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Showing posts with label clean technology. Show all posts
Showing posts with label clean technology. Show all posts

Thursday, July 17, 2008

Biotechnology for development of sustainable clean technology - Strategies:



Biotechnology for development of sustainable clean technology - Strategies:

Many developed countries started using biotechnology as a means of achieving clean or cleaner industrial products and processes. It compares biotechnological processes with competing means of securing similar goals.


Meaning of Clean technology - All stages of the life cycle of a product or process may adversely affect the environment by using up limited resources of materials and energy or by creating waste. Any substitution or change that reduces consumption of materials and energy and production of waste – including, for example, recycling of materials and energy – may be regarded as more environmentally friendly or ‘‘clean’’. Clean technology may also be equated with reduced risk.


Life Cycle Assessment is one way of comparing the relative cleanliness of a product or process.


Cleaner processes and products mean processes and products that consume less energy and material resources, generate less pollution or waste, or use renewable resources rather than petroleum or coal-based feedstock as feed. There are many reasons why an operator would switch to a cleaner process or product. Some of the more important factors most often mentioned are:

(a) Availability of raw materials;

(b) Cost factors;

(c) Market demands;

(d) Safety and health considerations;

(e) Environmental considerations;

(f) Product liability;

(g) Public image.


Thus, it is the duty of developed countries to appreciate the potential role of biotechnology in clean industrial processes and sets the stage for viewing clean processes in the context of industrial sustainability. The extents to which biotechnological thinking and practices are being introduced into industrial sectors, which have serious environmental impacts, are to be enhanced. The economic competitiveness of biotechnology for clean products and processes in these sectors are the major concerns, which Government / authorities required to be take a note and policy implementation should be in tune with sustainable development.


Scientific and technological innovations across the range of biotechnologies and the opportunities for their adoption, as well as R&D priorities are to be spelt out.


The following few points are to be kept in mind while framing strategies for promotion of biotechnology for development of clean technology, in the context of industrial sustainability:


(a) Global environmental concerns will drive increased emphasis on clean industrial products and processes.


(b) Biotechnology is a powerful enabling technology for achieving clean industrial products and processes that can provide a basis for industrial sustainability.


(c) Measuring the cleanliness of an industrial product or process is essential but complex; Life Cycle Assessment (LCA) is the best current tool for making this determination.


(d) The main drivers for industrial biotechnological processes are economic (market forces), government policy, and science and technology.


(e) Achieving greater penetration of biotechnology for clean environmental purposes will require joint R&D efforts by government and industry.


(f) For biotechnology to reach its full potential as a basis for clean industrial products and processes, beyond its current applications, additional R&D efforts will be needed.


(g) Because biotechnology, including recombinant DNA technology and its applications, has become increasingly important as a tool for creating value-added products and for developing biocatalysts, there is a strong need for harmonised and responsive regulations and guidelines.


(h) Market forces can provide very powerful incentives for achieving environmental cleanliness objectives.


(i) Government policies to enhance cleanliness of industrial products and processes can be the single most decisive factor in the development and industrial use of clean biotechnological processes.


(j) Communication and education will be necessary to gain penetration of biotechnology for clean products and processes into various industrial sectors.

Sunday, June 29, 2008

Biotechnology to address many global environmental concerns:


Biotechnology to address many global environmental concerns:

A. Industrial biotechnology has come of age. Improved industrial sustainability through biotechnology addresses many global environmental concerns. Biotechnology has clear environmental advantages and is economically competitive in a growing number of industrial sectors. It enables reductions of material and energy consumption, as well as pollution and waste generation, for the same level of industrial production. Continued technical innovation, including that based upon recombinant DNA technology, is vital for the wider utilisation of biotechnology by industry.


B. With biotechnology, the emphasis is no longer on the removal of pollutants from an already damaged environment, but on the need to reshape industrial process technologies to prevent pollution at the source. Achieving ‘‘clean technology’’ or ‘‘industrial sustainability’’ – the two terms are largely congruent – will not be possible without a steady stream of creative innovations based on advanced science and technologies, among which biotechnology is likely to play an increasing role.


C. Although definitions of sustainable development have frequently proved elusive, it is clear that any move towards industrial sustainability will affect all stages of a product’s or process’s life cycle. It will require new design principles based on a global and holistic approach to reducing environmental impacts: global because these impacts transcend national borders, holistic because short-term, piecemeal solutions to address a succession of issues in isolation will be less and less effective. One important means of integrating environmental issues into industrial design and operations is the adoption of Life Cycle Assessment (LCA).


D. There are three main drivers of clean technology:

(a) Economic competitiveness, with companies considering the advantages of clean products and processes in terms of market niches or cost advantages;

(b) Government policies, which enforce or encourage changes in manufacturing practices; and

(c) Public pressure, which takes on strategic importance as companies seek to establish environmental legitimacy.


E. It is possible to foresee a growing role for industrial process biotechnology, both because it may afford clear economic and environmental benefits, and because the power of the tool itself continues to grow. The expectations of greater cleanliness come from the observation that living systems manage their chemistry rather more efficiently than man-made chemical plants, and that their wastes tend to be recyclable and biodegradable. This, along with our increasing ability to manipulate biological materials and processes, strongly points to a significant impact on the future of manufacturing industries.

