Emissions Compliance What’s Up For 2010?

November 5th, 2007

By Fred Shaefer

I remember when changes started to take place in cars to meet the 1970 Clean Air Act. These were the first standards for reductions in automotive emissions. I had just learned to adjust a set of points so the engine would actually run.

Over the next decade I saw changes that added hoses to connect things like charcoal canisters, exhaust gas re-circulation valves, air intakes, manifolds, sensors, sensors, and more sensors, and some things that I am still not to sure what they are for. The catalytic converter was placed in the exhaust system in 1975 and the change to unleaded gas took place. Fuel injection, electronic ignition, computerized engine control and onboard diagnostics systems are now standard on all new cars. When I was younger I liked to work on my cars, now I do not even lift the hood.

During most of this time heavy duty truck diesel engine emissions were essentially left unregulated. Why? It doesn’t really matter but in the early 1990s the Environmental Protection Agency started to push the truck diesel engine manufacturers down the same road. (I couldn’t resist the pun.)

The 1990 Clean Air Act was amended to include provisions to tighten controls on particulate emissions from diesel engines. In 2000 more stringent emission standards for new heavy-duty diesel engines were proposed that have been phased in this year (2007). Many of the changes for diesel trucks are similar to those that were made for automobiles such as computerized engine control, electronically controlled injection systems, and the important change to ultra-low sulfur fuel. The addition of better air and fuel management systems, particulate filters in the exhaust stream, and exhaust gas re-circulation technology played a major roll in meeting the 2007 requirements.
OK, these are things that we should all be familiar with. By we, I mean those of us who are involved in building, selling, equipping, buying and using fire apparatus. We all should have some idea about what is coming for 2010, right? Well I had no clue.

In trying to find an answer to what seemed to be a simple question Emissions Compliance, What’s up for 2010?, I discovered that there was no simple answer. My thinking was that I could go to the EPA regulations, find the section on fire trucks and there would be the information on what was going to happen. No such luck.
The Environmental Protection Agency (EPA) is a cabinet level department (that puts it high up in the executive branch of the federal government). One of the things that the EPA does is develop and enforce regulations that implement environmental laws enacted by Congress (i.e. the Clean Air Act). Simply put this makes the EPA a kind of environmental police force. OK, we all pretty much know this. So the question is how do things get changed that help us comply with any new rules, regulations, or laws that the EPA puts forward? Believe it or not the government has a plan in place and it does seem to have been working. Here is how it tracks down to us.

The U.S. Department of Energy (DOE) is also a cabinet level department and of course responsible for the U.S. National Energy policy. The DOE oversees many programs, including one that focuses on developing energy technologies.

The Office of Energy Efficiency and Renewable Energy (EERE) leads the Federal Government research, development, and deployment efforts for energy that is clean, abundant, reliable, and affordable. EEREs role is to invest in research and development that may have high cost and risk but is critical to the nations energy future. This includes high-risk, high-value research that would not be sufficiently conducted by the private sector acting on its own. It does this by creating partnerships between the private sector, state and local government, DOE national laboratories, and universities. These partnerships are involved in research dealing with technologies in areas such as: Biomass, Geothermal, Hydrogen, Fuel Cells, Solar Energy, Wind, and Hydropower. (You may not see it yet but we are working down to where fire apparatus fit in.)
One of the programs that EERE oversees is the FreedomCAR and Vehicle Technologies (FCVT) Program. The FCTV focuses on developing technologies in the highway transportation sector for alternative power, reducing energy use, and to decrease pollution. The technology areas that are targeted include: hybrid, electric propulsion and fuel cell powertrains; fuel and fuel component resources including biomass, vegetable oils, and hydrogen fuel cells; materials used in body, chassis, and power train systems; engine combustion efficiency and mobile emissions.

The FCTV is made up of two partnerships. The FreedomCAR and Fuel Partnership covers the development of emission- and petroleum-free cars and light trucks along with the fueling infrastructure. The 21st Century Truck Partnership address the research and development needs of commercial trucks and buses.

