阅读说明：本技术 一种铅废料脱硫的方法 (Method for desulfurizing lead waste ) 是由 代少振 项晨 于 2020-10-09 设计创作，主要内容包括：本发明涉及一种铅废料脱硫的方法,其特征在于,包括如下步骤：步骤1：铅废料与碳酸氢氨反应脱硫；步骤2,固液分离后,得到碳酸铅与硫酸氨母液；步骤3,硫酸氨母液加入碳酸钙反应,得到碳酸氢氨和硫酸钙；步骤4,所述步骤3得到的碳酸氢氨返回步骤1继续脱硫。本发明的铅废料脱硫的方法可循环利用、效率高、成本低。(The invention relates to a method for desulfurizing lead waste, which is characterized by comprising the following steps: step 1: reacting the lead waste with ammonium bicarbonate for desulfurization; step 2, obtaining lead carbonate and ammonium sulfate mother liquor after solid-liquid separation; step 3, adding calcium carbonate into the ammonium sulfate mother liquor to react to obtain ammonium bicarbonate and calcium sulfate; and 4, returning the ammonium bicarbonate obtained in the step 3 to the step 1 to continue desulfurization. The method for desulfurizing the lead waste can be recycled, and has high efficiency and low cost.)

1. A method for desulfurizing lead scrap is characterized by comprising the following steps: step 1: reacting the lead waste with ammonium bicarbonate for desulfurization; step 2, obtaining lead carbonate and ammonium sulfate mother liquor after solid-liquid separation; step 3, adding calcium carbonate into the ammonium sulfate mother liquor to react to obtain ammonium bicarbonate and calcium sulfate; and 4, returning the ammonium bicarbonate obtained in the step 3 to the step 1 to continue desulfurization.

2. The method for desulfurizing lead scrap according to claim 1, wherein in the step 3, the carbon dioxide gas generated in the step 1 is introduced while calcium carbonate is added to the ammonium sulfate mother liquor for reaction.

3. The method for desulfurizing lead scrap according to claim 1 or 2, wherein in the step 1, the waste lead plaster and the ammonium bicarbonate are mixed according to a molar mass ratio of 1:2 to 1: 5, putting the mixture into a ball milling or shearing reaction tank, and then adding a mixture of the mixture and waste lead paste in a mass ratio of 2: 1, grinding, desulfurizing and converting for 10-60min at the temperature of 0-45 ℃ for desulfurizing.

4. The method for desulfurizing lead scrap according to claim 1 or 2, wherein calcium carbonate is added in the step 3, and carbon dioxide gas generated in the step 1 is introduced under stirring or grinding conditions, and the reaction temperature is 0-50 ℃ and the reaction time is 15-60 min.

Technical Field

The invention relates to the technical field of waste treatment.

Background

The lead-acid battery has excellent charge and discharge performance, strong temperature adaptability, low price, safety and reliability, so the lead-acid battery is widely applied in the fields of energy storage, communication base stations, national defense equipment, automobiles, electric vehicles, motorcycles and the like. Along with the rapid development of economy in China in recent years, the basic industries of automobiles, communication, electric power, traffic, railways, computers and the like are increasing at a high speed, the demand on lead-acid storage batteries is continuously increased, the increasing speed reaches 10% in the last decade, and the development of the lead-acid storage battery industry is greatly promoted. The scrapping period of the lead-acid storage battery per se caused by corrosion, passivation and the like is generally 3-5 years, more than 1.1 hundred million lead-acid storage batteries are scrapped every year, and the lead content is as high as 380 million tons, so that the regeneration of the waste lead-acid storage battery has great significance for environmental protection and lead resource circulation. At present, the industrial policy and technical equipment system of green cycle of waste lead storage battery resources are preliminarily established in China, and the cleaning process of mechanical crushing and sorting, pre-desulfurization and low-temperature smelting is generally implemented. Wherein, two links of mechanical crushing and sorting and low-temperature smelting are supported by fully advanced and efficient technical equipment. The process commonly adopted in the 'lead plaster pre-desulfurization' link is sodium salt and ammonia salt desulfurization, high-melting point lead sulfate is converted into low-melting point lead carbonate, efficient and thorough desulfurization is realized, the environmental benefit is outstanding, but the by-product needs to be prepared into sodium sulfate or ammonium sulfate after high-energy-consumption concentration crystallization due to high raw material value, the value is low, the economic benefit is not good, and further development of the waste lead storage battery regeneration industry is restricted. The invention provides a high-cleanness low-cost storage battery desulfurization method.

