| For a long time,with the rapid development of China’s petrochemical,national defense industry,and social economy,the demand for hazardous chemicals has maintained a rising trend,and the railway transportation plays an important role in medium and long distance transportation of dangerous goods.In recent years,although the growth trend of the volume of dangerous goods has slowed down due to the influence of the COVID-19 epidemic,the requirements for the safety of dangerous goods of railway transportation have not been reduced.Furthermore,in the transportation of hazardous goods,the third category of flammable liquids have the largest transportation volume,which are unstable in nature and have a very high risk factor.Therefore,it is necessary to conduct an in-deep research particularly for the railway transportation of flammable liquids.The paper analyzes the current situation of hazardous goods transportation risk and transportation routes at home and abroad,points out the importance of optimizing the railway transportation routes for flammable liquids,and summarizes the three factors affecting the optimization of flammable liquids transportation routes.The bi-objective nonlinear integer programming model for minimizing transportation risk and cost is used to solve by using NSGA-Ⅱ algorithm,and a simple example is also used to verify the applicability of the model and the validity of the algorithm.Finally,the model and algorithm are applied to solve the problem of transporting gasoline tankers from the West of Urumqi Station to the East of Lianyungang Station,and optimal routes are determined for the railway hazardous goods carrier.The main contents of this paper are:(1)Clarify the definition and classification of flammable liquids and sort out the special conditions of railway transportation flammable liquids according to the "Management Rules for Railway Transportation of dangerous goods"(TG/HY 105-2017)(Railway Transportation[2017] No.164),"Classification and code of dangerous goods"(GB6944),and "List of dangerous goods"(GB12268)and other standardized documents,including its loading tools,packaging requirements,equipment and facilities,etc.Three factors affecting the decision-making of flammable liquids railway transportation pathway are summarized.(2)Quantitative representation of the risk of flammable liquids transportation.The accident rate of leakage is calculated using statistical and probabilistic methods,and the consequences of accidents are simulated using ALOHA software for common flammable liquids.Internal influencing factors are used to perform simulation analysis,obtain the spread of common flammable liquids,and then integrate the diffusion distance(accident radius)into the quantitative representation of the accident consequences,and the three aspects of personnel,equipment and environment are detailed.The consequences of accidents are delineated to pave the way for construction of the railway transportation risk model.(3)From the perspective of flammable liquids as the object of study,the transportation risk(personnel,environmental,and equipment risk)and transportation costs(distance and time costs)are minimized as the optimization objectives from the perspective of railway hazardous goods carrier.Based on the characteristics of the model and the comparative analysis of the existing transport diameter solution,then the NSGA-II algorithm is designed to solve the model.At last,an example is given to verify the effectiveness of the model and NSGA-II algorithm.(4)Using the route optimization model and NSGA-II algorithm to solve the actual transportation problem,and the minimum pathway of transportation risk and cost is determined according to the operation results.Besides,the sub-optimal pathway between minimum transportation risk and cost is also determined.The sensitivity of transportation risks and costs is analyzed from three aspects of the volume of installation,the number of leaking vehicles,and the time limit of transportation. |
PDF Full Text Request