Uranium behavior in the process of ashing the wood base of spent chemical absorbers

The results of investigating the wood base ashing of spent chemical absorbers of MW and MMW types containing uranium have been given. The acceptable ashing temperature has been shown to be equal to 600–700°C, with a process duration of no less than an hour. To decrease the volume of the ash residues, a crushing stage is required. The volume of the ash residues comprises 6–10% of the volume of source absorbers; furthermore, their mass decreases threefold depending on the uranium content in the source material. Ways to decrease the temperature of the wood base ashing, including those that use burning promoters, have been contemplated.     

Removal of low-volatile impurities from magnesium by sublimation

The sublimation refining of magnesium with initial Fe, Ni, Cu, Si, and Al contents from ～10^?3 to 10^?2% at temperatures from 700 to 800 K with a 80% degree of distillation reduces the impurity concentrations by one to two orders of magnitude in the first process and by an additional order of magnitude in a second cycle. The effective separation factor α found using the main distillation equation is on the order of 10 for the impurities and processes in question.     

Mathematical model of the fibre laydown mechanism with a single-channel helical reel and reversing yarn guide

Conclusions The mathematical model examined permits one to do the following: perform a complex study of the high-speed yarn laydown mechanism; determine the kinematic and dynamic parameters of the mechanism; determine the optimum geometric dimensions of the yarn guide.Translated from Khimicheskie Volokna, No. 3, pp. 11–13, May–June, 1989.