Emission Limits and Measurement Methods of Exhaust Pollutants of Diesel Engines for Non-road Mobile Machinery, China Stage I and II, GB20891-2007, Standard, diesel engines with power less than 560kW for non-road mobile machinery; A second engine used on the road for the installation of vehicles carrying people, cargo, etc.; Rated net power does not exceed 37kW, used for Marine drive, can refer to this standard implementation. The specific emissions of CO, HC, NO and PMD in diesel exhaust pollutants for non-road mobile machinery are shown in Table 1 for stage I and Table X for stage II
Emission Limits and Measurement Methods of Diesel Engine Exhaust Pollutants for Non-Road Mobile Machinery, China Stage 3 and 4
The specific limits are as follows:
The comparison of the above non-road diesel engines in the three standards in the two countries and one country shows that the third stage has the following changes:
1. The emission limits of pollutants are tightened
This standard limit value does not require China's phase II limit value comparison is shown in Table 32.
Table 32 Comparison of non-road Stage II and III restrictions
THC+N Rated net power NOx PM THC CO Ox, P, max, g/kWh, g/kW, g/kWh, g/kW, g/kWh,, kW, h,
II III II III II III II III II III 130? P? 560 3.5 3.5 1.0 / / / max6.0 4.0 0.2 0.2
75? P,130 5.0 5.0 1.0/6.0 / / 4.0 0.3 0.3 max
37? P,75 5.0 5.0 1.3/7.0 / / 4.7 max0.4 0.4
19? P,37 5.5 5.5 1.5 / / / max8.0 7.5 0.8 0.6
8? P,19 6.6 6.6 / / - / 9.5 7.5 0.8 0.8 max
10.
P,8 8.0 8.0 / / / / 7.5 1.0 0.8 max5
From the above table, we can see that the main changes of pollutants in each power segment are THC+NOx.
CO did not change at all,PM only 19? P,THC+NOx is reduced by about 30%-40%,max37 and P,8 power segments are reduced by 25% and 20%, respectively. max
The number of models below 19kW in China is huge, and the emission level is low, and the pollutant sharing rate accounts for more than 90% of non-road mobile machinery, which needs to be focused on control.
2, increase the durability of the technical requirements
Introduction of the concept of effective life, which is the period of service for which diesel engines and their emission control systems, if any, for non-road mobile machinery are guaranteed to operate properly and comply with the emission limits for gaseous pollutants and particulate matter, and which has been confirmed at the time of type approval. Detailed requirements are shown in the table below:
Durability time requirement
The minimum allowable test time of engine speed effective life in power segment
kW, h, h
P? 37 Any speed 8000 2000 max
Non-constant velocity
5000 1250
Constant speed,3000 19? P,37 max
Constant speed? 3000
3000 750
P,19 Any speed max
3, increase the control requirements of 560kW or more diesel engines
Diesel engines above 560kW are mainly used in large mining machinery, generator sets and so on. Although the amount is small, it should also be controlled in view of the need to reduce the total amount of pollutants. 4, increased the precious metal detection requirements of the post-processing system
The precious metal content of catalytic converter is not closely related to the emission of diesel engine pollutants, and strengthening its inspection is conducive to the emission control of diesel engine pollutants.