Principles and plant system desingns of nuclear fusion power is described introductively. Taking mainly the D-T reaction as the most feasible reaction expected to be of practical use in near future, development status of fuel cycle processes of fusion reactor, such as fuel injection, separation of tritium from discharged plasma gases, production and recoveery of tritium in blanket, is reviewed. Since the burnup fraction per pass of injected tritium fuel will be only a few precent, it is important to recover unused tritium from discharged gaseous mixtures with very high recovery yield. Recovery processes, which are considered to be feasible, are palladium film permeation, diffusion-effusion, metal-sponge adsorption, laser method, oxidationelectro lysis, and cryogenic distillation method. For separating tritium produced in lithium metal blanket and lithium molten salt blanket, there seems to be several methods sucn as metalwindow method, molten salt extraction, heat-pipe method, lithium-getter method, gas sparging method and cold-trap method. Some feasible processes to recover tritium from potassium and helium coolants are also discussed. These include metal-window, solid adsorber, and cold trap and oxidation methods.
Then, significance of fusion energy as an alternative for the basic energy supply resources are compared with the other resources, such as fission and fossil fuels. In addition, it is noted that some artificial production of fairly large amount of tritium will be required for initial charge of fuels for developmental and first generation fullscale fusion reactors.
Finaly, regarding the safety and environment problems of fusion power reactors, production and release of radioactivity, especially of tritium, are examined for both situations of normal operation and design basis accident.

抄録全体を表示

High Temperature Gas Cooled Reactor (HTGR) fueled with fully enriched uranium and thorium, is expected to show a better fuel performance and will reduce the consumption of uranium resources to a large extent. The best use of thorium and bred fuel, uranium-233, can be achieved by the coated particle fuel, as the contamination of recovered U-233 with U-236 and U-238 is limited to a low level while uranium particles and thorium particles are homogneously mixed in a fuel rod.
The unique feature of HTGR fuel structure requires to innovate spent fuel reprocessing techniques. In particular, completely different head and process from that for light water reactor fuels has to be developed. Crush-burn-leach and off gas treatment techuiques are beingdeveloped in U. S. A. under a government sponsored program. Tritium and noble gases can be removed efficiently through the techniques. From the environmental safety stand point, it is an important advantage for the HTGR fuel reprocessing.

抄録全体を表示

Full scale dry limestone injetion tests were carried out in cooperation with Central Research Institute of Electric Power Inustries and Chubu Electric Power Company at the No .8 boiler in Meiko Power Station and at the No .3 boiler in Mie Pawer Station.
From those two field tests, the results are obtained as follows.
(1) From the ratio of reacted lime (R_t) in the pilot furnace tests, the ratio in boiler (R_p) will be given in next.
R_p= A·B·R_t (D_t/D_p) ^0.3 ((SO₂) _p/ (SO₂) _t) ^0.4
(2) Sulfur dioxide removal in boilers will be given as the sum of sulfur dioxiide removal by deposited lime and the products of the ratio of reacted lime and the amount of injected limestone.
(3) Sulfur dioxide removal by deposited lime increased with the increase in deposition. But itwill cause troubles in boiler operation.
(4) We found that the hydrated sorbents recovered in precipitator will give the same sulfur dioxide removal as the new limestone when the hydrated sorbents are reinjected into boilers.

抄録全体を表示

The purpose of this work is to examine the tensile strength of coke and to relate this to the properties of industrial coke.
The indirect tensile test (I. T. T .) provides an experimentally simple method for ensuring tensile strength of brittle materials . It is based on the theory of stressed beams and use test specimens fabricated into rods rectangular section.
The theory indicates that I. T. T. is the most suitable method for measuring strength of formed coke. But as th first step of the study the blast-furnace coke is cosidered in this paper.
The experiment with blast-furnace coke specimens indicated breakage strengths between 5 and 120kg/cm², average 40kg/cm².
It was concluded that although the tensile strength of industrially acceptable blast frunace cokes can vary widely the measurements correlate well with the micro strength which represents caking power, and tnat the distinct influence of apparent density of the cokes (determined from tneir weight and dimensions) upon their tensile strength.

抄録全体を表示

In order to get better yield of fusible matter from pitches containing QI matter because fusibility is necessary for the carbon precursor to be anisotropic needle cokes, some trials of modification have been investigated. QI matter of petroleum pitch (Kureha pitch) was compared with that of coal-tar pitch about their reactivity, solubility, and fusibility after modification. Reductive alkylation by the aid of potassium gave the soluble matter in benzene in the yield of 60 % from KP-QI, however, the matter was infusible. In contrast, hydrogenation by the Birch reduction gave fusible matter which was soluble in chloroform, although the yield was only 15 %. The yield of fusible matter reached up to 70% by combining two modification treatments. The reaction against the unfractionated pitch increased the yield, perhaps because KP-QS may work as the solvent for these reactions. The catalytic hydrogeantion of alkylated QI using heterogeneous catalysts under hydrogen pressure was also tried. Alkylation and acylation by Friedel-Crafts reaction were found to give good yield of benzene soluble matter, which was infusible. Carbonization properties were related with the modification method by investigating the carbonization process of these modified pitches through the analysis of evolved gases and decreasing rates of H/C ratio.

抄録全体を表示