Hiroshi Yagita

CO2 emission reduction for Japanese petrochemicals

Energy efficiency in the Japanese industry is one of the highest in the world. As a consequence, reduction of CO2 emissions is considered to be difficult and costly. However little attention has been paid as of yet to changes related to so-called non-energy use of fossil fuels. The analysis in this paper suggests that a large number of options exist for emission reduction in the Japanese petrochemical industry. This includes the introduction of biomass feedstocks, the introduction of new catalytic production processes, and changes in waste handling. The use of bioplastics and the use of CO2 feedstocks seem costly options for GHG emission reduction that should not be applied on the short term. Japanese GHG emissions can be reduced by 7.7% if the optimal set of emission mitigation options is applied. About 60 Mt emission reduction (4.9%) can be achieved by changes on the supply side, another 35 Mt emission reduction (2.8%) can be achieved by changes in waste management. While changes in waste management can be implemented before 2010, biomass introduction on the supply side will probably require a longer lead-time. About half of the emission reduction is cost–effective, but will require further technology development. The other half can be achieved at a cost level of 10,000 yen/t CO2 (80 US

Assessment of CO 2 Emission Reduction Strategies for the Japanese Petrochemical Industry

/t CO2). The latter part is based on proven technology that is currently not cost–effective.

Outflow of Resources from Japan Focusing on End-of-Life Vehicles

: This article analyzes the possibilities for reducing carbon dioxide (CO2) emissions in the life cycle of Japanese petrochemicals, focusing primarily on the nonenergy use of fossil fuels. For this purpose a linear programming model called CHEAP (CHemical industry Environmental strategy Analysis Program) has been developed. The results show a moderate autonomous growth of emissions by 5% in the period 2000 to 2020, if it is assumed that no new technology is introduced and demand (measured in physical units) increases 1% per year, on average. However, if it is assumed that ongoing technology development succeeds, emissions in 2020 may decrease by 5% from 2000 levels (a decrease of 10% compared to the case that assumes no new technology). This is a significant contribution to emission reduction. According to this model, a further emission reduction by 10% in 2020 is possible but costly as it requires emission reduction incentives of up to 10,000 yen per ton CO2 (approximately 100 US/ton). The use of biomass feed-stocks, waste recycling, energy recovery from waste and gas-based co-generation are the main strategies for achieving this emission reduction.

Japanese Carbon Storage in Materials

In order to examine the risk to resource security in Japan, this paper quantifies the outflow of base metals (iron, aluminum, copper, lead, and zinc) through export of end-of-life vehicles (ELVs) from Japan from 1988 to 2005 using the Trade Statistics of Japan and vehicles composition data. Estimates were also made for engine-related rare metals (manganese, nickel, chromium, and molybdenum), under statistical restrictions. This analysis shows that 24% of iron, 38% of aluminum, 13% of copper, 53% of lead, 11% of zinc, and 38% of rare metals in ELVs in Japan were not recycled and flowed out of the country, mostly in the form of used vehicle and parts. The destinations of these metals were mainly developing countries with rudimentary recycling technology. These results strongly indicate that many metal resources that could be utilized domestically from automobiles in Japan were instead scattered and lost overseas. [doi:10.2320/matertrans.MAW200712]

Global Flow of Metal Resources in the Used Automobile Trade

Abstract The NEAT model (Nonenergy-use Emission Accounting Tables) has been developed in order to estimate CO2 emissions caused by so-called nonenergy use of fossil fuels. The model is based on material flow accounting. The model has been applied to a number of countries in order to validate and improve its use. This paper discusses the case study for Japan. The NEAT analysis suggests that emissions in 1996 were 23 Mt higher than previously estimated based on the guidelines of the Intergovernmental Panel on Climate Change (IPCC). This quantity equals 1.9% of the total Japanese greenhouse gas emission. It is recommended to adjust the Japanese emission accounting practice and to apply more detailed emission estimation methods in future years. Given similar results for other countries it is also recommended to improve the IPCC guidelines.

Evaluation of the Possibility of Reducing CO2 Emission from Residential Buildings in Cold Districts of Japan by Employing an Micro Gas Turbine Co-Generation System

This paper examines the traceability of resource movement across borders by quantifying the global flow of base metals (Fe, Al, Cu, Pb, and Zn) through the used passenger car trade in 2005 using trade statistics and vehicle composition data. An estimation method was developed to deal with the often problematic issues associated with trade statistics. This estimation shows that 3.4×106 metric tons of Fe, 3.1×105 metric tons of Al, 7.5×104 metric tons of Cu, 3.2×104 metric tons of Pb, and 2.7×104 metric tons of Zn in used passenger cars globally were not recycled in the country of origin, but rather moved in a global flow out of the country of manufacture. The destinations of these metals were mainly developing countries with rudimentary recycling technology. These results strongly indicate that in developed countries, many metal resources from automobiles that could have been utilized domestically were instead scattered and lost overseas.

Outflow of Resources from Japan focusing on End-of-life Vehicles

Introducing a co-generation system is an effective choice for reducing energy derived CO2 emissions and operating costs for the residential and commercial sectors. In this paper, the possibilities of CO2 emission and operating cost reductions were investigated for the case of a micro gas turbine co-generation system being introduced into a 33 household apartment building located in Sapporo, one of the coldest districts in Japan, which demands a lot of energy in winter for hot-water supply and heating.The results were compared with that of the existing system which is composed of an electricity grid and hot water boilers. The CO2 emissions and operating costs of the co-generation system varied according to the ratio of electricity supply from the grid and MGT, MGT generation efficiencies and the season of the year. Using an MGT with an electricity generation efficiency of 35%, a reduction of 10% (23.4 tonne-CO2/y) of CO2 emissions and 9.4% (433ky) of operating costs could be attained compared with the existing system. In the case of a generation efficiency of 30%, a reduction of 3.4 tonne-CO2/y is expected at the same level of operating cost as the existing system. But in the case of a generation efficiency of 25%, there was no signifi-cant reduction in CO2 emission.