化工企业生产计划优化中非线性单耗的建模方法

化工过程生产装置的原料单耗与生产负荷呈明显的非线性关系。为了得到更切合实际的化工企业生产计划优化结果，采用分段线性函数和多项式函数对非线性单耗问题建模并进行比较。案例结果表明，分段线性函数不需要回归参数，建模简单，精度较高，对于中等规模问题求解时间短，能够同时处理装置的多种原料非线性单耗，而不需要增加新的整数变量，多项式函数则不具有这些优点。分段线性函数建模方法已经在化工企业生产计划图形建模优化系统(GIOCIMS)中实现，并在中国石化巴陵分公司得到应用。

Approaches to modeling nonlinear unit consumptions in optimal production planning of chemical enterprises

Unit consumptions of raw materials reveal distinctly a nonlinear relationship vs unit loads in chemical processes.To obtain more practically optimal solutions for production planning in chemical enterprises, piecewise linear function and polynomial function were used to model nonlinear unit consumptions.The optimal solutions obtained by the two approaches were compared in case studies.The results indicated that the piecewise linear function approach was easy to model nonlinear unit consumptions with a higher accuracy without regressing any parameter, and the related model could be solved quickly for a medium size problem.Meanwhile, the piecewise linear function approach could simultaneously handle nonlinearities of multi raw materials in a unit without adding any new integer variable.Comparatively, the quadratic function approach was lack of these advantages.The piecewise linear function approach has been implemented in the graphical modeling system for optimal production planning of chemical companies (GIOCIMS), and the system is used in Baling Branch Company Sinopec.