Some Fundamental Problems In The Process Of The Energetic Compound Preparation

Energetic compounds are a kind of special compounds which can self-decompose and rapidly release large amounts of energy without the presence of external substance. These features make them the key material bases for the development of advanced weapons. The synthetic processes of energetic compounds always involve nitration reactions, oxidation reactions, etc, which have a high reaction rate, a strongly exothermic effect, and a great thermal runaway potential. Thus, these processes require high performance reactors and good operation conditions. Moreover, the flammable and explosive products make it dangerous for post treatment. In the dissertation, related fundamental problems of the oxidation process of a certain energetic compound were studied. Related properties of the system involved in the process were determined. The heat transfer experiment was taken in a stirred tank reactor with a coil inside. Convective heat transfer coefficient correlations of the outer surface of the coil for different impellers were obtained and a proper type of impeller was selected for the strongly exothermic process. A stirred tank reactor with high heat transfer performance was designed with the help of engineering calculation and numerical simulation. The process was modeled and a solving software was developed for operation optimization and runaway situation simulation. Besides, a continuous crawler filtration equipment was developed for the filtration of energetic compounds. A mathematical model was established for the filtration process.The main contents are generalized as follows:1. Binary and ternary mixtures of dimethyl sulfoxide (DMSO) with ethanol and water are involved in some energetic compound synthetic processes. The thermal conductivities of DMSO+ethanol, DMSO+water and DMSO+ethanol+water at0.1MPa and temperatures ranging from (278.15to338.15) K covering a wide concentration range were determined and correlated for the optimization design of the energetic compound synthetic processes, as well as the densities of DMSO+ethanol+water.2. The impeller is the core component of a stirred tank reactor. In the dissertation, five types of impellers, including a2pitched blade turbine, a4pitched blade turbine, a propeller, a CBY impeller and a CBY-H impeller were chosen for the heat transfer experiments in a stirred tank reactor with a coil inside. The influence of impeller type and stirring speed on heat transfer performance of the coil was investigated. The convective heat transfer coefficient correlations of the outer surface of the coil were obtained, which are helpful to select a proper type of impeller for the stirred tank reactor during the design of energetic compound synthetic processes.3. The oxidation process design of a certain energetic compound was studied. The oxidation reaction is strongly exothermic and the large amount of hydrogen peroxide in the system can intensively decompose and cause an accident when it is overheated. Large quantities of coil rings are then needed. Since intensively arranged coil rings may lead to a poor flow and heat transfer performance of reactants in the reactor, computational fluid dynamics (CFD) was introduced to investigate the influence of coil clearance and fix height on the flow performance in the reactor. Based on the CFD simulation results, a proper design was determined. A mathematical model was then established for the oxidation process and a solving software was developed by Visual Basic (VB). The influence of feeding rate, reaction temperature and reaction time on the reaction process was investigated. Runaway situations were investigated as well. Then proper operation conditions for the process were determined. The prototype line built up according to the research results runs well.4. So far, the energetic compound filtration still relies on batch operation, which is labor-intensive, low efficient, and dangerous. A continuous crawler filtration equipment was developed based on the horizontal belt filter, and some improvements were made for safer, continuous and automated energetic compound filtration. A mathematical model was established and a software was developed for the simulation of the filtration.