Domestic nuclear wastewater generally have three treatment methods, respectively, adsorption separation method, reverse osmosis method, ion exchange method.
1, adsorption separation method
In the radioactive water treatment process, a variety of coagulants and adsorbents are used to separate and remove radionuclides, such as radioactive cesium and cobalt. Usually use precipitation method as a temporary means to make radionuclides in the precipitant after the removal purpose. Adsorption separation method can effectively remove radioactive substances, but the production cost of this method is relatively high.
2, reverse osmosis
Reverse osmosis is a high concentration of nuclear pollutants from wastewater separation technology. This technology has the advantages of good purification effect, fast processing speed and relatively low cost, and is widely used in the field of nuclear wastewater treatment. The reverse osmosis method separates radionuclides by driving the wastewater under high pressure through the filtration of semi-permeable membrane.
3, ion exchange method
Ion exchange method is the water containing radioactive object ions through the resin and other adsorbents, so that the radioactive ions and the resin on the H + and other ions exchange, so as to separate them out of the technology. This method has the advantages of high efficiency, low cost and easy operation, and is widely used in the field of radioactive wastewater treatment.
Standards for Nuclear Wastewater Treatment
After nuclear wastewater is treated, the concentration of various radionuclides cannot exceed the national discharge limits or reuse standards. The concentration of typical nuclides such as americium and cesium should be lower than the limit values specified in GB14500. The salt content of the liquid phase after deep desalination should meet the requirements for reuse, and common indicators include chloride ion content and conductivity. It should be controlled within the requirements of reuse equipment such as circulating cooling tower.
The pH value of the treated nuclear wastewater should be close to neutral, generally controlled at 6.5-7.5 to prevent corrosion of stainless steel piping facilities. Suspended matter in the nuclear wastewater should be controlled below 10mg/L, with the maximum particle size less than 20μm, to prevent abrasion of pipeline facilities, the temperature of the treated nuclear wastewater should not be too high, and should be controlled within the temperature range required by the process, to prevent the impact on the ecological environment and reuse facilities.