Optimal treatment method of nuclear wastewater

The best treatment methods of nuclear wastewater include chemical precipitation, ion exchange, adsorption, evaporation concentration and membrane separation technology.

1, chemical precipitation method

Chemical precipitation method is a method to reduce the content of radioactive elements in nuclear wastewater by using precipitation reaction between precipitant and radioactive elements. The advantages of this method are low cost, good removal effect for most radionuclides and simple operation.

However, this method also has some shortcomings, such as producing a large number of radioactive deposits, which need further treatment; For some radionuclides that are difficult to precipitate, such as cesium, ruthenium and iodine, special precipitants are needed, which increases the cost and difficulty.

2. Ion exchange method

Ion exchange method is a method of removing radioactive ions from water by adsorption of porous solid substances. The advantages of this method are high removal ability of radioactive strontium, cesium and cobalt, large exchange capacity, and effective reduction of the volume of nuclear wastewater; The requirements for water quality are not high, and all kinds of nuclear wastewater can be treated.

However, this method also has some shortcomings, such as the resin bed is easy to fail and needs to be replaced regularly; The resin bed is not easy to regenerate, and a large amount of radioactive waste resin is produced, which needs further treatment; For some radioactive ions that are difficult to adsorb, such as tritium and iodine, the effect is not good.

3. Adsorption method

Adsorption is a method to remove heavy metal ions from water by using porous solid substances. The advantage of this method is that it can remove many types of heavy metal ions, including some radioactive elements that are difficult to precipitate or exchange; The adsorbent is low in price, safe and easy to obtain; Simple operation and strong controllability.

However, this method also has some shortcomings, such as the adsorption capacity is affected by water quality and temperature; Adsorbent is easy to saturate and needs to be replaced regularly; The adsorbent is not easy to regenerate, and a large amount of radioactive waste adsorbent is produced, which needs further treatment.

4, evaporation concentration method

Evaporation concentration method is a method that uses evaporation device to evaporate water in nuclear waste water into water vapor, while radionuclide remains in water. The advantages of this method are high concentration coefficient and purification coefficient, which can effectively reduce the volume of nuclear wastewater; Suitable for all types and concentrations of nuclear wastewater; Some pure water can be recycled.

However, this method also has some disadvantages, such as high heat energy consumption and high operating cost; The evaporation device is prone to corrosion, scaling, explosion and other potential threats; A large amount of radioactive concentrated solution is produced, which needs further treatment.

5. Membrane separation technology

Membrane separation technology is a technology that uses semi-permeable membrane to separate solute and solvent in solution. The advantages of this technology are that the effluent quality is good and can meet the drinking water standard; The properties of nuclear waste water will not be changed if the materials remain unchanged; Low energy consumption and low operation cost; Some pure water can be recycled.

However, this technology also has some shortcomings, such as serious membrane pollution and the need for regular cleaning or replacement; The membrane has a short life and needs to be replaced frequently; The operating parameters are complex and need precise control.

Refer to the above content: Baidu Encyclopedia-Nuclear Sewage