微波照射下火成岩升温特性和升温预测模型研究

Study on Heating Characteristics and Prediction Model of Igneous Rock under Microwave Irradiation

微波辅助破岩可有效降低刀具磨损,提高破岩效率,具有广阔的发展前景。文章选取了10种火成岩进行微波加热试验,发现岩石的升温速率主要与岩石所含矿物的种类、含量,及岩石中的Fe元素含量有关。岩石所含矿物越敏感、含量越多,岩石中的Fe元素含量越大时,其升温速率越高。整体而言,火成岩中基性岩的升温速率最高、中性岩次之、酸性岩最低,该现象与火成岩的矿物和元素组成规律有关。在试验研究的基础上,文章提出了岩石升温预测模型。该模型除考虑了矿物种类和含量的影响外,还考虑了与升温有关的比例修正系数和结构修正系数。在升温预测模型中,敏感矿物升温的比例修正系数大于1,且随含量的增加而降低,最终趋向于1;非敏感矿物升温的比例修正系数小于1,且随含量的增加而增加,最终也趋向于1。同等条件下,块体的升温速率是粉末的2~3倍,且基性岩升温的结构修正系数大于中性岩和酸性岩。

Microwave-assisted rock breaking can effectively reduce cutting tool wear and improve breaking efficiency,which has a broad prospect of engineering development.10 kinds of igneous rocks were heated under microwave irradiation.The results illustrated that the heating rate depends on mineral species and content as well as the Fe content.The heating rate is higher when the rock contains more sensitive minerals and Fe.Generally,basic rock has the highest heating rate,followed by intermediate rock,acid rock the lowest.This phenomenon is related with the law of mineral and element composition in igneous rocks.Heating prediction model of rock was proposed based on experimental study.Except for mineral species and content,ratio and structure correction coefficients related to the temperature increment were also taken into consideration.In the heating prediction model,the ratio correction coefficient of sensitive mineral is bigger than 1,decreasing with the rise of its content,and eventually tending to 1.The ratio correction coefficient of non-sensitive mineral is smaller than 1,increasing with the rise of its content,and eventually tending to 1.The heating rate of block is twice to three times that of powder.The structure correction coefficient of basic rock is bigger than that of intermediate rock and acid rock.