High-efficient cleaning and maintenance liquid of diesel engine SCR system

Abstract

The invention provides a high-efficient cleaning and maintenance liquid of a diesel engine SCR system. The high-efficient cleaning and maintenance liquid includes the following components: a complexing agent, a surfactant, a cosolvent, ammonia water and the balanced being urea. The high-efficient cleaning and maintenance liquid can prolong the service life of a catalyst, can improve the effect of the catalyst in the SCR system, can improve the efficiency of tail gas treatment and can reduce the use cost of vehicle-use urea.

Description

technical field [0001] The invention relates to a high-efficiency cleaning care liquid for a diesel engine SCR system. Background technique [0002] The following problems will occur during the long-term use of automobile exhaust treatment fluid: [0003] 1. The urea solution contains a small amount of metal ions, which will gradually lead to catalyst poisoning and failure after being used for a certain period of time, eventually causing the SCR system (SCR is the abbreviation of SelectiveCatalyticReduction, a selective catalytic reduction converter, referring to the urea injection control reaction system) to be unable to effectively treat the car exhaust; [0004] 2. When urea is heated above 200°C, it will polymerize to produce viscous water-insoluble polycyanamide, which will adhere to the nozzle and cause nozzle blockage; [0005] 3. During the working process of the SCR system, when the nozzle is opened to spray urea solution, the exhaust gas of the vehicle will recoi...

AI Technical Summary

Problems solved by technology

[0003] 1. The urea solution contains a small amount of metal ions, which will gradually lead to catalyst poisoning and failure after being used for a certain period of time, eventually causing the SCR system (SCR is the abbreviation of SelectiveCatalyticReduction, a selective catalytic reduction converter, referring to the urea injection control reaction system) to be unable to effectively treat the car exhaust;

[0004] 2. When urea is heated above 200°C, it will polymerize to produce viscous water-insoluble polycyanamide, which will adhere to the nozzle and cause nozzle blockage;

[0005] 3. During the working process of the SCR system, when the nozzle is opened to spray urea solution, the exhaust gas of the vehicle will recoil into the nozzle, producing carbon deposits and other granular dirt. Long-term accumulation will make the nozzle unable to return to its position, eventually resulting in damage to the return spring, and cause nozzle clogging;

[0006] 4. When the SCR system is working, when the nozzle is opened to spray urea solution, due to the high temperature, the chemical reaction between phosphate, carbonate and calcium, magnesium and other ions in the urea solution produces calcium carbonate, calcium phosphate and other water-insoluble scales , leading to nozzle clogging;

[0007] 5. After the nozzle is blocked, it can only be removed for cleaning, which is not only very troublesome, but sometimes it cannot be cleaned and must be replaced, resulting in economic losses for users

[0008] 6. In cold weather, ordinary urea solution is not antifreeze, and the freezing point is too high