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Incinerating the radioactive sludge that has piled up at sewagefacilities across eastern Japan and burying it after mixing it withcement could increase the risk of cesium seeping into theenvironment, scientists say. Disposal of the sludge, which is thought to have been created afterradioactive materials from the Fukushima nuclear disaster werecarried by rainwater into sewage pipes and then condensed duringsewage treatment, has become a major headache for localgovernments. One solution, being pursued by local governments, is incineratingthe sludge and then mixing it with cement before burying it inlandfill sites. But the results of a research team led by Hideo Yamazaki, aprofessor of environmental analysis at Kinki University, suggestthe process may increase the risk of the transfer of radioactivecesium into the environment. Instead, the scientists found thatadding clay to the incinerated material may offer a safer way ofprocessing it. The researchers added a small amount of rainwater to radioactivesoil from Minami-Soma, Fukushima Prefecture, as well as the ashgenerated by incinerating the soil. They measured the extent ofradioactive cesium transfer into the water after stirring themixtures for two hours. No cesium was transferred from the radioactive soil into the waterwhen raw soil was used, but 0.11 percent of the cesium passed intothe water when water was added to incinerated soil. The transfer rate soared to 2.87 percent when cement was added. Theaddition of clay suppressed the transfer. When contained in unprocessed soil and sewage sludge, the cesiumappears to bond strongly with the soil s clay component and thereis little seepage. Incineration allows more cesium to drift awaybecause it breaks up the clay. The addition of alkaline cementapparently further assists the flow of cesium, the scientists said. Currently, many local governments across eastern Japan are storingash at sewage disposal facilities because they have nowhere else toput it. The Tokyo metropolitan government is burying it in landfillsites after mixing the ash with cement and water. According to central government safety standards, incineratedsludge and soil can be put in landfill sites if it contains 8,000becquerels or less of radioactive cesium per kilogram. I am an expert from multifunction-calibrator.com, while we provides the quality product, such as Socket Tester , Digital Clamp Meters Manufacturer, RTD Calibrator,and more.
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