防治煤自燃的感温控制释放型微胶囊化阻化剂研究

Spontaneous combustion of coal is a major hazard in coal mining. The existing inhibitors for this hazard still have some shortcomings, such as the short effective time and low inhibition effect. Trying to overcome these bottlenecks, a novel method based thermo-responsive controlled-release microcapsules of chemical inhibitor will be established in this project.. Based on our previous investigations, the key active groups that influence the development of coal self-heating and their reaction sequences have been revealed. And the applicant is trying to study the chemical ways for inhibiting the reactions of these reaction sequences. On this basis, the applicant will propose a novel efficient chemical inhibitor. Using the antioxidants and hydroxyl compounds, a high-effective chemical inhibitor which can restrain or cut off the reaction sequences of the key active groups will be invented to prevent the coal spontaneous combustion.. Then we will change the existing forms of the chemical inhibitor by the microencapsulation method. The thermo-sensitive polymers will be used as the shell material of microcapsule. The inhibitor microcapsules will have temperature-sensitive controlled-release characteristics. They will maintain as their original status until coal temperature reach a special range. Then the inhibitor materials in microcapsule core will release and react with the active groups in coal. This will inhibit the coal self-heating process and prevent the coal spontaneous combustion to occur. The release temperature and release rate can be controlled through changing the characteristics of shell material of microcapsule. During the applications, the inhibitor microcapsules will be sent to the coal self-ignition region in the flow of chemical inhibitor suspension. In response to the coal temperature and its changing trend, water, chemical inhibitors and the inhibitor microcapsules will realize the inhibition simultaneously or step-by-step, thus improving the inhibition efficiency and duration. . For more effective application of microencapsulated chemical inhibitor, the project will study the suspension characteristics of inhibitor microcapsules in different fluid carriers and their flowing characteristics. Then the best technical parameters will be selected, including the size distribution and additional quantity of inhibitor microcapsules, the rate and pressure of flow.. This study innovatively proposed a new thinking of inhibiting coal self-heating, through retarding reactions of active groups, which will provide key technology for more effective prevention of coal spontaneous combustion.

针对现有煤自燃阻化剂阻化寿命短、阻化率低等不足，提出研究一种抑制煤自燃关键活性基团反应的感温控制释放型微胶囊化阻化剂。在申请人前期研发单组分化学阻化剂的基础上，通过多剂联用、复配优化，研制基于抗氧化剂、功能性化合物和添加剂复配物的化学阻化剂，消除或抑制煤中关键活性结构及反应中间体实现煤自燃防治；并以温敏性聚合物为壁材对化学阻化剂进行微胶囊化处理制备阻化剂微胶囊，使之具备感温控制释放特性，常温下囊壁稳定但达到设定温度后破裂并释放出内部阻化剂发挥阻化作用，通过改变微胶囊化过程囊壁特性可控制释放起始温度和释放速率；使用过程中，以化学阻化剂水溶液为载体将阻化剂微胶囊输送至煤自燃区域，根据该区域温度状态，悬浮液中的水、化学阻化剂、阻化剂微胶囊可同步或逐级发挥阻化作用，从而提高阻化效率并延长阻化寿命。本项目创新性地提出了一种抑制活性基团反应的煤自燃阻化新思路，能够为高效治理煤自燃提供关键技术。

煤自燃是影响煤矿安全生产的主要灾害形式之一。除损毁煤炭资源外，煤自燃产生的有毒有害气体对人员身心健康构成严重威胁；一些条件下，甚至会导致瓦斯、煤尘爆炸等重特大恶性事故。此外，我国西北地区还存在大面积的煤田自燃火区，导致的煤炭损毁和环境破坏令人触目惊心。本项目针对现有煤自燃阻化剂阻化寿命短、阻化率低等不足，研究了一种抑制煤自燃关键活性基团反应的感温控制释放型微胶囊化阻化剂。在阐明影响煤自燃发展的关键活性基团及其反应模式并研发单组分化学阻化剂的基础上，通过多剂联用、复配优化等方式，研制了基于抗氧化剂、功能性化合物和添加剂复配物的复合型高效化学阻化剂，能够有效消除或抑制煤自燃发展过程中的关键活性结构及反应中间体，使煤自热化学反应链难以持续发展并强化进行，从而实现煤自燃的高效防治。在研制出煤自燃高效复合化学阻化剂的基础上，采用微胶囊化技术对阻化剂进行表面包覆处理，以温敏性聚合物为壁材对化学阻化剂进行微胶囊化处理制备阻化剂微胶囊，制备出的阻化剂微胶囊具备感温控制释放特性，常温下阻化剂微胶囊的囊壁较为稳定，但当微胶囊所在环境温度达到设定温度（该温度值可通过调整囊壁的温敏性材料成分进行改变）后，阻化剂微胶囊囊壁破裂并释放出内部的高效复合阻化剂芯材，从而与周围破碎煤体接触后发挥阻化作用。此外，通过改变微胶囊化过程囊壁特性可控制释放起始温度和释放速率，从而实现遗煤的长效阻化。在防治煤自燃的实际使用过程中，以化学阻化剂水溶液为载体将阻化剂微胶囊输送至煤自燃区域，通过感应注入区域周围的环境温度状态，阻化剂微胶囊悬浮液中的水、化学阻化剂、阻化剂微胶囊可同步或逐级发挥阻化作用，从而显著提高了阻化剂的阻化效率并延长阻化寿命。本项目创新性地提出了一种抑制活性基团反应的煤自燃的长效阻化新思路，为高效治理煤自燃提供了关键技术，对于煤自燃灾害的高效防治具有重要的理论意义和使用价值。