CN106390961B - Adsorbent for removing uranium from cigarette ash and method for treating low-concentration uranium-containing wastewater - Google Patents

Abstract

An adsorbent for removing uranium from cigarette ash and a method for treating low-concentration uranium-containing wastewater. The adsorbent for removing uranium from cigarette ash is obtained by washing and drying waste soot generated in cigarette production. After collection, clean it with water, put it in a drying oven for drying, the drying temperature is 50°C-70°C, and the drying time is 20h-30h, and then the dried soot is passed through a 60-mesh sieve to obtain a soot powder with a particle size of less than 60 mesh. Then the soot powder is washed with water, and vacuum-dried at a temperature of 50° C. to 70° C. for 8 hours to 12 hours to obtain an adsorbent for removing uranium from cigarette soot. When treating uranium in uranium-containing wastewater, adjust the pH value of the uranium-containing wastewater to ^4-6 , and then add the adsorbent for removing uranium from cigarette ash for adsorption. The temperature is 10°C-50°C, and the adsorption is performed by a constant temperature water bath oscillator, and the adsorption oscillation time is 10min-140min.

Description

Adsorbent for removing uranium from cigarette ash and method for treating low-concentration uranium-containing wastewater

technical field

The invention relates to the technical field of uranium ore metallurgy, in particular to an adsorbent for removing uranium from cigarette soot and a method for removing uranium in low-concentration uranium-containing wastewater by using the adsorbent for removing uranium from cigarette soot.

Background technique

While the development of nuclear technology has brought huge economic and social benefits to the society, it also produces radioactive waste. If the low-concentration uranium-containing wastewater in uranium mining and metallurgy production directly enters the water body, it will pose serious harm to human health and the ecological environment. How to efficiently treat uranium-containing wastewater and recover uranium has become an urgent nuclear environmental problem to be solved.

At present, the treatment methods for uranium-containing wastewater mainly include chemical precipitation, ion exchange, membrane separation and adsorption. The chemical precipitation method has simple equipment, low cost and high efficiency, but the polymer produced by the reaction needs further treatment; the ion exchange method has a good removal effect, but is expensive and has limited exchange capacity; the membrane separation method is simple to operate and low in energy consumption, but it is Raw water has high water quality requirements and often needs to be used in conjunction with other water treatment technologies; and adsorption method has attracted much attention because of its high treatment efficiency and the ability to recover uranium.

During the cigarette production process, a large amount of waste soot will be produced. At present, the waste soot produced in the cigarette production process is generally treated as garbage, incinerated or landfilled, which not only causes certain pollution to the environment, but also causes a waste of resources.

The surface of soot contains abundant functional groups that can react with metal ions, and has strong adsorption capacity. The use of soot produced in cigarette production as an adsorbent for removing uranium from low-concentration uranium-containing wastewater has the advantages of low cost, good selectivity, and high treatment efficiency.

Contents of the invention

The purpose of the present invention is to overcome the above-mentioned shortcomings of the prior art and provide an adsorbent for removing uranium from cigarette soot and a method for removing uranium in low-concentration uranium-containing wastewater by using the adsorbent for removing uranium from cigarette soot.

The technical solution of the present invention is: an adsorbent for removing uranium from cigarette ash. The adsorbent for removing uranium from cigarette ash is obtained after washing and drying waste soot generated in cigarette production. The specific operation steps are as follows:

Collect the waste soot generated in cigarette production, wash it with water, put it into a drying oven for drying, the drying temperature is 50°C-70°C, and the drying time is 20h-30h, and then the dried soot is passed through a 60-mesh sieve to obtain Soot powder with a particle size of less than 60 mesh, then the soot powder is washed with water, and vacuum-dried at a temperature of 50°C to 70°C for 8h to 12h to obtain an adsorbent for removing uranium from cigarette soot.

The present invention also provides a method for removing uranium in low-concentration uranium-containing wastewater by using cigarette soot uranium-removing adsorbent. The concentration of uranium in the uranium-containing wastewater is 10g-40g/ ^m3 , and the pH value is 2-8. The specific operation Proceed as follows:

Adjust the pH value of the uranium-containing wastewater to ^4-6 , and then add an adsorbent for removing uranium from cigarette ash to perform adsorption. The adsorption adopts a constant temperature water bath oscillator to vibrate and adsorb, and the adsorption oscillation time is 10min to 140min.

