Study On Preparation And Performance Of Coal Seam Anti-collapse Agent

It is a urgent need technology that drill in CBM and coal seam in our current drilling rngineering, of which it is one of the difficulties that borehole instability problem of the large curvature segment of coal seam in the horizontal well drilling. Due to coal seam's hardness is small, brittle is large, cleat has developed, mechanical strengh is low, so it is easy to collapse, additional the suspending weight is big in the large curvature segment, it is more likely to sollapse when encourtering water, so that sticking and reaming, and even buried drilling tools, which lead to the borehole drilling engineering scrap, and which restrict rapid development of our CBM of drilling technology.This paper studies the physical and chemical properties and reservoir sensitivity of Baode Block. Baode Block's coal contains a certain amount of clay minerals (mainly kaolinite), silica and a large amount of organic matter. Therefore, it likely to migrate, and it possesses brittleness and hydration properties. It suffers water will swell, which will bring about wellbore instability. Thence, this paper presentate using aminate degradate polyvinyl alcohol complex with sulfonated asphalt as anti-sloughing agent.We can add different amount of hydrogen peroxide dosage into the reaetion container in some kindtemperature and pressure, to aminate the degradate product.Finally, we can get aminate degradate polyvinyl alcohol.We can get specific solution with its pH of that approximately at9, with a tempreture range of 80-90?.Degraded rawmaterials with set degree of Polymerization are obtained through such operation followed by amination reaction with diethylamineas aminate reagent. Optimization of degradation and aminate conditions are achieved by variance methord and a good performance of new aminate anti-sloughing agent is synthesized under certain kind of experimental conditions. The optimum condions were as follows: the adding volume of concentrated hydrochloric acid is 1.5ml under the premise of adding amount of cationic reagent 1.5ml, the reaction temperature is 80?. the reaction time is around 2.5h. At last, aminate degradate polyvinyl alcohol complex with sulfonated asphaltproportion is 1:2. Therecovery rateof product got finally can reatch 84.63%...