Research On Measurement Technology Of Phase Fraction For The Oil-tank Sludge

Oil-tank sludge is a kind of recyclable resource with high oil content. Every year, large amount of oil-tank sludge is produced in the oil industry. If discharged without being processed, it will lead to environmental pollution and resource waste. As the world is facing the growing shortage of energy supply, it is urgent to recycle oil sludge resource and make full use of it. The significances of this research are as follows:1) to provide guidance for the recycling technology of oil sludge; 2) to give a significant decision support for the purchase of oil sludge as commodity. However, up to now, there is no effective method to measure its phase fraction. Hence, it’s urgently needed to find a suitable method which can measure the phase fraction of oil-tank sludge rapidly and accurately.In this research, several commonly used methods for phase fraction measurement were analyzed and summarized. A prototype system based on microwave transmission was designed to measure the water content of oil-tank sludge. A series of experiments were accomplished. Details are as follows:(1) Several commonly used methods for phase fraction measurement were analyzed, including the advantages, disadvantages and applicable scope. Combined with the actual demands, a prototype system based on microwave transmission was designed to measure the water content of oil-tank sludge. Besides, proximate analysis of coal, membrane filtration method and subtraction method were introduced to measure the slag content and oil content, respectively.(2) Suitable microwave hardware components were chosen and a detection circuit was designed with the MSP430F149 microcontroller. A prototype system was constructed to measure the water content of oil-tank sludge, which can effectively reduce the stratification influence by the vertical transmission method. Experimental results showed that, the absolute error was less than 2% with the oil-tank sludge’s water content less than 30%. If the oil sludge’s water content was more than 30%, it can be mixed with pure oil to make its water content less than 30%, and then be detected.(3) The accuracies of proximate analysis of coal and membrane filtration method were investigated by related experiments. Experimental results showed that the ash determination method was not suitable for slag content measurement of oil-tank sludge. The absolute error of volatile matter determination method was less than 4%, and that of the membrane filtration method was less than 5%. Besides, the error sources of those two methods were analyzed, and some suggestions for improvement were given.