Similar to the oxidation converter, the reduction catalytic converter helps eliminate hydrocarbons and carbon- monoxide emissions, plus oxides of nitrogen emissions, or NOx. NOx emissions are produced in the engine combustion chamber when it reaches extremely high temperatures more than 2,500 degrees Fahrenheit, approximately.
Why do we need continuously improved exhaust after treatment systems?
An aftertreatment system is a method or device for reducing harmful exhaust emissions from internal-combustion engines. In other words, it is a device that cleans exhaust gases to ensure the engines meet emission regulations. 1 - Engine. 2 - ECM.
How dangerous is carbon monoxide in engine exhaust?
Apr 16, 2013 · These designs were essentially two-way oxidation catalysts, so called because they reduce tailpipe emissions of both carbon monoxide and hydrocarbons by oxidizing them to carbon dioxide and water. This type is known as a two-way catalytic converter, because it can only operate with hydrocarbons (unburned fuel) and carbon monoxide (caused by partially- …
How can I reduce the amount of carbon monoxide in my home?
Dec 08, 2017 · Diesel Oxidation Catalyst (DOC) – The DOC reduces particulate matter and oxidizes carbon monoxide and hydrocarbons. DPF – This filter is designed to remove more than 90 percent of particulates out of the exhaust, according …
Can you fix your car’s exhaust emissions with a chemical?
After-treatment systems such as EGR and SCR are widely accepted as the prime route for early Euro VI compliant applications. However, while these are proven paths to reducing NOx emissions, there are trade-offs associated with each approach. EGR limits combustion temperature by introducing cooled exhaust gas into the intake system, reducing NOx.
How can we reduce engine exhaust gases toxicity?
How after treatment system helps in controlling NOx?
Which is the most effective after treatment for reducing engine emissions?
What is the after treatment?
: a secondary treatment to which a material (as film or dyed goods) is subjected after the primary treatment is finished.
Which exhaust gas emission does a NOx adsorber catalyst attempt to reduce?
How do diesel engines reduce NOx emissions?
What part of engine is responsible to prevent loss of gases?
What are the major emissions that come out of engine exhaust?
What is the major difference between BS4 and BS6 norms?
How does after treatment system work?
What is after treatment control module?
How does a DPF regenerate?
Active regeneration happens when extra fuel is injected automatically as the filter reaches an approximately 45% full limit. The extra fuel raises the temperature of the exhaust and burns off the stored soot. Yet the journey has to be long enough to complete a full cycle.Nov 13, 2019
Does exhaust throttling reduce air-fuel ratio?
Intake or exhaust throttling may reduce air–fuel ratio and increase the exhaust temperature for the aftertreatment system (e.g., DPF regeneration, SCR, LNT). Exhaust throttling generally produces less BSFC penalty than the pre-compressor intake throttling. However, any throttle valves placed in any part of the engine air system increase BSFC significantly, and their use should be avoided or minimized in engine system design. Although all the air control valves can achieve a wide range of controls of exhaust temperature and space velocity by adjusting the air flow rate, only VVA (e.g., early or late IVC, or cylinder deactivation) can achieve them without BSFC penalty. Early EVO and the valve events to obtain internal EGR may also increase the exhaust temperature. The benefit of exhaust temperature increase by VVA is especially important at light loads and during warm-up.
What is selective catalytic reduction?
Selective Catalytic Reduction (SCR) is another method, in addition to EGR, to reduce the level of NOx emissions. Rather than engine-out, SCR reduces tailpipe NOx emissions. In the presence of a catalyst, urea turns into ammonia and carbon dioxide, which then reacts with the NOx to create nitrogen and water vapour.
Is biodiesel a fuel injection system?
In addition, the introduction of bio-diesels is a cause of concern for fuel injection systems. The first generation of bio-diesels based on the esterisation of plant oils are subject to oxidation and deterioration with time.
What is CAE in automotive?
CAE (computer assisted engineering) has become a popular tool for development of both the automotive catalyst and the total after-treatment system . This paper reports on using the CAE approach for modeling the DOC (diesel oxidation catalyst) + CSF (catalyzed soot filter) system. Two cases of modeling are shown here. One case is a modeling of DOC pre-cat in which the transient HC (and CO) gas performance is required. In this model, the parameters shown below are used; the random pore model for a gas diffusion, HC adsorption capacity as a function of temperature, HC desorption rate and HC reaction rate. Calculated catalyst performance correlated to the experimental results, thus validating the model. Another case is a modeling of DOC + CSF in which active regeneration of CSF is required. The CSF is used for diesel exhaust soot filtering, and the accumulated soot is periodically combusted to regenerate the CSF. Additional fuel is supplied to the DOC by post injection and/or fuel dosing into the exhaust pipe upstream of DOC and the resulting exotherm provides the heat for soot combustion on the CSF. In this study the uniformity of soot regeneration in the CSF was investigated as a function of fuel supply uniformity to the DOC.
