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Workshop onWorkshop on Everything is environmentally unclean Everything is environmentally unclean but overbut over criticism of CO2 is wrong criticism of CO2 is wrong

ByBy

Dr. Dr. Pooran KoliPooran Koli

Assistant ProfessorAssistant Professor Solar Power & Storage LabSolar Power & Storage Lab

Department of Chemistry, Jai Narain Vyas UniversityDepartment of Chemistry, Jai Narain Vyas University Jodhpur (Rajasthan) – 342033 INDIAJodhpur (Rajasthan) – 342033 INDIA

Approach of my talk

1. More as qualitative than quantitative2. Some supreme truths

3. Talking of clean industrial engineering and technology is just a myth but with some hope. Every technology is source of pollution like CO2 and difference is merely of relative ness.

4. Despite it to over criticize some technologies like thermal

power will be injustice to its significant role. Despite it to over criticize pollution like CO2 will be injustice

to its significant role. Pollution to some extent blessing in disguise.

5. What is/should be trend in research for development of cleaner technology?

6. The behavior of man is at the core of the environmental problems. Therefore, the human behavior and discipline must be an integral part of the any technology and policy aimed at environmental problems.

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1. Some supreme 1. Some supreme truthstruths

There are some supreme truths which nobody There are some supreme truths which nobody can deny.can deny.

- everyone has to die,- everyone has to die, - no activity can happen without the time & - no activity can happen without the time & energy.energy. - nothing is environmentally clean. Everything- nothing is environmentally clean. Everything ranging from biological to industrial activity isranging from biological to industrial activity is environmentally unsafe.environmentally unsafe. - - Punishment is rule of the nature. You do mistakes/carelessness, you are to suffer.

- disposal of once created pollutants only shifts - disposal of once created pollutants only shifts thethe

problemproblem

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2. How the talk of clean technology is a myth 2. How the talk of clean technology is a myth but with some hope?but with some hope?

We will discuss it by taking various examples We will discuss it by taking various examples – –more qualitative more qualitative - More focus on energy technology- More focus on energy technology because about 40 % CO2 pollution from energy technology,because about 40 % CO2 pollution from energy technology, because my research field is energy, so more versed with because my research field is energy, so more versed with

energy technologyenergy technology2.1. Coal fired thermal 2.1. Coal fired thermal power plantspower plants

Environmental impact of thermal Environmental impact of thermal power plantspower plants

- -Air pollution- heavy release of pollutants -Air pollution- heavy release of pollutants CO2,CO, SO2, NOx, etc.CO2,CO, SO2, NOx, etc.

- - Water pollution- Water pollution- - Deforestation- Deforestation- - Rehabilitation- Rehabilitation- - Land degradation, - Land degradation, - - Etc.- Etc.

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2.2. Towards cleaner coal technology2.2. Towards cleaner coal technology

IGCC, CTL, CCS AND REMOVAL OF POLLUTANTSIGCC, CTL, CCS AND REMOVAL OF POLLUTANTS

IGCC (Integrated gasification combined IGCC (Integrated gasification combined cycle) cycle) Coal- gaseous matter-cleaning-burningCoal- gaseous matter-cleaning-burning1.Coal burnt to produce syngas1.Coal burnt to produce syngas

2. Syngas burnt in combustor2. Syngas burnt in combustor

3. Hot gas drives gas turbines3. Hot gas drives gas turbines

4. Cooling gas heats water4. Cooling gas heats water

5. Steam drives steam turbines5. Steam drives steam turbines

Block diagram of IGCC Block diagram of IGCC plantplant

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IGCCIGCC technologytechnology - coal → coal → gaseous mixture (syn gas)→ gaseous mixture (syn gas)→ this gaseous mixture freed from harmful impurities → this gaseous mixture freed from harmful impurities → cleaned gas mix burnt to produce heat in turn electricity.cleaned gas mix burnt to produce heat in turn electricity.

- - coal burning in presence of O2(/or air) + steam under high coal burning in presence of O2(/or air) + steam under high temperature and pressure in a chamber → syngas (mainly a mixture of temperature and pressure in a chamber → syngas (mainly a mixture of CO +Hydrogen; other gaseous compounds like CH4,CO2, NO2, SO2, CO +Hydrogen; other gaseous compounds like CH4,CO2, NO2, SO2, N2, etc. )N2, etc. )

- During gasification, disposable glassy slag (due to solid inorganic During gasification, disposable glassy slag (due to solid inorganic impurities present in raw coal) is formed, which settles down in the impurities present in raw coal) is formed, which settles down in the chamber.chamber.

