Study On Aqueous Solution Of Ammonium Nitrate Thermal Safety Test System

In general, ammonium nitrate is stable and safe, but with temperature increasing, as well as impurities participation, ammonium nitrate will decompose and release heat, resulting in the burning or explosion. In view of the risk of ammonium nitrate a great deal of researches has been done at home and abroad. However, studies on the critical detonation temperature of ammonium nitrate in aqueous solution have been rarely reported.In this paper, thermal explosion theory is applied to study the thermal safety of ammonium nitrate in aqueous solution, and design a set of detonation temperature test. The whole is divided into two parts. The first part is the design of explosive vessel which is mainly used to test the critical explosion temperature of ammonium nitrate in aqueous solution. The second part is the design of the test device. Guided by the thermal explosion, according to the theory that largest vessel charged with mass fraction of 80% aqueous solution of ammonium nitrate 10ml and design vessel volume ofΦ23mm×57mm. First of all ,the research has confirmed that the form of the vessel is the material steal of 1616MnR , followed by the incident shock wave pressure vessel is calculate by using the relevant formula so as to arrive at the equivalent static load is 36.9 MPa, the design pressure is determined to 45Mpa. Lastly the design temperature of the container is defined to 350℃.On the basis of the above data, the explosive vessel wall thickness calculations, stress analysis, strength check as well as the design and calculations of discharge bursting disc device are all carried out. Via calculating the explosive vessel wall thickness is 20mm, the design pressure 40MPa, the flange thickness 22mm, head thickness 26mm, bolt diameter 6mm, and the burst pressure of rupture disc 39.6 MPa. On the basis of these calculated explosive vessel data, the heat set size ofΦ170mm×140mm .E-type thermocouple and TD7—RB10temperature controller are selected in accordance with experimental conditions. In addition, the security box is design in accordance with experimental conditions.Processing map will be drawn by AUTOCAD and airtight checks will be carried out until good gastight device is attained. Mass fraction of 80%aqueous solution of ammonium nitrate 10ml will be added to debugged device to measure the temperature of thermal explosion. Many occasions on 10ml 80% aqueous solution of ammonium nitrate come to the determination of the explosive temperature between 239℃and 241℃. In this paper, the range of explosive temperature of ammonium nitrate in aqueous solution is very close to decomposition characteristics of ammonium nitrate at temperature of 210 ~ 260℃which had been done studied by references.So as to arrive at the design of this test system have good performance.In this paper , this test system can not only be used to study the hot safety test system of ammonium nitrate in aqueous solution, at the same time it is with an important practical value in safe production of fertilizers.