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Radioactive contamination caused by nuclear leakage accidents and radioactive source diffusion accidents will pose a threat to the environment and public safety. In order to remove the contamination, an emergency decontamination technique based on strippable coating was studied. The strippable coating takes acrylate emulsion as the main film forming agent and lauryl sodium sulphate as surfactant. The decontamination performance and application dosage of the coating were tested. At the application dosage of 2.5 kg m−2, the single decontamination rate reached 92.26% for uranium dust on concrete surface, which indicates this technology is a promising method for engineering decontamination.

In this paper, we investigated the kinetics and thermodynamics of phosphorus adsorption by a new efficient phosphorus removal composite (EPRC). Kinetic analysis showed that the adsorption of phosphorus by EPRC is best described by a pseudo-first-order equation. Thermodynamic analysis showed that the Gibbs free energy (ΔG°) is negative, implying that the reaction is spontaneous. Moreover, the change in enthalpy (ΔH°) of phosphorus adsorption by EPRC was always greater than 60 kJ/mol, indicating that the adsorption was an endothermic chemical process. Furthermore, EPRC adsorbs phosphorus better at higher temperatures.

The mechanism of phosphorus removal by iron-contactor process (PRICP) is illustrated from two aspects: metallic corrosion and phosphorus removal by ferric salt. Advances in PRICP are reviewed to shed some light on the research focus in the future for the sake of in-depth study and wide application.

In order to investigate the effect of different carbon resource on enrichment of polyphosphate accumulating organisms (PAO) from sediment samples as well as the effect of PAO on the cycle of phosphorus in lake sediments, sedimentary samples in Lake Taihu were taken and enriched through using four kinds of carbon sources (glucose, cellulose, sodium acetate and propionate) in laboratory-scale sequencing batch reactors (SBRs). The COD/P ratio in the feeding was 15:1. The cycle time was 24 h and consisted of feeding, anaerobic period, aerobic period settle/decant period. The hydraulic retention time was 48 h, and the solids retention time was controlled at approximately 20 days. The dissolved oxygen concentration in aerobic period was maintained at 2-3 mg/L using an pump, where air was supplied at a flow rate of about 1 L/min. The reactor was operated at 25°C with an initial pH of 7.5 ± 0.1. The results showed that the orthophosphate concentration increased at the anaerobic phase in four reactors more or less, and decreased at the aerobic phase, which confirmed that there existed polyphosphate accumulating organisms in sediments of Lake Taihu. While phosphorus release rate using propionate as single carbon resource was the highest, acetate and propionate as substrate were benefit for accumulation of PAO.

This study investigated phosphorus removal in the rivers inputting into Lake Taihu, Jiangsu Province. Ecological community properties of aquatic plants and algae in those rivers were surveyed with focus on diversity and density. The results showed that total phosphorus (TP) concentrations decreased along the runoff in the rivers, and the river with balanced algae community and integrated water plants ecological system had the ability of retention and decontamination of non-point source pollutant-phosphorus. The current velocity and water level also affected self-purification efficiency of the river. It seemed that the rivers inputting into Lake Taihu acted as natural protective screen for pollutants flowing into lake, and natural rivers could be explored for phosphorus removal.