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CONTROLLING AUTOMOBILE POLLUTION IN A UNIQUE WAY
CONTROLLING AUTOMOBILE POLLUTION IN A UNIQUE WAY
POLLUCAREAUTO EMISSION IMPROVERIMPROOVING AUTOMOBILE EMISSIONS (BIO SOLUTION)
IntroductionVehicle emissions control is the study and practice of reducing the motor vehicle emissions -- emissions produced by motor vehicles, especially internal combustion engines.
Emissions of many air pollutants have been shown to have variety of negative effects on public health and the natural environment. Emissions that are principal pollutants of concern include:
* Hydrocarbons - A class of burned or partially burned fuel, hydrocarbons are toxins. Hydrocarbons are a major contributor to smog, which can be a major problem in urban areas. Prolonged exposure to hydrocarbons contributes to asthma, liver disease, , lung disease, and cancer. Regulations governing hydrocarbons vary according to type of engine and jurisdiction; in some cases, "non-methane hydrocarbons" are regulated, while in other cases, "total hydrocarbons" are regulated. Technology for one application (to meet a non-methane hydrocarbon standard) may not be suitable for use in an application that has to meet a total hydrocarbon standard. Methane is not directly toxic, but is more difficult to break down in a catalytic converter, so in effect a "non-methane hydrocarbon" regulation can be considered easier to meet. Since methane is a greenhouse gas, interest is rising in how to eliminate emissions of it.
* Carbon monoxide (CO) - A product of incomplete combustion, carbon monoxide reduces the blood's ability to carry oxygen; overexposure (carbon monoxide poisoning) may be fatal. Carbon Monoxide poisoning is a major killer.
* Nitrogen oxides (NOx) - Generated when nitrogen in the air reacts with oxygen at the high temperature and pressure inside the engine. NOx is a precursor to smog and acid rain. NOx is a mixture of NO, N2O, and NO2. NO2 is extremely reactive. It destroys resistance to respiratory infection. NOx production is increased when an engine runs at its most efficient (i.e. hottest) part of the cycle.NOx, a major air pollutant causes asthma and respiratory and heart diseases.
* Particulate matter – Soot or smoke made up of particles in the micrometre size range: Particulate matter causes negative health effects, including but not limited to respiratory disease and cancer.
* Sulfur oxide (SOx) - A general term for oxides of sulfur, which are emitted from motor vehicles burning fuel containing sulfur. Reducing the level of fuel sulfur reduces the level of Sulfur oxide emitted from the tailpipe. Refineries generally fight requirements to do this because of the increased costs to them, ignoring the increased costs to society as a whole.
* Volatile organic compounds (VOCs) - Organic compounds which typically have a boiling point less than or equal to 250 °C; for example chlorofluorocarbons (CFCs) and formaldehyde. Volatile organic compounds are a subsection of Hydrocarbons that are mentioned separately because of their dangers to public health.The impact of internal combustion engines on the environment and our lifestyles has been considerable.
There is a tremendous increase in the Number, Power, Speed and Size of the Vehicles.Several of the compounds present in diesel and gasoline engine exhausts are known to be carcinogenic and/or mutagenic .
It is high time to concentrate on simpler control methods on exhaust emissions so as to reduce the impact of these emissions on health and the environment.
How stringent are emission regulation acts
Indian Emission Standards (4-Wheel Vehicles)Standard Reference Date Region India 2000 Euro 1 2000 Nationwide Bharat Stage II Euro 2 2001 NCR*, Mumbai, Kolkata, Chennai 2003.04 NCR*, 12 Cities† 2005.04 Nationwide Bharat Stage III Euro 3 2005.04 NCR*, 12 Cities† 2010.04 Nationwide Bharat Stage IV Euro 4 2010.04 NCR*, 12 Cities†
* National Capital Region (Delhi) † Mumbai, Kolkata, Chennai, Bengaluru, Hyderabad, Ahmedabad, Pune, Surat, Kanpur, Lucknow, Sholapur, and Agra
Emission Standards for Light-Duty Diesel Vehicles, g/kmYear Reference CO HC HC+NOx PM1992 - 17.3-32.6 2.7-3.7 - -1996 - 5.0-9.0 - 2.0-4.0 -2000 Euro 1 2.72-6.90 - 0.97-1.70 0.14-0.252005† Euro 2 1.0-1.5 - 0.7-1.2 0.08-0.
