Myth and Hope of Clean Technology: Everything is Environmentally Unclean, but Over-Criticism of CO2 is Wrong

1. Workshop on Everything is environmentally unclean but over criticism of CO2 is wrong By Dr. Pooran Koli Assistant Professor Solar Power & Storage Lab Department of Chemistry, Jai Narain Vyas University Jodhpur (Rajasthan) – 342033 INDIA

2. Approach of my talk 1. More as qualitative than quantitative 2. 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.

3. 1. Some supreme truths There are some supreme truths which nobody can deny. - everyone has to die, - no activity can happen without the time & energy. - nothing is environmentally clean. Everything ranging from biological to industrial activity is environmentally unsafe. - Punishment is rule of the nature. You do mistakes/carelessness, you are to suffer. - disposal of once created pollutants only shifts the problem 3

4. 2. How the talk of clean technology is a myth but with some hope? We will discuss it by taking various examples –more qualitative - More focus on energy technology because about 40 % CO2 pollution from energy technology, because my research field is energy, so more versed with energy technology 2.1. Coal fired thermal power plants Environmental impact of thermal power plants -Air pollution- heavy release of pollutants CO2,CO, SO2, NOx, etc. - Water pollution - Deforestation - Rehabilitation - Land degradation, - Etc. 4

5. 2.2. Towards cleaner coal technology IGCC, CTL, CCS AND REMOVAL OF POLLUTANTS IGCC (Integrated gasification combined cycle) Coal- gaseous matter-cleaning-burning 1.Coal burnt to produce syngas 2. Syngas burnt in combustor 3. Hot gas drives gas turbines 4. Cooling gas heats water 5. Steam drives steam turbines Block diagram of IGCC plant 5

6. IGCCtechnology • coal → gaseous mixture (syn gas)→ this gaseous mixture freed from harmful impurities → cleaned gas mix burnt to produce heat in turn electricity. - coal burning in presence of O2(/or air) + steam under high temperature and pressure in a chamber → syngas (mainly a mixture of CO +Hydrogen; other gaseous compounds like CH4,CO2, NO2, SO2, N2, etc. ) • During gasification, disposable glassy slag (due to solid inorganic impurities present in raw coal) is formed, which settles down in the chamber. • Cleaning of syngas is done for removal of fly ash, sulphur compounds and other pollutants. The metal oxide sorbents are used to absorb and remove H2S and COS at high temperature( 500 0C – 800 0C ). Sulfur and chlorine is removed by use of calcium hydroxide slurry followed by dry calcium hydroxide2.Particles are removed by filtration. • The cleaned syngas is fired in gas turbine (much like natural gas) to generate hot gases which drives gas turbines to produce electricity. The hot exhaust of the gas turbine is then used to generate steam for use in conventional steam turbine generator to produce more electricity.

7. IGCC…… This way IGCC results in improved efficiency( as electricity is obtained twice, first from gas turbine and then from steam turbine), and lower emission of pollutants (like CO2,SO2,NO2,particulates,mercury,etc.). The reason for lower emission is that at high temperature, gasification process strips out impurities like sulphur, mercury, lead, cadmium,nitrogen, particulates, etc. and syn gas is then cleaned of gaseous forms of these impurities before its( syn gas ) burning. The pollutants like sulphur, mercury, etc. are converted into gaseous pollutants which are removed from syn gas during its cleaning. Thus, in comparison to pulverized coal power plants, the IGCC involves combined use of gas turbine and steam turbine for electricity generation, hence, the term combined cycle is used in IGCC. The gasification process can also produce syngas from high – sulphur coal, heavy petroleum residues and biomass. 7

8. IGCC power plant versus pulverized coal based power plants : superiority of IGCC 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 with high pressure enabling capturing and sequestering (separation of CO2 from emitted exhaust) of CO2 more easy and at lower cost. When coal gasification is done by air (which has about 78% nitrogen) then emitted CO2 is diluted with nitrogen. 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. 8

