Upgrading of existing precipitators to give reduced particulate emissions

Many of the Lodge-Cottrell precipitators operating on UK power plants were designed and installed at least 20 years ago to specifications which related collection efficiency to MCR gas volume. The efficiencies ranged from 98.5% to 99.3%. Since the plants were installed, legislative levels for dust emission have been reduced. This has lead to the development of a practical precipitator design improvement programme aimed at meeting current legislation within the existing casing. The casings represent a high proportion of the total plant cost and, provided the required precipitation performance can be attained, this improvement programme represents a very cost-effective upgrade