Although the reserves of high-alkali coal represented by Zhundong coal is huge

the problem of coking on heating surface of the boiler is prominent during co-firing high-alkali coals in thermal power units

which not only reduces the boiler thermal efficiency

but also seriously threatens the safe

stable and economic operation of the unit. In order to solve this problem and promote the utilization of high-alkali coal

this paper reviews the researches on coking of the heating surface of high-alkali coal boilers and the prevention. Up to now

extensive researches have been carried out at home and abroad on the characteristics of coking on the heating surface of coalfired boilers

coking mechanism

influencing factors

prevention and control measures

and so on

and fruitful research results have been achieved. On the basis of controlling the quality of coal

improving boiler structure

and optimizing boiler operation

the preparation of coating on the heating surface of boilers has also become an important technical path for preventing and controlling coking. In the future

the coating should possess excellent comprehensive properties such as high temperature resistance

corrosion resistance

wear resistance

thermal conductivity

thermal fatigue and so on

while having outstanding coking resistance. Meanwhile

the coating also should have desirable preparation economy and preparation efficiency

especially the on-site applicability.