Study on the exothermic characteristics of backfill in the golf of Maoping Lead Zinc Mine

In order to study the hydration heat generation and temperature change characteristics of cemented backfill in Maoping lead zinc mine stope, based on the tailings and machine-made sand collected on site, eight backfill samples with different water cement ratio and different aggregate ratio are prepared by using the similar material experimental method. The temperature change curve of cemented backfill samples is measured in the laboratory, and then the hydration heat in the cementation process of backfill materials is calculated, finally the variation law of hydration heat and heat production of filling materials with time is analyzed. The results show that the filling sample shows an overall trend of rapid temperature rise in the early stage and then slow decline to the ambient temperature, and the variation of hydration heat production rate and temperature is related to the ratio of filling materials and ambient temperature. The main conclusions are as follows: the greater the proportion of machine-made sand and water cement ratio, the greater the heat production of filling material cementation, and increasing the tailings content of filling material can effectively reduce the heat production of filling hydration; the water content has the greatest impact on the heat production of the filling body, thus the most effective way to reduce the heat production of hydration is to reduce the water cement ratio, followed by increasing the tailings content in the aggregate, which provides a basis for selecting a reasonable filling body ratio in Maoping lead-zinc mine