A method for recovering blue iron ore from sludge incineration ash

Abstract

The invention relates to a method for recovering blue iron ore from sludge incineration ash, which comprises the following steps: (1) mixing sludge incineration ash with acid solution and heating for phosphorus leaching, and then filtering and separating to obtain leaching filtrate and leaching filter residue; (2) adjust the pH value of the leaching filtrate with lye, then add an adsorbent to carry out the adsorption of phosphorus, and then obtain the adsorption filtrate and adsorption filter residue through filtration and separation; (3) mix the adsorption filter residue with lye and carry out phosphorus removal (4) under anaerobic environment, add ferrous ions to the desorption filtrate, and adjust the pH value of the desorption filtrate to react, and obtain filter residue and filtrate, and the filter residue is washed and dried to obtain blue iron ore. Compared with the prior art, the invention eliminates the interference of other elements in the sludge incineration ash, obtains high-quality blue iron ore products, can alleviate the shortage of phosphorus resources, and has simple process flow and convenient operation.

Description

technical field [0001] The invention relates to the field of comprehensive utilization of solid waste resources, in particular to a method for recovering blue iron ore from sludge incineration ash. Background technique [0002] Phosphorus (P) is an essential element in living organisms and plays a vital role in life activities. As the global population continues to increase, so does the demand for phosphorus in agriculture and industry. However, phosphorus is a limited and non-renewable resource. About 20 million tons of phosphorus ore are mined every year, and the price of phosphorus continues to rise. At the same time, high-quality and easy-to-mine phosphate rocks are gradually depleted, and phosphate rocks with high impurities and difficult mining will be widely used, which will further increase the production cost of phosphorus products. According to the current exploitation and use speed of phosphorus, the phosphorus resources with mining economic benefits can only la...

AI Technical Summary

Problems solved by technology

However, this patent does not enrich and remove impurities for phosphate in the stream, and the high organic phosphorus content in the stream cannot be converted into blue iron ore, thus limiting the formation of blue iron ore; sulfide exists in high concentration, and an excessive supply of iron salt is required. After all the sulfide reaction is converted into iron sulfide, blue iron ore begins to form; and in the experiment, the sludge needs to be kept under anaerobic or anoxic conditions for 20 to 30 days, and the experiment takes a long time

Images