Indonesia’s Local Material Effect in Clay-Based Ceramic Filter Fabrication as an Alternative for Liquid Radioactive Waste Processing Material

The solid waste plant at Harwell in Oxfordshire, contains a purpose built facility to input, assay, visually inspect and sort remote handled intermediate level radioactive waste (RHILW). The facility includes a suite of remote handling cells, known as the head-end cells (HEC), which waste must pass through in order to be repackaged. Some newly created waste from decommissioning works on site passes through the cells, but the vast majority of waste for processing is historical waste, stored in below ground tube stores. Existing containers are not suitable for long term storage, many are already badly corroded, so the waste must be efficiently processed and repackaged in order to achieve passive safety. The Harwell site is currently being decommissioned and the land is being restored. The site is being progressively delicensed, and redeveloped as a business park, which can only be completed when all the nuclear liabilities have been removed. The recovery and processing of old waste in the solid waste plant is a key project linked to delicensing of a section of the site. Increasing the operational efficiency of the waste processing plant could shorten the time needed to clear the site and has the potential to save money for the Nuclear Decommissioning Authority (NDA). The waste processing facility was constructed in the mid 1990s, and commissioned in 1999. Since operations began, the yearly throughput of the cells has increased significantly every year. To achieve targets set out in the lifetime plan (LTP) for the site, throughput must continue to increase. The operations department has measured the overall equipment effectiveness (OEE) of the process for the last few years, and has used continuous improvement techniques to decrease the average cycle time. Philosophies from operational management practices such as ‘lean’ and ‘kaizen’ have been employed successfully to drive out losses and increase plant efficiency. This paper will describe how the solid waste plant at Harwell has continuously increased the throughput of RHILW, which should lead to significant programme savings.

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Immobilization of NPP evaporator bottom high salt-bearing liquid radioactive waste into struvite-based phosphate matrices

Journal of Hazardous Materials ◽

10.1016/j.jhazmat.2021.125902 ◽

2021 ◽

Vol 416 ◽

pp. 125902

Author(s):

Oleg A. Kononenko ◽

Vitaly V. Milyutin ◽

Vadim I. Makarenkov ◽

Evgeny A. Kozlitin

Keyword(s):

Radioactive Waste ◽

Liquid Radioactive Waste ◽

High Salt

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Influence of acid-base and oxidation-reduction reactions on the distribution of stable impurities and radionuclides in “soil-liquid radioactive waste” system

Czechoslovak Journal of Physics ◽

10.1007/s10582-003-0080-1 ◽

2003 ◽

Vol 53 (S1) ◽

pp. A621-A627

Author(s):

A. S. Kozyrev ◽

V. A. Matyukha ◽

E. N. Semyonov ◽

V. K. Larin

Keyword(s):

Radioactive Waste ◽

Liquid Radioactive Waste ◽

Acid Base ◽

Reduction Reactions ◽

Oxidation Reduction

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Influence of Geopolymer Binder Components on Properties of Compounds during Cementation of Boron-Containing Liquid Radioactive Waste

Nuclear Power and the Environment ◽

10.31717/2311-8253.21.2.7 ◽

2021 ◽

Vol 21 (2) ◽

pp. 71-77

Author(s):

Yu. G. Fedorenko ◽

◽

Yu. A. Olkhovyk ◽

A. N. Rozko ◽

G. P. Pavlyshyn ◽

...

Keyword(s):

Radioactive Waste ◽

Liquid Glass ◽

Potassium Hydroxide ◽

Linear Equations ◽

Liquid Radioactive Waste ◽

Correlation Coefficients ◽

Component Composition ◽

Normative Values ◽

Leaching Rate ◽

Base Compound

The paper presents an analysis of the experimental results of the use of geopolymer binders for cementing boron-containing liquid radioactive waste (LRW). The dependence of the properties of compounds on the component composition of binders has been studied. The following components are considered: liquid glass with a silicon modulus of 2.9, a mixture of ash of Darnytsya TPP with slag of the Mariupol metallurgical plant in a ratio of 1: 1 and potassium hydroxide. To perform a factor analysis of the effect, the mass of these substances was taken as three factors in the analysis at two levels. For the manufacture of compounds imitation LRW was mixed with zeolite in a ratio of 10:1 at a temperature of about 60 оC. Subsequently, the above components were added to the mixture, the weight of which varied by ±17% relative to the weight of the base compound. To study the properties, samples of different sizes 5×5×5 cm, 1.5×1.5×1.5 cm and rectangular samples with an outer surface from 96 cm2 to 104 cm2 were made. Each property was studied in 8 samples. The obtained results allowed to construct linear equations that quantitatively link the corresponding characteristic of the compound with the composition of the binders. The correlation coefficients between the experimental and the data calculated by the equation are estimated. The average values of the correlation coefficients may indicate that not all factors were taken into account. The obtained regularities show that in the conditions of the experiment slag and ash increase, and liquid glass and potassium hydroxide reduce the rate of setting of the samples. The density of the samples is increased by ash and slag, while liquid glass and potassium hydroxide are reduced. The compressive strength of liquid glass and potassium hydroxide is reduced, while the mixture of ash and slag is increased. The leaching rate Сs of liquid glass and potassium hydroxide is increased, the mixture of ash and slag is reduced. At the same time, the leaching rate of Sr increases the ash/slag mixture, while liquid glass and potassium hydroxide decrease. The time during which the leaching of Cs reaches the normative values, slag and ash are reduced, and liquid glass and potassium hydroxide are lengthened. The obtained results can be taken into account when optimizing the composition of geopolymer binders for cementing LRW.

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