Remote monitoring of industrial emissions by combination of lidar and plume velocity measurements

We describe a new method for gas flux measurements that is a combination of differential absorption lidar (DIAL) and wind videography. The wind speed was measured by an imaging method that calculates the horizontal displacement of the plume with cross-correlation techniques. High spatial and temporal resolution is achieved with histogram equalization and window-filtering techniques. Simultaneous measurements of the distance, the direction of the plume and the integrated concentration were provided through the lidar measurements. Alternative methods of measuring the wind speed at different heights have been used to validate the precision and accuracy of the new method for different geometrical configuration. An example of remote mote SO2 flux measurements from a pulp and paper mill is presented, which shows a very good correlation with in situ measurements taken at the source.