Neutralizing agent for acidic mine water treatment in Zhaotong region and preparation method thereof

Abstract

The invention relates to a neutralizing agent for acidic mine water treatment in a Zhaotong region and a preparation method thereof. The neutralizing agent substitutes materials commonly used in traditional acidic mine water treatment, such as limestone, lime, lime, fly ash, and the like, provides a new path for the neutralizing treatment of acidic mine water in the Zhaotong region and similar regions and comprises permian dolomitic limestone maokouan. In practical use, the neutralizing agent has the optimal granularity smaller than 0.1 mm; the acidic mine water is firstly and preliminary precipitated and homogenated; and the neutralizing agent is added to the mine water and uniformly stirred. On the premise that the optimal granularity and the right treatment method of the neutralizing agent are ensured, a relation between the addition of the neutralizing agent and the addition of a mine water pH value satisfies a formula: Y=0.3783*X+1.1296 (Y is the addition of the mine water pH value, and X is the use amount of the neutralizing agent (kg / m<3>)); and the acidic mine water with a pH value of 2.0-3.0 can achieve a pH value of 7.0-8.0 after the addition and the right treatment of asuitable amount of neutralizing agent. The neutralizing agent has easy obtainment, converting preparation, simple use process, strong practicality and easy popularization without additional investment.

Description

technical field [0001] The invention relates to a neutralizer used for the discharge treatment of acidic mine water in coal mines and a preparation method thereof. More specifically, the present invention relates to a neutralizing agent for purifying acidic mine water discharged from coal mines in Zhaotong area and a preparation method thereof. Background technique [0002] Zhaotong area is an important coal-producing area in southern my country and Yunnan Province, with coal reserves of 16.582 billion tons and proven reserves of 10.227 billion tons. It is an important anthracite producing area in southern China and the second largest coal field in southern my country. The pH value of mine water discharged from most coal mines in Zhaotong is generally less than 3.0, and the total acidity is relatively high. This kind of strongly acidic mine water not only easily corrodes mine equipment and drainage pipelines, endangers the health of workers, but also causes serious pollutio...

AI Technical Summary

Problems solved by technology

However, using limestone as a neutralizing agent often makes it difficult for the PH value of the treated water to meet the discharge standards stipulated by the state, and the removal efficiency of iron is low, and the acidic mine water after treatment is also more precipitated, and in order to achieve better results , often also add a certain amount of CaO or Ca(OH) 2 , carbide slag, etc., which makes the working environment worse, so many mine water treatment stations that were originally designed to use limestone as a neutralizing agent, now most of them have switched to lime as a neutralizing agent

However, the treatment process using lime as a neutralizing agent has high cost per ton of water treatment, low utilization rate of lime, difficult settlement of neutralized products, large amount of pollution and difficulty in utilization, and poor operating environment for workers.

The conventional milk of lime neutralization treatment method has many restrictions. If the reaction is not complete, it is easy to cause secondary pollution. From the practical application effect, the milk of lime neutralization method is only suitable for the treatment of acidic mine water with a small water inflow.

In addition, some studies believe that the use of fly ash to treat acidic wastewater is also effective, but the amount of use is large, and the sedimentation load is large, so it is difficult to popularize and apply in practice.

Although caustic soda is used as a neutralizing agent in a small amount and generates less sludge, it tends to increase the total hardness of the treated water, and the cost is high, so it is basically not used now.

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