The California Air Resources Board proposed a new regulation to control emissions of greenhouse gases (GHG) from light-duty vehicles, which calls for a 30% GHG emission reduction phased-in from 2009 to 2014. The proposal has been developed under the California bill AB 1493, adopted in 2002, which requires the ARB to develop and adopt, by January 1, 2005, regulations that achieve the “maximum feasible reduction of greenhouse gases emitted by passenger vehicles and light-duty trucks”. It is the first legislation in US history to regulate carbon dioxide and other greenhouse gas emissions from cars and light-duty trucks.
The proposal covers vehicle climate change emissions comprised of four main components: (1) carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O, not to be confused with the regulated NOx emissions, which include NO and NO2) emissions resulting directly from operation of the vehicle, (2) CO2 emissions resulting from operating the air conditioning system (indirect AC emissions), (3) refrigerant emissions from the air conditioning system due to either leakage, losses during recharging, or release from scrappage of the vehicle at end of life (direct AC emissions), and (4) upstream emissions associated with the production of the fuel used by the vehicle.
The climate change emission standard proposal introduces CO2-equivalent emission standards (where the other GHG emissions are converted to CO2 based on their climate warming potential), which are incorporated into the current California LEV program. Accordingly, there
would be a CO2 equivalent fleet average emission requirement for the passenger car/light-duty truck 1 (PC/LDT1) category and another for the light-duty truck 2 (LDT2) category, just as there are fleet average emission requirements for criteria pollutants for both these categories.
The ARB considers the following groups of technologies for meeting of the CO2 emission standards:
1. Engine, Drivetrain, and Other Vehicle Modifications—valvetrain, transmission, vehicle accessory, hybrid-electric, and overall vehicle modifications designed to reduce engine exhaust CO2 emissions from conventional vehicles
2. Mobile Air-Conditioning System—air conditioning unit modifications to reduce vehicle CO2 emissions and refrigerant modifications to reduce emissions of HFC refrigerants, such as HFC-134a
3. Alternative Fuel Vehicles—the use of vehicles that use fuels other than gasoline and diesel to reduce the sum of exhaust emissions and “upstream” fuel delivery emissions of climate change gases
4. Exhaust Catalyst Improvement—exhaust aftertreatment alternatives to reduce tailpipe emissions of CH4 and N2O (the latter gas being a common by-product generated in three-way catalytic converters)
5. High speed direct injection diesel engines are named as a technology that can provide significant CO2 reductions when compared to conventional gasoline engines. Other engine and drivertrain technologies analyzed by the ARB include valvetrain and charge modifications, variable compression ratio, gasoline direct injection, homogeneous charge compression ignition, and more.
6. The regulation is expected to be challenged in court by the automotive industry and, possibly, by the federal government. The manufacturers will likely argue that CO2 emission regulation is in fact a disguised form of more stringent fuel economy standards, which are outside California jurisdiction. On the other hand, the California move will trigger similar actions by other states, many of which are disappointed with the indifference about climate change by the federal government.Source: California ARB
A mobile emission reduction credit (MERC) is an emission reduction credit generated within the transportation sector. The term “mobile sources” refers to motor vehicles, engines, and equipment that move, or can be moved, from place to place.[1] Mobile sources include vehicles that operate on roads and highways ("on-road" or "highway" vehicles), as well as nonroad vehicles, engines, and equipment. Examples of mobile sources are passenger cars, light trucks, large trucks, buses, motorcycles, earth-moving equipment, nonroad recreational vehicles (such as dirt bikes and snowmobiles), farm and construction equipment, cranes, lawn and garden power tools, marine engines, ships, railroad locomotives, and airplanes. In California, mobile sources account for about 60 percent of all ozone forming emissions and for over 90 percent of all carbon monoxide (CO) emissions from all sources.