- Cleaning of syngas is done for removal of fly ash, sulphur compounds Cleaning of syngas is done for removal of fly ash, sulphur compounds and other pollutants. The metal oxide sorbents are used to absorb and and other pollutants. The metal oxide sorbents are used to absorb and remove H2S and COS at high temperature( 500 0C – 800 0C ). Sulfur remove H2S and COS at high temperature( 500 0C – 800 0C ). Sulfur and chlorine is removed by use of calcium hydroxide slurry followed and chlorine is removed by use of calcium hydroxide slurry followed by dry calcium hydroxide2.Particles are removed by filtration.by dry calcium hydroxide2.Particles are removed by filtration.

- The cleaned syngas is fired in gas turbine (much like natural gas) to The cleaned syngas is fired in gas turbine (much like natural gas) to generate hot gases which drives gas turbines to produce electricity. generate hot gases which drives gas turbines to produce electricity. The hot exhaust of the gas turbine is then used to generate steam for The hot exhaust of the gas turbine is then used to generate steam for use in conventional steam turbine generator to produce more use in conventional steam turbine generator to produce more electricity.electricity.

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IGCC……IGCC…… - This way IGCC results in improved efficiency( as electricity This way IGCC results in improved efficiency( as electricity

is obtained twice, first from gas turbine and then from is obtained twice, first from gas turbine and then from steam turbine), and lower emission of pollutants (like steam turbine), and lower emission of pollutants (like CO2,SO2,NO2,particulates,mercury,etc.).CO2,SO2,NO2,particulates,mercury,etc.).

- The reason for lower emission is that at high temperature, The reason for lower emission is that at high temperature, gasification process strips out impurities like sulphur, gasification process strips out impurities like sulphur, mercury, lead, cadmium,nitrogen, particulates, etc. and syn mercury, lead, cadmium,nitrogen, particulates, etc. and syn gas is then cleaned of gaseous forms of these impurities gas is then cleaned of gaseous forms of these impurities before its( syn gas ) burning.before its( syn gas ) burning.

- The pollutants like sulphur, mercury, etc. are converted The pollutants like sulphur, mercury, etc. are converted into gaseous pollutants which are removed from syn gas into gaseous pollutants which are removed from syn gas during its cleaning.during its cleaning.

- Thus, in comparison to pulverized coal power plants, the Thus, in comparison to pulverized coal power plants, the IGCC involves combined use of gas turbine and steam IGCC involves combined use of gas turbine and steam turbine for electricity generation, hence, the term turbine for electricity generation, hence, the term combined cycle is used in IGCC.combined cycle is used in IGCC.

- The gasification process can also produce syngas from high The gasification process can also produce syngas from high – sulphur coal, heavy petroleum residues and biomass.– sulphur coal, heavy petroleum residues and biomass.

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IGCC power plant versus pulverized coal based power plants : IGCC power plant versus pulverized coal based power plants :

superiority of IGCCsuperiority of IGCCEnvironment :Environment :

- The IGCC is a relatively cleaner coal technology because it is environmentally sustainable as emission of pollutants is very low in comparison to pulverized coal based power plants.

- In IGCC, CO2 emission can be further reduced by using oxygen instead of air for coal gasification.

- Use of oxygen leads to emission of CO2 in concentrated form Use of oxygen leads to emission of CO2 in concentrated form with high pressure enabling capturing and sequestering with high pressure enabling capturing and sequestering (separation of CO2 from emitted exhaust) of CO2 more easy and (separation of CO2 from emitted exhaust) of CO2 more easy and at lower cost. When coal gasification is done by air (which has at lower cost. When coal gasification is done by air (which has about 78% nitrogen) then emitted CO2 is diluted with nitrogen. about 78% nitrogen) then emitted CO2 is diluted with nitrogen. So, use of air makes capture of CO2 difficult and costly.So, use of air makes capture of CO2 difficult and costly.

- Efficiency : The fuel efficiency of IGCC ( about 45 %) is relatively higher than that of pulverized coal based plants ( about 35 %).

- Economic cost : The cost of an IGCC plant is 10-30% higher than that of a pulverized coal based power plant.

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………….IGCC.IGCC1.Coal burnt to produce syngas ,2. Syngas burnt in combustor, 3. Hot gas drives 1.Coal burnt to produce syngas ,2. Syngas burnt in combustor, 3. Hot gas drives

gas turbines,gas turbines,

4. Cooling gas heats water, 5. Steam drives steam turbines4. Cooling gas heats water, 5. Steam drives steam turbines

- Issue of O2,- Issue of O2,- Slag in place of ashSlag in place of ash- Metal sorbentsMetal sorbents

to absorb and remove to absorb and remove

H2S and COS at high temperatureH2S and COS at high temperature

( 500 0C – 800 0C )( 500 0C – 800 0C )- High tempHigh temp- Particles from filtrationParticles from filtration- Impurities not removed Impurities not removed

completelycompletely

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- Thus, IGCC has no zero emission. It only reduced to some extent. Thus, IGCC has no zero emission. It only reduced to some extent. Hence, no technology is clean technology. Every technology is Hence, no technology is clean technology. Every technology is associated with some pollution. So, IGCC is a cleaner technology associated with some pollution. So, IGCC is a cleaner technology but not clean technology.but not clean technology.

