Rågodsets temperaturförändring: Från slurry till råkula i KK2
Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
LKAB, Sweden's eighth largest export company, aims to improve energy efficiency and reduce their carbon footprint. This thesis aim is to measure the temperature change of the moist material as it moves through the cold part of the pellet plant KK2. This is important because large amounts of hot air are used in order to dry the pellets. If the pellets have a higher temperature when they enter the dryer the temperature of the air coming out from the drying process will be higher. This allows the air to carry more water, resulting in a more efficient drying process.In the early parts of the project several tours of the plant was done in order to determine where the temperature measurements should be done. Several interviews with employees at LKAB were done to find out whether there were any external factors that could affect the outcome of the measurements. After the interviews 8 measurement zones for temperature measurement on the material and 4 log zones for measuring the temperature and humidity in the environment where chosen. To verify the measurement zones two sample measurements where done. The sample measurements confirmed that the easiest way to perform the measurements where to take samples directly from the conveyor belts and then measure the temperature using a thermometer with an attached thermocouple.The measurements showed that the ambient temperature affects the material much. The processes that had the greatest contact with the environment also had the largest temperature change. From the measurements it was also seen that it was the filters that had the largest temperature change. But also the conveyor belts and roller circuit had severe temperature changes.The project also aims to confirm the measured temperatures with theoretical calculations. It turned out that the theoretical models were not complex enough to explain the temperature change that occurred and therefore could not explain the measured temperature.In conclusion, it was established that:• The temperature change in the material greatly depends on the ambient temperature.• The largest temperature losses are found in the filters, the second largest in the conveyor belts and the third largest is found in roll circuit.• A higher temperature of the slurry gives the material a better chance to reach the grate with a higher temperature.• The thermodynamic models are difficult to do properly because of the high complexity of the process.• To reduce temperature losses the process should be protected from the environment whenever possible. The indoor climate in KK2 should also be stabilized so that the material is not exposed to irregular temperature change.
Place, publisher, year, edition, pages
2014. , 75 p.
Teknik, LKAB, energi, kulsinterverk
IdentifiersURN: urn:nbn:se:ltu:diva-42454Local ID: 077bc8bd-efff-47f2-9ddc-5f5a6057b344OAI: oai:DiVA.org:ltu-42454DiVA: diva2:1015675
Subject / course
Student thesis, at least 30 credits
Sustainable Energy Engineering, master's level
Validerat; 20140811 (global_studentproject_submitter)2016-10-042016-10-04Bibliographically approved