Research On Optimization Operation Technology For Crude Oil Storage And Transportation System

Crude oil storage and transportation system is the key link to the overall oilfield production. This large and complex system, not only a broad area, but also a complex and varied dynamic system. The main goal in scheduling decisions of crude oil transportation system is security, economy, smooth operation, while storage and transportation system implement oil transportation plan. At present, the optimization theory and method have been widely used in the research on optimal operation for the complex product system. Based on heat transfer theory, operational research and optimization theory, the research on optimization operation technology for crude oil storage and transportation system has a great advantage for improving the level of production scheduling, reducing the running cost as well as enriching the theoretical research achievement for the fields of engineering thermophysics and applied mathematics. Therefore, Daqing oilfield is taken as the research target, the following contents has been investigated:First of all, take the large floating roof oil storage tank and pipeline as research object, key hydraulic and thermodynamic processes in the process of storage and transportation of crude oil are analyzed. Including the following contents: a system is developed for monitoring the temperature distribution of oil in large floating roof tanks, and optimized the arrangement of temperature monitoring points.Using temperature monitoring system to monitor oil temperature distribution of 50,000m3, 100,000m3 and 150,000m3 dual-deck floating roof tanks, determine the oil temperature distribution characteristics. The heat transfer coefficients for different kinds of oil tank in different working conditions were calculated with the theory of heat transfer. Based on the principle of energy conservation, the prediction model of the average temperature and temperature field variation of the oil tank is established. For the hydraulic and thermal characteristics of oil pipeline, using inverse algorithm and optimal fitting method, the hydraulic and thermodynamic calculation model of oil pipeline is established based on the statistical analysis of the actual operation data. So that the relative error of hydraulic calculation is reduced to less than 12%, thermodynamic calculation error is reduced to less than 8%. In addition, the optimization fitting technique is used to fit the operating characteristics of the oil pump and the heating furnace in the storage and transportation system.Based on the analysis of hydraulic and thermodynamic process of storage and transportation system, the scheduling process storage and transportation system is decomposed into four basic process: oil depot loading, oil depot uploading, oil depot exportation and oil depot total exportation. Using tree structure, the data storage structure of binary chained list and the binary tree traversal methods to achieve the simulation of production scheduling process in storage and transportation system.Secondly, taking the different depots, long-distance pipelines and a whole scheduling process of storage and transportation system as research object, The production scheduling optimization model of Single stations and tank farms, the operation scheduling optimization model of long distance pipeline and the coordinated scheduling process optimization mathematical model of multi-station and tank farms were established respectively. It constitutes a crude oil storage and transportation system production scheduling optimization system.Based on the structural characteristics of production scheduling optimization model for Single stations and tank farms, establish a genetic algorithm including matrix coding, alone point crossing and relative prohibition selection strategy. Compared to the original scheme, applying this algorithm to optimize the operation schemes of different conditions in summer and winter of Daqing first of south oil depot enable the scheduling costs of oil depot reduce by 7.6% and 11.9%.Combining genetic algorithm and penalty function method, a hierarchical optimization method for the optimization of operation scheme of long distance transportation pipeline is established. Applying this solution to optimize the operation schemes of "Daqing-Harbin" long distance pipeline determine the optimum operating parameters and device combination of different oil transportation stations and enable the fuel and power costs of pipeline significantly reduced by 15.1%.The paper proposed to use hierarchical optimization solution combined with genetic algorithm and sequential quadratic programming method to solve the coordinated scheduling process optimization problem of multi-station and tank farms. Using the algorithm to optimize the scheduling scheme of oil export system which consists of Daqing first of south oil depot, third of south oil depot and north oil depot. The results show that it will allow the total oil scheduling costs of storage system reduce 9.1% by optimizing the loading and uploading oil operating modes of tank, oil depots exportation temperature and temperature-keeping temperature of different station and tank farms.Finally, based on C ++ Builder 6.0 application development platform and Microsoft Access database development tool, the theoretical research results are given to the computer and developed the "Daqing Oilfield storage and transportation scheduling process simulation and intelligent decision-making system." The system includes 8 functional modules: engineering project management, data management, graphics processing, simulation decision-making of depot operation scheme, scheduling assistant decision-making of storage and transportation system, emergency condition simulation decision-making, Daqing-Harbin pipeline optimization and tools, the simulation of production scheduling process and the optimization of scheduling scheme can be achieved.