The rising pollution has started to take effect on the environment and the way of living. Numerous solutions have come up to lower the impact of pollutants, but how effective are they?
What is a Tier 4 Engine?
The Tier 4 Final technology is one of the growing methods that can help reduce the number of pollutants and emissions. It works together with a light Exhaust Gas Recirculation system to meet proper emission standards.
At Volvo Penta, they use an efficient SCR Technology that requires less maintenance. The smart combination of the SCR and light EGR system means that the engine’s installation is quicker than other Tier 4 engines that use many components.
Lastly, having few components can lessen the instances of system malfunction.
What are the Essential After-Treatment Strategies of Tier 4 Engines?
The decrease in emissions from diesel engines because of this Tier 4 technology has been astounding. Modern diesel motors have become one of today’s safest central movers. Some of these enhancements include popular high-pressure rail injection technologies, injector solenoids that regulate electronically, and a sophisticated turbocharging.
The Tier 4 engines require more care as it needs an after-treatment, unlike the previous Tier 2 and Tier 3 engines.
There are three significant techniques used for exhaust Tier 4 after-treatment:
- Selective Catalytic Reduction Technology (SCR): Combined combustion gases with ammonia (urea or DEF, fuel emission liquid) and transferred to a catalyst. To handle 20 gallons of diesel gas, approximately 1-gallon DEF is needed.
- Diesel Particulate Filter (DPF): It operates by using a mechanical filter to capture soot particles after partial catalyst oxidation. The trapped ions are incinerated at certain times during the procedure.
- Gas Exhaust Recirculation System (EGR): An EGR operates by returning a tiny quantity of condensed exhaust fuel to the combustion room. This decreases the temperature of combustion and efficiently reduces NOx manufacturing. However, EGR improves particulate emissions, so a DPF is required to comply with the latest Tier 4 rules.
How it Works
The EPA rules aim to decrease two primary exhaust pollutants dramatically. Particular material, or PM, has mainly harmful byproducts such as coal dust which earlier unimpededly squeezed out the motor. Another example is oxygen nitrates which are a central component in air pollution.
The Tier 4 Final rules required a dramatic decrease in NOx concentrations. It was more than EGR could manage on most motors alone. The alternative was to introduce a new after-treatment ignition scheme known as the SCR.
In an SCR scheme, waste moves through a mixture of DPF or DPF/DOC first and then into a catalytic tank with a fog of air and urea. Urea is a popular chemical used for business fertilizers.
The mixture of urea/water is frequently called the diesel exhaust fluid or DEF. In the existence of the compressor, the engine and DEF convert the NOx mainly into nitrogen and water.
With the upgrade from a Tier 3 to Tier 4 technology, engine features have evolved as well. They are now more fuel-efficient, cleaner, and safer for the environment.