Method for harmless treatment of electrolytic manganese slag directly in filter plate frame

Abstract

Provided is a method for directly carrying out innocent treatment on electrolytic manganese residues in filter pressing plate frames. The electrolytic manganese residues treated through the method are filter cakes obtained after filter pressing in the filter pressing plate frames of a plate-and-frame filter press, and sodium dihydrogen phosphate, calcium oxide, magnesium oxide and polyacrylamide are included in a treating agent. The method comprises the steps that 1, the electrolytic manganese residue filter cakes in all the filter pressing plate frames are washed through solutions obtained by mixing the sodium dihydrogen phosphate and water; 2, after the magnesium oxide, the calcium oxide and the polyacrylamide are dissolved in filter liquor collected in the step 1, the electrolytic manganese residue filter cakes are washed again; 3, filter liquor generated in the step 2 is collected, the plate-and-frame filter press is loosened to unload the filter cakes, and the electrolytic manganese residues generated after the innocent treatment are obtained. According to the method, soluble manganese in the electrolytic manganese residues is fixed, meanwhile, soluble ammonia nitrogen in the electrolytic manganese residues is fixed, and compared with the prior art, the advantages in the prior art are kept, the defects in the prior art are overcome, and the total cost of innocent treatment on the electrolytic manganese residues is lowered.

Description

technical field [0001] The invention relates to a method for harmless treatment of electrolytic manganese slag. Background technique [0002] Electrolytic manganese slag is a kind of industrial waste produced in the process of producing metal manganese by electrolysis. After it is pressed into a filter cake in a filter press workshop (usually using a plate and frame filter press), it still contains soluble manganese (Mn) and other Ionic NH 4 ＋ Ammonia nitrogen present. If such electrolytic manganese slag is piled up in the slag yard, the soluble manganese and ammonia nitrogen in it will be gradually transferred to the surrounding soil, groundwater and rivers under the erosion of rainwater, thereby destroying the surrounding ecological environment—not only causing excessive heavy metal content, It also causes serious water eutrophication. Even if people adopt the method of recycling, the soluble manganese and ammonia nitrogen in the electrolytic manganese slag cannot be co...

AI Technical Summary

Problems solved by technology

This prior art has indeed achieved better technical effects. However, since this prior art is to put the fresh electrolytic manganese slag with a water content as high as 25 to 30% (by mass) into the mixer for processing, the mixer is added. will inevitably increase the cost of the device

If the treatment is not timely and the filter cake-shaped electrolytic manganese slag is reprocessed after the event, then, in addition to increasing the cost of the device, it is also necessary to increase the procedures such as handling and restoring the moisture content of the electrolytic manganese slag to be treated. man-hour cost during processing

In addition, this prior art uses the way of release to deal with ammonia nitrogen. Although the method of "continuously recovering the ammonia gas generated during the stirring process" is adopted at the same time, this will inevitably increase the number of devices for recovering ammonia gas.

Originally, the environmental pollution caused by the ammonia nitrogen in the electrolytic manganese slag is the result of long-term accumulation, and the direct conversion of them into ammonia gas and release will definitely have an adverse effect on the health of the operator, but the cost of the device for recovering ammonia gas will be increased And greatly exceeds the value of the ammonia that can be recovered

Therefore, the prior art has the disadvantage that the total processing cost is relatively high