When the adsorbent for removing uranium from cigarette soot is saturated, use hydrochloric acid or nitric acid as the desorbing adsorbent to desorb the uranium in the adsorbent for removing uranium from cigarette soot, then wash it repeatedly with distilled water until neutral, dry it and reuse it.

Compared with the prior art, the present invention has the following characteristics:

The invention adopts waste soot produced in cigarette production to be washed and dried as a uranium-removing adsorbent to remove uranium in low-concentration uranium-containing wastewater, has less secondary pollution, low treatment cost, easy regeneration of the adsorbent, and can recover uranium.

The detailed structure of the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

Description of drawings

Accompanying drawing 1 is the impact curve diagram of the uranium-containing wastewater of different pH values on adsorption capacity and removal rate;

Accompanying drawing 2 is the impact curve diagram of different adsorbent input amounts on adsorption capacity and removal rate;

Accompanying drawing 3 is the impact curve diagram of the uranium-containing wastewater of different concentrations on adsorption capacity and removal rate;

Accompanying drawing 4 is the influence curve diagram of different adsorption time to uranium adsorption amount and removal rate;

Accompanying drawing 5 is the graph of the influence of different adsorption temperatures on the adsorption amount and removal rate of uranium.

Detailed ways

Embodiment 1. Adsorbent for removing uranium from cigarette ash. The adsorbent for removing uranium from cigarette ash is obtained by washing and drying waste soot generated in cigarette production. The specific operation steps are as follows:

Collect the waste soot generated in cigarette production, wash it with water, put it in a drying oven for drying, the drying temperature is 50 ° C, and the drying time is 30 hours, and then the dried soot is passed through a 60-mesh sieve to obtain a particle size of less than 60 mesh Soot powder, and then the soot powder was washed with water, and vacuum-dried at 50°C for 12 hours to obtain an adsorbent for removing uranium from cigarette soot.

Embodiment 2: Adsorbent for removing uranium from cigarette ash. The adsorbent for removing uranium from cigarette ash is obtained by washing and drying waste soot generated in cigarette production. The specific operation steps are as follows:

Collect the waste soot generated in cigarette production, wash it with water, put it in a drying oven for drying, the drying temperature is 60°C, and the drying time is 25 hours, and then pass the dried soot through a 60-mesh sieve to obtain a particle size of less than 60 mesh Soot powder, and then the soot powder was washed with water, and vacuum-dried at 60°C for 10 hours to obtain an adsorbent for removing uranium from cigarette soot.

Embodiment 3: Adsorbent for removing uranium from cigarette ash. The adsorbent for removing uranium from cigarette ash is obtained after washing and drying waste soot generated in cigarette production. The specific operation steps are as follows:

Collect the waste soot generated in cigarette production, wash it with water, put it in a drying oven for drying, the drying temperature is 70°C, and the drying time is 20 hours, and then pass the dried soot through a 60-mesh sieve to obtain a particle size of less than 60 mesh soot powder, and then the soot powder was washed with water, and vacuum-dried at 70° C. for 8 hours to obtain an adsorbent for removing uranium from cigarette soot.

Embodiment 4. A method for removing uranium in low-concentration uranium-containing wastewater by using cigarette soot uranium-removing adsorbent. The concentration of uranium in the uranium-containing wastewater is 10g-40g/m ³ , and the pH value is 2-8. The specific operation steps are as follows:

Adjust the pH value of the uranium-containing wastewater to 4, and then add the adsorbent for removing uranium from cigarette soot for adsorption. The amount of the adsorbent for removing uranium from cigarette soot is 7g/m ³ , the adsorption temperature is 50°C, and the adsorption is oscillated by a constant temperature water bath oscillator Adsorption, the adsorption oscillation time is 140min.

When the adsorbent for removing uranium from cigarette soot is saturated, use hydrochloric acid or nitric acid as the desorbing adsorbent to desorb the uranium in the adsorbent for removing uranium from cigarette soot, then wash it repeatedly with distilled water until neutral, dry it and reuse it.

Embodiment 5. A method for removing uranium in low-concentration uranium-containing wastewater by using cigarette soot uranium-removing adsorbent. The concentration of uranium in the uranium-containing wastewater is 10g-40g/ ^m3 , and the pH value is 2-8. The specific operation steps are as follows:

Adjust the pH value of uranium-containing wastewater to 5, and then add uranium-removing adsorbent for cigarette soot for adsorption. The amount of uranium-removing adsorbent for cigarette soot is 4g/m ³ , the adsorption temperature is 30°C, and the adsorption is oscillated by a constant temperature water bath oscillator Adsorption, the adsorption oscillation time is 100min.

