Method for producing nano zinc oxide and calcium carbonate compound by utilizing zinc-containing raw ore

Abstract

The invention relates to a method for producing a nano zinc oxide and calcium carbonate compound by utilizing zinc-containing raw ore. The method comprises an extraction step, an optional purificationstep, a precipitation step, an optional rinsing step and a drying and calcination step. According to the method provided by the invention, wet-process leaching and a synthesis technology are combinedto realize economical and environment-friendly utilization of low-grade zinc oxide ore and an applicable range is wide; ammonia steaming is not needed and the method is simple and feasible; the energy consumption of a technology is greatly reduced; water treatment pressure, high-temperature and high-pressure potential safety hazards and equipment corrosion problems and the like, which are causedby the ammonia steaming, are also avoided; an obtained compound product can be directly used as a product and also can be used as a raw material for other industrial processes; the method provided bythe invention has small pollution and auxiliary materials are recyclable; the method has the advantages of energy saving, low investment, low cost and high yield.

Description

technical field [0001] The invention belongs to the technical field of inorganic chemical industry, relates to resource utilization of low-grade zinc-containing raw ore, in particular to a method for producing nano-zinc oxide and nano-calcium carbonate composites by utilizing low-grade zinc oxide raw ore. Background technique [0002] The production and consumption of zinc in my country ranks first in the world. Domestic zinc resources cannot meet the production requirements, and a large amount of zinc raw materials need to be imported every year. my country is a country rich in zinc oxide resources. The reserves of zinc metal in zinc oxide ore in my country are about 28 million tons, accounting for about 27.7% of the zinc metal reserves in zinc oxide ore in the world. Zinc oxide mines in my country generally have a low zinc grade, with an average grade of less than 5%. At present, the stagnant ore and lean ore reserves that cannot be economically utilized account for the va...

AI Technical Summary

Problems solved by technology

However, due to the composition of low-grade zinc oxide ore and the economic investment in process equipment, when using 3-6% ultra-low-grade zinc oxide ore, the zinc concentration in the leaching solution is low, and more than 50 cubic meters of zinc oxide products need to be produced per ton Evaporation of the zinc-ammonia complex liquid requires extremely high energy consumption, and the volatilization of ammonia during the heating and evaporation process is not easy to control, which is likely to cause environmental problems. At the same time, the conventional ammonia-ammonium bicarbonate method to prepare zinc oxide process uses direct steam heat exchange in the ammonia distillation process , the excess water brought in by the steam affects the water balance and increases the environmental protection treatment pressure of the process; in addition, in order to ensure the zinc concentration in the complexation liquid, it is necessary to increase the concentration of ammonia water in the leachate, facing environmental problems caused by ammonia volatilization

[0008] Therefore, the existing technology is not satisfactory for the utilization of low-grade zinc-containing raw ore