EFFECTS OF PROCESS TECHNOLOGY ON THE BEHAVIOUR OF MERCURY IN THE CLINKER BURNING PROCESS

Abstract

In the European Incineration of Waste Directive, which had to be adopted by national law by the end of 2002, a limit value of 0.05 mg/m³ for mercury (Hg) is specified [1]. In Germany the implementation of the limit value into national law is taking place by amendment of the 17th Ordinance of the Federal Environmental Impact Law. (17. BImSchV) [2]. In this Ordinance, a limit value of 0.03 mg/m3 for mercury had already been introduced early in 2001 for waste incineration plants. For co-incineration plants, such as for example cement works, this value applies only for the exhaust gas flow from the wastes. With the current amendment of the 17. BImSchV, the requirements for co-incineration plants are to be raised still further. They are largely to be made equivalent to the dedicated waste incineration plants. As in the European Incineration of Waste Directive, demanding emission limit values particularly for the co-incineration of wastes in production plants. They replace the so-called “mixing rule” which had to be previously applied. Different from the European Incineration of Waste Directive the 17. BImSchV sets a mercury limit value for cement works of 0.03 mg/m3 as the daily average value. This limit value is independent of the waste substitution. Under an exemption rule, a limit value of 0.05 mg/m³ as the daily average can be specified, if proof can be provided that the mercury emissions are predominantly raw material-based and do not originate from the wastes. Mercury