What Is Sand Mining?

Sand mining boat is a floating mining and dressing combined device for mining underwater sand deposits or loose materials. The excavation mechanism installed on the poop bow is used to mine the ore and is lifted to the ship's silo. After being crushed, washed and classified by the simple screen, the fine-grained material under the sieve flows into the coarse chute or jig In the rough separation, the tailings are discharged to the goaf behind the stern through the tailings chute or sand pump, and the waste stones on the round screen are discharged to the tailings heap behind the stern through the belt conveyor or gravel chute. Since this floating device was originally used in New Zealand to mine placer gold, it was named the gold mining ship, and later it was also used to extract placer platinum, cassiterite, diamond, rutile, monazite, zircon, sulfur, phosphate, coal, silver , Ilmenite, silver-lead-zinc ore, iron sand, niobium, tantalum, hafnium and other minerals and construction sand and pebble. Any method of mining useful minerals by a sand mining ship is collectively referred to as sand mining, which is referred to as ship mining for short. ^[1]

There are two types of sand mining boats:

Generally speaking, for sand mining, the sandy uses are different and the mining methods are different. Multi-purpose sand suction

Sand mining boat mining method refers to the mining sequence of the sand mining boat on the working surface, also known as the mining method. Mining methods can be divided into two types: layered mining methods and trench mining methods. The sand mining method of the layered mining method extracts layer by layer from the top to the bottom of the working face until it reaches the bottom plate; the ship moves forward by one step and then layered from the top to the bottom. Its advantages are that the layer thickness of the excavation can be adjusted according to the properties of the soil and rock, it is easy to control the full bucket coefficient, the ore supply is uniformly conducive to the stable ore recovery rate, the average height of the soil and rock is small, and it is easy to operate and manage. According to the relative position of the ship's axis and the centerline of the working face and the width of the first mining face, the layered mining method can be divided into three types: positive and inclined full working face mining methods and half working face mining methods.

(1) Mining method of positive working face. The axis of the ship coincides with the centerline of the working surface, the angle of the ship's left and right movement is basically equal, and the tail gravel pile is located in the middle. The advantage of this method is that the full bucket coefficient is high and the load of the ship's transfer winch is uniform; the main disadvantage is that when mining thick sand ore bodies, tailings piles may appear on the side, increasing the depletion of the sand ore. And losses.

(2) Mining method of inclined working face. This is due to the shortcomings of the positive working face mining method. When the axis of the ship deviates from the centerline of the working face by a certain distance, the tailings pile can be deflected to one side, thereby avoiding pressure on the other side.

(3) Mining method in half working face. Think of a working surface roughly as the left and right halves, and then dig half of them from top to bottom, until the floor, and then the remaining half. Then the ship moves forward by one step and then turns back to mining. This method is applicable to the conditions where the soil and rock properties of the working face differ greatly, or the soil contains large gravel. The bucket chain or suction pipe rack of a sand mining ship with the trenching method is first lowered to a certain height at the bottom or middle of the mine, and along the horizontal trenching, the soil and rock in the upper part of the trench fall down, and then the collapsed soil and rock are recovered and the floor is cleaned. This method is suitable for mining old mining areas with tailing gravel piles, high dry gangs on the water or frozen surface ore.

The management of sand mining in the Yangtze River is a long-term and complicated water affairs activity. In recent years, Anhui Province has continued to increase its efforts, and its achievements cannot be ignored. The experience is precious, but illegal sand mining still occurs in some river sections. From time to time, sand dredging vessels have deviated from supervision, and the construction of sand dredging vessels is still widespread. It is still a long way to go to manage sand mining in the Yangtze River.

To deepen sand mining control in the Yangtze River, we must pay attention to system governance, law-based governance, comprehensive governance, and source governance. Focus on system governance, promote the transformation of government governance to government guidance and joint governance of all parties on the governance subject, further play the leading role of the government, guide the orderly participation of all parties in the society, strengthen the construction of the sand mining integrity system, and realize government governance and social self Benign interaction between regulation and industry autonomy; focus on governing according to law; in terms of governance, we must change from regulatory control to legal guarantee, and use the rule of law thinking and rule of law to continuously resolve contradictions in sand mining management; focus on comprehensive governance, and Change from a single method to a comprehensive use of multiple methods, strengthen moral constraints, change the shameful situation of stealing river sand, adjust interest relations, coordinate social relations, and solve problems in sand mining management; focus on source governance, and in the governance link It is necessary to engage in the shift from post-treatment to source control and advance, adhere to both the root cause and the root cause, and realize the source management of the sand mining boat and the entire process management of the sand mining behavior ^[2] .