The 21st Century Truck Partnership is an agreement between the Federal Government and the Heavy Duty Vehicle Industry. There are, as best as I can tell, 4 federal government partners, 12 national laboratories, and 16 industrial partners involved. This group has five critical areas that they are focusing on to reduce fuel usage and emissions and at the same time improve heavy duty vehicle safety. They are Engine Systems, Heavy-Duty Hybrids, Idle Reduction, Parasitic Losses, and Safety.

It is important to note at this point that the research and development going on is focused on heavy duty vehicles that are involved in the moving of freight and passengers (busses). The fire services are impacted because we use the same chassis and engines. The changes in technologies that come out of any one of these areas may have an impact on fire apparatus. On to emissions.
The partners that are involved in the Engine Systems area are looking at technologies that deal with engine design, fuel and combustion characteristics, and exhaust treatments. It makes sense that the key players here would be the engine manufacturers.

Before I get into what might be for 2010 let me recap some of the things that have happened coming into 2007. I think a key change was the switch to Ultra Low Sulfur Diesel (ULSD) fuel. Just using ULSD on its own helps reduce sulfates, particulate matter, carbon monoxide, and nitrogen oxides from the exhaust. The really important thing it does is to allow new exhaust emission control technologies to be put into play. You can think of it as having the same impact that the change to unleaded gas had on the automobile with a major exception, ULSD is backwards compatible and it can be used in older engines.

21st Century Truck Partnership Industrial Partners

Allison Transmission
BAE Systems
Caterpillar, Inc.
International Truck & Engine Corporation
Cummins, Inc.
Mack Trucks, Inc.
Daimler Chrysler Corporation
NovaBUS
Detroit Diesel Corporation
Oshkosh Truck Corporation
Eaton Corporation
PACCAR, Inc.
Freightliner LLC
Volvo Trucks North America, Inc.
General Motors Corporation
Honeywell, Inc.

Some of the technologies used for meeting 2007 requirements are:

  • Exhaust Gas Recirculation (EGR) – reduces nitrogen oxides from forming during combustion by recirculating cooled oxygen depleted exhaust gases back into the cylinder
  • Diesel Oxidation Catalyst (DOC) – removes carbon monoxide and hydrocarbons in the exhaust stream
  • Diesel Particulate Filter (DPF) – removes particulate matter in the exhaust stream.

These along with improvements in technologies for intake air handling, combustion, and fuel delivery have made the North American on-highway diesel engine the cleanest they have ever been.

Having said that there is more to come. For 2010 emissions of Particulate Matter (PM) and Nitrogen Oxides (NOx) must be lowered even more and this brings us to the question at hand Emission Compliance, Whats up for 2010?

The chatter around the water cooler is that Selective Catalytic Reduction (SCR) technology using urea as the reducing agent will be rolled out by most engine manufacturers. I can understand why many would think this. The SCR system using urea is not a new technology. It is proven and currently used with stationary engines, on marine vessels, and has been employed to some degree in Europe to meet the 2005 emissions requirements there.

How does it work? In a nut shell the reducing agent urea (also known as Adblue) is injected into the exhaust down stream of the particulate filter. The mixture will pass through the SCR catalyst where the nitrogen oxides are converted into harmless nitrogen and water. Seems pretty simple, so what are some of the drawbacks?
First there is the added hardware on the vehicle: a tank for the urea, a metering/pump/injection unit that would have to be electronically controlled, a way to heat the tank/pump/lines if used in cold climates, and an SCR catalyst device. Second the distribution infrastructure for the urea needs to be put in place. Third there would have to be safeguards in place to ensure the emissions system can not be circumvented or the vehicle operated without urea in the tank.

