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In This Issue ...
..................... ... .5 Forthcoming
Events ....... 6 Meeting
of the Committee on Engineering & Environment
....... 7 India Hosts - 2007 WFEO General Assembly World Congress ............ 7
Acronyms commonly used ........... 8
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Announcement : WEC
Forthcoming Conference Committee
Environmental Biotechnology for Sustainable Chemical Processing Dr M. P. Sukumaran Nair, FIE, India
The concern for a better environment all around by limiting our own reckless intervention in Nature to the utmost disadvantage of future generations have led to reorient the developmental process hitherto being adopted in an altogether different perspective which we now call the ‘sustainable’ manner. It is becoming increasingly aware that the bonds between human well being and social stability and natural processes are the most important linkages that sustain life on earth. This concern and its aftermath are reflected to a greater degree of awareness in the chemical processing industry as well. As environmental protection has become a global concern, the chemical industry is determined to re-examine conventional methodologies and seek ways of developing and applying more efficient and environmentally benign strategies for future sustainable growth. According to the Organization for Economic Cooperation and Development (OECD), industrial sustainability is the continuous innovation, improvement and use of clean technology to reduce pollution levels and consumption of resources. Sustainability in chemical processing involves the twin approaches of inherently safe design for plant/equipment and pollution prevention. Inherently safer designs Inherently safer process designs take care to reduce the presence of hazardous inventories (intensification), replace the hazardous materials with less hazardous ones (attenuation), use mild operating conditions of temperature, pressure, concentration etc during processing (moderation) or by restoring to a simpler design, easy to build and operate and therefore least prone to failures (simplification). Next
to inherent safe designs are attempts for source reduction of pollutants.
Reduction of Engineering design modifications is another method for reduction of pollutants at source. Extremes of temperature, pressure and concentration are reduced so as to render reactions to proceed in milder environments. Conversion of batch process to continuous process whereby recycle of streams is possible, application of emulsion breakers for effective separation, chemical synthesis from renewable sources rather than petrochemicals, use of different methods for handling reactants such as in the form of slurries, powders etc help to contain pollution at sources to a greater extent. Reduction of vents, spillages and emissions through improved instrumentation and better operating practices also result in reduced pollution loads to the environment. The third approach is abatement of pollution through control mechanisms involving chemical or biological processes. Chemical processes for controlling pollution such as neutralization, coagulation, flocculation, chemical decomposition etc are able to achieve certain limits of control achievable with available technology, are often costly and leave residues to the environment. It is at this point the biological methods of pollution control are most relevant. Biotechnology is an interdisciplinary discipline covering microbiology (study of micro-organisms) , biochemistry (science of chemical processes in living organisms) and engineering and uses living organisms for specific applications. Traditionally microbiologists have played a major role in the development of biological processes with the support from multiple disciplines including biochemistry, genetics and chemical engineering. It was Louis Pastuer’s work in 1857 that laid the foundation of modern biotechnology, when he discovered that fermentation occurred as a result of the biological activity of a microscopic plant called yeast. The scope of biotechnology has grown from simple wine fermentation to large scale industrial applications of not only beer, wine, cheese and milk production but also for the production of a variety of new products – antibiotics, enzymes, steroidal hormones, vitamins, sugars and organic adds and a host of other specialized applications. Today it is a multibillion-dollar global industry on the threshold of growth. According to the Biotechnology Industry Organization of the US , the industry tripled its revenue size from US $ 8 billion in 1993 to US $ 25 billion in 2001 and is set to achieve US $ 60 billion from the sale of biotech products by 2015. Biotechnological decomposition is achieved by the activity of microorganisms such as bacteria, fungus and algae and enzymes catalyze such reactions. The technology uses a set of tools developed to deal with cells and other objects (e.g., enzymes) derived from complex organisms in tissue culture. These tools would include isolation, manipulation and transfer of genetic material between cells. Benefits of biotechnology Biotechnology is used to assess the state of ecological systems, transform pollutants into benign substances, generate biodegradable materials from renewable sources, and develop environmentally safe manufacturing and disposal processes. Researchers are exploring biotechnological approaches to problem solving in many areas of environmental management and quality assurance, such as > Restoration of balance, structure