In the sustainable society, the recycling of resources should achieve the preservation of regional and global environment and should be coordinated with regional agricultural and industrial activities. Especially for waste biomass resources, it will be supplied or discharged by multiple industries as agriculture, forestry, fisheries, manufacturing, commerce and living, and will be demanded by multiple purposes as foods, supplements, feeds, fertilizers, industrial materials and fuels. Therefore, waste biomass flows connecting these supplies to demands will be extremely complex. In order to judge the effectiveness of introducing technologies for recycling, a comprehensive framework, which can estimate impacts of technologies on regional material cycles and regional and global environment, is need. For this purpose, we are developing a physical input-output table (PIOT) for describes complex material flows of waste biomass, water and their constituents (e.g. carbon, nitrogen and phosphorus) in a region by integration of quantity data. This PIOT sets not only industries but also activities on recycling, waste disposal and wastewater handling in detail as sectors. Import and export between regions, and emissions to environment are also set in the table. Applying content rates of carbon, nitrogen and phosphorus to mass flows of each item, elemental flows of those are accounted for estimating emission to water (as organic pollutant and nutrients) and atmosphere (as greenhouse gas) from the whole system. The energy consumed by activity in each sector is also accounted for estimating greenhouse gas emission. Another originality of this PIOT is that physical data obtained from relevant statistics will be directly integrated to values in the table. As a case study, we are surveying the waste biomass flow at the Kochi prefecture, Japan. Administrative information on industrial waste was acquired from the Kochi Prefecture and the Kochi City with their cooperation. For municipal waste, annual survey on municipal solid waste business by the ministry of the environment was used. For by-product, generation amount, sort, composition and usage of biomass waste were surveyed by hearing, sampling and questionnaire at recyclers of biomass waste. Amounts of generation, recycling and disposal of each biomass waste item, disposal method and municipality were built up from these reports and survey. Using above information, flows of each lot (the annual generation an item of waste from a source) of biomass waste from generation via treatment to disposal or reuse were compiled in the database and set into the PIOT. The current biomass PIOT for Kochi Prefecture is shown in Figure. This table shows weight of materials as wet basis. The 1.43 × 108 tons/year of total demand and the 1.34 × 108 tons/year of total supply were accounted at this time. The difference between demand and supply would mainly be resulted from unrecorded flows in our database, especially on supply of water from the waterworks and the natural water, and the biomass production. We will survey constituents of carbon and nutrients in materials and expand our PIOT to depict the substance flows of elements, in order to estimate quality and quantities of emissions.

Stabilization of landfill gas (LFG) generation is recognized as the critical indicator to evaluate the future possibility of environmental impact from the waste landfill. In comparison with leachate quality, the amount of LFG generation is considered more difficult to integrate the sequential monitoring results. Spatially and temporal high variation of the LFG generation and the emission would be influenced by the micrometeorological condition. One of the helpful information to predict the behavior of LFG generation is to estimate the remaining of LFG source in the waste. Biological degradation should decrease the amount of component that should be transformed LFG in the waste. Hence, the LFG generation potential of waste in landfill must be gradually decreased as time goes on. In order to support the assessment of the landfill stability from the viewpoint of LFG, the estimation of the potential of LFG generation of the landfilled waste has been investigated at the landfills that was received the waste incineration ash, slag, C&D inert residue, dredged soil, and so on. The LFG emission behavior has been predicted by using the remaining LFG potential, and it was validated by the investigation of surface LFG emission. Degraded organics by anaerobic incubation had been calculated by Buswell's theoretical equation (Bockreis, et al. 2007). Objected samples that were excavated from 10-15 years old waste layer have shown the little potential of LFG generation (Table 1). A highest content of gasified organics was observed for 2.0m depth of C10 though it was less than 1% of the total weight of sample (dry weight). It would be strongly attributed to intensive pretreatment of waste before the landfilling. Since the landfill operator required the strict quality control for the waste to be disposed of, the content of organics in the waste should be enough low at the initial phase of landfill management. In addition, the effort of the landfill management to promote the biodegradation, such as the lowering of the water level in landfill layer, or ventilation of LFG, had contributed to reduce the biodegradable organics. Fig.1 shows the prediction of methane emission from the landfill. It also exhibited results of investigation of surface LFG emission. The prediction of landfill methane emission was developed by using the parameter that was obtained from excavated waste.

Prediction method for the long-term chemical leaching amount from by-product/recycled materials such as waste concrete and steel slag and so on is necessary to widely promote their effective utilization and evaluate their environmental safety. Although there are the batch leaching tests and the column leaching test as the testing methods for evaluating the long-term leaching behavior, the leaching mechanism and the testing result compatibility in both tests has insufficiently been clarified yet. Thus, the prediction of the leaching behavior from the by-product/recycled materials used in actual civil works and their environmental safety evaluation are by no means certain. This paper shows the difference between the batch leaching tests and the column leaching tests in the chemical leaching behavior of Cu-slag. The batch leaching tests were conducted under liquid/solid ratio = 10, liquid = distilled water, stirring strength = 0, 30, or 120 rpm. After a certain elapsed time, the leaching solution was exchanged with the pure distilled water and then the stirring was restarted. The elapsed time was set at 1, 2, 4, 8, 16, 32 days. The column leaching tests were also conducted under the same conditions as those of the batch leaching tests in order to evaluate the effects of the pore distribution and the pore flow velocity in the Cu-slag column on the leaching behavior. In the column leaching tests, the effluent passing through the column was circulated as the influent (Fig. 1). The leaching duration in the column tests can be equivalent as that in the batch tests, so that the difference in the leaching behavior between the batch leaching tests and the column leaching tests may be dependent on the pore-scale heterogeneous flow and path generated in porous materials. Figure 2 shows the leaching rate evaluated from the batch leaching tests and the column leaching tests. In the same fluid velocity levels, the leaching rate in the column tests was larger than that in the batch tests. The leaching rate has been considered large with the fluid velocity. Although the fluid velocity generated by the stirring was the same as the flushing velocity on the surface of the Cu-slag in the batch tests, the fluid velocity in the column tests was enhanced because the permeant liquid was concentrated into the limited pore space in the Cu-slag column. Thus, the pore-scale heterogeneous flow and path generated in porous materials should be evaluated in order to clarify the compatibility between the batch leaching tests and the column leaching tests.