When the adsorbent for removing uranium from cigarette soot is saturated, use hydrochloric acid or nitric acid as the desorbing adsorbent to desorb the uranium in the adsorbent for removing uranium from cigarette soot, then wash it repeatedly with distilled water until neutral, dry it and reuse it.

Embodiment 6. A method for removing uranium in low-concentration uranium-containing wastewater by using cigarette soot uranium-removing adsorbent. The concentration of uranium in the uranium-containing wastewater is 10g-40g/m ³ , and the pH value is 2-8. The specific operation steps are as follows:

Adjust the pH value of uranium-containing wastewater to 6, and then add cigarette soot uranium-removing adsorbent for adsorption. The amount of cigarette soot uranium-removing adsorbent is 1g/m ³ , the adsorption temperature is 10°C, and the adsorption is oscillated by a constant temperature water bath oscillator Adsorption, the adsorption oscillation time is 10min.

When the adsorbent for removing uranium from cigarette soot is saturated, use hydrochloric acid or nitric acid as the desorbing adsorbent to desorb the uranium in the adsorbent for removing uranium from cigarette soot, then wash it repeatedly with distilled water until neutral, dry it and reuse it.

Test the treated uranium-containing wastewater, including:

A. Detection of uranium-containing wastewater with different pH values: the initial concentration of uranium is 20 mg/L, the dosage of adsorbent is 4g/L, and the pH values are 2, 3, 4, 5, 6, 7, 8 respectively , the adsorption temperature is 30°C, oscillating at a rate of 200r/min for 100min, filtering, taking the supernatant, and using a spectrophotometer to measure the residual uranium concentration in the uranium-containing wastewater. The results showed that the removal rates of uranium were 43.5%, 71%, 87.4%, 94.2%, 93.1%, 92.4%, and 91.3%, respectively.

Accompanying drawing 1 is the impact curve diagram of the uranium-containing wastewater of different pH values on adsorption capacity and removal rate, wherein, R is removal rate curve, Q is adsorption capacity curve, as can be seen from accompanying drawing 1, when pH value is 5 , the removal rate and adsorption amount of uranium reached the maximum value, and then with the increase of pH value, the removal rate and adsorption amount of uranium decreased instead.

B. Detection of uranium-containing wastewater with different adsorbent input amounts: the initial concentration of uranium is 20mg/L, the adsorption temperature is 30°C, the pH value is 5, and the adsorbent dosage is 1 g/L and 2 g/L respectively , 3 g/L, 4 g/L, 5 g/L, 6 g/L, 7 g/L, oscillating at a rate of 200 r/min for 100 min, filtering, taking the supernatant, and using a spectrophotometer to measure the content of Residual uranium concentration in uranium wastewater. The results showed that the removal rates of uranium were 42.6%, 68.6%, 84.4%, 93.2%, 94.4%, 95%, 95.2%, respectively.

Accompanying drawing 2 is the impact curve diagram of different adsorbent input amount on adsorption capacity and removal rate, wherein, R is the removal rate curve, Q is the adsorption capacity curve, as can be seen from accompanying drawing 2, the adsorbent dosage is 1 g /L, the adsorption capacity of uranium is the largest, but the removal rate of uranium is low. With the increase of adsorbent dosage, the removal rate of uranium increased gradually, and the adsorption amount decreased gradually.

C. Detection of uranium-containing wastewater with different concentrations: the adsorption temperature is 30°C, the pH value is 5, the dosage of adsorbent is 4 g/L, and the uranium concentrations in uranium-containing wastewater are 5 mg/L and 10 mg respectively /L, 15 mg/L, 20 mg/L, 25 mg/L, 30mg/L, 35 mg/L, 40 mg/L, absorb at a constant temperature of 200r/min for 100min, filter, and take the supernatant, Determination of residual uranium concentration in uranium-containing wastewater using a spectrophotometer. The results showed that the removal rates of uranium were 97.4%, 96.1%, 94.5%, 93%, 84.6%, 72%, 62.5%, 55.4%, respectively.

Accompanying drawing 3 is the impact curve diagram of the uranium-containing wastewater of different concentrations on adsorption capacity and removal rate, wherein, R is removal rate curve, Q is adsorption capacity curve, as seen from accompanying drawing 3, along with the raising of uranium initial mass concentration, The removal rate of uranium showed a downward trend, but the adsorption amount gradually increased.

