Low-level Wastewater Research Articles

Removal of radioactive material (Uranium-VI) from low level wastewaters and subsequent disposal of loaded biomass

The concentration of radioactive material i.e., Uranium, when disposed from nuclear reactor as low-level wastewater is under the limit value of 10 mg/l and concentration from mine tailing wastes is in the order of 10–100 mg/l. Biosorption is very cost-effective adsorption mechanism, discussed in this paper for removal Uranium (VI) from LLW using nonviable fungus called Ganoderma lucidum. Non-viable fungus has its advantage over viable fungus like for viable fungus one has to maintain temperature, pH and nutrient level. In this paper, the fungus called Ganoderma lucidum (GL) was used for sequestering uranium (VI) followed by studying their equilibrium and kinetics. Results show sorption rate is satisfactory, and data fitted a model of second order. Also, GL to be very effective biosorbent with 70 % of the total sequestration took place during the first 5 min for pure uranyl solution the corresponding specific uranium uptake rates being 0.106 mg/g-min at equilibrium concentration of 10 mg/L (Uranium VI) and pH maintained is 5. In this paper effect of competing co-ions were also studied and it is found out that effect of iron on uranium uptake is quite significant whereas the effect of other co-ions is at best marginal. Thus, biosorption by GL fungus is energy efficient and cost-effective method for removal of radioactive material from low level wastewater.

Near Field Simulation of Low Level Waste Water Released from Nuclear Power Plants in Rivers through Surface by CORMIX

CORMIX obtaining the approval from USEPA is widely used in the environmental evaluation of US inland nuclear power plants. Carry out 3-d simulation for the low level radioactive liquid effluent released from an inland nuclear power plant in rivers through surface by CORMIX. Compare the diluent effect of different discharge capacity (2 and 4 units) and different season (summer and winter). Dilution ratios of these four simulation conditions are all reach 10 at 500m downstream. The 0.1C0 isoconcentration line range of four units is much larger than two units. It is found from the concentration distribution of cross-section at 1km downstream that the diffusing vertically of effluent in summer is better than it in winter. The accuracy of the software will be confirmed by actual measurement.

Low-level waste waters desalted and purified by ionic membrane electrodialysis

Results obtained in a study of the possible application of electrodialysis to processing of low-level waste effluents are cited. It is shown that electrodialysis is applicable to purification fication of process slurries to a maximum permissible concentration (MPC)* where the solutions contain less than 100 mg/liter salts, and to desalting of more concentrated solu-tions. If the waste effluents contain more than 5 g/liter salts, a desalting process concurrent with isolation of alkali and acid present is recommended, with the alkali and acid recycled.