Emission Limits (lb/MMBtu)

IGCC Tradition coal fired

NOx 0.03 0.07

SO2 0.03 0.09

PM 0.011 0.013

CO 0.03 0.15

Hg lb/TBtu 0.5 0.66

Coal Type bituminous bituminous

CTL (Coal to Liquid Technology)CTL (Coal to Liquid Technology)

- It is a technology which provides for production of oil - It is a technology which provides for production of oil (diesel, naptha and other oil products) from coal. (diesel, naptha and other oil products) from coal. - The CTL technology will help in use of unextractable coal - The CTL technology will help in use of unextractable coal from earth, and of low quality E &F grade coal.from earth, and of low quality E &F grade coal. - This technology will not only help in end-use of coal but will - This technology will not only help in end-use of coal but will

also help in creating relatively clean (in comparison to coal)also help in creating relatively clean (in comparison to coal) fuels like diesel, naphtha and other products. fuels like diesel, naphtha and other products. -The CTL will help in control of pollution and also in meeting -The CTL will help in control of pollution and also in meeting increasing energy needs. CTL technology provides for both in-increasing energy needs. CTL technology provides for both in-

situ and ex-situ conversion of coal into liquid.situ and ex-situ conversion of coal into liquid.

  

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In theory, the entire present energy consumption of the world could be met by an area smaller than 1% of the world ’s deserts if they were covered with solar thermal electric plants.

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CCS (Carbon Capture and Storage)CCS (Carbon Capture and Storage)

-In spite of the improving efficiency of coal fired power stations, and use of IGCC and CTL

technologies, the CO2 emission remains a problem. To tackle this problem, the CCS technique

offers a hopeful strategy. The CCS involves prevention of green house gases from entering the atmosphere by capturing and storing CO2 (emitted from various

power plants) deep underground.

1.CO2 pumped into disused coal fields displaces methane which can be used as fuel2. CO2 can be pumped into and stored safely in saline aquifers3. CO2 pumped into oil fields helps maintain pressure, making extraction easier

Fig. Options for Carbon Capture and Storage

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- The use of coal as well as diesel, Petrol and naptha in - The use of coal as well as diesel, Petrol and naptha in commercial power plants,IGCC plants,other industries and commercial power plants,IGCC plants,other industries and domestic sector produces harmful pollutants like domestic sector produces harmful pollutants like

CO2,SO2,NO2,H2S and particulates.CO2,SO2,NO2,H2S and particulates. So there is need to control emission of these pollutants. So there is need to control emission of these pollutants.

There are number of ways for reduction of emission of There are number of ways for reduction of emission of these pollutants.these pollutants.

• Removal of SO2 and NO2 Removal of SO2 and NO2 : Power plants and many : Power plants and many industrial units produce flue gases (a mixture of NO2 industrial units produce flue gases (a mixture of NO2 and SO2). The NO2 and SO2 can be removed using and SO2). The NO2 and SO2 can be removed using scrubbing process in which flue gaseous mixture is scrubbing process in which flue gaseous mixture is treated with H2SO4 in presence of water. A sequence treated with H2SO4 in presence of water. A sequence of reactions between NO2, SO2, H2O and H2SO4 of reactions between NO2, SO2, H2O and H2SO4 produces removable H(NO)SO4. Thus we find that produces removable H(NO)SO4. Thus we find that SO2 and NO2 are removed in form of H(NO)SO4 from SO2 and NO2 are removed in form of H(NO)SO4 from flue gases which then is released into the atmosphere.flue gases which then is released into the atmosphere.

Removal of PollutantsRemoval of Pollutants

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* -* -Another more effective method is use of 'wet scrubbers' which Another more effective method is use of 'wet scrubbers' which

removes 99% of SO2 and NO2. The acidic SO2 reacts with removes 99% of SO2 and NO2. The acidic SO2 reacts with

calcium hydroxide - Ca(OH)2 - present in 'wet scrubbers' to calcium hydroxide - Ca(OH)2 - present in 'wet scrubbers' to

form gypsum (CaSO4), which is removed and used in the form gypsum (CaSO4), which is removed and used in the

construction industry. Magnesium hydroxide - Mg(OH)2 - can construction industry. Magnesium hydroxide - Mg(OH)2 - can

also be used in 'wet scrubber', which will remove SO2 also be used in 'wet scrubber', which will remove SO2

producing solid magnesium sulphate (MgSO4) which is producing solid magnesium sulphate (MgSO4) which is

separable and usable. Similarly, NO2 being acidic also reacts separable and usable. Similarly, NO2 being acidic also reacts

with Ca(OH)2 and Mg(OH)2 present in 'wet scrubbers'.This way with Ca(OH)2 and Mg(OH)2 present in 'wet scrubbers'.This way

NO2 is also separated using 'wet scrubber' from flue gases.NO2 is also separated using 'wet scrubber' from flue gases. * * Separation of particulatesSeparation of particulates : The particulates can be removed by : The particulates can be removed by

electrostatic method, fabric filter method, and wet particulate electrostatic method, fabric filter method, and wet particulate scrubbers. scrubbers.