F. Here there is a brief picture of how modern process biotechnology is penetrating industrial operations:

(i) Biotechnology embraces a wide range of techniques, and none of these will apply across all industrial sectors. Nonetheless, the technology is so versatile that many industries that have not used biological sciences in the past are now exploring the possibility of doing so. Already, the economic competitiveness of a variety of biotechnological applications to achieve cleanliness has been established. This is essential, as environmental benefits alone have seldom driven the adoption of biotechnology-based processes. Such processes have been successfully integrated into some large-scale operations. However, a number of problems remain for industrial applications, particularly the entrenched infrastructure of companies that have traditionally relied on physical and chemical technology alone and whose engineers have no training in life sciences or technologies.

(ii) Chemicals manufacturing is a major generator of materials, a major consumer of energy and non-renewable resources, and a major contributor to waste and pollution. In these sub-sectors, market penetration of biotechnology varies. It is in the fine chemical industries that the impact of clean biotechnology is most visible.


(iii)While fossil carbon (oil, coal) is the single most important raw material for energy generation and for chemicals, the concomitant CO2 emissions are a source of increasing concern because CO2 is a major greenhouse gas. Biotechnology can contribute to reducing fossil carbon consumption and hence global warming in various ways: improving industrial processes and energy efficiency, and producing biomass-based materials and clean fuels.


(iv) In pulp and paper, market penetration of biotechnology used for clean production is particularly high in many of the developed nations, and biotechnology is becoming more important in the manufacture of textiles and leather throughout the western world.


(v) In the food and feed sector, the impact of biotechnology on clean industrial processes seems to be greatest in the United States.

(vi) Biotechnology for mining and metals recovery covers two major technologies: bioleaching/minerals bio-oxidation, where superior cleanliness and economic profitability have been claimed in specific cases, and metals bioremediation and recovery.

(vii) In the energy sector, biotechnology has had a major effect both on economics and on environmental impacts. It has improved the overall efficiency of processes, particularly in the area of pollution control. Processes currently under development, such as bio-diesel, bio-ethanol and bio-desulphurisation, seek to replace energy-intensive and polluting systems with systems that are more environmentally friendly. The effect of rDNA methods on these technologies will be great, but large-scale application of rDNA has only recently begun and has not yet had dramatic effects.


G. Although the potential of biotechnology to reduce raw materials and energy consumption as well as wastes is attractive, there is a need for further encouragement, notably by government, particularly when the economic advantages are not overwhelming in the early stages of adoption.

Monday, March 10, 2008

Environment-friendly Hydrogen gas as fuel in fuel cell and its challenges:


Environment-friendly Hydrogen gas as fuel in fuel cell and its challenges:

Hydrogen is the simplest and lightest element. Storage is one of the greatest problems for hydrogen. It leaks very easily from container meant for storage, no mater how strong and no matter how well insulated. Therefore, hydrogen in storage tanks always evaporates, at a rate of at least 1.7 percent per day.

Another important property of hydrogen is it is very reactive in nature. When hydrogen gas comes into contact with metal surfaces it decomposes into hydrogen atoms, which are so very small that they can penetrate metal. This causes structural changes that make the metal brittle.

One of the largest problems perhaps hydrogen fuel cell transportation has is its fuel tank size. In gaseous form of hydrogen, a volume of 238,000 litres gas is necessary to replace the same energy capacity of 20 gallons of petrol (gasoline). One option is to compress the gas. Because of gas’s low density property, compressed gas does not give a car as useful a as of gasoline as far as storage volume is concerned. Moreover, a compressed hydrogen fuel tank would be at risk of developing pressure leaks either through accidents or through normal wear and such leaks could result in dangerous explosions.

In case, the hydrogen is liquefied, the liquid hydrogen would give a density of 0.07 grams per cubic centimeter. In that case, it may require almost the four times volume of gasoline for a given amount of energy release. Besides, there are many difficulties in storing liquid hydrogen. Liquid hydrogen is cold enough to freeze air. Accidents may occur from pressure build-ups resulting from plugged valves. Besides, energy costs of liquefying the gas and refrigerating it also to be considered while calculating economy.

Other option may be considered is the use of powdered metals to store the hydrogen in the form of metal hydrides. The volume of stored metal hydrides would be little more than that of the metals themselves; but storing in this form, hydrogen would be far less reactive. However, the weight of the metals will make the storage tank very heavy.

As far as production of hydrogen is concerned, hydrogen does not freely occur in nature in useful quantities. Therefore hydrogen must be split from molecules, either molecules of methane derived from fossil fuels or from water. Currently, most hydrogen is produced by the treatment of methane with steam (the equation is CH4 (g) + H2O + e > 3H2(g) + CO(g)). The CO(g) in this equation is carbon monoxide gas, which is a byproduct of the reaction. Again the production of CO, which converts into CO2 is a greenhouse gas – not environment friendly option. Again, at present we do not have viable technology to obtain hydrogen from water, other than electrolysis – which is not energy saving option.

Therefore, as of now, it is a challenge before us to use hydrogen economically, efficiently and environment-friendly way. As lot research activities are going on in this field, very soon positive favorable result could be seen.

Principle of Hydrogen fuel cell:

The hydrogen fuel cell is an electrochemical energy conversion device. Hydrogen and oxygen are fed into opposite sides of a cell, which are separated by a membrane permeable to hydrogen ions but not electrons. Hydrogen gas molecules entering the anode side of the cell are ionized in the presence of a catalyst to form protons and electrons. The protons pass through the membrane to combine with the oxygen and electrons to produce water at the cathode. The electrons flow through an external circuit from the anode to the cathode, creating an electrical current, which powers an electric load such as a motor.