Process for regenerating hydrochloric acid for chloridizing laterite nickel ore by wet method

Abstract

The invention relates to a method for reproduction and utilization of hydrochloric acid in the process of extracting nickel and cobalt from laterite nickel ore. A chlorination treatment process of laterite nickel ore by wet method comprises the steps of preparing laterite nickel ore, leaching out chloride, concentrating leaching solution, precipitating by sulfurization, recovering hydrochloric acid, etc. The calcinating materials in the inventive hydrochloric acid reproduction process comprise the concentrated solution of the mother liquid after nickel precipitation, iron chloride and magnesium chloride crystals obtained during concentration of the leaching solution, and coal powder. The inventive method comprises the steps of mixing and blending materials to obtain slurry, and spraying into a high-temperature furnace, or calcinating the materials in high-temperature furnaces at 500-800DEG C, hydrolyzing metallic chloride into hydrogen chloride and metal oxide, heating the concentrated leaching solution by using the residual heat from the hot furnace gas, and absorbing the hydrogen chloride to reproduce hydrochloric acid, so as to realize closed circuit circulation of the hydrochloric acid. The high-viscosity ferric oxide and magnesium oxide dregs are cooled, broken and pulverized to powder, which is used as a byproduct for treatment. The inventive method improves the conversion rate and equipment productive capacity during chloride reproduction process, reduces energy consumption in hydrochloric acid reproduction, and realizes comprehensive utilization of the residual heat in hydrochloric acid reproduction.

Description

technical field [0001] The invention relates to a method for recycling hydrochloric acid in the process of extracting nickel and cobalt from laterite nickel ore, which belongs to the field of nonferrous metallurgy. Background technique [0002] Laterite nickel ore is a kind of nickel oxide ore, accounting for more than 65% of the total nickel reserves. Lateritic nickel ore can be divided into limonite type and silicon magnesium nickel ore type. The limonite type is located in the upper part of the deposit, with high iron, low nickel, low silicon and magnesium, but relatively high cobalt content, and should be treated by hydrometallurgy. The silicon-magnesium-nickel ore is located in the lower part of the deposit. The content of silicon and magnesium is relatively high, the content of iron and cobalt is relatively low, but the content of nickel is relatively high, so it should be treated by pyrometallurgy. The ore in the middle transition can adopt pyrometallurgy or hydrome...

AI Technical Summary

Problems solved by technology

However, in the current hydrochloric acid regeneration process, the mother liquor after nickel precipitation is generally concentrated and then directly roasted at high temperature, which has problems such as high energy consumption and low equipment capacity, which makes the hydrochloric acid regeneration cost very high.