Filtering method:
The principle is basically the same as the water purifier that everyone usually uses. It is mainly to install materials that can adsorb radioactive substances at the position where radioactive waste water flows, so as to effectively adsorb radioactive substances in water and store them in the adsorption materials.
After waiting for a period of time, the radioactive substance in the material reaches saturation state, and a new adsorption material can be replaced. The replacement material filled with radioactive substances is cured and sealed.
Qinshan No.3 nuclear power plant is unique in that it adopts foreign heavy water reactor technology, is the first commercial candu nuclear power plant in China, and is extremely novel and distinctive in the design of nuclear wastewater treatment. It can greatly reduce the amount of secondary waste and greatly reduce the site use cost and wastewater treatment cost of nuclear power plants.
The waste water treatment system collects low-level, medium-level and high-level radioactivity respectively, and discharges it into the corresponding storage boxes according to the source and radioactivity of the waste water, so that the short-lived radioactive substances in it decay rapidly. In Qinshan No.3 Nuclear Power Station, two storage tanks store medium and high level radioactive wastewater, and three storage tanks store low level radioactive wastewater.
If the short-lived radioactive substances in the wastewater in the storage tank completely decay when the wastewater level reaches a certain height, start the circulating pump of the wastewater storage tank to keep running for more than 1 hour at this time, so that the wastewater in the storage tank can be fully mixed. If all indicators meet the discharge standards, the wastewater in the sampling and analysis box can be directly discharged to the outside.
Moderate radioactive waste water does not meet the direct discharge standard after treatment, and must be purified and decontaminated again. Process flow of radioactive wastewater purification loop.
If the pressure difference at the filter mouth of the system is abnormal during the operation of the equipment, the filter is blocked. At this time, the system filter must be replaced in time. If the absorbent material fails, it needs to be replaced. Sampling analysis is a direct reference to determine the number of purification cycles and purification effect.
Adsorption method:
There is a low-key news in the fifth issue of Urban Roads and Bridges and Flood Control in May, 20 1 1. China has successfully developed a new technology for fast and efficient adsorption and filtration of nuclear polluted wastewater, which can be used to prevent the diffusion of radioactive iodine isotopes such as iodine-13 1, and can be widely used in nuclear accident emergency, nuclear wastewater treatment and nuclear facility protection.
This high-tech major scientific and technological achievement will be rapidly transformed into productivity and economic benefits in Luohe City, Henan Province. The adsorption efficiency of this material for iodine-13 1 is shocking. Catalytic bioceramic particles, a new material 10g made by this new technology, can adsorb and fix up to 99.97% of radioactive iod20mine-13l when immersed in nuclear wastewater containing 12640bq/L radioactive iodine-13/.
The test shows that this new material can be used to filter iodine-125 wastewater with radioactivity as high as10.85 million bq/L. The removal rate of radioactive iodine-125 is as high as 2% after only using rainwater for five times. This new material is called catalytic bioceramics, but it is not a ceramic in the general sense, and it is also different from the traditional adsorption materials.
The particles made by this new technology are an efficient adsorption material with directional selectivity, which can quickly, simply and efficiently adsorb and fix radioactive substances such as iodine-13 1 and iodine-125. The core of this technology is to realize the functions of orientation, selective adsorption and fixation of materials.