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Module - 9. Energy and Environment. There have been some discussions on issues related to energy and environment earlier when we considered extraction of non-ferrous metals. Here we will discuss the subject in some detail. Learning Objectives
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Module - 9 Energy and Environment There have been some discussions on issues related to energy and environment earlier when we considered extraction of non-ferrous metals. Here we will discuss the subject in some detail. • Learning Objectives • To understand the importance of energy and environment related cases in extraction processes • To understand the ‘cost of development’ • To understand the scope of energy reduction in extraction processes • To understand the meaning and significance of the following Waste, pollution, sustainable development, gross ecological product, Life cycle analysis, End use analysis, Subjective horizon, Carbon footprint, Carbon credit etc.
Why are we generating wastes ? Obviously because we are digging into earth’s crust. Earth – Radius 6371 km, of which about half consists of a core, presumably of an alloy of iron and nickel. There is an intermediate layer 2870 km thick which is thought to consist of silicates of magnesium, iron, chromium and also sulphides, tellurides and salenides. The crust of 30 km thick of which the ordinarily accessible portion comprises barely 3 km though boreholes put down for petroleum have reached a depth of 6000 m. When we talk about the abundance of elements forming earth’s crust we talk of only the top 10 km of the crust including the atmosphere and the oceans.
Abundance of elements The twelve most abundant elements account for 99.5 percent by weight of the crust, all other 86 elements together forming one-half of one per cent. Various geochemical factors have made distributions non-uniform.
Lower Limits of workable grade in deposits Percentage of metals from the lower limit of workable grade in deposits * Carbonate Ore
Salient issues in computation of adjusted growth in GDP • Health damage costs due to air pollution are based on population exposure, and morbidity and mortality figures that are attributed to respiratory ailments. • Ecological damage costs due to air pollution includes vegetation loss, loss to ground water recharge, and soil erosion. • Losses due to quantitative decline, and quality degradation due to excessive withdrawal of water and ground water contamination are estimated. • Avoidance costs for surface water contamination from domestic and industrial wastewaters are estimated.
Costs associated with land degradation are productivity losses of land mass under cultivation by assuming aggregate cropping patterns • Loss of forest services / value is estimated based on charges in forest cover with recourse to the guidelines of the Ministry on benefit cost evaluation of projects involving diversion of forest land mass • Biodiversity losses are not included in the estimation of total environmental and ecological losses • Monetized value of natural resources used for growth in GDP not included in calculation.
What is development ? Development is availability of goods and services for all sections of the population. Not necessarily, highways, flyovers, tall buildings, gadgets and consumer items , clubs, disco joints, pubs, swimming pools, shopping malls, automobiles and aeroplanes. Yet these are also important. Progress/Development is demanded by the population. This needs more production, which needs more energy. Progress generally leads to more pollution. All P’s are related. The so called ‘Progress’, if not monitored, well can lead to problems, poverty from unbalanced growth, petty pressure politics , pessimism, prediction of dooms day. Progress with peace and prosperity demands plans, prioritization public participation, people’s power, pragmatism.
Example: Replacing a 75 W incandescent lamp with an 18 W compat fluorescent lamp : yields the same light for a duration nearly 13 times as long, : keeps 1 tonne of CO2 and about 9 kg of SOX from being emitted by coal-fired station. This also generates net wealth because the new lamp saves more in utility bills, replacement lamps, and the labour to install them than it costs. Saving electricity is cheaper than making it and pollution is avoided not at a cost but at a profit. Transport 5 t coal 10t coal Thermal power 25% Eff 1.25 t coal Transmit 25% loss Devices 0.7 t coal equivalent 0.9 t coal 80% Eff
An interesting example ( National Geographic March 2009) • An incandescent bulb ( U S cost 65 cents) lasts 1000-2000 hr costing $ 72.55 in 15 years of electricity. With efficiency of 6% , 94 % of electricity is dissipated as heat. • A CFL bulb with 25% efficiency costs $ 4 a bulb, lasts 6000-12000 hr and in 15 years the electricity bill will be $ 18.14 • The LED lamps being developed operate with 50 per cent efficiency, costs $120 a bulb and lasts 20,000-50000 hr . In 15 years the electricity bill will be $ 9.67 If we have long subjective horizon, we will invest in the last.
