As an important pharmaceutical intermediate product, niacin is widely used in the production process where dust explosions could occur if processed in powdered form. Aluminum hydroxide and aerosil are commonly used in the manufacturing process as pharmaceutical excipients. The effects of dust concentration and dispersed pressure on the lowest ignition temperature of niacin dust cloud were experimentally investigated. Results show that niacin dust has an optimal ignition concentration and the lowest ignition temperature basically remains unchanged and then increases with the dispersed pressure. Inerting experiments of niacin dust were conducted at different dust concentrations, dispersed pressures and the addition of inert dust. With inert dust of aluminum hydroxide, aerosil or mixed aluminum hydroxide-aerosil, the lowest ignition temperature increases with inert dust concentration, and the inhibition effectiveness increases in the order of aluminum hydroxide, aerosil and mixed aluminum hydroxide-aerosil. The synergistic inhibition effect of aluminum hydroxide and aerosil is efficient, and its inhibition mechanism is mainly manifested by thermal stability, diluting the oxygen, and as a third body which has passive influence on the combustion chemical kinetic reaction. This work provides reference for prevention and mitigation of accidental explosions during processing, storage and transportation in the industry of pharmaceuticals.

烟酸作为一种重要的医药中间体，广泛用于生产过程中，如果加工成粉末状，可能会发生粉尘爆炸。氢氧化铝和气硅通常用作制造过程中的药物赋形剂。试验研究了粉尘浓度和分散压力对烟酸粉尘云最低着火温度的影响。结果表明，烟酸粉尘具有最佳着火浓度，最低着火温度基本保持不变，然后随着分散压力的增加而增加。在不同的粉尘浓度、分散压力和惰性粉尘的加入下进行烟酸粉尘的惰化实验。含有氢氧化铝、气雾剂或混合氢氧化铝-气雾剂的惰性粉尘，最低着火温度随惰性粉尘浓度升高而升高，缓蚀效果按氢氧化铝、气雾剂和混合氢氧化铝-气雾剂的顺序增加。氢氧化铝和气硅的协同抑制作用是有效的，其抑制机制主要表现在热稳定性、稀释氧气、作为第三体对燃烧化学动力学反应产生被动影响。该工作为医药行业在加工、储存和运输过程中预防和减轻意外爆炸提供参考。氢氧化铝和气硅的协同抑制作用是有效的，其抑制机制主要表现在热稳定性、稀释氧气、作为第三体对燃烧化学动力学反应产生被动影响。该工作为医药行业在加工、储存和运输过程中预防和减轻意外爆炸提供参考。氢氧化铝和气硅的协同抑制作用是有效的，其抑制机制主要表现在热稳定性、稀释氧气、作为第三体对燃烧化学动力学反应产生被动影响。该工作为医药行业在加工、储存和运输过程中预防和减轻意外爆炸提供参考。