and function of ecosystems; > Diagnostics, epidemiology and dispersal monitoring related to human disease agents; > Disease, pest and weed control in agriculture; > Contaminant detection, monitoring and remediation; > Toxicity screening, and > Conversion of waste to energy. The benefits of biotechnology are many and include providing resistance to crop pests, improve production and reduce use of toxic chemical pesticides, thereby making major improvements in food quality and environmental protection. Unlike the usual chemical processes, these reactions are characterized by low energy consumption and a low-level energy transaction, which means that very little energy inputs only are required and these reactions are carried out under mild conditions. For example, consider synthesis of ammonia to fix nitrogen from the atmosphere to make mineral fertilizers and photosynthesis the natural process of starch making. The former is an energy intensive chemical process, which is carried out in several stages involving large quantum of energy and higher-level energy transactions. The latter is a simple biochemical process by which green plants produce starch, an organic combination, out of inorganic substances like carbon dioxide and water using sunlight as source of energy under atmospheric conditions. The manufacture of ammonia leaves behind several pollutants – gaseous, liquid and solid – to the environment whereas the latter besides producing food consume substantial quantities of CO2. Biochemical and biotechnological processes have a higher degree of reaction efficiency, degradability and recyclability. Environmental biotechnology Environmental
biotechnology is not a new development at all. History dates the fine
application of biotechnology in waste treatment in 1914when bacteria were
used to treat sewage for the first time in Manchester, England.
Environmental biotechnology has since been applied most commonly to the
treatment of soil and wastewater and air pollution control.Composting and
wastewater treatment technologies are familiar examples of environmental
biotechnologies. However, recent developments in molecular biology,
ecology and environmental engineering now offer opportunities to modify
organisms so that their basic biological processes are more efficient and
can degrade more complex chemicals and higher volumes of waste materials.
New developments in environmental biotechnology help to the cleanup of
water and land areas polluted with petroleum products and other
harmful materials. It is the use of living micro organisms for a wide variety of applications in pollution control, environmental clean up and hazard waste management. It is preferred over waste disposal by the chemical processes because of the fact that in this mode of waste disposal pollutants generally are destroyed, so that no future cross-media transfers can occur. Bioscrubbers and boilers especially have been successful in the treatment of gaseous emissions. Another very successful application of environmental biotechnology has been in the treatment of petroleum wastes. Here the thrust is on waste reduction and waste elimination and at the same time achieving higher resource productivity. Natural processes operate like a closed system wherein every output is returned harmlessly to the ecosystem as a nutrient like compost or becomes an input for manufacturing another product. Thus in all the natural processes we see around us, least waste is generated and everything is recycled or degraded to the lowest level. Environmental biotechnology frequently uses living organisms – flora and fauna – engineered to exhibit specific traits in order to identify, control or prevent pollution. This technology has been applied to clean up hazardous waste sites more efficiently than conventional methods, thereby reducing the need for incineration or extraction-based methodologies. Bio-remediation has been applied to the cleanup of numerous varieties of pollutants, including heavy metals, explosives, sewage and industrial waste. Modern techniques of genetic engineering are essentially a refinement of the kinds of genetic modification that have long been used to enhance plants, microorganisms and animals for food. Researchers are bringing out more and more new organisms. The West addition to the growing list of bacteria that can sequester or reduce metals is Globate metallireducens, which removes uranium, a radioactive waste, from drainage waters in mining operations and from contaminated ground waters. Mechanism of working Microorganisms (primarily bacteria and fungi) are nature's original recyclers. Their capability to transform natural and synthetic chemicals into sources of energy and raw materials for their own growth suggests that expensive chemical or physical remediation processes might be replaced or supplemented with biological processes that are lower in cost and more environmentally benign. The mechanism of bioremediation is the natural process in which bacteria reduce organic substances to water and carbon dioxide. As available bacteria in nature are not always sufficient industrial bioremediation look for artificial environments for their culture and if required resort to genetic engineering techniques to build the required traits in them. There are two distinct ways by which remediation take place. In the first case nutrients are added to the site to be remedied to stimulate the activity of bacteria already present in the site. An alternate method is to add new bacteria with the specific remediation capabilities to the site. These organisms