Kovács Tibor, Shahrokhi Amin, Sas Zoltán, Vigh Tamás, Somlai János
Institute of Radiochemistry and Radioecology, University of Pannonia, 10 Egyetem Str., H-8200, Veszprém, Hungary; Social Organisation for Radioecological Cleanliness, 7/a József Attila Str., H-8200, Veszprém, Hungary.
Institute of Radiochemistry and Radioecology, University of Pannonia, 10 Egyetem Str., H-8200, Veszprém, Hungary.
J Environ Radioact. 2017 Mar;168:15-20. doi: 10.1016/j.jenvrad.2016.07.014. Epub 2016 Jul 21.
The reuse of by-products and residue streams is an important topic due to environmental and financial aspects. Manganese clay is a residue of manganese ore processing and is generated in huge amounts. This residue may contain some radionuclides with elevated concentrations. In this study, the radon emanation features and the massic exhalation rate of the heat-treated manganese clay were determined with regard to brick production. From the manganese mud depository, 20 samples were collected and after homogenization radon exhalation characteristics were determined as a function of firing temperatures from 100 to 750 °C. The major naturally occurring radionuclides K, Ra and Th concentrations were 607 ± 34, 52 ± 6 and 40 ± 5 Bq kg, respectively, comparable with normal clay samples. Similar to our previous studies a strong correlation was found between the internal structure and the radon emanation. The radon emanation coefficient decreased by ∼96% from 0.23 at 100 °C to 0.01 at 750 °C. The massic radon exhalation rate of samples fired at 750 °C reduced by 3% compared to samples fired at 100 °C. In light of the results, reusing of manganese clay as a brick additive is possible without any constraints.
由于环境和经济方面的原因，副产品和残余物流的再利用是一个重要的课题。锰泥是锰矿石加工过程中产生的一种残渣，产量巨大。这种残渣可能含有一些浓度较高的放射性核素。在本研究中，针对砖生产测定了热处理锰泥的氡析出特性和质量析出率。从锰泥储存库中采集了20个样品，均质化后测定了100至750°C焙烧温度下的氡析出特性。天然存在的主要放射性核素K、Ra和Th的浓度分别为607±34、52±6和40±5 Bq kg，与正常粘土样品相当。与我们之前的研究类似，发现内部结构与氡析出之间存在很强的相关性。氡析出系数从100°C时的0.23下降到750°C时的0.01，降幅约为96%。750°C焙烧的样品的质量氡析出率比100°C焙烧的样品降低了3%。根据这些结果，将锰泥作为砖添加剂进行再利用是可行的，没有任何限制。