Disclosure of Invention

In order to solve the technical problem, the invention provides a method for desulfurizing lead waste, which is characterized by comprising the following steps: step 1: reacting the lead waste with ammonium bicarbonate for desulfurization; step 2, obtaining lead carbonate and ammonium sulfate mother liquor after solid-liquid separation; step 3, adding calcium carbonate into the ammonium sulfate mother liquor to react to obtain ammonium bicarbonate and calcium sulfate; and 4, returning the ammonium bicarbonate obtained in the step 3 to the step 1 to continue desulfurization.

Further, in the step 3, calcium carbonate is added into the ammonium sulfate mother liquor for reaction, and carbon dioxide gas generated in the step 1 is introduced at the same time.

Further, in the step 1, the waste lead plaster and the ammonium bicarbonate are mixed according to a molar mass ratio of 1:2 to 1: 5, putting the mixture into a ball milling or shearing reaction tank, and then adding a mixture of the mixture and waste lead paste in a mass ratio of 2: 1, grinding, desulfurizing and converting for 10-60min at the temperature of 0-45 ℃ for desulfurizing.

Further, in the step 3, calcium carbonate is added, and carbon dioxide gas generated in the step 1 is introduced under the stirring or grinding condition, the reaction temperature is 0-50 ℃, and the reaction time is 15-60 min.

The method for desulfurizing the lead waste can be recycled, and has high efficiency and low cost.

Drawings

FIG. 1 is a flow diagram of the desulfurization of lead scrap in accordance with the present invention.

Detailed Description

The invention is further described below with reference to the specific drawings.

As shown in fig. 1, the method for desulfurizing lead scrap according to the present invention comprises the following steps:

step 1 desulfurization of waste lead plaster and ammonium bicarbonate

Putting waste lead plaster (calculated by lead sulfate) and ammonium bicarbonate into a ball milling or shearing reaction tank according to a molar mass ratio (1:2-5), and then adding a mixture of the waste lead plaster and the ammonium bicarbonate, wherein the mass ratio of the waste lead plaster to the waste lead plaster is 2: 1, grinding, desulfurizing and converting the pure water at the temperature of 0-45 ℃ for 10-60min to generate lead carbonate, ammonium sulfate, carbon dioxide and water, and trapping the carbon dioxide for the next step for reuse. The conversion efficiency of the lead sulfate is more than 99.5 percent, and the mixed slurry is transferred to a buffer tank for standby after the grinding reaction is finished.

The desulfurization process occurs as follows.

The reaction equation is as follows: PbSO4+2NH4HCO3 → PbCO3+ (NH4)2SO4+ H2O + CO2 step 2 solid-liquid separation of mixed slurry

And carrying out filter pressing on the mixed slurry in the buffer tank for solid-liquid separation to obtain the desulfurized lead plaster and the ammonium sulfate solution.

Step 3 regeneration of ammonium bicarbonate mother liquor

Putting the ammonia sulfate mother liquor after the lead plaster desulfurization into a reaction kettle, adding calcium carbonate, slowly introducing carbon dioxide gas generated in the first step into the reaction kettle under the stirring or grinding condition, reacting at the temperature of 0-50 ℃ for 15-60 min to generate calcium sulfate precipitate and ammonium bicarbonate, wherein the conversion efficiency of the ammonium sulfate is more than 99%, and in the process, 1% of regeneration and conversion are incomplete, and the ammonium sulfate precipitate and the ammonium bicarbonate are supplemented with new ammonium bicarbonate for balance. The reaction is as follows:

the reaction equation is as follows:

(NH4)2SO4+CaCO3+Co2+H2O→2NH4HCO3+CaSO4↓

and 4, returning the ammonium bicarbonate obtained in the step 3 to the step 1 to continue desulfurization.

Combining the above reaction equations: the PbSO4+ CaCO3 → PbCO3+ CaSO4 raw materials are only limestone which is cheap and easy to obtain, and equivalent calcium sulfate can be obtained, so the desulfurization method is the most economic method in the storage battery industry at present.

The above-described embodiments are only preferred embodiments of the present invention, and are not intended to limit the present invention in any way, and other variations and modifications may be made without departing from the spirit of the invention as set forth in the claims.