1. Benzene2. Bromdioxins 3. Bromfurans 4. Carbon Dioxide (CO2) 5. Carbon Monoxide [CO] 6. Ethenol7. Hydrocarbon [HC] 8. Methane (CH4) 9. Methanol10. Nitrous Oxide (N2O) 11. NO 12. NO2 13. Organic Halides.14. Particulates15. Polychlorinated Dibenzodioxins (PCDD) 16. Polychlorinated Dibenzofurans (PCDF) 17. Polycyclic Aromatic Compounds 18. Residues Of Ethylene Dibromide19. Residues Of Ethylene Dichloride 20. Toluene21. Unregulated Pollutants,
A catalytic converter (colloquially, "cat" or "catcon") is a device used to convert toxic exhaust emissions from an internal combustion engine into non-toxic substances. Inside a catalytic converter, a catalyst stimulates a chemical reaction in which noxious byproducts of combustion are converted to less toxic substances by dint of catalysed chemical reactions. The specific reactions vary with the type of catalyst installed. Most present-day vehicles that run on gasoline are fitted with a "three way" converter, so named because it converts the three main pollutants in automobile exhaust: an oxidising reaction converts carbon monoxide(CO) and unburned hydrocarbons(HC), and a reduction reaction converts oxides of nitrogen (NOx) to produce carbon dioxide(CO2), nitrogen(N2), and water(H2O).
The first widespread introduction of catalytic converters was in the United States market, where 1975 model year automobiles were so equipped to comply with tightening U.S. Environmental Protection Agency regulations on automobile exhaust emissions. The catalytic converters fitted were two-way models, combining carbon monoxide(CO) and unburned hydrocarbons(HC) to produce carbon dioxide(CO2) and water(H2O). Two-way catalytic converters of this type are now considered obsolete except on lean burn engines.[citation needed] Since most vehicles at the time used carburetors that provided a relatively rich air-fuel ratio, oxygen (O2) levels in the exhaust stream were in general insufficient for the catalytic reaction to occur. Therefore, most such engines were also equipped with secondary air injection systems to induct air into the exhaust stream to allow the catalyst to function.
Catalytic converters are still most commonly used on automobile exhaust systems, but are also used on generator sets, forklifts, mining equipment, trucks, buses, locomotives, airplanes and other engine fitted devices. This is usually in response to government regulation, either through direct environmental regulation or through Health and Safety regulations.
The catalytic converter consists of several components:1. The catalyst core, or substrate. For automotive catalytic converters, the core is usually a ceramic
monolith with a honeycomb structure. Metallic foil monoliths made of FeCrAl are used in some applications. This is partially a cost issue. Ceramic cores are inexpensive when manufactured in large quantities. Metallic cores are less expensive to build in small production runs. Either material is designed to provide a high surface area to support the catalyst washcoat, and therefore is often called a "catalyst support". The cordierite ceramic substrate used in most
catalytic converters was invented by Rodney Bagley, Irwin Lachman and Ronald Lewis at Corning Glass, for which they were inducted into the National Inventors Hall of Fame in 2002.
2. The washcoat. A washcoat is a carrier for the catalytic materials and is used to disperse the materials over a high surface area. Aluminum oxide, Titanium dioxide, Silicon dioxide, or a mixture of silica and alumina can be used. The catalytic materials are suspended in the washcoat prior to applying to the core. Washcoat materials are selected to form a rough, irregular surface, which greatly increases the surface area compared to the smooth surface of the bare substrate. This maximizes the catalytically active surface available to react with the engine exhaust.
3. The catalyst itself is most often a precious metal. Platinum is the most active catalyst and is widely used, but is not suitable for all applications because of unwanted additional reactions[vague] and high cost. Palladium and rhodium are two other precious metals used. Rhodium is used as a reduction catalyst, palladium is used as an oxidation catalysts, and platinum is used both for reduction and oxidation. Cerium, iron, manganese and nickel are also used, although each has its own limitations. Nickel is not legal for use in the European Union (because of its reaction with carbon monoxide into nickel tetracarbonyl). Copper can be used everywhere except North America, where its use is illegal because of the formation of dioxin.For compression-ignition (i.e., diesel engines), the most-commonly-used catalytic converter is the Diesel Oxidation Catalyst (DOC). This catalyst uses O2 (oxygen) in the exhaust gas stream to convert CO (carbon monoxide) to CO2 (carbon dioxide) and HC (hydrocarbons) to H2O (water) and CO2. These converters often operate at 90 percent efficiency, virtually eliminating diesel odor and helping to reduce visible particulates (soot). These catalyst are not active for NOx reduction because any reductant present would react first with the high concentration of O2 in diesel exhaust gas.
