| Coal which about seventy percent of primary energy production and consumption relies on, is the foundational energy in China. And the electricity coal accounts for more than half the total consumption. It is the coal used for generating electricity in power plants. The characteristics of Chinese coal resource distribution, productivity and energy structure determine that coastal transportation of the electricity coal plays an important role in "transport coal from north to south" and "sea-rail combined transport". With the improvement of the coal marketization and the change of characteristics of coal demand, power generation companies have formed an industrial pattern that integrates coal production, inventory and transportation. Under which, it is therefore highly significant to research coal’s maritime inventory-routing to meet the electricity coal demand of costal power plants and reduce logistics costs.This thesis summarizes and analyzes the marine inventory-routing problem systematically, combining the existing characteristics of the shipping and stocking electricity coal. It constructs a space-time network model with the objective to minimize total cost of the electricity coal’s maritime inventory-routing, aiming to meet the power plants’coal demand and capacity. It determines the electricity coal’s supplement time, supplement amount, the loading port, ship deployment and the routes for every ship, etc. Then, according to the characteristics of the model, it puts forward a corresponding algorithm to transform and decompose the problem. The algorithm chosen is simulated annealing algorithm, it is used to solve key steps in deploying ships and ship routing problem. At last, a case study of some power generation company’s coal maritime inventory-routing problem is carried out, and it is solved by the chosen algorithm. The total cost reduced by 9.9%, from 16121 thousand yuan to 14527 thousand yuan, and the results have verified the feasibility of the model and algorithm this thesis puts forward. |
