The main sources of dust and nitrogen oxides in our country are industrial production, accounting for 83% and 71%, respectively.If the industrial sector is further subdivided, the electric power (especially thermal power), steel and building materials industries are the main industries that emit smoke, dust and nitrogen oxides.These three industries account for more than 70% of the emissions of these two pollutants from all industries.

In order to achieve the goal of emission reduction, in 2010, my country implemented a production restriction action using the brake to restrict electricity as a compulsory means.After 2015, environmental protection requirements have continued to increase, and production restrictions have become more logical in the name of environmental protection, and the implementation has become significantly stronger.In the three years from 2015 to 2017, environmental protection production restrictions have become the norm in Beijing, Tianjin, Hebei and other regions.

However, there is an obvious restriction on large-scale production restriction and emission reduction, namely: it can only be carried out if the production-restricted industry is in a state of obvious overcapacity, oversupply, low product prices, and weak industry profitability.At this time, the production restriction will help to achieve the goal of improving air quality on the one hand, and on the other hand, it will help to improve the supply and demand relationship of these industries, and the profit margin will return to normal levels.

Once the supply and demand relationship of these industries improves, production restrictions will continue. Although the control of the air environment is still beneficial, it will lead to a reverse imbalance in the supply and demand relationship, resulting in a significant increase in product prices, thereby increasing the cost of downstream industries and causing unnecessary harm to the national economy.

The significant rebound in steel and cement prices since 2016 has restricted the space for production restrictions in these industries.Especially in 2017, the price and profit margin levels of these industries have hit new highs since 2012, making it difficult to continue the road of large-scale production restrictions in 2018.This can be seen from the environmental protection requirements of the Beijing-Tianjin-Hebei region from 2018 to 2019 issued by the Ministry of Ecology and Environment. In the previous year, both PM2.5 and PM10 must be reduced by more than 15%, but this year this indicator has been adjusted to 5%.