Within the global steel-and metal industry there is a growing need for new sensor systems to measure and control the industrial process. New technologies for new sensors are continuously being developed for an ever growing market. The growth in the steel making industry is based on ore and Blast Furnaces therefore play an increasingly important role for the production of hot liquid iron and steel. We present a new interferometer micro wave system to makethree dimensional topographic maps of the blast furnace burden surface. The Blast Furnace process is one of the oldest industrial processes. The furnace is tall and round. Layers of Coke ands iron ore are successively laid, and air, pre-heated to 1200 °C, as fuel to the process. The coke and iron layers become semi-liquid and then liquid in the cohesive zone. The carbon from the coke reacts with the oxygen in the ore (which is Fe2O3or Fe3O4) and form CO and CO2which goes off as off-gas. The iron, now mixed with some amount of carbon, is tapped in liquid form from the bottom. This is then taken to a converter, where oxygen is added to remove the carbon to form the final product of liquid steel.