9. …….IGCC 1.Coal burnt to produce syngas ,2. Syngas burnt in combustor, 3. Hot gas drives gas turbines, 4. Cooling gas heats water, 5. Steam drives steam turbines - Issue of O2, Slag in place of ash Metal sorbents to absorb and remove H2S and COS at high temperature ( 500 0C – 800 0C ) High temp Particles from filtration Impurities not removed completely 9

10. Thus, IGCC has no zero emission. It only reduced to some extent. Hence, no technology is clean technology. Every technology is associated with some pollution. So, IGCC is a cleaner technology but not clean technology. 10

11. CTL (Coal to Liquid Technology)- It is a technology which provides for production of oil (diesel, naptha and other oil products) from coal. - The CTL technology will help in use of unextractable coal from earth, and of low quality E &F grade coal.- This technology will not only help in end-use of coal but will also help in creating relatively clean (in comparison to coal)fuels like diesel, naphtha and other products. -The CTL will help in control of pollution and also in meeting increasing energy needs. CTL technology provides for both in-situ and ex-situ conversion of coal into liquid. 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. 11

12. 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 fuel 2. CO2 can be pumped into and stored safely in saline aquifers 3. CO2 pumped into oil fields helps maintain pressure, making extraction easier Fig. Options for Carbon Capture and Storage

13. Removal of Pollutants - The use of coal as well as diesel, Petrol and naptha in commercial power plants,IGCC plants,other industries and domestic sector produces harmful pollutants like CO2,SO2,NO2,H2S and particulates. So there is need to control emission of these pollutants. There are number of ways for reduction of emission of these pollutants. • Removal of SO2 and NO2 : Power plants and many industrial units produce flue gases (a mixture of NO2 and SO2). The NO2 and SO2 can be removed using scrubbing process in which flue gaseous mixture is treated with H2SO4 in presence of water. A sequence of reactions between NO2, SO2, H2O and H2SO4 produces removable H(NO)SO4. Thus we find that SO2 and NO2 are removed in form of H(NO)SO4 from flue gases which then is released into the atmosphere.

14. * -Another more effective method is use of 'wet scrubbers' which removes 99% of SO2 and NO2. The acidic SO2 reacts with calcium hydroxide - Ca(OH)2 - present in 'wet scrubbers' to form gypsum (CaSO4), which is removed and used in the construction industry. Magnesium hydroxide - Mg(OH)2 - can also be used in 'wet scrubber', which will remove SO2 producing solid magnesium sulphate (MgSO4) which is separable and usable. Similarly, NO2 being acidic also reacts with Ca(OH)2 and Mg(OH)2 present in 'wet scrubbers'.This way NO2 is also separated using 'wet scrubber' from flue gases. * Separation of particulates : The particulates can be removed by electrostatic method, fabric filter method, and wet particulate scrubbers. • The electrostatic precipitators can remove more than 99% of particulates from the flue gases. The system works by creating an electrical field to create a charge on particles which are then attracted by collection plates. • Removal of sulphur : Sulphur present in coal emerges as SO2 and H2S gas which can be captured by processes ( wet scrubber, metal oxide sorbent, etc.) presently used in chemical industries.

15. 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 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 make use of coal only cleaner. With use of techniques of IGCC, CTL, CCS and removal of pollutants, we are definitely moving towards cleaner coal technologies.

16. 2.3. Nuclear reactor - Fission of U235, Pu239, U233 - In isolation nuclear fuel produces no energy - Burning of fuel, no CO2 - But rest thing like mining, enrichment, fabrication of reactor, concrete, iron, turbine, generator, etc. polluting • 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 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 natural gas, and is comparable to emissions from wind and solar power. - A single nuclear power plant of one gigawatt capacity offsets the emission of some 7–8 million tonnes of CO2 each year if it displaces coal. A nuclear plant will also offset the emission of sulphur dioxide, nitrous oxide and particulates, thereby contributing significantly to air quality. - Nuclear power currently avoids the emission of 600 million tonnes of carbon per year. If the world were not using nuclear power, CO2 emissions from electricity generation would be at least 17 per cent higher and 8 per cent higher for the energy sector overall. By 2030, the cumulative carbon emissions saved due to the use of nuclear power could exceed 25 billion tonnes. • .

