In the food and chemical industry, the design of new process pipelines and modernization of existing pipeline systems for transportation of raw materials, semi-finished products and finished products is a complex organizational and technical task, one of the stages of which is to carry out the necessary hydraulic calculations. It is common practice in domestic and foreign practices to hydraulically calculate pipeline lines based on the flow intricacy equation and the Bernoulli equation for a real viscous liquid, which takes into account pressure losses on friction and on overcoming local pipeline resistances. With this approach, hydraulic calculation is a multivariate task, as there are infinite combinations of pipeline diameter - differential pressure parameters, unequal from both economic and technical positions. Based on the analysis of literary sources, the work shows the expediency of carrying out hydraulic calculation of pipeline lines according to techno-economic indicators. Total annual costs for creation and operation of the process pipeline, which are a linear superposition of capital and operating costs, are proposed as a criterion for technical and economic optimization of process pipelines. The work proposes design ratios for determining the optimum diameter of the process pipeline based on the condition of minimization of the total annual costs for its creation and operation taking into account the current prices and tariffs for the pipeline and electric power, routing of the pipeline, conditions of its operation, as well as properties of the transported medium. On the example of hydraulic plant for pumping of molasses, computational experiments were carried out to assess the influence of pipeline diameter and mass flow rate of transported medium on technical and economic indices of process pipeline and its optimal parameters were determined. In order to estimate the efficiency of optimization measures, the criterion is proposed, which allows to compare the total annual costs for creation and operation of process pipelines with optimal and different parameters.

process pipeline, techno-economic optimization, pressure loss, optimization criterion, hydraulic calculation

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