Air pollution in petroleum industryPresentation Transcript
Air Pollution in Petroleum Industry
Sources of Air Pollution in Oil Field
Classification of Pollutants
Types of Pollutants
Harmful Effects of Air Pollution
Precautionary Measures to Check Air Pollution
Introduction: The exploration & exploitation activities of petroleum industry often causes environmental degradation that have significant impact on quality of air, water, soil, vegetation and on health unless adequate preventive measures are planned.
Introduction (Cont…..) It is also true that we cannot get absolutely pure air. All our developmental activities that are concentrated towards utilization of HC resources or improving the quality of life, lead to various environmental problems and air pollution is one of the most important area concern. However , it is possible for us to minimize the impact of such developmental activities on quality of air if, only, we are aware of the hazards and phenomena involved in air pollution apart statutory significance.
Introduction (Cont…..) Environment: “ The objects or the region surrounding anything”. “It is the sum total of influences which modify and determine the development of life and character.”
Introduction (Cont…..) Environmental Pollution: It may be defined as “ the introduction by man into the environment by substances or energy liable to cause hazards to human health, harm to living resources & ecological systems, damage to structures or interference with legitimate uses of the environment.
Introduction (Cont…..) Air Pollution: “ The presence of one or more contaminants such as dust fumes, gas, mist, odor, smoke or vapour in such quantities that are injurious to human, plant or animal life or to property.
Introduction (Cont…..) Requisites for Air Pollution: There are 3 basic requisites to enter any air pollution problem :
There must be an emission.
After emission it must be confined to a restricted volume of air.
The polluted air must interfere with the physical, mental and social. well being of people
SOURCES OF AIR POLLUTION IN OIL FIELD: The various sources of air contamination which are encountered in oil fields are : The exhaust of derrick engines and generators, pump engines, compressors etc. 2. Pungent fumes, odours and dust from cementing units and from mud banks. 3. Evaporation of crude oil from oil pits in the form of vapours during production testing .
SOURCES OF AIR POLLUTION IN OIL FIELD (Cont……) : 4. Discharge of natural gas directly to the atmosphere during production testing. 5. Burning of the oil from effluent pit. 6. Flaring of natural gas to the atmosphere. 7. Burning of gas and effluent water from the flare pit in the air directly from various oil terminals. 8. Presence of smoke , Fog, Mist & wind in which S.P.M. remains suspended near the earth surface.
SOURCES OF AIR POLLUTION IN OIL FIELD (Cont……) : 9. Oxidation of various pollutants . 10. Depletion of the natural resources & decrease in forest areas disturbing the eco system. 11. The weather & orography of oil fields. 12. Discharge of associated low pressure natural gas to the atmosphere. Increase in surrounding temp. due to flare. Glare effect of flare which adversely effect the nearby vegetation.
Classification of Pollutants: Pollutants or contaminants generated due to various operational & developmental activities may be classified as: 1. Primary Pollutants : These are emitted on a consequence of a process. These exist in air in the same form as it was discharged. E.g. the exhaust of oxides of nitrogen from a car. 2. Secondary Pollutants: They are formed as products of some reactions, generally, the existing pollutants react with some other some substance in the atmosphere. e.g. smog formed when oxides of nitrogen combine with HCs in the presence of sunlight
Primary Pollutants : This can be categorized: PARTICULATE POLLUTANTS ----- Fine particles suspended in air or gas and (B) GASEOUS POLLUTANTS ----- such as sulphur, nitrogen, carbon and halogen containing compounds.
PARTICULATE POLLUTANTS: This refers to fine particles that are more than 0.01 micron in size. These can be fine droplets of liquids as in fogs and mists or solid particles like soot or those suspended in smoke. Particulate Pollutant Category
Particulate Pollutant Category
Particulate Pollutant Category The sources of these Particulate pollutants include: Natural Sources: Winds, Drought, Storm, Forest Fires etc. Industrial /Anthropogenic sources: Industries, Incineration, Vehicle exhausts etc. Household Sources Agricultural Sources
(B) GASEOUS POLLUTANTS: Gaseous pollutants such as SOx, Nox, mercury or organic vapour are miscible with air in all proportions. They are generated during combustion and other industrial process.