The electrostatic precipitators can remove more than 99% of The electrostatic precipitators can remove more than 99% of particulates from the flue gases. The system works by creating an particulates from the flue gases. The system works by creating an electrical field to create a charge on particles which are then attracted electrical field to create a charge on particles which are then attracted by collection plates. by collection plates.

Removal of sulphurRemoval of sulphur : Sulphur present in coal emerges as SO2 and H2S : Sulphur present in coal emerges as SO2 and H2S gas which can be captured by processes ( wet scrubber, metal oxide gas which can be captured by processes ( wet scrubber, metal oxide sorbent, etc.) presently used in chemical industries.sorbent, etc.) presently used in chemical industries.

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Thus, the techniques like IGCC and CTL provide for use of coal in a Thus, the techniques like IGCC and CTL provide for use of coal in a relatively cleaner way. The use of techniques of 'CCS and removal of relatively cleaner way. The use of techniques of 'CCS and removal of pollutants' along with IGCC or CTL or coal fired power plants make use pollutants' along with IGCC or CTL or coal fired power plants make use of coal more cleaner. Actually, no coal technique is clean. We can of coal more cleaner. Actually, no coal technique is clean. We can make use of coal only cleaner. With use of techniques of IGCC, CTL, make use of coal only cleaner. With use of techniques of IGCC, CTL, CCS and removal of pollutants, we are definitely moving towards CCS and removal of pollutants, we are definitely moving towards cleaner coal technologies.cleaner coal technologies.

Emissions to air from plants with CCS

Pulverized coal

IGCC Combined

(+) increase or (-)decrease compared to a similar plant without CCS

CO2 -87 -88

NOx -99.7 +18

SOx +31 +11

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2.3. Nuclear reactor2.3. Nuclear reactor - Fission of U- Fission of U235235, Pu, Pu239239, U, U233233

- In isolation nuclear fuel produces no energy- In isolation nuclear fuel produces no energy

- Burning of fuel, no CO2- Burning of fuel, no CO2- But rest thing like mining, enrichment,- But rest thing like mining, enrichment, fabrication of reactor, concrete, iron,fabrication of reactor, concrete, iron, turbine, generator, etc. pollutingturbine, generator, etc. polluting

- Nuclear power is a CO2-free energy source at point of generation.Nuclear power is a CO2-free energy source at point of generation. Over the whole fuel cycle, nuclear power emits only 2–6 grams of Over the whole fuel cycle, nuclear power emits only 2–6 grams of carbon (or up to 20 grams of CO2) per kilowatt-hour of electricity carbon (or up to 20 grams of CO2) per kilowatt-hour of electricity produced. This is two orders of magnitude less than coal, oil and produced. This is two orders of magnitude less than coal, oil and natural gas, and is comparable to emissions from wind and solar natural gas, and is comparable to emissions from wind and solar power.power.

- A single nuclear power plant of one gigawatt capacity offsets the- A single nuclear power plant of one gigawatt capacity offsets theemission of some 7–8 million tonnes of CO2 each year if it displacesemission of some 7–8 million tonnes of CO2 each year if it displacescoal. A nuclear plant will also offset the emission of sulphur dioxide,coal. A nuclear plant will also offset the emission of sulphur dioxide,nitrous oxide and particulates, thereby contributing significantly tonitrous oxide and particulates, thereby contributing significantly toair quality.air quality.

- Nuclear power currently avoids the emission of 600 million tonnes of- Nuclear power currently avoids the emission of 600 million tonnes ofcarbon per year. If the world were not using nuclear power, CO2carbon per year. If the world were not using nuclear power, CO2emissions from electricity generation would be at least 17 per centemissions from electricity generation would be at least 17 per centhigher and 8 per cent higher for the energy sector overall. By 2030, thehigher and 8 per cent higher for the energy sector overall. By 2030, thecumulative carbon emissions saved due to the use of nuclear power could cumulative carbon emissions saved due to the use of nuclear power could

exceed 25 billion tonnes.exceed 25 billion tonnes.

..

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2.4 – Wind power 2.4 – Wind power - Itself wind is free and renewable but it alone cannot give powerItself wind is free and renewable but it alone cannot give power- We need pole, blades,turbine,etc., that is pollutingWe need pole, blades,turbine,etc., that is polluting- Also observed change in local wind pattern, and weakening of monsoon Also observed change in local wind pattern, and weakening of monsoon

locallylocally

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2.5- Hydro power

- three methods for generating hydroelectric energ- conventional method, the run-of-the river and the pumped storage.