17. 2.4 – Wind power • Itself wind is free and renewable but it alone cannot give power • We need pole, blades,turbine,etc., that is polluting • Also observed change in local wind pattern, and weakening of monsoon locally

18. 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. 18

19. 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. 19

20. 2.6 SOLAR PHOTOVOLTAIC (SPV) TECHNOLOGY -Electricity can be produced directly from sunlight with the help of SPV technology. - SPV technology is based on the photovoltaic effect, which refers to transition of electrons from a lower to a higher energy state having absorbed photons of the right energy. - The photovoltaic effect is like photoelectric effect with a little difference. - While in the photoelectric effect, electrons are ejected from the solid, liquid and gaseous elements when light strikes on the surface of these elements, in the photovoltaic phenomenon the electrons make a transition from a lower to a higher energy state having absorbed photons of the right energy. 20

21. PV….. - The SPV systems consists of two materials in contact with each other. Among them, one is wafer of electron emitting non-metal and other is electron collecting material which pass on electrons in form of electron stream (i.e. current) to circuit. The electron emitting wafer replenishes those electrons which goes out to circuit. This technology involves semiconductors as light absorber, and electronic species (electrons and positively charged holes) as mobile charges moving in device due to mainly drift ( under the influence of electric field) and some diffusion (under the influence of concentration difference). Point is that solar is free and renewable but it byitself not produce electricity. For it, it needs panels, poles, Batteries, etc. whose production and disposal is polluting. 21

22. 2.7. DYE- SENSITIZED SOLAR CELL TECHNOLOGY -Point is that solar is free and renewable but it by itself not produce electricity. For it, it needs dye, electrodes, electrolyte, Batteries, etc. whose production and disposal is polluting. These cells are made up of a porous film of tiny (nanometer sized) white pigment particles made out of titanium dioxide. The titanium dioxide particles are covered with a layer of dye, which is in contact with an electrolyte solution. When solar radiation hits the dye, it injects a negative charge in the pigment nanoparticle and a positive charge into the electrolyte resulting in the conversion of sunlight into electrical energy. 22

23. 2.8.PHOTOGALVANIC CELLS Photogalvanic cells are galvanic cells which have property of solar energy conversion and storage. - This is the very simple technology on which I am working. 23

24. Photogalvanic cells…. -Point is that solar is free and renewable but it by itself not produce electricity. For it, it needs dye, electrodes, electrolyte, Batteries, etc. whose production and disposal is polluting. 24

25. 2.9. Green chemistry – really not green but greenerREACTANT (RAW MATERIAL) → PROCESS → PRODUCT → USE → DISPOSAL- Paul Anastas and John C. Warner developed 12 principles of green chemistry,which help to explain what the definition means in practice. The principles cover such concepts as:* the design of processes to maximize the amount of raw material that ends up in the product;* the use of safe, environment-benign substances, including solvents, whenever possible;the design of energy efficient processes;* the best form of waste disposal: not to create it in the first place. 25

