Research On The Application Of Foamed Cement In Sealing Coal Mine Gas Drainage Holes

In recent years, mine gas drainage hole plugging method are becoming more and more mature, foamed polymeric material sealing because of its simple process, reliable sealing, sealing quickly and so has been widely applied, polyurethane material is currently using most of the polymeric material. However, due to the high cost of polyurethane and high operation requirements, limiting its broader development. Foam cement used as the drainage hole blocking material is a new direction on the sealing technology. It uses portland cement and sulfur aluminate cement as cementitious materials, with hydrogen peroxide as foaming agent, adding suitable amount of curing agent, water reducing agent and foam stabilizing agent admixture,etc, complete foaming reaction under atmosphere pressure, fully filling blocking drainage hole and the surrounding pore, condensation curing in 6 to 8 minutes, can achieve the desired effect. Because of its low cost, simple construction, is expected to replace the polyurethane polymeric materials widely used as mine gas drainage hole blocking material. The main work is as follows:1. Experimental study of foaming at room temperature: By adding water heat activator in powder materials, instead of warm water foaming requirements to achieve the purpose of the foam at room temperature. Studied the relationship between activator, water temperature and foaming rate, foam volume, to determine at different outdoor temperature conditions,the appropriate mix content of the activator.2.Volume stability optimization: Studied the principles of bubbles to grow and stable curing in the foaming process; Studied the relationship of pH, sulfur cement and mixing time on the stability of volume,it is concluded that the key influence the foam stability is balanced foaming rate and cure rate.3. Foamed cement solidification time optimization: As much as possible in order to minimize the setting time of foamed cement, carried out cement complex tests and orthogonal experiment of cement admixtures and water feed ratio.4. Foamed cement slurry flow study: Under the conditions of a fixed ratio of water to study the effects of water-reducing agent and silica fume on slurry flow, find out the suitable mixing proportion of the two.