POTENTIAL FOR IMPROVEMENT IN A REFINERY´S STEAM NETWORK OPERATIONAL STABILITY

The topology and operation of a steam network in a large industry is influenced by its past development to a great extent; the same holding true for the SLOVNAFT refinery. Along with commissioning of new conversion technologies, introduction of energy saving measures and shutdown of obsolete units the core of steam production shifts from the Central combined heat and power unit to the local steam sources producing steam from hot waste heat streams. Dimensions of steam pipelines that served the steam transport demand well in the past gradually become either too large or too small, causing the steam to locally cool down and condense or to stream with high velocities. Both cases negatively influence the steam network operation and put more strain on its proper management and its future development projects. Starting from actual operational state analysis that is presented in another contribution, calculations were performed to model future steam network operation. This is anticipated to be seriously influenced by commissioning of new technologies in near future and several proposals have been formulated to ease their impact on its stability. Combined effects of new production units commissioning and the proposed measures were tested in order to select the most promising proposals for further elaboration. The presented results should serve the energy management to prepare action list where considering future investments aimed at steam network evolution.