To track emissions to air under new requirements, a portable Gasmet Dx 3000 FTIR analyser was rented from Quantitech by Lafarge Lime's Whitwell Works in Derbyshire, and is now a permanent feature
Lafarge Lime's Whitwell Works in Derbyshire is situated on one of the best quality dolomite (magnesium limestone) deposits in the UK.
The quarry provides the raw material for a range of specialist burnt dolomite products and aggregates.
Dolomet, Dolofrit and Dolopel are respectively used as steelmaking fluxes, for kiln repairs and for the production of high quality refractory bricks and are produced in two large rotary kilns. Each product requires slightly different firing temperatures and kiln residence times, so accurate process control is essential to maintain product quality.
Changing legislation required an additional number of analytes to be measured in addition to the continuous monitoring already in place on site.
To track the emissions to air under these new requirements, a portable Gasmet Dx 3000 FTIR analyser was rented from Quantitech Ltd on a trial basis.
The unit performed so well that the unit became a permanent feature of the measurement regime.
The nature of the raw material and the fuels require that any monitoring system must be able to differentiate between a wide range of different analytes: CO2, CO, SO2, HCl, HF and nitrogen oxides are all measured simultaneously, as are a range of hydrocarbons as indicators of Total Organic Carbon emissions.
Many are at trace concentrations, in the presence of 15 - 18% levels of CO2. Sampling is automatic using a system developed jointly with Quantitech.
Raw data from the analyser is processed by the dedicated Calcmet software and transmitted to the control room where it is used to control the process.
According to John Collins of Lafarge Lime, the ease with which the instrument can be transferred from one kiln to another and the very low maintenance requirement have been notable features of the Dx 3000.