eat the contaminants at the site and thereby getting it rendered harmless. Once the waste concentration comes down either the bacteria population dies off or is reduced to normal population levels in the environment. Certain products of biodegradation such as methane gas etc are useful. Environmental control using biotechnology is specific to each application. The wide variety of pollutants that are degraded include fats, oil both mineral and natural, carbohydrates, protein etc. Pollutants compounds include benzene, toluene, ethyl benzene, Xylenes and complex aromatics such as naphthalenes, chloro compounds, gasoline, diesel, chlorinated benzenes and phenyls, and so on. In waste treatment processes improves efficiency, alleviates shock loading problems, controls odour and prevents problems in traps, pipes and drains by blockage etc. Biofiltration to remove VOCs from contaminated air using active microbial population is emerging as a promising and cost effective alternate method. It involves low capital and operating costs, low energy requirements and there are no left over residues. Recombinant microorganisms with expanded degradation capabilities have been developed recently. Researchers in several countries studied a number of microorganisms, each of which degraded a restricted range of pollutants, and characterized the genes involved. Investigators then combined genes from different species into one strain of bacteria that can degrade multiple types of pollutants. Similar applications of modern genetic techniques should make possible to tailor bacteria for bioremediation of sites contaminated with specific combinations of toxic compounds. Industrial applications Industrial processes where biotechnology can play a major role are agricultural processing, fertilizer, refinery and petrochemical, food, pharmaceutical, chemical, plastics, textile, paper, dyes, perfumery etc. Examples are numerous and to cite a few common applications we have the fermentation processes in food industry, production of medicine and of industrial chemicals, environmental purification of air, soil and water. The latter transposes waste substances into water and carbon dioxide gas, which is already contained in the air. The following are major industry effluents where the component pollutants are commonly treated by the biological method. Application of Biological Process for Pollution control
A direct impact of application of industrial and environmental biotechnology in the chemical industry is elimination of waste streams as such. The industry uses a series of biocatalysts to produce a variety of compounds with increased purity and reduced waste generation. Conventional petroleum based raw materials in plastic industry are giving way to renewable crops such as corn and soybeans to produce ‘green’ plastics. Toxic products, bad odour and colour from paper and pulp industry are reduced by use of enzyme-catalyzed process. Toxic effluent generation from fabric dyeing and finishing in textile industry is rendered harmless by the addition of enzymes to the active ingredients. Improved baking and fermentation process in the food industry by the use of enzymes increase food safety. In the livestock industry adding enzymes to cattle food reduces phosphate byproducts. Biosensors Yet another application of biotechnology in the interest of chemical industries is the field of environmental monitoring. The remarkable ability of microbes to break down pollutants is also useful in its detection. Diagnosis of environmental problems well in advance will be helpful to seek appropriate remedial measures to ward off its large-scale impacts. Methods are now available to detect soil contamination from organic pollutants using monoclonal antibodies. Antibody based biosensors can detect explosives and munitions underground. These methods besides being cheaper compared to chemical analysis involving costly equipment are faster and can be measured on site with the help of a portable instrument that gives out the result instantaneously. Case Studies Several case studies where bioremediation was resorted to successfully clean up the environment from contamination are available. To list a few: 1. Crude oil spill, Bemidji, Minnesota 2. Chlorinated solvents spill, New Jersey 3. Pesticides contamination of river streams, San Francisco Bay, Estuary 4. Gasoline contamination of ground water. Galloway, New Jersey 5. Creosote contamination of ground water, Florida 6. Agro chemicals contaminated ground water, Mid-continent US. Biotechnology also offer biofuels such as ethanol and bio-diese that have emerged as reasonable alternatives to the conventional petroleum fuels. These are of agricultural origin and can be easily blended with hydrocarbon fuels unto 50% blends and can be used in existing vehicles without any modifications. Biofuels are renewable resources, non-toxic, biodegradable and have reduced inflammability and their performance is also superior. Ethanol blended gasoline has become a commonplace fuel in many countries. Ethanol largely available as a by-product of the sugar industry is non-toxic and is thus environment friendly causing no harm to soil, water bodies and public health. Being an oxygenated fuel ethanol enhances the combustion of gasoline and effectively lowers emission rates from engines. Scope for further research Extensive scope for
research exists on the basic ecology of microorganisms and interactions
among microbial community members. In nature, microorganisms seldom exist
or act as single species; instead, they act collectively as consortia.