SECODARY POLLUTANTS: As a result of chemical reactions between volatile organic compounds ( emitted from vehicles, industries) and oxides of nitrogen ( generated through transportation & industrial sources), a principal component of smog is formed. e.g. 1. Oxidation of NO to NO2 2. Oxidation of Hydrocarbon 3. Formation of Ozone
On shore Air Pollution : The main sources of continuous or non – continuous air emissions resulting from onshore activities include:
Combustion sources from power & heat generation.
Use of compressors, pumps & engines ( boilers, turbines etc.)
Flaring & Venting of HCs.
On shore Air Pollution (Cont…….): The principal pollutants from these air emission sources : Nitrogen Oxides Sulfur Oxides Carbon monoxide & Particulate Additional Pollutants------ --- Hydrogen Sulfide --- Volatile Organic Compounds. --- Benzene(C6H6) --- Toluene(C6H8), Xylenes (C8H10) etc.
On shore Air Pollution (Cont…….): Air quality impacts are estimated by comparing with baseline air quality which ensures that no adverse impacts to human health & the environment.
On shore Air Pollution (Cont…….): Exhaust Gases: The most significant sources of exhaust gas emissions from onshore facilities :
Combustion of gas or liquid fuels in turbines, boilers, compressors, pumps & other engines for power and heat generation.
On shore Air Pollution (Cont…….): 2. Venting & Flaring: Associated gas brought to the surface with crude oil during oil production is sometimes disposed off at onshore facilities by venting or flaring to the atmosphere. This practice is now widely recognized to be a waste of a valuable resource, as well as a significant source of GHG emissions. However , flaring or venting are also important safety measures used on onshore oil & gas facilities to ensure gas and other HCs are safely disposed in the event of an emergency, power or equipment failure etc.
On shore Air Pollution (Cont…….): Continuous venting of associated gas is not considered a good practice and should be avoided. The associated gas stream should be routed to an efficient flare system, although continuous flaring of gas should be avoided if feasible alternatives are available. Before flaring is adopted, feasible alternatives for the use of gas should be evaluated to the maximum extent possible and integrated into production design.
On shore Air Pollution (Cont…….): What are those alternative options? Alternative options may include: Gas utilization for on- site energy needs Export of the gas to a neighboring facility or to the market Gas injection for reservoir pressure maintenance. Enhanced recovery using gas lift. if none of these alternatives is feasible, continuous improvement in flaring technology should be implemented.
On shore Air Pollution (Cont…….): 3. Fugitive Emissions: Fugitive emissions at onshore facility may be associated with vents, leaking pipes & tubings, valves, connections, pump seals, compressor seals, pressure relief valves, tanks or open pits and HC loading & unloading operations.
On shore Air Pollution (Cont…….) To control fugitive emissions: good design and maintenance of facility is must. The selection of valves, fittings, seals etc should be maintained for the same. Leak detection facility should be there. Vapour control units should be installed for HC loading and unloading operations. Use of open vents in tank roofs should be avoided by installing pressure relief valves.
Off shore Air Pollution
The main sources of air emissions resulting from offshore activities include: Combustion sources from power and heat generation Use of Compressors, pumps, boilers, turbines etc. Flaring & venting of HCs. Fugitive emissions.
The principal pollutants from these air emission sources : Nitrogen Oxides Sulfur Oxides Carbon monoxide, CO2 & Particulate Additional Pollutants------ --- Hydrogen Sulfide --- Volatile Organic Compounds. --- methane & ethane --- Benzene --- Toluene, Xylenes etc.
Off shore Air Pollution (Cont…….): Exhaust Gases: Exhaust gas emissions produced by Combustion of gas or liquid fuels in turbines, boilers, compressors, pumps & other engines for power and heat generation can be the most significant sources of exhaust gas emissions from offshore facilities.
Off shore Air Pollution (Cont…….): 2. Venting & Flaring: Associated gas brought to the surface with crude oil during oil production is sometimes disposed off at onshore facilities by venting or flaring to the atmosphere. This practice is now widely recognized to be a waste of a valuable resource, as well as a significant source of GHG emissions. All efforts should be made to keep flaring to the minimum and only for technical reasons and safety. Flares are also a problem in terms of aesthetics.
