Method for jointly treating acid mine wastewater by using organic matter and carbonate rock

Abstract

The invention discloses a method for jointly treating acid mine wastewater by using organic matter and carbonate rock. A first-stage pretreatment area (1) is a container which is divided into left and right parts, the bottoms of the left and right parts are communicated, one side of the container is filled with organic matter filler, and the other side of the container is filled with carbonate rock filler; wastewater firstly contacts with the organic matter, the principle that the growth of aerobic microorganisms needs to consume dissolved oxygen is used, so after acid mine wastewater passes through the organic matter, the dissolved oxygen in the wastewater is removed, and an oxygen-free condition is formed; the carbonate rock is used to adjust pH under the oxygen-free condition, so the voids of the filler can be prevented from being blocked by the Fe(OH)3flocs rapidly generated in a reaction area; water flows from the first-stage pretreatment area (1) to enter multistage tandem reaction areas (2), each reaction area (2) is the same as the first-stage pretreatment area (1) in the structure and the contents, wastewater is re-aerated in the process that the wastewater enters a sedimentation tank from the carbonate rock reaction area through a natural drop way. The method is good in effect, low in investment and low in the cost of wastewater treatment.

Description

technical field [0001] The invention belongs to the technical field of wastewater treatment, and in particular relates to a method for treating acid wastewater. Background technique [0002] Coal, as one of the most important energy sources, has produced a series of environmental problems along with the massive mining of coal. Among them, acid coal mine wastewater (AMD) is a prominent environmental problem. AMD has the characteristics of low pH value, high salinity and strong corrosion, and carries a large amount of heavy metal elements and harmful chemicals, causing local water, soil environment and environmental pollution. The ecosystem has been severely damaged. A large number of abandoned small coal mines (mines) are large in number and widely distributed, and mine drainage usually has a small flow rate, a low pH value (about 2 to 3), AMD pollution for a long time, and difficult treatment, which has a serious impact on the environment and humans. [0003] At present, t...

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Problems solved by technology

As a simple and reliable method, the neutralization method is widely used in the treatment of AMD, but the consumption of a large amount of neutralization reagent will generate a large amount of sludge, which is easy to cause secondary pollution to the environment; the sulfide precipitation method has a good removal effect, However, the pH value is difficult to control, the sulfide precipitant is more expensive, and the treatment cost is high; the artificial wetland method is widely used in some developed countries to treat acid mine drainage. This method has low investment, low operating cost, and convenient management, but it occupies a large area , is obviously affected by environmental factors. When the acidity is high, the improved wetland method has certain limitations in the treatment of AMD.

For this reason, people are constantly improving and exploring the treatment method of acidic wastewater from mines. Chinese Patent Publication No. CN1618742 on May 25, 2005 disclosed a "method for the source treatment of acidic wastewater from non-ferrous metal mines". The waste that produces in the mine beneficiation process is treated with waste, but this method has certain limitations for non-ferrous metal mines; Chinese Patent Publication No. CN1508079 on June 30, 2004 disclosed a kind of "preventing mine from producing acidic wastewater The method ", using lime milk to carry out saturated spraying around the mine, and laying waterproof materials on its surface, this method can control mine wastewater from the source, but it is difficult to implement, and there are certain risks; Chinese Patent Publication No. CN1418831 was published in 2003 On May 21, "a method for treating non-ferrous metal acidic wastewater" was disclosed. The method is one-stage lime neutralization plus two-stage polyferric sulfate precipitation to treat non-ferrous metal acidic wastewater. This method has a large amount of sludge and is prone to produce secondary secondary pollution

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