Reduction in NOx emissions from compression-ignition engine has previously been addressed by the addition of exhaust gas to incoming air charge, known as exhaust gas recirculation (EGR). In 2010, most light-duty diesel manufactures in the U.S. added catalytic systems to their vehicles to meet new federal emissions requirements. There are two techniques that have been
developed for the catalytic reduction of NOx emissions under lean exhaust condition - selective catalytic reduction (SCR) and the lean NOx trap or NOx adsorber. Instead of precious metal-containing NOx adsorbers, most manufacturers selected base-metal SCR systems that use a reagent such as ammonia to reduce the NOx into nitrogen. Ammonia is supplied to the catalyst system by the injection of urea into the exhaust, which then undergoes thermal decomposition and hydrolysis into ammonia. One trademark product of urea solution, also referred to as Diesel Emission Fluid (DEF), is AdBlue.Diesel exhaust contains relatively high levels of particulate matter (soot), consisting in large part of elemental carbon. Catalytic converters cannot clean up elemental carbon, though they do remove up to 90 percent of the soluble organic fraction, so particulates are cleaned up by a soot trap or diesel particulate filter (DPF). A DPF consists of a Cordierite or Silicon Carbide substrate with a geometry that forces the exhaust flow through the substrate walls, leaving behind trapped soot particles. As the amount of soot trapped on the DPF increases, so does the back pressure in the exhaust system. Periodic regenerations (high temperature excursions) are required to initiate combustion of the trapped soot and thereby reducing the exhaust back pressure. The amount of soot loaded on the DPF prior to regeneration may also be limited to prevent extreme exotherms from damaging the trap during regeneration. In the U.S., all on-road light, medium and heavy-duty vehicles powered by diesel and built after January 1, 2007, must meet diesel particulate emission limits that means they effectively have to be equipped with a 2-Way catalytic converter and a diesel particulate filter. Note that this applies only to the diesel engine used in the vehicle. As long as the engine was manufactured before January 1, 2007, the vehicle is not required to have the DPF system. This led to an inventory runup by engine manufacturers in late 2006 so they could continue selling pre-DPF vehicles well into 2007.
Most of the pollution put out by a car occurs during the first five minutes before the catalytic converter has warmed up sufficiently.
In 1999, BMW introduced the Electric Catalytic Convert, or "E-CAT", in their flagship E38 750iL sedan. Coils inside the catalytic converter assemblies are heated electrically just after engine start, bringing the catalyst up to operating temperature much faster than traditional catalytic converters can, providing cleaner cold starts and low emission vehicle (LEV) compliance.
PCV VALVE
purpose of the positive crankcase ventilation (PCV) system, is to take the vapors produced in the crankcase during the normal combustion process, and redirecting them into the air/fuel intake system to be burned during combustion. These vapors dilute the air/fuel mixture so they have to be carefully controlled and metered in order to not affect the performance of the engine. This is the job of the positive crankcase ventilation (PCV) valve. At idle, when the air/fuel mixture is very critical, just a little of the vapors are allowed in to the intake system. At high speed when the mixture is less critical and the pressures in the engine are greater, more of the vapors are allowed in to the intake system. When the valve or the system is clogged, vapors will back up into the air filter housing or at worst, the excess pressure will push past seals and create engine oil leaks. If the wrong valve is used or the system has air leaks, the engine will idle rough, or at worst, engine oil will be sucked out of the engine.
The purpose of the exhaust gas recirculation valve (EGR) valve is to meter a small amount of exhaust gas into the intake system, this dilutes the air/fuel mixture so as to lower the combustion chamber temperature. Excessive combustion chamber temperature creates oxides of nitrogen, which is a major pollutant. While the EGR valve is the most effective method of controlling oxides of nitrogen, in it's very design it adversely affects engine performance. The engine was not designed to run on exhaust gas. For this reason the amount of exhaust entering the intake system has to be carefully monitored and controlled. This is accomplished through a
series of electrical and vacuum switches and the vehicle computer. Since EGR action reduces performance by diluting the air /fuel mixture, the system does not allow EGR action when the engine is cold or when the engine needs full power.
