煤气化渣提炭分质是实现其减量化、资源化、高值化利用的关键。基于此,提出研磨破碎-气流分级的干法提炭工艺,利用研磨使气化渣中炭灰结合物解离,再利用气流分级机内离心力和气体曳力作用,将解离所得的细颗粒进行高效分离。通过设计均匀试验并对各影响因素进行回归分析,获取优选试验条件并对该试验条件下的提炭效果进行验证。结果表明,气流分级提炭受多因素耦合作用影响,其中分级机频率和引风机频率是影响提炭效果的关键。均匀试验优选条件为分级机频率175Hz、引风机频率5Hz,喂料螺旋频率5Hz,二次风口全开;该条件下所得富炭产品的收率为25.86%,烧失量49.76%,较原气化渣烧失量提高了26.91%,与试验预测值(49.64%)较一致,且试验效果明显优于未研磨破碎直接气流分级的气化渣。优选条件下气流分级得到的富炭产品的平均粒径(Dav)为5.95μm,满足橡胶补强填充料的粒度要求,其热值为16.73MJ/kg,亦可作为细粉燃料等使用。同时,气流分级可实现较好的气化渣脱炭效果,所得脱炭渣烧失量低于10%,有利于其在建材等领域应用。研磨破碎-气流分级方法可实现气化渣的提炭分质,有利于其下游利用。

slag. A large amount of carbon-ash complexes in the coal gasification slag formed under the conditions of high - temperature meltingand complex reaction atmosphere. Grinding is an important method to dissociate the residual carbon in the slag. However, the particle sizeof the grinded slag is too small to use conventional separation process to extract carbon. Air classifier can achieve efficient separation of ultrafine particles by utilizing the centrifugal force and aerodynamic drag of different particles in the vortex to generate different directionsof movement for classification. Based on this, a dry carbon extraction process by grinding the gasification slag was proposed and then theair classifier was used to separate residual carbon and ash. Through the design of uniform test and the regression analyses of the influencingfactors, the optimal experimental conditions were obtained and the experimental results were verified. The results show that the airflow classification is influenced by the coupling effect of multiple factors, among which the frequency of the classifier and the frequency ofthe induced draft fan are the key factors affecting the carbon extraction effect, the optimum experimental conditions were the frequency ofthe classifier 175 Hz, the frequency of the induced draft fan 5 Hz, the frequency of the feed screw 5 Hz, and the opening of the secondaryair valve 90°. The predicted value of the LOI of the carbon-rich products obtained under this condition (49.64%) is consistent with theexperimental results (49.76%);Under the optimal conditions, the D of the carbon rich product obtained by airflow classification is 5.95 μm,canbe used as a rubber reinforcement filler to replace carbon black and white carbon black; The calorific value is 16.73 MJ/ kg, which can befully used as fine powder fuel. Moreover, airflow classification can achieve good decarbonization effect of gasification slag, and the resulting decarburization slag has a loss on ignition of less than 10%, which is beneficial for its application in the field of building materials andother fields. The grinding crushing airflow classification method can achieve the separation of gasification slag, which is beneficial for itsdownstream utilization.

0 引言

1 试验原料和方法

   1.1 原料

   1.2 试验装置及方法

   1.3 分级产品性能评价

2 试验结果与分析

   2.1 均匀试验设计

   2.2 试验结果

   2.3 分级产品密度

   2.4 回归分析

   2.5 最佳试验条件验证

   2.6 优化条件所得产品性质分析

3 结论