Madhya Pradesh, India -- (SBWIRE) -- 02/23/2011 -- New Tier 4 emission regulations for tractor engines rated at 174hp, and above, come into effect in just six weeks time. It sounds complicated, but as machinery editor Derek Casey shows, there are just two ways manufacturers will meet the tough new standards.
It can sound like rocket science, all this talk of emissions standards. Between catalytic reductions and cooled recirculation, a farmer would be forgiven for thinking he needs a degree in chemistry before buying a new tractor.
Believe me; it's far easier than it sounds. There are really just two methods that will be used to meet the Tier 4 standards that come into effect on 1 January, 2011.
The first method is selective catalytic reduction (SCR). SCR converts nitrogen oxides to harmless nitrogen and water by dosing exhaust fumes from the tractor's engine with small amounts of 'AdBlue', a urea solution that will be sprayed into the exhaust emissions downstream of the engine.
AdBlue is already used in road haulage on lorries, and a second tank will be needed on the tractor for holding it.
The second method is exhaust gas recirculation (EGR), which recirculates exhaust fumes back into the engine and uses a particulate filter to capture pollutants.
No AdBlue is required, but a bigger engine cooling package is required because you are recirculating hot exhaust gas back into the engine.
So, which method will your preferred manufacturer use?
Case IH
Case IH (through engine supplier, Fiat Powertrain Technologies) will use SCR for medium and heavy duty engines (greater than 100hp), and EGR for light-duty engines (less than 100 hp).
According to Case IH engineers, ''SCR in high-horsepower engines offers the advantages of lower fuel consumption, longer service intervals and better power response than EGR. This is because SCR allows clean, cool intake air without exhaust gas into the combustion chamber, avoiding the need for a larger
cooling system and providing a more complete fuel burn than EGR.
''Because SCR is separate from the main engine function, power and fuel efficiency are not compromised. Engine performance improves because SCR reduces emissions in the exhaust stream, allowing the engine to be tuned for performance and fuel efficiency.
''We are seeing a minimum 10% average operating cost improvement over our Tier 3 engines. Oil change intervals have lengthened to 600 hours because hot exhaust fumes are not recirculated.''
SCR requires the addition of AdBlue, which is commonly used in road haulage trucks and is currently priced at about the same as diesel fuel. Case IH says the AdBlue will be used at a rate of 3% to 5% of diesel fuel.
Taking AdBlue use into account, Case IH claims an average 10% improvement in operating costs over previous models, as a result of fuel savings and reduced oil changes.
MF, Fendt & Valtra
AGCO, including the popular brands in Ireland of Massey Ferguson, Fendt and Valtra, are already using SCR on high-horsepower tractors (including the MF8600 and Valtra S series).
AGCO was the first agricultural manufacturer to feature SCR technology in their Massey Ferguson tractors at the 2007 Agritechnica. AGCO engineers say they selected SCR technology because it is ''the most effective and fuel-efficient method of meeting present and future EPA emissions requirements.''
According to AGCO, SCR will deliver a substantial improvement in fuel economy while reducing emissions.
''Tier III technology alone can achieve NOx reductions in excess of 90% and delivers uncompromised horsepower and torque from a cooler running engine. It also delivers up to 20.8% in fuel savings compared with competing models,'' the company stated.
Service and maintenance needs of the engine are unaffected. Maintenance of the Tier III SCR solution is minimal.
The main diesel particulate filter must be changed every two years or after 4,500 hours of use. The AdBlue is consumed at a rate of approximately 3% of the fuel used. This means that for every 100 litres of fuel used, three litres of AdBlue will be consumed.
http://www.tier3savings.com