D. Detection of uranium-containing wastewater with different adsorption times: the initial concentration of uranium is 20mg/L, the adsorption temperature is 30°C, the pH value is 5, the dosage of adsorbent is 4 g/L, and the adsorption time is 10min and 20min respectively , 30min, 60min, 80min, 100min, 120min, 140min, absorb at a constant temperature at a rate of 200r/min, filter, take the supernatant, and use a spectrophotometer to measure the residual uranium concentration in the uranium-containing wastewater. The results showed that the removal rates of uranium were 68.8%, 76%, 80.6%, 88.2%, 91.6%, 94.6%, 94.8%, and 95%, respectively.

Accompanying drawing 4 is the influence curve diagram of different adsorption time on the uranium adsorption amount and removal rate, wherein, R is the removal rate curve, Q is the adsorption amount curve, as can be seen from the accompanying drawing 4, 0～20min is a fast adsorption process, The removal rate and adsorption capacity of the adsorbent for uranium increased rapidly. With the extension of the adsorption time, the removal rate and adsorption capacity gradually increased but the growth rate decreased. After 100 minutes, the reaction basically reached equilibrium, and the removal rate tended to balance.

E. Detection of uranium-containing wastewater at different adsorption temperatures: the initial concentration of uranium is 20 mg/L, the pH value is 5, the dosage of adsorbent is 4 g/L, and the temperatures are 10°C, 15°C, 20°C, 25°C, respectively. °C, 30 °C, 35 °C, 40 °C, 45 °C, 50 °C, constant temperature oscillation at a rate of 200 r/min for 100 min, filter, take the supernatant, and use a spectrophotometer to measure the residual uranium concentration in the uranium-containing wastewater. The results showed that the removal rates of uranium were 73.5%, 79.8%, 85.8%, 90.7%, 94.1%, 94.8%, 95.3%, and 96%, respectively.

Accompanying drawing 5 is the impact curve diagram of different adsorption temperatures on uranium adsorption amount and removal rate, wherein, R is removal rate curve, Q is adsorption amount curve, by accompanying drawing 5, we can know that the removal rate of uranium and adsorption amount increase with the increase of adsorption temperature. When the adsorption temperature is lower than 30 ℃, the removal rate and adsorption capacity increase rapidly. When the adsorption temperature is between 30 ℃ and 50 ℃, the growth rate of uranium removal rate and adsorption amount slows down, and the change is not large, which shows that increasing the adsorption temperature is beneficial to the adsorption of uranium by the adsorbent.

By testing the treated uranium-containing wastewater, the removal rate of uranium by the adsorbent is related to the pH value, concentration, adsorption time, adsorbent dosage and adsorption temperature of the uranium-containing wastewater. When the pH value is 5 and the concentration is 25 mg/ L. The adsorption effect is the best when the adsorption time is 100min, the amount of adsorbent is 4 g/L and the adsorption temperature is 30°C.

Claims (2)

1. A method for removing uranium in low-concentration uranium-containing wastewater by using cigarette ash uranium-removing adsorbent, characterized in that: the concentration of uranium in the uranium-containing wastewater is 10g-25g/m ³ , the pH value is 4-8, and the specific operation steps as follows: Adjust the pH value of the uranium-containing wastewater to ^4-6 , and then add an adsorbent for removing uranium from cigarette soot to perform adsorption. The adsorption adopts a constant temperature water bath oscillator to oscillate and adsorb, and the adsorption oscillation time is 60min to 140min; The cigarette soot uranium-removing adsorbent is obtained by washing and drying the waste soot produced in cigarette production. The waste soot produced in cigarette production is collected, washed with water, and put into a drying oven for drying. The drying temperature is 50°C ~70°C, the drying time is 20h~30h, then pass the dried soot through a 60-mesh sieve to obtain soot powder with a particle size of less than 60 mesh, then wash the soot powder with water, and dry it in vacuum at 50°C-70°C for 8 hours ～12 h, the adsorbent for removing uranium from cigarette ash was obtained. 2. The method for removing uranium in low-concentration uranium-containing wastewater as claimed in claim 1, characterized in that: after the adsorption of the cigarette ash deuranium adsorbent is saturated, hydrochloric acid or nitric acid is used as the analytical adsorbent to remove uranium from the cigarette ash and adsorb The uranium in the reagent is resolved, and then washed repeatedly with distilled water to neutrality, and then reused after drying.

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