EVAPORATIVE CONTROLSGasoline evaporates quite easily. In the past, these evaporative emissions were vented into the atmosphere. 20% of all HC emissions from the automobile are from the gas tank. In 1970 legislation was passed, prohibiting venting of gas tank fumes into the atmosphere. An evaporative control system was developed to eliminate this source of pollution. The function of the fuel evaporative control system is to trap and store evaporative emissions from the gas tank and carburetor. A charcoal canister is used to trap the fuel vapors. The fuel vapors adhere to the charcoal, until the engine is started, and engine vacuum can be used to draw the vapors into the engine, so that they can be burned along with the fuel/air mixture. This system requires the use of a sealed gas tank filler cap. This cap is so important to the operation of the system, that a test of the cap is now being integrated into many state emission inspection programs. Pre-1970 cars released fuel vapors into the atmosphere through the use of a vented gas cap. Today with the use of sealed caps, redesigned gas tanks are used. The tank has to have the space for the vapors to collect so that they can then be vented to the charcoal canister. A purge valve is used to control the vapor flow into the engine. The purge valve is operated by engine vacuum. One common problem with this system is that the purge valve goes bad and engine vacuum draws fuel directly into the intake system. This enriches the fuel mixture and will foul the spark plugs. Most charcoal canisters have a filter that should be replaced periodically. This system should be checked when fuel mileage drops.
LeadSplashing and/or washing plant shoots with aqueous solutions of the chelates Ca EDTA (max. 0·5%) or Na-polyphosphate (max. 0·5%) is an effective way to reduce contamination and uptake of lead by plants in areas where emission of airborne lead occurs. If the decomposition of chelates in the rhizosphere is prevented, they are also effective in reducing lead uptake by the plant roots.(K. Isermann; A method to reduce contamination and uptake of lead by plants from car exhaust gases; Environmental Pollution (1970); Volume 12, Issue 3, March 1977, Pages 199-203)
CatalystsMetal-enriched zeolites are known to effectively catalyze nitrous oxide in automobile exhaust. Most of these catalysts, however, break down in the presence of water, which can compose 5% to 10% of the exhaust gas. A reproducible method for producing iron-rich ZSM-5 zeolites that do not break down in the presence ofwater was developed.
Rubrivivax gelatinosus (Syn: Methylibium petroleiphilum)Upon feeding CO to the gas phase of a photosynthetic bacterium Rubrivivax gelatinosus CBS, a CO oxidation: H2 production pathway is quickly induced. Hydrogen is produced according to the equation CO + H2O → CO2 + H2. Two enzymes are known to be involved in this pathway: a CO dehydrogenase (CODH) with a pH optimum of 8.0 and above, and a hydrogenase with a pH optimum near 7.5. Carbon monoxide dehydrogenase also displays a temperature optimum near 50°C. When CO mass transfer is not limited during a CO uptake measurement, an extreme fast rate of CO uptake was determined, allowing for the removal of near 87% of the dissolved CO from a bacterial suspension within 10 s. This process has therefore two potential applications,
one in the production of H2 gas as a clean renewable fuel using the linked CO oxidation: H2 production pathway, and another in using the CODH enzyme itself as a fuel-gas conditioning catalyst. These applications thereby will improve the overall H2 economy when gasified waste biomass serves as the inexpensive feedstock.
Treatment of the exhaust to improve tailpipe emissions 1. By using beneficial microbes which will consume/ degrade the Benzene, CO2, CO, HC,
CH4, N2O, NO, NO2, Toluene etc.2. By using natural Gas Adsorbants which bind the emissions3. By using Oxygen Liberators which improve Oxygen. 4. By Using 32.5% Nitrogen solution which can remove enough NOx from auto exhaust to
comply with even stringent statutory limits
Pollucare cleans the exhaust after combustion. A portion of the Pollucare is held in a separate storage tank and injected as a fine mist into the hot exhaust gases. The heat breaks the Nitrogen solution down into ammonia—the actual NOx-reducing agent. Through a catalytic converter, the ammonia breaks the NOx down to harmless nitrogen
(N) gas and water vapor. The exhaust is no longer a pollutant; the atmosphere is about 80% nitrogen gas.
Also the Oxygen liberators provide oxygen which is essential for the microbes and the oxygen left over after the consumption by the microbes comes with the final out flow of the treated emissions
The Gas adsorbants bind the obnoxious gases.
The microbes degrade CO2 and CO into Carbon and Oxygen. A part of the Carbon is consumed by them. They also breakother pollutants.
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