Research examining bioremediation of polychlorinated biphenyls (PCBs) in
the Hudson River, for example, revealed that both anaerobic and aerobic
bacteria, acting together, were responsible for degrading the pollutant.
Anaerobes The thrust areas are > Structure of microbial communities and their dynamics in response to normal environmental variation and novel anthropogenic stresses. > Biochemical mechanisms, including enzymatic pathways, involved in aerobic and particularly anaerobic degradation of pollutants. > Microbial genetics as a basis for enhancing the capabilities of microorganisms to degrade pollutants. > Microcosm/mesocosm studies of new bioremediation techniques to determine in a cost-effective manner whether they are likely to work in the field, and establish dedicated sites where long-term field research on bioremediation technologies can be conducted. > Innovative biotechnologies, such as biosensors, for monitoring bioremediation in situ; models for the biological processes at work in bioremediation; and reliable, uniform methods for assessing the efficacy of bioremediation technologies. Recent developments in biology have provided new tools and approaches for monitoring the environment and engineering organisms with the capacity to degrade environmental pollutants. Different types of organisms can be bioremediation agents. For example, the use of plants to concentrate pollutants (phytoremediation) is an emerging research area. In the field of biotechnology there is a seamless flow of basic research becoming directly applicable to humankind. Considering the enormous biodiversity and biological wealth in this country, basic research and modern biology, product oriented research for new generation of vaccines, diagnostics, recombinant products and other bio products specially the eco-friendly technologies would be the priority agenda for future. Biotechnology end Sustainable Development Both the Convention on Biological Diversity and the UN’s ‘‘Agenda 21’’ have acknowledged that biotechnology can be used to improve food security, healthcare and environmental protection and it has been publicly recognized as a necessary part of the vision for Sustainable Development (Chapter 16 of Agenda 21, the work programme) intended to implement the goals of the 1992 Rio Summit). Industrial and environmental biotechnology has unparalleled promise for the next phase of Sustainable Development.Representatives to the World Summit on Sustainable Development held recently at Johannesburg, South Africa have urged to help bring the benefits of biotechnology to less developed nations. "To meet the needs of the 8.3 billion people projected to be on this planet in 2025, the genetic improvement of food crops must include both conventional technology and biotechnology," commented Dr Norman Borlaug, the 1970 Nobel Peace Prize Laureate. Restoring the quality of the environment and safeguarding it from further degradation is another major task to be undertaken with the support of biotechnology and chemical engineers world over have a major responsibility to carry out this great mission. |
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pollution can be achieved through improvements in process
chemistry, reaction kinetics, stoichiometry, conversion and yields. This
is accomplished by using different types of physical forms of catalysts,
using water bound coatings instead of using volatile organic compounds (VOCs),
using oxygen instead of air and thus preventing side reactions, using
pigments and fluxes etc without containing heavy metals.
grow in the absence of oxygen, while aerobes require it. Further
research will provide a framework for understanding how microbial
communities respond to various environmental stresses; how to accelerate
in situ bioremediation by native microbial communities; and whether the
introduction of engineered microbes with enhanced bioremediation
potential can survive and function within established communities and help
remediate the site. Such studies are likely to provide corollary insights
into aspects of microbial biochemistry important for bioremediation as
well as the roles of microorganisms in biogeochemical cycling.