9　Boiler Equipment and System

9.1　Boiler Equipment

9.1.1　The boiler type shall be selected in accordance with the following requirements:

1　Boilers，such as CFB boilers and pulverized coal fired boilers，can be selected based on the coal quality，engineering conditions，and heat load characteristics.

2　The boilers having the same capacity should be of the same type.

3　When meteorological condition permits，outdoor or semi-outdoor boilers should be used.

9.1.2　The number and capacity of the boilers of thermal power plants shall be determined based on the design heat load through comprehensive techno-economic comparison.The boiler capacity shall be selected such that the steam inlet flow of the turbine is not less than the boiler minimum stable load without oil supporting under the minimum heat load condition.

9.1.3　If no other heat source is available，more than one boiler should be installed in phase I of a thermal power plant.

9.1.4　If the boiler with the largest capacity is stopped，the output of the rest boilers in a thermal power plant shall meet the following requirements:

1　It can accommodate the steam consumers'steam needs for continuous production.

2　It can supply 60%-70% of the heat load for heating，ventilation，and domestic use during winter.In severe cold regions，the upper limit shall be taken.

9.1.5　For extended power plants where the main steam piping is arranged in manifold system，the capacity of the new boilers shall be determined considering the capacity of existing ones.

9.1.6　The capacity and number of the boilers of condensing power plants shall comply with the following requirements:

1　The capacity of the boiler should be commensurate with the steam inlet flow of the turbine at the maximum continuous rating（TMCR）.

2　One steam turbine-generator unit should be provided with one boiler.No standby boiler shall be provided.