- Dams are the sites that are most naturally used for the production of hydroelectricity

- Hydroelectric energy is the number one renewable energy source in the world and it accounts for about 6 per cent of the total production of electricity,

- The largest hydroelectric power station is located in China. The top 5 hydroelectric energy producing countries are: China, Canada, USA, Brazil and Russia. Norway produces about 99% of its electricity needs from hydropower.

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- Hydropower is considered to be 60% reliable.- As such Hydropower does not produce any CO2

emissions or any other gas pollutions.- But it needs cement, iron, steel, turbine whose production is

polluting; population displacement, damage to environment & fertile land, etc.

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2.6 SOLAR PHOTOVOLTAIC (SPV) TECHNOLOGY2.6 SOLAR PHOTOVOLTAIC (SPV) TECHNOLOGY

-Electricity can be produced directly from sunlight with the help of SPV -Electricity can be produced directly from sunlight with the help of SPV

technology. technology.

- SPV technology is based on the photovoltaic effect, which refers to - SPV technology is based on the photovoltaic effect, which refers to

transition of electrons from a lower to a higher energy state having transition of electrons from a lower to a higher energy state having

absorbed photons of the right energy. absorbed photons of the right energy.

- The photovoltaic effect is like photoelectric effect with a little - The photovoltaic effect is like photoelectric effect with a little

difference. difference. - - While in the photoelectric effect, electrons are ejected from the solid, While in the photoelectric effect, electrons are ejected from the solid,

liquid and gaseous elements when light strikes on the surface of liquid and gaseous elements when light strikes on the surface of these elements, in the photovoltaic phenomenon the electrons make these elements, in the photovoltaic phenomenon the electrons make a transition from a lower to a higher energy state having absorbed a transition from a lower to a higher energy state having absorbed photons of the right energy.photons of the right energy.

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PV…..PV…..- The SPV systems consists of two materials in contact with each other. - The SPV systems consists of two materials in contact with each other.

Among them, one is wafer of electron emitting non-metal and other Among them, one is wafer of electron emitting non-metal and other is electron collecting material which pass on electrons in form of is electron collecting material which pass on electrons in form of electron stream (i.e. current) to circuit. The electron emitting wafer electron stream (i.e. current) to circuit. The electron emitting wafer replenishes those electrons which goes out to circuit. replenishes those electrons which goes out to circuit.

- This technology involves semiconductors as light absorber, and This technology involves semiconductors as light absorber, and electronic species (electrons and positively charged holes) as mobile electronic species (electrons and positively charged holes) as mobile charges moving in device due to mainly drift ( under the influence of charges moving in device due to mainly drift ( under the influence of electric field) and some diffusion (under the influence of electric field) and some diffusion (under the influence of concentration difference).concentration difference).

- Point is that solar is free and renewable but it byitselfPoint is that solar is free and renewable but it byitself not produce electricity. For it, it needs panels, poles,not produce electricity. For it, it needs panels, poles,Batteries, etc. whose production and disposal is polluting.Batteries, etc. whose production and disposal is polluting.

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2.7. DYE- SENSITIZED SOLAR CELL TECHNOLOGY2.7. DYE- SENSITIZED SOLAR CELL TECHNOLOGY

-Point is that solar is free and renewable but it by itself-Point is that solar is free and renewable but it by itself

not produce electricity. For it, it needs dye, electrodes, electrolyte,not produce electricity. For it, it needs dye, electrodes, electrolyte,

Batteries, etc. whose production and disposal is polluting.Batteries, etc. whose production and disposal is polluting.

These cells are made up of a porous film of tiny (nanometer These cells are made up of a porous film of tiny (nanometer sized) white pigment particles made out of titanium dioxide. sized) white pigment particles made out of titanium dioxide.

The titanium dioxide particles are covered with a layer of dye, The titanium dioxide particles are covered with a layer of dye, which is in contact with an electrolyte solution. which is in contact with an electrolyte solution.

When solar radiation hits the dye, it injects a negative charge in When solar radiation hits the dye, it injects a negative charge in the pigment nanoparticle and a positive charge into the the pigment nanoparticle and a positive charge into the electrolyte resulting in the conversion of sunlight into electrical electrolyte resulting in the conversion of sunlight into electrical

energy.energy.

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2.8.PHOTOGALVANIC CELLS 2.8.PHOTOGALVANIC CELLS

Photogalvanic cells are galvanic cells which have property of Photogalvanic cells are galvanic cells which have property of solar energy conversion and storage.solar energy conversion and storage.

- This is the very simple technology on which I am working.- This is the very simple technology on which I am working.

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Photogalvanic cells….

-Point is that solar is free and renewable but it by -Point is that solar is free and renewable but it by itselfitself

not produce electricity. For it, it needs dye, not produce electricity. For it, it needs dye, electrodes, electrolyte,electrodes, electrolyte,

Batteries, etc. whose production and disposal is Batteries, etc. whose production and disposal is polluting.polluting.

