This paper evaluates the efficacy of magnesium potassium phosphate cements (MKPCs) as waste forms for the solidification of radioactive concrete powder wastes produced by the decommissioning of nuclear power plants. MKPC specimens that contained up to 50 wt% of simulated concrete powder wastes (SCPWs) were evaluated. We measured the porosity and compressive strength of the MKPC specimens, observing them using scanning electron microscopy and X-ray diffraction. The addition of SCPWs reduced the porosity and increased the compressive strength of the MKPC specimens. Struvite-K crystals were well-synthesized, and no additional crystal phase was formed. After thermal cycling and after immersion, MKPC specimens with 50 wt% SCPWs satisfied the waste-acceptance criteria (WAC) for compressive strength. Semi-dynamic leaching tests were performed using the ANS 16.1 method; the leachability indices of Cs, Co, and Sr were 11.45, 17.63, and 15.66, respectively, which also satisfy the WAC. Thus, MKPCs can provide stable matrices to immobilize radioactive concrete wastes generated by the decommissioning of nuclear power plants.

本文评估了磷酸镁钾水泥 (MKPC) 作为废物形式固化核电厂退役产生的放射性混凝土粉末废物的功效。对含有高达 50 wt% 的模拟混凝土粉末废料 (SCPW) 的 MKPC 试样进行了评估。我们测量了 MKPC 样品的孔隙率和抗压强度，并使用扫描电子显微镜和 X 射线衍射对其进行了观察。SCPW 的添加降低了 MKPC 试样的孔隙率并提高了抗压强度。鸟粪石-K 晶体合成良好，没有形成额外的晶相。在热循环和浸泡后，具有 50 wt% SCPW 的 MKPC 样品满足抗压强度的废物接受标准 (WAC)。使用ANS 16.1方法进行半动态浸出试验；Cs、Co 和 Sr 的可浸出性指数分别为 11.45、17.63 和 15.66，也满足 WAC。因此，MKPC 可以提供稳定的基质来固定核电厂退役产生的放射性混凝土废物。