Off shore Air Pollution (Cont…….): 3. Fugitive Emissions: Fugitive emissions at offshore facility may be associated with vents, leaking pipes & turbines, valves, connections, pump seals, compressor seals, pressure relief valves, tanks or open pits and HC loading & unloading operations.
Air Quality Standards: They are the standards that specify allowable emission. It can either be related to : Quality of the air in the surrounding atmosphere (ambient air quality) – Useful for the protection of the health of living populations, animals and of property. Gaseous emissions from a particular unit ( emission standard) --- used for planning pollution control strategy.
Ambient Air Quality Standards: In India, for AAQS, various areas have been classified into 3 categories: Category A: covers Industrial and mixed – use areas. Category B: Covers residential and Rural areas. Category C: Covers sensitive areas such as sanctuaries, national parks, hill stations etc.
Ambient Air Quality Standards: India
Indian Emission Standards ( Abstracted)
Harmful Effects of Air Pollution: Polluted air can cause: sickness or death that lead to human & economic losses. Reduce visibility Cause unpleasant odors ( like from sulfur compounds). 4. Can damage agricultural crops, plants, livestock ( Fluorine and arsenic settle on or react with animal fodder). Consuming such fodder result into loss of strength, weight and death.
Harmful Effects of Air Pollution: e.g. Although SO2 has a disagreeable odour above about 0.5 ppm, its immediate effects on most people are negligible below a few ppm. However, a one hour exposure to 5ppm causes choking, and one hour at 10ppm produces great distress. A few sensitive individuals have experienced severe bronchospasm at even 1 to 2 ppm. Sulphur dioxide when released in the atmosphere can also convert to SO3, which leads to production of sulphuric acid. When SO3 is inhaled it is likely to be absorbed in moist passages of respiratory tract and it may reach to deeper into lungs.
Harmful Effects of Air Pollution: The toxicity of Nitrogen dioxide is considerably less than that of Sulphurdi oxide. Most people first notice eye and nasal irritation at about 13 ppm. Almost all NOx emissions are in the form of NO, which has no, known adverse health effects in the concentrations found in the atmosphere, which in turn may give rise to secondary pollutants, which are injurious. NO2 may also lead to formation of HNO3, which is washed out of the atmosphere as acid rain.
Harmful Effects of Air Pollution: Most of the CO emissions are from transportation sector. Peek concentrations occur at street level in busy urban centers particularly when there is no atmospheric mixing as it happens during winter season. Carbon monoxide is not an odorous or irritating gas, but, combines with the hemoglobin of the blood and reduces its oxygen carrying capacity. Most people experience dizziness, headache, lassitude etc. after 1 or 2 hrs. exposure to 100 ppm of CO.
Harmful Effects of Air Pollution: Lead released from motor vehicle exhaust may affect human populations by direct inhalations , in which case people living nearest to highways are at greatest risk. Lead can be ingested also after it is deposited on the foodstuffs. it may cause behavioral changes, learning disabilities and permanent brain damage.
Precautionary Measures to check Air Pollution Problems 1. By Using Absorbers 2. Application of Vapour Recovery System 3. Standardization of the height of the flare stacks. 4. By introduction of diluters 5. Air regulation control during the combustion of natural gas 6. Pre burning treatment to the various effluents before discharging to atmosphere. 7. Replacement of the damages of greenery near installations, work centers etc. 8. Control of flare light by virtue of which majority of birds & insects have been migrated. 9. Good design of equipments.
THERMAL POWER PLANTS: Thermal power plants are major sources of SPM, SO2 and Nox depending upon the type of Fuel used. Emission of one or more of these pollutants may be of environmental significance.
A large amount of SPM as fly ash is emitted from coal fired power plants, particularly if the ash removal unit such as an electrostatic or precipitation (ESP ) is not used.
AUTOMOBILES: In urban areas automobiles form a significant source of a number of air pollutants namely particulates, hydrocarbon and lead. Non- uniform oxygen supply within the combustion chamber and lower flame temperature leads to incomplete combustion releasing CO, HC and unburnt particles in the exhaust.