26. The 12 principles of green chemistry are:- It is better to prevent waste than to treat or clean up waste after it is formed.- Synthetic methods should be designed to maximize the incorporation of all materials used in the process into the final product.- Wherever practicable, synthetic methodologies should be designed to use and generate substances that possess little or no toxicity to human health and the environment.- Chemical products should be designed to preserve efficacy of function while reducing toxicity.- The use of auxiliary substances (e.g. solvents, separation agents, etc.) should be made unnecessary wherever possible and innocuous when used.-- Energy requirements should be recognized for their environmental and economic impacts and should be minimized. Synthetic methods should be conducted at ambient temperature and pressure.- A raw material or feedstock should be renewable rather than depleting wherever technically and economically practicable.- Reduce derivatives – Unnecessary derivatization (blocking group, protection/deprotection, temporary modification) should be avoided whenever possible.- Catalytic reagents (as selective as possible) are superior to stoichiometric reagents.- Chemical products should be designed so that at the end of their function they do not persist in the environment and break down into innocuous degradation products.- Analytical methodologies need to be further developed to allow for real-time, in-process monitoring and control prior to the formation of hazardous substances.- Substances and the form of a substance used in a chemical process should be chosen to minimize potential for chemical accidents, including releases, explosions, and fires. 26

27. Green chemistry…..an exampleFamily of polycarbonates very important polymers- made from Bisphenol A & carbonyl chloride( or diphenyl carbonate).Carbonyl chloride is a very poisonous gas, manufactured from other hazardous gases, carbon monoxide and chlorine:On the other hand, diphenyl carbonate is produced from dimethyl carbonate, which is readily manufactured from methanol, carbon monoxide and oxygen in the liquid phase, in presence of copper(II) chloride, CuCl2:Dimethyl carbonate, when heated with phenol in the liquid phase, forms the diphenyl carbonate.Overall, the process for the production of polycarbonate that uses diphenyl carbonate is less hazardous than that using carbonyl chloride.So the point is regarding green chemistry is that it is only relatively cleaner technology not clean. 27

28. 2.10. Other technology -You take any technology,it is unclean. If you make advancement in technology regarding cleaneer aspect, it will be less polluting but not clean at all.- It is because from Ist law of Thermodynamics ,you cannot make anything out of nothing. It means you make something, you need raw material from nature, you need process for production, you use product, you dispose off that, you recycle it.-You do any activity you need energy- fuels- 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. 28

29. ductant. 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 sources(e.g. fossil fuels- coal, petroleum, natural gas) are those energy sources which cannot be renewed after use. Beauty of Non-renewable sources– -Highly developed, highly reliable, high energy density, independent of seasonal & climatic variations, deep penetration in life, modern life owes to them, etc. Thus, if they fail now you can imagine how the life will go haywire.Limitations of Non-renewable sources– polluting, costly, limited in stock, less abundant, geographically unevenly distributed and fastly depleting, so they cannot be safe and lasting source of energy.

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

31. A brief description of some of the significance of CO2 are as - - CO2 and life origin According to current models of the origin of life , the first step towards origin of life was the formation of bio-chemicals like Amino Acids,Phospholipids, RNA, and Proteins .This hypothesis is based on 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 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 chemicals from which life is thought to have formed are - CH4,NH3,H2O,H2S,CO2 or CO and PO43+ . - CO2 and sustaining of life 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 their food (Carbohydrate ) and O2 by the process of photosynthesis. This way CO2 is essential for natural supply of food and O2 for sustaining life.

32. - CO2 and Energy balance of Earth Further, the CO2 as part of green-house gases has important role in Green House Effect(GHE).Importance of GHE is that it traps solar energy on Earth’s surface and atmosphere,and maintains the energy balance on Earth by replenishing energy consumed by plants in photosynthesis.Without GHE, the whole Earth would be converted in to extremely cold planet and consequently life will not be able to have existence.Thus, GHE and in turn CO2 makes Earth inhabitable. - CO2 and Industrial field & Medical field It is also to be noted that CO2 also finds applications in fire-extinguisher,manufacturing of aerated water, refrigeration as dry ice (solid CO2), manufacturing of white lead (Pb) and baking soda, treatment of Pneumonia patients and victims of CO poisoning as carbogen (a mixture of O2 with 5-10 per cent CO2).

33. 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.

34. 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.

35. 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.

36. 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. 36

37. Thanks