What is CSF used for?
The CSF is used for diesel exhaust soot filtering, and the accumulated soot is periodically combusted to regenerate the CSF. Additional fuel is supplied to the DOC by post injection and/or fuel dosing into the exhaust pipe upstream of DOC and the resulting exotherm provides the heat for soot combustion on the CSF.
Is exhaust a pollutant?
The carbon dioxide (CO 2) contained in automotive exhaust is not classified as a pollutant. However, it is one of the substances responsible for the greenhouse effect and the global climate change. In the period since 1920 global atmospheric CO 2 has risen continually from roughly 300 ppm to 380 ppm in the year 2005.
Why are gas engines important?
Gasoline engines for passenger cars have been developed to generate more power and reduce emissions at the same time. Therefore the engine systems have become complex with a number of subsystems.
Is a TWC sufficient for a direct injection engine?
As a result, a TWC is not sufficient, since the NO X cannot be converted under lean conditions.
What is selective catalytic reduction?
Selective catalytic reduction (SCR) is about to be introduced for the reduction of nitrogen oxides in vehicle exhaust gas. For several years this technology has been a proven means of removing nitrogen oxides from exhaust gases of fossil fired power plants. Ammonia (NH 3) has proven to be the reducing agent with the greatest selectivity in this respect. As ammonia is a toxic substance the actual reducing agent used in motor vehicle applications is urea. Urea is manufactured commercially and is both ground water-compatible and chemically stable under ambient conditions.
What is the purpose of a Lambda sensor?
Lambda-Sensors control the air fuel ratio of the engine and catalyst performance in order to get the best possible conversion of the pollutants.
What tools are poisoned by carbon monoxide?
Many people using gasoline-powered tools such as high-pressure washers, concrete cutting saws (walk-behind/hand-held), power trowels, floor buffers, welders, pumps, compressors, and generators in buildings or semi enclosed spaces have been poisoned by carbon monoxide (CO). CO can rapidly accumulate (even in areas that appear to be well ventilated) ...
What is NIOSH notification?
Through the NIOSH Worker Notification Program, NIOSH notifies workers and other stakeholders about the findings of past research studies related to a wide variety of exposures. The links below present archival materials sent to participants in studies related to toll collectors.
What are some examples of CO poisoning?
Examples of such poisonings include the following: A farm owner died of CO poisoning while using an 11-horsepower, gasoline-powered pressure washer to clean his barn. He had worked about 30 minutes before being overcome.
What to do if you have a symtom?
If you have any symptoms, immediately turn off equipment and go outdoors or to a place with uncontaminated air. Call 911 or another local emergency number for medical attention or assistance if symptoms occur. Do NOT drive a motor vehicle–get someone else to drive you to a health care facility.
What is a constant speed exhaust fan?
Constant speed exhaust fan – Design a ventilation system that runs an exhaust fan at constant speed 24/7 (or when the garage is occupied) to continuously exhaust air from the space:
Can a garage vent sensor read CO?
Additionally, some sensors can’t read CO levels below a certain temperature. If a garage ventilation system is designed in a colder climate, there should be a built-in response to low temperatures that will override the exhaust fan to run at constant speed if the sensors are limited.
Is carbon monoxide a problem?
Or that carbon monoxide is not a problem because they are in a huge building with lots of open space, like in an ice skating arena. Unfortunately, a “loose” building, or an open door, or a large space does not guarantee that a person will not become ill from carbon monoxide or even die. CO is a highly toxic gas, ...
Is CO a poison?
The fact that CO is a colorless, odorless, tasteless, and non-irritating poison compounds the problem. When exposed to high concentrations persons become dizzy, are unable to stand or move out of the space, and often collapse. The brain does not received sufficient oxygen during a CO exposure resulting in confusion.
How does cataclean work?
Cataclean also has an immediate effect on engine performance by cleaning and rejuvenating the fuel systems, injectors and valves, and optimising the combination and ignition of the fuel mixture. This results in better throttle response and improved fuel consumption.
What is cataclean used for?
A British-manufactured product, Cataclean, is available in two different patented chemical formulas, one for petrol engines and the other for diesel. For use in cars, vans, trucks and motorcycles, both formulas clean the fuel and exhaust system, improve fuel economy, and lower emissions.