CN106676257A - Arsenic removal method of arsenic-containing waste residues - Google Patents

Abstract

The invention discloses a method for removing arsenic in arsenic-containing waste residues through a chloridizing volatilization method. The arsenic-containing waste residues and ferric chloride are mixed, the mass ratio of the arsenic-containing waste residues to the added ferric chloride is 100:(0.1-100):1, and chloridizing volatilization arsenic removal is carried out under the conditions that the reaction temperature ranges from 280 DEG C to 300 DEG C and the reaction time ranges from 40 min to 60 min. According to the method, the arsenic can be removed in the mode of arsenic trichloride relatively smaller in toxicity in a gas volatilization manner, the arsenic removal rate can reach about 90%, the recycling efficiency of other valuable metal elements in the arsenic-containing waste residues is improved, and the removal process is simple. The method can be widely applied to arsenic removal treatment of copper soot and various metallurgy arsenic-containing waste residues, provides a new thought for arsenic removal basic study and is a quite economical and effective arsenic removal method.

Description

A method for removing arsenic from waste residue containing arsenic

technical field

The invention relates to a technology for separating arsenic from valuable metals in waste slag in a nonferrous metal smelting process, in particular to a new method for removing arsenic from arsenic-containing waste slag.

Background technique

In recent years, with the continuous increase of my country's non-ferrous metal smelting capacity, the waste slag produced in the smelting process is constantly increasing, and its arsenic content varies from a few tenths of a percent to more than 20%. For example, tens of thousands of tons of arsenic enter the copper smelting system in China every year, and the arsenic in the copper slag will continue to circulate and enrich in the system, eventually making the requirements for arsenic content in copper smelting raw materials more and more stringent. At the same time, in the non-ferrous metal smelting process, the presence of arsenic not only poses a serious threat to the health of smelting operators and the environment, but also reduces the purity of smelted metals, seriously affects product performance, and increases production costs. Higher requirements, etc.

At present, there is no economical and efficient comprehensive recycling technology at home and abroad to deal with the arsenic-containing waste slag produced in the metal smelting process. Various metal smelting slags and soot are basically disposed of by stacking and returning to the furnace for resmelting. It not only occupies land, pollutes the environment, but also causes a huge waste of resources, which has become an important factor hindering the sustainable development of non-ferrous metal smelting enterprises. How to reduce the arsenic content in the arsenic-containing waste residue so as to efficiently recycle arsenic and valuable metals after arsenic removal is of great significance for protecting the environment and saving resources.

Contents of the invention

The object of the present invention is to provide a method for removing arsenic from arsenic-containing waste residue, which uses ferric chloride as the chlorination agent, mixes it with arsenic-containing waste residue in a certain proportion, roasts at a certain temperature, and chlorination volatilizes and recovers the arsenic in the waste residue. Arsenic element, recycling valuable metal elements in slag.

Technical scheme of the present invention: a method for removing arsenic from arsenic-containing waste residue, comprising the following process:

Mix dry arsenic-containing waste slag (copper-containing soot) with ferric chloride without crystal water, the mixing mass ratio is 100:0.1-100:1; in order to quickly volatilize the arsenic chloride, use argon as the roasting Carrying and protective gas; in order to volatilize the chloride of arsenic and minimize volatilization of ferric chloride, control the roasting temperature at 280-300°C and the roasting time at 40-60 minutes; mix the gas of argon and arsenic chloride Pass it into a gas collection bottle with water, dissolve arsenic chloride in water to collect, argon escapes to collect and recycle, and finally arsenic is volatilized and collected in the form of chloride, while iron and other valuable metals remain in the slag, thus The arsenic can be removed and the valuable metals in the arsenic-containing waste residue can meet the requirement of recyclability.

The present invention utilizes discarded arsenic-containing waste slag and adds ferric chloride to roast smelting slag, and the volatilization rate of arsenic is about 90%, thereby efficiently removing harmful impurity arsenic and obtaining secondary smelting raw materials containing valuable metals; the process of the present invention is short, The equipment is simple, the operating temperature is low, the reaction cycle is short, and no secondary pollution is caused. At the same time, the arsenic can be directly removed from the arsenic-containing waste residue at a lower cost, and the secondary smelting raw materials containing valuable metals and the aqueous solution of arsenic chloride can be obtained at the same time. It has good economic benefits; it saves valuable metal resources and land resources.

detailed description

The present invention is carried out in the existing closed tube type roasting furnace.

Example 1: Dry ferric chloride and arsenic-containing waste residue in a mass ratio of 1:100, roast at a temperature of 300°C, pass through protective gas argon, and roast for 50 minutes, and the volatilization rate of As reaches 89.45%. Under this condition, As and Fe elements can be well separated, thereby removing arsenic, and obtaining secondary smelting raw materials containing valuable metals.

Example 2: Dry ferric chloride and arsenic-containing waste residue in a mass ratio of 1:100, roast at 290°C, pass in protective gas argon, roast for 60 minutes, and the volatilization rate of As reaches 90.14%. Under this condition, As and Fe elements can be well separated, thereby removing arsenic, and obtaining secondary smelting raw materials containing valuable metals.

Example 3: Dry ferric chloride and arsenic-containing waste slag in a mass ratio of 0.1:100, roast at a temperature of 300°C, pass through protective gas argon, roast for 45 minutes, and the volatilization rate of As reaches 87.85%. Under this condition, As and Fe elements can be well separated, thereby removing arsenic, and obtaining secondary smelting raw materials containing valuable metals.

Example 4: Dry ferric chloride and arsenic-containing waste residue in a mass ratio of 0.5:100, roast at a temperature of 290°C, pass in protective gas argon, roast for 50 minutes, and the volatilization rate of As reaches 85.57%. Under this condition, As and Fe elements can be well separated, thereby removing arsenic, and obtaining secondary smelting raw materials containing valuable metals.

Example 5: Dry ferric chloride and arsenic-containing waste residue in a mass ratio of 0.8:100, roast at a temperature of 290°C, pass in protective gas argon, roast for 45 minutes, and the volatilization rate of As reaches 88.68%. Under this condition, As and Fe elements can be well separated, thereby removing arsenic, and obtaining secondary smelting raw materials containing valuable metals.

Claims (2)

1. a kind of arsenic removing method of arsenic-containing waste residue, is characterized in that：Including procedure below：By dry metallurgical slag and without the crystallization water Iron chloride mixing, mixing quality ratio be 100:0.1~100:1；The carrying as roasting and protective gas using argon gas；Roasting Temperature control is burnt at 280~300 DEG C, roasting time is controlled in 40~60min；Argon gas and arsenic chloride mixed gas are led to band water Gas collection bottle in, arsenic chloride is soluble in water to be collected, argon gas effusion collect recycle, final arsenic is with muriatic shape Formula volatilization is collected, and iron and other valuable metals are stayed in slag.

2. a kind of arsenic removing method of arsenic-containing waste residue according to claim 1, is characterized in that：It is embodied as：Will be dry Iron chloride and arsenic-containing waste residue press 100:1 quality proportioning, 290 degree of sintering temperature is passed through protective gas argon gas, roasting time 60min, The volatility of As reaches 90.14%；With this understanding, As can be made to separate well with Fe elements, so as to remove arsenic, and is contained The secondary smelting raw material of valuable metal.