(1. School of Civil Engineering,Chongqing University,Chongqing 400045,China;2. Key Laboratory of New Technology for Construction of Cities in Mountain Area,Ministry of Education,Chongqing University,Chongqing 400045,China;3. School
of Civil Engineering and Architecture,Chongqing University of Science and Technology,Chongqing 401331,China)
Abstract:As industrial waste,electrolytic manganese residue (EMR) has small particle size and poor permeability,so traditional microbial mineralization technology has great limitations in the treatment of the EMR. In this paper,the curing technology with MgO and microbe is proposed,the EMR in Xiushan Chongqing was treated by active MgO and microbe,the principle of curing tailing sand with MgO and microbe was discussed,the effects of active MgO content on water content,unconfined compressive strength,acid-base,XRD pattern and microstructure of solidified samples were studied. The research results indicate that the active MgO reacts with water,fills the micropores of the EMR,and carbonizes with in the air,the strength of solidified samples was improved to a certain extent,and under the action of bacteria,urea was hydrolyzed to form ,which rapidly carbonized the hydration products and further improved the strength of solidified samples. The higher the content of active MgO,the lower the moisture content,the higher the unconfined compressive strength and the higher the pH value of solidified sample of the EMR. The main products of curing tailing sand with MgO and microbe are nesquehonite,dypingite and hydromagnesite. The larger the content of active MgO,the higher the content of nesquehonite.