Abstract: Reclaimed water is the non-drinking water that can be reused within a certain range after sewage treatment to a certain standard, and its water quality is between the tap-water and the effluent. To investigate whether the reclaimed water obtained from a certain sewage treatment plant in Zhuneng can be used as production water for coal preparation plants, methods such as titration and electrode analysis were used to detect and analyze water quality indicators such as hardness and pH value of the reclaimed water. It shows that reclaimed water can be used as equipment cooling water and production water for coal preparation plants (except for flotation) from the perspective of water quality alone. By comparing the flocculation and sedimentation experiments of coal slurry water under two water quality conditions, there was no significant difference in the flocculation and sedimentation rates of coal slurry water under different dosage conditions. Moreover, under the same water quality conditions, the flocculation and sedimentation rates of the five groups of coal slurry water showed a pattern of 3>1>5 g/m³. When the unit consumption of flocculant is 1 g/m³, the turbidity value of the supernatant after flocculation and sedimentation in the middle water group is the lowest. When the concentration of the drug is 3 g/m³, the coal slurry water is in a state of supersaturation of the flocculant. Although there is a relatively high settling rate, the excess flocculant is suspended in the supernatant, resulting in a higher turbidity value of the supernatant after settling. Based on water quality analysis data, coagulation and sedimentation test data, and stability evaluation analysis of coal slurry water samples prepared from two types of water, it is found that the hardness, pH value, and anionic surfactant content of reclaimed water are the reasons for the better coagulation and sedimentation effect of coal slurry water in reclaimed water environment. This demonstrates the feasibility of using reclaimed water as production water in coal slurry water treatment in coal preparation plants and has practical significance for solving reclaimed water treatment problems.