Bobsleigh and Luge Track of the Nagano Winter Olympic Games which will be held in February 1998 is the 14^th one in the world as a system of chilling and icing the entire track with refrigerators. The Nagano's system is the first one in the world as a system of indirectly chilling the track by using brine which is ethylene glycol. The system of the other tracks is a system of directly chilling by expanding ammonia. Mitsubishi Heavy Industries, LTD (MHI) has designed and constructed an ideal ice making system which had refrigerators, pumps, a cooling piping, an automatic control system, and MHI original Distributed Control System (DCS) by thermal dynamic simulation of the track. Optical communication was applied to the DCS in order to connect to thirteen control stations, which were located along the track 1.7km in length. Applying optical communication to the DCS, MHI realized the reliable DCS with anti-electromagnetic interference against, for example Lightning.

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These days, it becomes serious problem how to dispose the waste in Japan. The waste is mainly filled in the landfill after to be crushed or incinerated. Now, capacity of the landfill is estimated to be less than ten years.
It is often the case that plastics waste is filled directly in the landfill because the plastics waste has high calorific value and damages the incinerator. This becomes a fac-tor of a shortening the landfill capacity.
This paper discribes the effect of introduction of actual disposal technologies for plastics waste on the landfill capacity in the short and middle term. For the case of Tokyo, we tried preliminary estimation of economical inpact for the case of energy recovery as electricity by burnning up the plastics waste, and for the case of filling all waste.
As a result, energy recovery and filling system was found to be good way for dis-posal of plastics waste in the short and middle term. And the system is more profitable way than the present way of filling without combustion.

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Ultra fine particles of Fe, Ni, Co and Mo with diameter of 5-20 nm were synthesized. The particles were stable under the atmosphere because they were surrounded with graphite sheet and amorphous carbon. Catalytic activities of them for hydrogenation of 1-methyl naphthalene were tested. It was found that ultra-fine particles of Ni-carbon composite had high catalytic activities. The kinetic analysis shows that more active hydrogenation catalysts can be prepared by bi-metallic clusters.

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100 samples of recycle solvent were obtained by continuous operation (50 days) of 1 ton/day coal liquefaction plant at Kimitu. Naphthalene derivatives in the recycle solvents were anslyzed in detail by the technique of selective ion measurement of GC/MS. Accordingto the replacement of the initial solvent by coal-derived products, the carbon number of alkyl side chain of the naphthalene derivatives in the recycle solvent became larger as well as structures of the alkyl side chains changed from poly methyls to longer chains. The ability of hydrogen donor of alkyl-tetralins/indanes depended on the carbon numbers of alkyl side chain: increase in carbon numbers decreased the ability of hydrogen donor.

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Secondary pyrolysis of coal tar produced from commercial coke oven was performed with a flow reactor at 700-900°C for 5-22 s and the effects of reaction conditions on the products yields and the composition of the light fraction has been investigated. The products were separated by solvent extractions into HS (hexane soluble), HI-CFS (hexane insoluble-chloroform soluble), CFI-THFS (chloroform insoluble-tetrahydrofuran soluble) and THFI (tetrahydrofuran insoluble=coke). The yield of HS decreased and that of THFI increased remarkably at 800 and 900°C. The HS fractions were analyzed by glass-capillary column gas chromatography equipped with a flame ionization detector. The HS fraction was made up of unsubstituted, alkyl-substituted and hydrogenated derivatives of polycyclic aromatic hydrocarbons (PAHs), heterocyclic and aliphatic compounds. It was found that the conversions of substituted PAHs and heterocyclic compounds containing oxygen and nitrogen, such as dibenzofuran and quinoline, increased remarkably at 900°C, and most part of these compounds disappeared in 13 s. Further, naphthalene which was considered as a most stable compound in unsubstituted PAHs in HS fraction also converted remarkably into the condensed compound at 900°C.

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It is necessary to introduce energy cascade systems into the industrial sector in Japan. The aim of this study is to evaluate the energy conservation potential of introducing both energy cascade networks and thermal recycling systems in industries located around urban area. The following industries are thought to be connected to an integrated energy center: rolling copper, printing, bakery, integrated circuit, pharmacy, dairy and refrigerated warehouse. The authors have developed an energy cascade model based on linear programming so as to minimize the total fuel consumption.
Simulation results clearly demonstrate remarkable effectiveness of the energy cascade systems. Energy cascading saves up to 22% of energy demand in the above mentioned sectors. Co-generation systems can enhance energy cascade systems because they supply both heat and electric power at the same time. Increasing the amount of garbage combustor waste heat can reduce electric power for. the turbo refrigerator by promoting waste heat driven ammonia absorption refrigerator.

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The effect of preheating conditions on the liquefaction reaction of Victorian brown coal (Yallourn) was investigated using a process development unit (PDU) with three stirred tank reactors and three preheaters connected in series. Four kinds of solvents (RS, RS +CLB, RS+HDAO and RS+CLB +HDAO) were used for liquefaction to examine the relationship between the solvent properties and the effect of the preheating conditions. RS, CLB, HDAO were the recycled solvent fraction (b. p.180-420°C), heavy liquefaction product derived from the brown coal (coal liquid bot-tom, b. p.>420°C) and coal liquid product further hydrogenated over Ni-Mo catalyst (b. p.<250°C), respectively. For all experiments, the liquefaction was carried out in the presence of iron-sulfur catalyst (Fe₂O₃, S/Fe atomic ratio 1.2) under the conditions of temperature 450°C and pressure 14.7 MPa.
When the feed slurry was preheated up to 410°C for- 2 min. with hydrogen gas of 10 wt. % on daf coal, the distillate yield (b.p.<420°C) decreased 5-13 wt.% on daf coal for all kinds of the solvent in comparison with the case where reaction at the pre-heating stage was negligible. The decrease in the distillate yield resulted from the sup-pression of the conversion of the heavy fraction (CLB) into the solvent fraction (180-420°C). At the preheating stage, CO₂ and H₂O evolved and the coal of 20-30 wt % converted to preasphaltenes (benzene insoluble-pyridine solubles). The oxygen-contain-ing functional groups decomposed rapidly at more than 350°C, resulting in the formation of many radicals in the coal (Plorg.). Since the greater part of the coal remained as pyridine insolubles (Plorg.), the retrogressive reaction caused by the radicals in the Plorg. was considered to reduce the conversion of the heavy fraction into the distillate at the liquefaction stage.
Based on these results, it is concluded that the usual preheating conditions of the liquefaction process decreased the liquedaction performance. This indicates that the distillate yield increases if the retrogressive reaction at the preheating stage is suppres-sed by controlling the preheating conditions and solvent quality such as hydrogen donor ability and catalyst activity.

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