A couple of days ago, I watched a documentary that went viral in Chinese internet. The name of the documentary is “穹顶之下(Under the Dome)”, filmed by a famous Chinese TV reporter called 柴静 (Jing Chai).
If you are concerned about the environment issues in China. It will be a very informative piece and you will not be bored. I have to admit that I am not an environment expert, so I got to learn some quite astonishing facts from it.
One of the topic that caught my attention is the big contribution of the Diesel to the overall air pollution. So I decided to read a little more from the internet. Here is how I understand about this issue.
How does Diesel contributing to the pollution?
Common pollutants include unburned hydrocarbons (HC), carbon monoxide (CO), nitrogen oxides (NOx) or particulate matter (PM). You can read some interesting aspect of Diesel pollution from here.
How are the Diesel regulated?
Each country has their own emission standards. In some countries the Diesel and gasoline are regulated separately, such as Europe and China. In United States, the regulation are unified for gasoline and diesel.
In previous regulations the focus has been focused on the CO2 emission and MPG. While in the new standards the NOx has caught more attention. It is quite technical for reading the standard specifications. Many also use different units, for example, the NOx regulation, different countries use units as g/km, g/BHP.Hour and g/kW.Hour.
Here are some website that composite the various standards. It is much easier to get some idea of how the regulations are evolving.
If you only read from the standard (assume that they were enforced), China is actually not far behind from the leading pack such as United States, Europe and Japan. The latest China IV standard (similar to the EU IV) is only 10 years late than the US standard. India on the other hand does not attempt to move beyond EU III standard as of 2020.
What are the technologies for Clean Diesel?
To get some idea of the technologies available for clean diesel, we could take a look at the EPA Clean Diesel website and follow where are the research money goes.
Here are some good read about using Urea to reduce NOx emission from Diesel engines. You are reading it correctly, Urea is already in use (at high concentration around 35%, so don’t try to pee in your tank) for this purpose.