A .FGD出、入口烟气挡板打开,旁路烟气挡板关闭
B .FGD出、入口烟气挡板关闭,旁路烟气挡板打开
C .FGD出、入口烟气挡板打开,旁路烟气挡板打开
D .FGD出、入口烟气挡板关闭,旁路烟气挡板关闭