – first hard and then slowly. This provided a measurement of the extent to which their bronchial tubes were constricted and therefore limited in function.
When all these measurements were concluded in La Plata at the end of 2006, thousands of pieces of data had to be compiled and correlated. It is possible to draw some notable conclusions from the columns of numbers and tables. They show, for instance, that the different respiratory disease symptoms in the industrial areas included in the study affect between a quarter and a third of all children. In the suburbs and in the countryside only half as many children tend to be affected and even in the city centre only around one or two per cent more children are affected than in the relatively unpolluted areas. The lung function of children from the industrial area was also significantly impaired. The researchers had not been expecting to find such a marked contrast.
Key culprits also appear to have been filtered out of the mass of pollutants. "Using novel statistical techniques, we identified the fingerprint of the industrial pollution in all sampled areas," says Leipzig-based meteorologist Dr. Uwe Schlink, explaining the analysis. "The level of the pollution, however, depends on the distance, season and weather situation. With an annual average of 20 micrograms of benzene per cubic metre air measured in the industrial areas of La Plata, but only 2.9 at traffic junctions in the city and 1.9 in rural areas, the health risk of industrial emissions is clear."
However, the research was about more than drawing scientific conclusions about which pollutants are the main cause of health problems. The researchers in Leipzig and their Argentinean colleagues in particular, were and still are working to raise public awareness of their research findings. They do this through parents' meetings at schools associated with the project and through lectures at the University of La Plata, through international publications and by lobbying government authorities and businesses. "At least we have helped change things for children in La Plata already," Andrea Müller is pleased to report: Because the chemical companies felt under pressure, they are now modernising their plants. "What would be interesting now would be to see how quickly the air pollution diminishes and to what extent children's health improves as a result. Whether the total mass of particulates or the number of particles per cubic centimetre is more important in terms of health problems and how we can influence climate impacts are also very topical questions," says physicist Dr Ulrich Franck. "In any case, we will continue to research these topics also in other cities around the world." link....

Industrial Air Pollution Worse Than Vehicle Exhaust For Breathing Problems In Children

Pine trees grown for 12 years in air one-and-a-half times richer in carbon dioxide than today's levels produced twice as many seeds of at least as good a quality as those growing under normal conditions, a Duke University-led research team reported Aug. 3 at a national ecology conference.
Carbon dioxide readings that high are expected everywhere by mid-century. The findings suggest some woody tree species could, in the future, out-compete grasses and other herbaceous plants that scientists had previously found can also produce more seeds under high-CO2, but of inferior quality."Even if both groups were producing twice as many seeds, if the trees are producing high-quality seeds and the herbaceous species aren't, then competitively you can get a shift," said Danielle Way, a Duke post-doctoral researcher.Way is scheduled to present the results at a poster session on Aug. 3 during the Ecological Society of America's 2009 annual meeting in Albuquerque, N.M. She is also first author of a report on the study scheduled for publication in the research journal Global Change Biology.Way and her co-researchers collected, counted and analyzed seeds produced at the Duke Free Air CO2 Enrichment (FACE) site in Duke Forest, near the university's campus. There, growing parcels of loblolly pine trees have been receiving elevated amounts of CO2 around the clock since 1997 in a Department of Energy-funded project designed to simulate natural growing conditions.
Their analysis found the high-CO2 loblolly seeds were similar in nutrient content, germination and growth potential to seeds from trees growing under present-day CO2 concentrations. "If anything, they actually seem to be slightly better seeds rather than more seeds of poorer quality," Way said."The notion here is that if the trees are producing more high-quality seeds at high CO2 compared to grasses and herbs, then the trees may be at an advantage," added study participant Robert Jackson. Jackson is Way's advisor at Duke, where he is a biology professor, as well as professor of global environmental change at the university's Nicholas School of the Environment.The ultimate competitive outcome will depend on how other trees comparatively respond to high-CO2, said James Clark, another Duke biology professor and Nicholas School professor of the environment who also participated in the study. "We don't know that yet, because we only have estimates for loblolly pines," Clark said. link....

Tuesday, August 4, 2009

Pollution Control

Air Pollution Control System.
Developed over the past couple years, the air pollution control system (IAPCS) is an integrated model which includes material balance in addition to the emission summary, preliminary design, and annualized cost estimate. Written in a C language and FORTRAN, it was made to be used on a compatible PC or an IBM. Its requirements are a 640k with lower RAM and require a 1.5 Mb space minimum. With updates completed at different times of its development, it seems to be held in different confidence levels with those involved. The purpose of the integrated air pollution control system is to estimate the control system costs for nitrogen oxide (NOx) and sulfur dioxide (SO2) in real-world utility plants, performing estimates of cost and performance. The costs are available in dollars amounts for any year for its output. This also involves costs for its first year and that of leveled costs, with the cost per unit of pollutant reduced. Many technologies can have its costs estimated through the new air pollution control system. With about 300 variables, the air pollution control system model includes coal analysis, boiler characteristics, pollution control design criteria, desired pollution control technologies, and economic assumptions. Default values in its parameter file in all areas, except the desired pollution control technology. This is a great advantage so the user is required only to supply units necessary for a specific analysis. The different technologies that can utilize the air pollution control system are the SO2 Control, the NOx Control, particulate matter, and combustion technologies with future users being able to include control regulators, utility companies, architect and engineering companies, legislators, and public utility commissions. The preliminary design of the air pollution control system includes its preliminary design with an output of capital cost estimate, emission summary, annualized cost estimate, material balance, capital charges with operation and maintenance expenses for 16 individual and combination control technologies. This design is applicable to coal-fired power plants, which range in 100-1300 Mwe of electric generating capacity.
DIFFERENT TECHNOLOGIES utilizing the integrated air pollution control system:• O2 controlo The wet flue gas desulfurizationo The process of lime spray dryingo Advanced silicate process, referred to as ADVACATEo A coal supply optiono Utilizing lime injection with dry sorbent injection• NOx control o Low NOx combustiono Natural gas re-burningo Selective catalytic reduction (SCR)o Selective non-catalytic reduction (SNCR)• Particulate Matter o Electrostatic precipitatoro Fabric filtero Gas conditioning (humidification and SO3)• Combustion Technologies o Atmospheric and pressurized fluidized-bed combustiono Integrated gasification combined cycle. link....