EFFECTS ON ENVIRONMENT A. MINING ACTIVITIES • DEPLETION OF NATURAL RESOURCES • DEFORESTATION • DUST AND FINES • SPILLAGE DURING HANDLING & TRANSPORT B. PROCESS • EMISSION OF POISONOUS GASES, FUMES • GENERATION OF DEBRIS, FLY ASH, SLUDGE, SLAG • SPILLAGE OF LUBRICANTS, HAZARDOUS CHEMICALS & WASTES • NOISE, VIBRATION • EVERY ACTIVITY HAS AN EFFECT ON THE ENVIRONMENT
ENVIRONMENTAL POLICY SET OBJECTIVES & TARGET REVIEW OPERATE TO COMPLY WITH LAWS, STATUTES & REGULATIONS REDUCE CONSUMPTION & WASTAGES RECOVER & ERECYCLE MATERIAL WASTES PHASE OUT POLLUTION PRONE PROCESSES AND UPGRADE TECHNOLOGY REHABILITATE WASTE DUMPS DEVELOP AWARENESS AMONG WORKFORCE
PROCEDURES EVALUATION OF ENVIRONMENTAL ASPECTS AND THEIR IMPACT ACCESS TO LEGAL REQUIREMENTS ORGANISATION STRUCTURE WITH RESPONSIBILITY & AUTHORITY TRAINING – NEED & IMPART COMMUNICATION DOCUMENT CONTROL RESPONSE TO ACCIDENTS & EMERGENCY SITUATIONS PROCESS CONTROL CORRECTIVE & PREVENTIVE ACTIONS RECORD KEEPING SYSTEM AUDIT SYSTEM REVIEW
ENVIRONMENTAL ASPECTS EMISSION TO ATMOSPHERE DISCHARGE OF WASTEWATER TO WATER BODIES WASTE MANAGEMENT AND DISPOSAL MANAGEMENT OF HAZARDOUS SUBSTANCES CONTAMINATION OF LAND NOISE, ODOUR, DUST AND VIBRATION USE OF NATURAL RESOURCES, ENERGY LIKELY BREACH OF LEGISLATIVE REQUIREMENTS EMERGENCY SITUATIONS
CRITERIA TO EVALUATE EFFECTS ON ENVIRONMENT TOTAL SCORE = X x Y x Z x F
WASTE MANAGEMENT AVOIDANCE OF WASTES RECYCLING & REUSE OF WASTES MINIMISING ADVERSE IMPACT OF DISPOSAL OF THESE WASTES ON THE ENVIRONMENT
AGENDA OF MANAGEMENT REVIEW LAST MINUTES RESULT OF EMS AUDIT PROGRESS OF ENVIRONMENTAL MANAGEMENT PROGRAMMES PERFORMANCE AGAINST OBJECTIVES & TARGETS RESULTS w.r.t. LEGAL REQUIREMENTS RESOURCE REQUIREMENT TRAINING AND AWARENESS POSSIBLE NEEDS FOR CHANGES ANY OTHER RELEVANT ISSUES
POLLUTION AND THE ALUMINIUM INDUSTRY Local, regional and global effect of emissions Local – release of fluorides cause bronchitis, dental and skeletal fluorisis Regional – CO2, SO2 released can be transported to long distances, washed away by rain and then falling on ground. Reduces growth of vegetation due to acidification of soil. pH of rivers and lakes goes down. Fish cease breeding and eventually leave the area. Aggravates corrosion. Global – Increased CO2 in the air contributes to greenhouse effect and global warming. Air pollutants – C ( shoot), Al2O3 , cryolite, other Al-Na compounds, AlF3, CaF3 Gases – HF, CF4, C2F6, SiF4, SO2, H2S, CS2, COS, CO2, CO, H2O, Hydrocarbons Solid residues – Red mud from Al2O3 plant, flyash from thermal power plants
CO2 emissions from carbonaneous fuels have become a critical subject now. It is increasing at a rate of .028% per year. Carbon emission reduction targets for different countries are as of now the following. The U.S. – 17 per cent of 2005 levels by 2020, 30 per percent by 2030 and 80 per cent by 2050. European Union – 20-30 percent of 2005 levels by 2020. Brazil – 36-38 percent by 2020 South Africa – 15-20 percent by 2020 Indonesia – 26 per cent by 2020 India – No target has been set as yet. Present annual growth rate of carbon emissions – ( In percent) U.S- 25, Canada – 54, Japan – 17, Germany -18, India -97, China – 109 U.K – only 1 and in Russia it is negative ( See National Geographic March 2009)
Two new words that are important today Carbon footprint - Carbon consumption by an individual required to maintain his lifestyle. Carbon Credit – This is acquired by minimizing carbon consumption (1 ton of CO2 saved is on CER) and this can be traded with somebody not doing so in exchange of financial gains. This is one way of rewarding cleaner operation and punishing the polluter. Yet it does not solve the problem.
The U.S is emitting about 6 billion metric tons of CO2 per year which is a fifth of the total world emissions. The main culprit is not the industry. The shares are as follows : • Buildings ( with lighting, heating and appliances) – 38 per cent of the total energy • Transportation – 34 percent of the total energy • Industrial sector ( refineries, paper plants, manufacturing industry) – 28 per cent The metal industry is not that big a culprit – even the steel sector is responsible for only 4-6 percent of the global CO2 emission. Yet we cannot be complacent. The commercial aviation sector releases 2% of total CO2 , that too high above earth (more damaging) but it is committed to keep it at that level. The subject of CO2 sequestration is very important but we will not discuss it here.