This paper presents a mathematical model , simulating program and results ofball pulverlzed coal storage system. The program of simulation is writen with ACSL language. theGear arithmetics to solve the differentlal equations is recom merded by MMS. The model has beenmodularized according to the reguirements of MMS. This modular called DTM modular can be con-sidered as one component of MMS modular library.