Research On The Ecological Reconstruction Technologies Of Spontaneous Combustion Coal Gangue Heap

The coal industries in Shanxi,the province with rich coal resources,have been using the refuse discharging technology widely among their history.However,the gangue heaps created by this technology have a high risk of spontaneous combustions,which poses a great threat to eco-environment.To solve this problem,case studies of coal gangue heaps in Tunlan mine,Xiqu mine and Hedong mine have been conducted to discover the mechanism of extinguishment and after-combustion preventing,slope shaping and vegetation restoration by using the technology of entitative engineering implementation and practical construction,and employing the quantitative and qualitative research methods.The results show us the patterns of systematic fire extinguishing,multistage separated-slopes reversed-platforms and vegetation succession management and protection.According to this,an integrated technology of ecosystem reconstruction for spontaneous combustion coal gangue heaps has been developed.(1)Systematic extinguishing and preventing after-combustion technology:In order to have a deep understanding of fire behavior towards Tunlan mine coal gangue and put foward the corresponding technology of extinguishing and preventing after-combustion,a systemic extinguishing model was established,which gives a clear explanation to the mechanism of spontaneous combustion and high temperature region’s horizontal and vertical structure.Furthermore,it showed that the key to extinguishing was preventing the entrance of ventilation and moisture.Therefore,according to the different fire regime characteristics,the corresponding fire extinguishing system integration technology together with slope toe and slope closed preventing after-combustion technologies were applied into extinguishment.(2)Multistage Separated-slopes and Reversed-platforms stabilizating technology:As is known to everyone,the resonable heap shaping is helpful to consolidate the effect of fire extinguishing and the later vegetation restoration.Therefore,through a series of data contrastive analysis,the theoretic model of coal gangue multistage separated-slopes and reversed-platforms stabilizing technology was proposed and then applied into practical construction of coal gangue on mount Nan-Ping,which is proved to have sound effect.According to the actual situation,the length of separated-slopes is set to about 10m,width of reversed-platforms is about 2.5m,and additionally a series of supporting facilities like drainage and water-storage system,flexible slope toes,microrelief,loess-gangue mix as well as revegetation were employed in the project.(3)Technology of near-natural ecological reconstructionunder artificial promotion:On the basis of Near-natural concept,artificial interferences measures,as well as the key ecological factors effecting vegetation restoration,the author put forward a set of vegetation succession management and protection pattern in order to achieve the short-term rapid vegetation succession.Through different degrees of water management and cutting herb and shrub,vegetation succession can speed up and vegetation will be formed into tree,shrub and herb system in three to five years and gradually into forest after five years.This research has built a reconstruction and administration pattern for the ecosystem of spontaneous combustion coal gangue heap by integrating three technologies.Both practical and theoretical adaptation of this pattern was testified,as well as its effectiveness.And the experience recorded in this research may provide something valuable for similar cases studies.