Standards Development

Scope

This proposal specifies specifies the terminology, classification, technical conditions, selection principles and methods of wear-resistant refractory materials used in different high-temperature areas of circulating fluidized bed boilers. It applies to circulating fluidized bed (CFB) boilers with a capacity of 410 t/h and above. Circulating fluidized bed boilers of other capacity classes could also use this evaluation standard as reference.

Purpose

As a clean and efficient coal-fired power generation technology, the circulating fluidized bed (CFB) boilers are constantly developing toward the direction of large-scale and high-parameterization. At present, there are more than 5000 CFB boilers in the world. There has been more than 3000 CFB boilers in China, accounting for 60% of the total number of CFB boilers all over the world, while CFB boilers above 410t/h have more than 500 units.

There has been nearly 100 million KW of installed fluidized bed boilers in China, which is the country with the largest number and capacity of CFB boilers. Among them, the amount of supercritical CFB boilers is more than 40. The individual capacity, capacity scale and technical advancement of CFB boilers in China have reached the world leading level. In this field, China has not only built a complete system consisting of design, manufacturing, installation, operation and maintenance, but also produced many theoretical innovations and accumulated rich practical experience in engineering.

Due to high operating temperature and frequently changed furnace temperature in CFB boiler, the circulating thermal shock is easily resulted in. At the same time, there are a large number of high-speed and high-temperature solid particles in the furnace, which are constantly washing the heating surface. Coupling with the presence of corrosive gases and other media, the complex wear process are formed and the operation environment becomes relatively harsh. To solve above problem, the main method of maintenance is to lay wear-resistant refractory materials in certain areas.

This technical specification divides the high temperature area in CFB boiler into water-cooled aridistribution plate; water-cooled wall; screen-type heating surface; flue window of the furnace; cyclone separator and its import and export flue; returner; external bed and other different parts, and put forward the terminology, classification, technical conditions, selection principles and methods of wearresistant refractory materials used in different high temperature areas of CFB boiler.

The type of wear-resistant refractory materials laid in different areas of CFB boilers varies greatly, and the selection of wear-resistant refractory materials is especially important for guiding the operation and construction of CFB boilers. This problem can be effectively solved by establishing unified standards and technical guidelines, which will not only improve the influence of CFB boiler technology in the world, but also promote the wear-resistant refractory materials industry as a whole to develop for the better.