2.9. Green chemistry – really not green but greener2.9. Green chemistry – really not green but greener

REACTANT (RAW MATERIAL) → PROCESS → PRODUCT → USE → REACTANT (RAW MATERIAL) → PROCESS → PRODUCT → USE → DISPOSALDISPOSAL

- Paul Anastas and John C. Warner developed 12 principles of green - Paul Anastas and John C. Warner developed 12 principles of green chemistry,which help to explain what the definition means in practice. chemistry,which help to explain what the definition means in practice. The principles cover such concepts as:The principles cover such concepts as:

* the design of processes to maximize the amount of raw material that * the design of processes to maximize the amount of raw material that ends up in the product;ends up in the product;

* the use of safe, environment-benign substances, including solvents, * the use of safe, environment-benign substances, including solvents, whenever possible;whenever possible;the design of energy efficient processes;the design of energy efficient processes;

* the best form of waste disposal: not to create it in the first place.* the best form of waste disposal: not to create it in the first place.

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The 12 principles of green chemistry are:The 12 principles of green chemistry are:

- - It is better to prevent waste than to treat or clean up waste after it is It is better to prevent waste than to treat or clean up waste after it is formed.formed.- - Synthetic methods should be designed to maximize the Synthetic methods should be designed to maximize the incorporation of all materials used in the process into the final incorporation of all materials used in the process into the final product.product.- Wherever practicable, synthetic methodologies should be designed - Wherever practicable, synthetic methodologies should be designed to use and generate substances that possess little or no toxicity to to use and generate substances that possess little or no toxicity to human health and the environment.human health and the environment.- - Chemical products should be designed to preserve efficacy of Chemical products should be designed to preserve efficacy of function while reducing toxicity.function while reducing toxicity.- The use of auxiliary substances (e.g. solvents, separation agents, - The use of auxiliary substances (e.g. solvents, separation agents, etc.) should be made unnecessary wherever possible and innocuous etc.) should be made unnecessary wherever possible and innocuous when used.when used.-- -- Energy requirements should be recognized for their environmental Energy requirements should be recognized for their environmental and economic impacts and should be minimized. Synthetic methods and economic impacts and should be minimized. Synthetic methods should be conducted at ambient temperature and pressure.should be conducted at ambient temperature and pressure.- A raw material or feedstock should be renewable rather than - A raw material or feedstock should be renewable rather than depleting wherever technically and economically practicable.depleting wherever technically and economically practicable.- - Reduce derivatives – Unnecessary derivatization (blocking group, Reduce derivatives – Unnecessary derivatization (blocking group, protection/deprotection, temporary modification) should be avoided protection/deprotection, temporary modification) should be avoided whenever possible.whenever possible.- Catalytic reagents (as selective as possible) are superior to - Catalytic reagents (as selective as possible) are superior to stoichiometric reagents.stoichiometric reagents.- - Chemical products should be designed so that at the end of their Chemical products should be designed so that at the end of their function they do not persist in the environment and break down into function they do not persist in the environment and break down into innocuous degradation products.innocuous degradation products.- Analytical methodologies need to be further developed to allow for - Analytical methodologies need to be further developed to allow for real-time, in-process monitoring and control prior to the formation of real-time, in-process monitoring and control prior to the formation of hazardous substances.hazardous substances.- Substances and the form of a substance used in a chemical process - Substances and the form of a substance used in a chemical process should be chosen to minimize potential for chemical accidents, should be chosen to minimize potential for chemical accidents, including releases, explosions, and fires.including releases, explosions, and fires.

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Green chemistry…..an exampleGreen chemistry…..an exampleFamily of polycarbonates very important polymers- made from Family of polycarbonates very important polymers- made from Bisphenol A & carbonyl chloride( or diphenyl carbonate).Bisphenol A & carbonyl chloride( or diphenyl carbonate). Carbonyl chloride is a very poisonous gas, Carbonyl chloride is a very poisonous gas, manufactured from other hazardous gases, manufactured from other hazardous gases, carbon monoxide and chlorine:carbon monoxide and chlorine:On the other hand, diphenyl carbonate is produced from dimethyl On the other hand, diphenyl carbonate is produced from dimethyl carbonate, carbonate,

which is readily manufactured which is readily manufactured from methanol, carbon monoxide from methanol, carbon monoxide and oxygen in the liquid phase, and oxygen in the liquid phase, in presence of copper(II) chloride, CuCl2:in presence of copper(II) chloride, CuCl2:Dimethyl carbonate, when heated with phenol in the liquid phase, Dimethyl carbonate, when heated with phenol in the liquid phase, forms the diphenyl carbonate.forms the diphenyl carbonate.