Lean Nitrogen Oxide (Lean-NOx) Catalyst (LNC) technology functions similar to SCR. The difference is that it can use hydrocarbon as the reducing agent. Hydrocarbons that are already present in the exhaust or injected diesel fuel act as the reactant when the exhaust stream passes through the catalyst. The advantage here is less new hardware and no new infrastructure, the fuel is already on the vehicle. The down side is that a high percent of reduction in nitrogen oxide is not really there yet. Keep in mind that we are looking at what might be for 2010 and this technology along with nitrogen oxide absorbers is still under development.

Lean Nitrogen Oxide (Lean-NOx) Traps (LNT) also known as NOx Absorber Catalyst actually trap and store the nitrogen oxide under normal lean running conditions. The LNT undergoes a regeneration cycle where a fuel-rich exhaust condition is created that reduces the stored nitrogen oxides into harmless nitrogen. These devices do have a problem with sulfur. Even with the ULSD they need to go through a desulfurization cycle to maintain their efficiency.

Selective Catalytic Reduction, Lean Nitrogen Oxide Catalysts, and Lean Nitrogen Oxide Traps are all aftertreatment technologies. They are part of the exhaust system and work along with Diesel Oxidation Catalysts and Diesel Particulate Filters to clean up emissions after combustion. There is another part to the story on the opposite side of the exhaust manifold.

Engine combustion technologies look to deal with the problem of cleaning up emissions by using in-cylinder techniques that prevent the bad stuff from forming in the first place. This is accomplished through the manipulation of fuel and air delivered into the cylinder and how it burns. Exhaust Gas Recirculation currently used on many vehicles that returns some of the exhaust gas back to the intake of the cylinder is this type of technology.

The advancements that have been or will be made in this area are coming about mostly because of advances in electronic controls. Investigating these technologies to try and understand what developments might come into play over the next few years is making my head spin in three different directions. The next paragraph is a list of some of the technologies being researched. Unless you really have a need to know I would suggest that you just skip over it.

The following list (in no special order) is for those who may want to do some of their own investigating:

  • Low Temperature Combustion (LTC)
  • Homogeneous Charged Compression Ignition (HCCI)
  • Stratified Charged Compression Ignition (SCCI)
  • Dilute Clean Diesel Combustion (DCDC)
  • Dilution Controlled Combustion System (DCCS)
  • High Pressure Direct Injection (HPDI)
  • Homogeneous Charged Late Injection (HCLI)
  • Highly Premixed Late Injection (HPLI)
  • High Pressure Common Rail (HPCR)
  • Premixed Charge Compression Ignition (PCCI)
  • Clean Diesel Combustion (CDC)

So what new doors are opening because of these advancements in electronic control technologies? Well we all have some idea of how most internal combustion engines work, mix air with fuel in a confined space (the cylinder) under some pressure, get it to ignite (explode) and push a piston that does some work (make the wheels go round). Back in the day you would turn a screw on the carburetor to adjust how much fuel squirted, set the valves, turn the distributor or mess with the points (remember points?) you would use your ear (sometimes a timing light) and make the motor purr like a kitten. Today we have fuel injection, hydraulic valves, electronic ignition, sensors, sensors, and more sensors all tied together by the computer.

Ah, the computer, and all of those electronic controls. How about instead of just squirting fuel into the cylinder you could inject it in at a very precise time, maybe multiple times, and under pressure. Voila, cleaner burning combustion with less exhaust emissions. (The Common Rail Injection System in use today does this.) The next step might be shaping the fuel spray and how it disperses in the cylinder to produce an even better burn. Injection Rate Shaping, it’s in the works. What if you could fine tune how, when, and where air and fuel combine to provide the optimum mixture, pressure, temperature, and adjust it on the fly depending on engine load and power needs? Yeah, it’s in the works too. In cylinder combustion research continues.

OK so what’s next? If you look at the direction most technologies have moved coming into the 21st century it would be digital. A digital engine, well don’t laugh, guess what its here!

This entry was posted on Monday, November 5th, 2007 at 12:00 am and is filed under commentary articles. There are One Response to “Emissions Compliance What’s Up For 2010?” :
admin Says:

Considering recent developments, I thought this story deserved a bump. Its a great description of where we were 5 years ago.

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