A low energy consumption sewage treatment process and system

Abstract

The invention relates to the technical field of wastewater treatment, in particular to a low-energy-consumption wastewater treatment technique and system. The technique comprises the steps of 1) coagulating and precipitating aluminum-bearing wastewater to obtain aluminum-bearing sludge; 2) crushing or homogenizing the aluminum-bearing sludge, and conveying to a reactor; 3) adding concentrated sulfuric acid and aluminum-bearing waste acid into the reactor, turning on a stirrer of the reactor, carrying out stirring for 30 min, observing PH value of a mixture in the reactor, adding aluminum-bearing waste acid or mold washing wastewater to adjust the PH of the mixture stably to 0.6-0.8, stopping stirring when the reaction temperature of the mixture drops to 40 DEG C, and allowing standing for4 hours. Sludge and waste alkaline liquids (mold washing waste alkali, aluminum-bearing waste acid, waste aluminum chips and the like) occurred in the treatment process of wastewater from aluminum processing industry are used as raw materials to produce a water purifier, aluminum sulfate; wastewater recycling rate is increased.

Description

technical field [0001] The invention relates to the technical field of sewage treatment, in particular to a low energy consumption sewage treatment process and system. Background technique [0002] In the production process of aluminum processing enterprises, there will be a large amount of waste water and sewage formed by waste acid. If the sewage is discharged directly, it will not only pollute the environment, but also waste a lot of resources. The existing technology will treat sewage to a certain extent and then discharge it, but the existing sewage treatment process has defects such as high energy consumption, non-recyclable products or low recycling rate of products, incomplete sewage treatment, and single raw materials for sewage treatment. [0003] Specifically: 1. In the prior art, sulfuric acid or waste sulfuric acid is added first and then aluminum-containing sludge is added in the feeding process. The disadvantage is that the aluminum-containing sludge is easily...

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Problems solved by technology

[0002] In the production process of aluminum processing enterprises, there will be a large amount of waste water and sewage formed by waste acid. If the sewage is discharged directly, it will not only pollute the environment, but also waste a lot of resources.

The existing technology will do some treatment and discharge of sewage, but the existing sewage treatment process has defects such as high energy consumption, inability to recycle products or low recycling rate of products, incomplete sewage treatment, and single raw materials for sewage treatment.

[0003] Specifically: 1. In the prior art, sulfuric acid or waste sulfuric acid is added first and then aluminum-containing sludge is added in the feeding process. The disadvantage is that the aluminum-containing sludge is easily suspended in the upper layer of concentrated sulfuric acid in lumps, and the excessively high reaction temperature is contained. The aluminum sludge is closed to cause potential safety hazards; 2, the aluminum-containing sludge of the prior art is not treated, which will prolong the reaction time; 3, the prior art adopts the natural sedimentation method to take the supernatant after the reaction is complete for product production, The disadvantage is that the standing time is long, the stratification is unclear, and it is easy to produce substandard products; 4, the prior art raw material is single, and the product is only prepared by the reaction of aluminum-containing sludge and sulfuric acid; 6. The prior art has only studied the proportioning of reactant sulfuric acid and aluminum-containing sludge, and one-time reaction is used to prepare aluminum sulfate. This technology is very easy to make the product paste after the reaction is over because the concentration is too high. It is not conducive to the production of qualified aluminum sulfate products

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