Overall, the process for the production of polycarbonate that uses Overall, the process for the production of polycarbonate that uses diphenyl carbonate is less hazardous than that using carbonyl diphenyl carbonate is less hazardous than that using carbonyl chloride.chloride.So the point is regarding green chemistry is that it is only relatively So the point is regarding green chemistry is that it is only relatively cleaner technology not clean.cleaner technology not clean.

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2.10. Other technology 2.10. Other technology

-You take any technology,it is unclean. If you make -You take any technology,it is unclean. If you make advancement in technology regarding cleaneer aspect, it will advancement in technology regarding cleaneer aspect, it will be less polluting but not clean at all.be less polluting but not clean at all.

- It is because from Ist law of Thermodynamics ,you cannot - It is because from Ist law of Thermodynamics ,you cannot make anything out of nothing. It means you make something, make anything out of nothing. It means you make something, you need raw material from nature, you need process for you need raw material from nature, you need process for production, you use product, you dispose off that, you recycle production, you use product, you dispose off that, you recycle it.it.-You do any activity you need energy- fuels-You do any activity you need energy- fuels- even the activity of talking, respiration, etc. is unclean.- even the activity of talking, respiration, etc. is unclean.- you start from wake up to going to bed, every activity is polluting.

Thus, I am of the opinion that nothing is environmentally unclean.Talking of clean industrial engineering and technology is just a myth but with some hope. Every technology is source of pollution like CO2 and difference is merely of relative ness.Don’t worry, we happy Despite it over criticism of pollution is wrong. We should see it in right perspective.

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3.

3. Despite it to over criticize some technologies like thermal power will be injustice to its significant role. Presently the fossils fuels like coal, etc. are over criticized. Everybody criticizing them. Non-renewable sourcesNon-renewable sources (e.g. fossil fuels- coal, petroleum, natural gas) are those (e.g. fossil fuels- coal, petroleum, natural gas) are those energy sources which cannot be renewed after use. energy sources which cannot be renewed after use. Beauty of Non-renewable sourcesBeauty of Non-renewable sources–– -Highly developed, -Highly developed, highly reliable, highly reliable, high energy density, high energy density, independent of seasonal & climatic variations, independent of seasonal & climatic variations, deep penetration in life, deep penetration in life, modern life owes to them, etc. modern life owes to them, etc. Thus, if they fail now you can imagine how the life will go Thus, if they fail now you can imagine how the life will go haywire.haywire. Limitations of Non-renewable sourcesLimitations of Non-renewable sources–– polluting, costly, limited in stock, less abundant, polluting, costly, limited in stock, less abundant, geographically unevenly distributed and fastly depleting, so geographically unevenly distributed and fastly depleting, so they cannot be safe and lasting source of energy.they cannot be safe and lasting source of energy.

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ductant.

4. Despite it to over criticize CO2 will be injustice to its significant role.

Carbon dioxide-An over blamed gasCarbon dioxide-An over blamed gas

The emission of CO2 pollutant is being held main culprit for The emission of CO2 pollutant is being held main culprit for excess Green House Effect (GHE) and in turn for global warming excess Green House Effect (GHE) and in turn for global warming and climate change.Because of this, CO2 has got dubious and climate change.Because of this, CO2 has got dubious distinction of being very harmful gas. Presently,CO2 is a most distinction of being very harmful gas. Presently,CO2 is a most hated gas. Today, CO2 is being seen even more dangerous than hated gas. Today, CO2 is being seen even more dangerous than fatal gases like Sarin (nerve gas). The CO2 has always been over fatal gases like Sarin (nerve gas). The CO2 has always been over blamed for harmful effects. But, I think that the over blaming of blamed for harmful effects. But, I think that the over blaming of CO2 for every environmental harm will be overlooking the CO2 for every environmental harm will be overlooking the significance of CO2 for life. CO2 has not only played role in significance of CO2 for life. CO2 has not only played role in creation of life on Earth but has also maintained the life by creation of life on Earth but has also maintained the life by indirectly feeding the animals, and by maintaining the indirectly feeding the animals, and by maintaining the inhabitable situations on Earth. The CO2 has also industrial inhabitable situations on Earth. The CO2 has also industrial significance.significance.

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A brief description of some of the significance of CO2 are as -A brief description of some of the significance of CO2 are as -

- CO2 and life origin- CO2 and life origin

According to current models of the origin of life , the first step towards According to current models of the origin of life , the first step towards origin of life was the formation of bio-chemicals like Amino origin of life was the formation of bio-chemicals like Amino Acids,Phospholipids, RNA, and Proteins .This hypothesis is based on Acids,Phospholipids, RNA, and Proteins .This hypothesis is based on ground that gaseous substances like N2 ,O2 ,H2 and CO2 were present ground that gaseous substances like N2 ,O2 ,H2 and CO2 were present in early time on Earth.The reactions among these gases led to formation in early time on Earth.The reactions among these gases led to formation of H2O,NH3 and CH4 which through the various stages of evolution led of H2O,NH3 and CH4 which through the various stages of evolution led to formation of bio-chemicals and origin of life on Earth.The basic to formation of bio-chemicals and origin of life on Earth.The basic chemicals from which life is thought to have formed are - chemicals from which life is thought to have formed are - CH4,NH3,H2O,H2S,CO2 or CO and PO4CH4,NH3,H2O,H2S,CO2 or CO and PO43+3+ . .

