Abstract: According to the present invention, a fibrous material having a property to adsorb radioactive nuclides in the form of ion or molecule onto its surface is added to a cement type hydraulic solidifying material used for a solidifying material, a waste container, a structure in disposal site and a back-filling material used for production of a waste form of radioactive wastes, whereby improvement of long-term endurance of the waste form, the structure and the like and diminishment of leaching of radioactivity from the waste form and the like can be simultaneously attained.

Abstract: The present invention adds carbonates or chlorides of alkaline earth metals to the radioactive wastes containing sodium sulfate and subjects sulfate group in the radioactive wastes to reduction treatment, thereby converts the sulfate group into sulfides of alkaline earth metals which are chemically stable substances while suppressing SOx generation, and solidifies the radioactive wastes stably for an extended period of time by applying to the converted radioactive wastes solidifying treatment.

Abstract: The present invention relates to a method of cementing a radioactive waste and a cemented body thereof which are less liable to bring about radioactivity leakage for a long period of time and suitable for disposal of cemented bodies of radioactive wastes in the land.The radioactivity leakage from a cemented body of a radioactive waste occurs due to the presence of the voids within the cemented body, and these voids are formed during hardening of the cemented body or by leaching of a soluble component from the cemented body during immersion in water.In the present invention, in order to minimize the amount of radioactivity leakage, the fraction of fine voids (1 .mu.m or less) is limited to 20% by volume or less. In order to attain such a void fraction, operating conditions, such as water to cement ratio, hardening time of a mixture of a solidifying material with a waste, and addition of an organic polymer, are properly determined.Further, in order to prevent formation of a soluble component, i.e., Ca(OH).sub.

Abstract: A method of solidifying radioactive wastes comprising the steps of substituting the atmosphere inside a container packed with radioactive waste with a condensable vapor, pouring a matrix material into said container and thereafter condensing said vapor. The condensable vapor can be steam and the matrix material can be alkaline organic material.

Abstract: The present invention relates to a technique of concentrating waste water whereby the water content of the waste water is removed with a high decontamination factor, employs a porous membrane having a property allowing gas such as steam to permeate but not allowing a liquid such as water to do, as a membrane for concentrating the waste water, and adopts a method wherein the waste water is turned into a vapor flow and this vapor flow is made to contact the porous membrane so as for the waste water to be concentrated on the occasion when the waste water is to be concentrated by means of this porous membrane. By turning the waste water into the vapor flow, most of various metal ions, a surfactant, etc. existing in the waste water are separated from the vapor flow. Mist, metal ions in the mist and others contained in the vapor flow are removed by the aforesaid porous membrane from the steam while permeating the same.

Abstract: The present invention provides drying and pulverization of a radioactive liquid waste containing sodium borate as a main component by heating, where the liquid waste is heated, dried and pulverized to substantially crystalline, homogeneous powder of sodium borate while suppressing occurrence of a foaming phenomenon of the powder. The susbtantially crystalline powder is obtained by heating, drying and pulverizing the liquid waste at a temperature outside the temperature range where the salt powder takes an amorphous state in the course of releasing water of crystallization from the salt powder. In the drying and pulverization of a liquid waste containing sodium borate by a thin film evaporator, occurrence of the foaming phenomenon can be suppressed by maintaining the temperature on the heat transfer surface of the evaporator at a temperature lower than 150.degree. C.

Abstract: A process and an apparatus for cleaning nuclear reactor cooling water with cation exchange resin whose ion-exchanging groups have a bonding energy of not more than 300 KJ/mole are disclosed, whereby the radiation exposure of operators in an atomic power plant can be considerably reduced, and the waste ion exchange resin can be readily disposed.

Abstract: Electric conductivities of an aqueous solution under measurement are measured at two or more different temperatures in a range To to Tn, and a relationship between the electrical conductivity and the temperatures is obtained. A solute substance in the aqueous solution is determined by applying this relationship against a known temperature and electrical conductivity relationship of an individual substance. A concentration of the determined substance is estimated by applying the electrical conductivity at the lowest temperature To to a known relationship between an electrical conductivity and a concentration at the same temperature To with respect to an individual substance.

Abstract: A soluble salt (sodium sulfate or sodium borate (Na.sub.2 SO.sub.4 or Na.sub.2 B.sub.4 O.sub.7) contained as the main component in a concentrated radioactive waste liquid generated in the BWR power plant or the PWR power plant is insolubilized and precipitated, sodium hydroxide (NaOH formed in the insolubilization is separated from the precipitate and the radioactive waste liquid slurry containing the precipitate is solidified with a hydraulic solidifying material. Since the separated caustic soda (NaOH) is free of radioactive substances, it can be easily utilized again, and since the radioactive substances are stably fixed in the solidified body, leakage of radioactivity from the solidified body can be greatly reduced.

Abstract: A wax for thermal ink transfer, which consists essentially of a reaction product of an .alpha.-olefin having an average carbon number of from 16 to 100 with maleic anhydride, said reaction product having a weight average polymerization degree of from 1 to 100 and which has a heat of fusion of not higher than 40 cal/g.

Abstract: The process of the present invention comprises adding an alkaline earth metal hydroxide such as barium hydroxide to a radioactive liquid waste containing sodium sulfate as the main component to convert the latter into an insoluble alkaline earth metal salt such as barium sulfate, adding silicic acid to by-product sodium hydroxide to prepare water glass and solidifying the radioactive insoluble alkaline earth metal salt with the water glass. According to this process, exudation of radioactive substances from the solid can be prevented and the solid having a high durability can be obtained at a low cost.

Abstract: The low-temperature fluidity improver comprising(A) an adduct formed by adding a reaction product having the weight average polymerization degree of 1 to 100, which is prepared from an .alpha.-olefin having the average carbon atom number of 10 to 30 and maleic anhydride, to an aliphatic alcohol having the average carbon atom number of 6 to 28, in which the sum of the average carbon atom number in the longest alkyl group chain of the .alpha.-olefin and the average carbon atom number in the longest carbon chain of the aliphatic alcohol is 22 to 40, and/or a salt of said adduct, and(B) a low molecular weight polyethylene having the numerical average molecular weight of 500 to 20,000 and/or a reaction product thereof with maleic anhydride.

Abstract: An apparatus for cutting an insulated wire, stripping the end thereof and twisting the wire strands, comprises an insulated wire intermittent supply, cutting blades to be driven to cut the wire during the stoppage of the wire supply and to be returned immediately thereafter. Front and rear stripping blades are driven to cut only the insulation of the wire at positions spaced forwardly and rearwardly of the wire cutting position. Front and rear insulation rotating bars are driven to contact the insulation forward and rearward of the wire cutting position and to move in the opposite directions to rotate the insulation thereof while the wire portions at the opposite sides of the wire cutting position are forcibly drawn in the directions away from the wire cutting position.

Abstract: An apparatus for cutting an insulated wire, stripping the end thereof and twisting the wire strands, comprises an insulated wire intermittent supply, cutting blades driven to cut the wire during the stoppage of the wire supply and returned immediately thereafter. Front and rear stripping blades are driven to cut only the insulation of the wire at positions spaced forwardly and rearwardly of the wire cutting position and returned after a predetermined period after return of the cutting blades. A pair of front insulation rotating bars are driven to contact the insulation rearward of the front insulation cutting position and moved in the opposite directions to rotate the insulation thereof while the cut wire length is forcibly moved in the supply direction thereof, whereby the end of the cut wire length is stripped and the strands thereof are twisted.