A large number of temporary housings (THs) were used in the Yanqing zone of the Beijing 2022 Olympic and Paralympic Winter Games. Taking a kind of container house (CH) used in Yanqing zone as a model, the objective of this paper is to analyze the effect of insulation thickness on heating energy consumption and corresponding carbon emission. The effect of service life of THs on economic thickness was also discussed. The simulation model was developed using EnergyPlus and the heating energy consumption with different insulation materials was simulated based on the meteorological parameters of the top of Xiaohaituo Mountain (2177.5 m) and the Olympic/Paralympic Village (950 m) in Yanqing zone. In the simulation process, the thermal insulation performance of the CH was enhanced with reference to the requirements of GB/T 51350-2019 Technical Standard for Nearly Zero Energy Buildings (NZEB) on one hand. Additionally, the insulation performance was evaluated in terms of payback period and carbon emission. On the other hand, the economic thickness of different insulation materials (rock wool (RW), extruded polystyrene (XPS), polyurethane (PU)) and the high performance vacuum insulation panel (HVIP)) for different service lives of CH was studied. Results show that the U-values of the envelope meeting the NZEB standard can decrease approximately 21.4–32.8% of the heating energy consumption, compared with the original envelope. When the service life of CH is extended to 20 years, the carbon emission is reduced by 18.5% and 29.5%. The payback period of HVIP is longest, up to 31.4 a, and the results of economic thickness show that when the service life of the CH ranges from 1 year to 20 years, the economic thickness range of RW is 47–235 mm, XPS is 41–197 mm, PU is 33–149 mm and HVIP is 4–18 mm at the altitude of 2177.5 m. At the altitude of 950 m, the economic thickness range of RW is 28–158 mm, XPS is 26–131 mm, PU is 25–118 mm, and HVIP is 2–12 mm. From an economic point of view, the service life of a CH has a significant impact on the choice of insulation thickness.

In our previous study, it was noticed that the combined freezing, soaking and centrifugal desalination (FSCD) process is unsuitable to be applied in summer, because very little pure ice can be produced when the temperature of raw seawater used as soaking liquid reaches 27 °C. Therefore, two main efforts on the process optimization were made in this paper. One is that low-temperature seawater served as soaking liquid in all the experiments. In real industrial practice, the low-temperature soaking liquid can be obtained through melting pure ice products or recovering cold energy from cold concentrated brine. The effects of centrifugal parameters and soaking time on salt removal efficiency and ice yield rate were investigated. Second, the gravity-induced method was combined to form freezing, soaking, gravity-induced and centrifugal desalination (FSGCD) processes for further improvement of the salt removal efficiency. The influence of melting time of gravity-induced process was studied by keeping the samples ambient with an air temperature of 30 °C. Finally, the performance among different processes was compared. Results showed that the salt removal efficiency of the FSGCD process can reach up to 97.03%. The study is helpful to improve the process performance of soaking treatment in summer application.

In this paper, a numerical study was carried out to analyze the smoke exhaust effect under different patterns. Fixed, movable, fixed-movable combined patterns and various settings in each pattern are taken into account. Smoke spread and tunnel ceiling temperature are the main characteristics of smoke exhaust effect. Results show that under normal operating condition of fixed pattern, the smoke spread in the upstream of the fire source can be suppressed. Under the fixed-movable combined pattern, the addition of the movable fan further produces a cooling effect on the downstream of the fire source, which is helpful to maintain the temperature downstream below the safe temperature threshold. In the movable smoke exhaust pattern, the influences of the inclined angle of the movable fan and the distance from the fire source are related to the air volume of the moving fan. When applying the arrangement pattern of movable fans in series, compared with increasing the number of movable fan of the same specification, increasing the ventilation volume of movable fan has a more significant effect on reducing the temperature in the tunnel.