- CO2 and sustaining of life- CO2 and sustaining of life

It is only CO2 (no substitute for it ) which is feeding life on Earth through It is only CO2 (no substitute for it ) which is feeding life on Earth through the green plants which absorbs CO2 gas from the atmosphere to prepare the green plants which absorbs CO2 gas from the atmosphere to prepare their food (Carbohydrate ) and O2 by the process of photosynthesis. This their food (Carbohydrate ) and O2 by the process of photosynthesis. This way CO2 is essential for natural supply of food and O2 for sustaining way CO2 is essential for natural supply of food and O2 for sustaining life.life.

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- CO2 and Energy balance of Earth- CO2 and Energy balance of EarthFurther, the CO2 as part of green-house gases has Further, the CO2 as part of green-house gases has

important role in Green House important role in Green House Effect(GHE).Importance of GHE is that it traps Effect(GHE).Importance of GHE is that it traps solar energy on Earth’s surface and solar energy on Earth’s surface and atmosphere,and maintains the energy balance atmosphere,and maintains the energy balance on Earth by replenishing energy consumed by on Earth by replenishing energy consumed by plants in photosynthesis.Without GHE, the whole plants in photosynthesis.Without GHE, the whole Earth would be converted in to extremely cold Earth would be converted in to extremely cold planet and consequently life will not be able to planet and consequently life will not be able to have existence.Thus, GHE and in turn CO2 have existence.Thus, GHE and in turn CO2 makes Earth inhabitable.makes Earth inhabitable.

- CO2 and Industrial field & Medical field - CO2 and Industrial field & Medical field It is also to be noted that CO2 also finds applications in fire-It is also to be noted that CO2 also finds applications in fire-

extinguisher,manufacturing of aerated water, refrigeration as dry extinguisher,manufacturing of aerated water, refrigeration as dry ice (solid CO2), manufacturing of white lead (Pb) and baking ice (solid CO2), manufacturing of white lead (Pb) and baking soda, treatment of Pneumonia patients and victims of CO soda, treatment of Pneumonia patients and victims of CO poisoning as carbogen (a mixture of O2 with 5-10 per cent CO2).poisoning as carbogen (a mixture of O2 with 5-10 per cent CO2).

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With this description of significance of CO2, a question arises,why it is then most hated gas now ? The answer is that it is not CO2 but excess of CO2 which is being seen as playing the role of culprit. The excess CO2 in atmosphere is being seen as reason for excess GHE leading global warming and climate change as CO2 is a major green house gas. Here, it is to be mentioned that CO2 is unavoidable for life in same way as O2 , food ,and other essential materials are unavoidable for life. We know that O2 and food to a limit proves useful but their excess intake causes harm to life. Similarly, the CO2 up to a limit proves useful but its excess amount causes harm to life. So,we should take care that excess CO2 is removed from atmosphere as its excess amount is causing global warming and climate change.

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5. What is/should be trend in research for development of cleaner technology?

- The excess of pollution is really harmful. For sustainable life, we have to reduce it to a sustainable level.

- We should reduce it all/or most of the levels of input, process, product,use,disposal. This trend also going on.

We should use renewable sources like solar.Our focus is on mainly technology. But, for all ills of society and nature,

only human is culprit. All problem of globe like crime, murder,theft, boundary dispute,cheating,pollution,etc. are only because of man.

The behavior of man is at the core of the environmental problems. Therefore, the human behavior and discipline must be an integral part of the any technology and policy aimed at environmental problems.

Conclusion of my talk

1. Talking of clean industrial engineering and technology is just a myth but with some hope. Every technology is source of pollution like CO2 and difference is merely of relative ness.

2. Despite it to over criticize some technologies like thermal

power will be injustice to its significant role. Despite it to over criticize pollution like CO2 will be injustice

to its significant role. Pollution to some extent blessing in disguise.

3. Trend in research for development of cleaner technology should be to reduce at all/most of the stages of technology like input, process, product, use,disposal.

4. The behavior of man is at the core of the environmental problems. Therefore, the human behavior and discipline must be an integral part of the any technology and policy aimed at environmental problems.

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SOLAR CHIMNEY OR SOLAR TOWER Solar tower consists of a large greenhouse that funnels into a central tower. As sunlight shines on the greenhouse, the air inside is heated

and expands. The expanding air flows toward the central tower where a turbine converts the air flow into electricity. This technique is at

experimental stage. A 50 KW prototype was constructed (1981) in Ciudad Real, Spain and

operated for 8 years.

Thanks