In conjunction with the increasing demand for material cutting, such as the decommissioning and dismantling of nuclear facilities, advanced cutting technologies need be developed to increase precision and cost-effectiveness. As compared with other cutting technologies, laser cutting offers advantages of greater cutting precision, accuracy, and customization. In this work, we investigated the constitution, classification, and current status of this technology. Pollutant emission during laser cutting, corresponding pollution control methods and apparatus were proposed as well. Laser cutting equipment mainly comprises an automated system integrating a fiber laser, industrial computer, servo motor control, electrical control, and detection technology. It mainly consists of mechanical and electrical control parts. Laser cutting equipment is distinguished by light source, power, and cutting dimensions. Known variants of laser cutting technology involve vaporization, fusion, reactive fusion, and controlled fracture cutting. During the cutting process, dust, smoke, and aerosols can be released, which is an environmental concern and poses a threat to public health. The selection of the dedusting method and design of apparatus should take into account the dust removal rate, initial capital cost, maintenance cost, etc. Multi-stage filtration such as bag filtration combined with activated carbon filtration or electrostatic filtration is accepted.

The average share of nuclear energy in electricity production is expected to increase under the background of the global pursuit towards carbon neutrality. Conjugating with its rapid development, the wave of decommissioning and dismantling (D&D) of nuclear facilities is coming. The surface decontamination is a prerequisite to D&D, which will make it easier and reduce the volume of radioactive wastes. However, there are no comprehensive studies on the decontamination methods, which is not helpful for the sustainable development of nuclear energy and environment protection. Therefore, in this work, the current status and future trends of global energy and nuclear energy are first analyzed. Then, various decontamination approaches are comparatively studied, including cleaning mechanisms, application subjects, and intrinsic advantages and disadvantages. Finally, the criteria and factors for selecting a decontamination process, the challenges, and future studies are directed. Among the mechanical methods, laser-based cleaning is high-speed, having automation ability, and thus is promising, although it creates a dust and airborne contaminant hazard. In further studies, factors such as selecting a proper laser facility, optimizing operating parameters, and designing a high-efficiency dust collection system could be studied. Regarding the chemical method, chemical gels are good for decontaminating complex shapes and vertical and overhead surfaces. In addition, they can enhance other decon agents’ efficiency by improving contact time. However, the formulation of colloidal gels is complex and no gel type is useful for all contaminants. Therefore, novel and versatile gels need be developed to enlarge their application field. Combining various decontamination methods will often have better results and thus a reasonable and effective combination of these decontamination methods has become the main direction.

During the operation of a nuclear power plant, many main systems will generate variety of radioactive spent filter elements. These filter elements are main solid waste which need to be replaced regularly to keep safety of these systems. Because these filter elements have a certain level of radioactivity, the replacement operation has a higher risk. Therefore, according to the national and nuclear power plant radioactive waste regulations, it is necessary to ensure the safe and reliable operation of the radiation protection, make sure that operator and facilities are protected from radiation exposure or minimized. Based on the analysis of the filter element replacement process and equipment of domestic nuclear power units in service, combined with the requirements of newel construction of intelligent nuclear power plants, it is necessary to propose a radioactive spent filter element intelligent replacement ROBOT program. This paper discusses the design scheme of a new intelligent replacement robot for radioactive spent filter elements, and key issues involving fully automatic replacement technology for radioactive filter elements, such as filter layout and filter element replacement process optimization, robot grabbing actuator design, robot positioning mechanism design and accuracy guarantee, etc. have been systematically studied. A set of robot systems with intelligent replacement of radioactive irrationality have been developed. The test has been verified and the technical conditions for implementation in NPP have been met.

Drum filter is a large-scale filtration equipment in nuclear power plants, providing clean cooling water for nuclear power plants. At present, there are problems of easy blockage, short response time of the unit after blockage, and shutdown of the unit in severe cases during the operation of the drum filter in the in-service nuclear power plants. The analysis shows that the drum filter adopts the structure of “internal water intake”, and the garbage such as marine organisms remain on “inside” of the drum filter during operation, which makes it difficult to clean up and operate the inner garbage. When the marine organisms suddenly break out, if the amount of garbage cleaned by the drum filter is not enough to offset the amount of garbage entering, the garbage will accumulate continuously inside, which may lead the pressure difference between the inside and outside of the drum filter to suddenly increase, and then cause the circulating pump to trip or even the reactor to shut down. The inherent safety of the drum filter of this water intake method is low. To solve this problem, this paper puts forward a new concept of water intake of drum filter, that is, the concept of “external water intake”, which changes the water intake method of the drum filter, intercepts the garbage on the “outside” of the drum filter. Under the action of water flow, the garbage outside is not easy to remain on the net and block the drum filter, thereby fundamentally improving the inherent safety of the drum filter. A new type of “external water intake” drum filter was developed by using parametric and modular design method. The reliability of the drum filter was analyzed by using the FMEA failure mode and impact analysis method, and the weak links of the drum filter were found out, and optimization and improvement measures have been taken for the weak links. The ANSYS finite element analysis software is used to conduct a seismic analysis of the drum filter, which proves that the drum filter meets the requirements of the RCC-M specification and the seismic requirements of the third-generation nuclear power plants, which demonstrates the safety of the drum filter. Finally, through the physical prototype test, the design concept of “external water intake” was verified, and garbage cleaning capacity of the new drum filter meets the requirements of nuclear power plants. This type of drum filter has been popularized and applied to many HPR1000 projects under construction and newly built ones.