A lot of forest-biomass exists on the steep mountain in Japan. However, it is very difficult to obtain the forest-biomass like brushwood, from the deep mountain to human habitation. Using by chute, brushwood can be transported automatically if we can keep an appropriate slope gradient. The most important point is a repose angle of chip on the slope. These angles are strongly depending on the figure of chip, the aspect ratio, and the surface roughness of the chute bed.

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In resource-starved Japan, sea water resources have attracted attention until now. However, there is no utilization example technology except for a salt and water. It is apprehensive about resource reservation becoming difficult in the near future. Then, it is required to investigate the integrated utilization technology of sea water and brine-concentrate resources in detail. In this report, the following five contents were mainly investigated. (1) Evaluation of concentrated brine produced by desalination process. (2) Re-consideration of the resources which dissolved in sea water. (3) Reappraisal of the production economy of the resources which dissolved in sea water and brine-concentrate and investigation of the high-value-added technology of the chemical compounds originating in the resources which dissolved in sea water. (4) Combination with salt and bitten treatment processes. (5) Proposal of integrated utilization process for sea water and brine-concentrate resources.

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There are growing needs for seawater desalination plants all over the world in order to secure stable water resources. Hitachizosen has seawater desalination technologies for three processes (MSF, MED and RO). A significant amount of research and development (R&D) has been carried out in order to constantly improve the technologies and reduce the cost of desalination. This paper describe the features of the processes, overviews of our recent R&D activities and future trends in thermal seawater desalination technologies.

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The technology of snow-utilization is consisted with (i)gathering snow and transportation, (ii) storing and (iii) snow using such as cold heat source. In the field of the gathering and the transportation of the snow(i) , the heavy equipment machine such as the rotary type snowplow that have already used it in the snow-removal work is diverted and used. Because energy density of snow to be low, and, therefore, it has low economical value. Even if it is not too big power, the snow is easily transformed into a clod. Therefore, the use of transportation snow with air (solid-air two-phase flow) has been limited to the minimum in the popular snow machines of such as the rotary type snowplow. Therefore, there is few case to use the solid-air two-phase flow in the field of the gathering and transporting the snow (i) and (ii). However, the multi-phase flow plays an important role in the use of the snow like the extraction of cold heat from the snow in the fields of (iii). It is because a lot of movements of vapor and droplets of water are used at the same time in the heat exchanging between the snow and air. In this paper, the author described an introduction of the snow utilization technology necessary to talk about the multi-phase flow related to the snow utilization, the example of the multi-phase flow in the field of the snow utilization, and described the views of them.

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Groundwater is one of the most important water resource for many country, and adequate management is required to use it sustainably. Modeling and simulation are the strong tool for groundwater management. However, hydraulic conductivity distribution of the flow field has been ig.nored in the most of simulations. In this report, the outline of the model for spatial distribution of hydraulic conductivity is described, and some examples of the numerical simulations in the non-uniform flow field are introduced.

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