All through the last decade, the Brazilian pipeline industry has invested heavily in controlling long pipeline’s inventory, leak detection systems and in energy efficiency, the latter being object of study of this paper. A sensitive area to such investments can be perceived in the efforts made to control the energy supply to pumping stations. Nevertheless, one can clearly observe the weight of tradition pending over Brazilian projects resulting in a tendency toward the use of control valves as means of pump controlling. This solution is generally believed to be simpler, more reliable and less costly than the common alternatives. Still and all, as the Brazilian pipeline industry modernizes its facilities and procedures, particularly due to economic and environmental concerns, new strategies for traditional problems are considered and assessed in engineering projects.

Throughout this paper, the authors assess one such project in which the engineering staff chose to apply a variable frequency drive (VFD) instead of the traditional process automated control valve. The company that operates the system made available the necessary process data and project parameters in order to conduct a thorough assessment both from the financial and the technical points of view. Hydraulic data as well as electrical motor parameters were made available to this research as well as a yearlong worth of process instrumentation data. Brazil has a long history investing and developing technology to replace gasoline for ethanol as automotive fuel. The pumps studied, located at the city of Ribeirão Preto, are responsible for pushing ethanol through a pipeline all the way to the Refinery of Paulínia, delivering fuel to be consumed in São Paulo’s metropolitan area, the most populated location in the country. As a basis of comparison, the authors estimated the capital and operational expenditure as well as the energy consumption of a fictional control valve system for the same pipeline and then put them against actual data made available by the company.

As a conclusion, the paper brings to light that, although variable frequency drive systems indeed demand a higher capital expenditure, when the operational costs are considered, they can compensate that initial investment by presenting the facility with more energy efficient operation. Furthermore, after carefully assessing the provided data, the variable frequency drive seems to result in a more continuous and smooth operation maintaining a higher occupation rate of the pipeline. Suggestions are also proposed and assessed as a guide to further investments and operational procedure changes aiming at optimizing the company’s process.

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