摘要
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175 Hz、引风机频率5 Hz,喂料螺旋频率5 Hz,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16.73 MJ/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。
The extraction and separation of residual carbon from coal gasification slag is the key to realize utilization of coal gasification slag.A large amount of carbon-ash complexes in the coal gasification slag formed under the conditions of high-temperature melting and complex reaction atmosphere.Grinding is an important method to dissociate the residual carbon in the slag.However,the particle size of the grinded slag is too small to use conventional separation process to extract carbon.Air classifier can achieve efficient separation of ul-trafine particles by utilizing the centrifugal force and aerodynamic drag of different particles in the vortex to generate different directions of movement for classification.Based on this,a dry carbon extraction process by grinding the gasification slag was proposed and then the air classifier was used to separate residual carbon and ash.Through the design of uniform test and the regression analyses of the influencing factors,the optimal experimental conditions were obtained and the experimental results were verified.The results show that the air-flow classification is influenced by the coupling effect of multiple factors,among which the frequency of the classifier and the frequency of the induced draft fan are the key factors affecting the carbon extraction effect,the optimum experimental conditions were the frequency of the 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 secondary air valve 90°.The predicted value of the LOI of the carbon-rich products obtained under this condition(49.64%)is consistent with the experimental results(49.76%);Under the optimal conditions,the Dav of the carbon rich product obtained by airflow classification is 5.95μm,can be used as a rubber reinforcement filler to replace carbon black and white carbon black;The calorific value is 16.73 MJ/kg,which can be fully used as fine powder fuel.Moreover,airflow classification can achieve good decarbonization effect of gasification sla
作者
杨凯
张乾
栾春晖
彭泽宇
黄伟
YANG Kai;ZHANG Qian;LUAN Chunhui;PENG Zeyu;HUANG Wei(State Key Laboratory of Clean and Efficient Coal Utilization,Taiyuan University of Technology,Taiyuan030024,China;College of Chemistry,Taiyuan University of Technology,Taiyuan030024,China)
出处
《洁净煤技术》
CAS
CSCD
北大核心
2024年第7期30-38,共9页
Clean Coal Technology
基金
国家重点研发计划资助项目(2020YFB0606304)。
关键词
煤气化渣
破碎
气流分级
分离
均匀试验
废物处理
coal gasification slag
crushing
airflow classification
separation
uniform test
waste treatment
