CHEMICAL WEATHERING PROCESSES AND ATMOSPHERIC CO_2 CONSUMPTION OF HUANGHE RIVER AND CHANGJIANG RIVER BASINS

Rock weathering plays an important role in studying the long-term carbon cycles and global climatic change. According to the statistics analysis, the Huanghe (Yellow) River water chemistry was mainly controlled by evaporite and carbonate weathering, which were responsible for over 90% of total dissolved ions. As compared with the Huanghe River basin, dissolved load of the Changjiang (Yangtze) River was mainly originated from the carbonate dissolution. The chemical weathering rates were estimated to be 39.29t/(km(2).a) and 61.58t/(km(2).a) by deducting the HCO3- derived from atmosphere in the Huanghe River and Changjiang River watersheds, respectively. The CO2 consumption rates by rock weathering were calculated to be 120.84 x 10(3)mol/km(2) and 452.46 x 10(3)mol/km(2) annually in the two basins, respectively. The total CO2 consumption of the two basins amounted to 918.51 x 10(9)mol/a, accounting for 3.83% of the world gross. In contrast to other world watersheds, the stronger evaporite reaction and infirm silicate weathering can explain such feature that CO2 consumption rates were lower than a global average, suggesting that the sequential weathering may be go on in the two Chinese drainage basins.

Analysis of CO2 Emissions and the Mechanism of the Industrial Enterprises above Designated Size（IEDS） in Resource-based Cities by Application of Geographical Detector Technology

Resource-based cities are the most important players in responding to climate change and achieving low carbon development in China.An analysis of relevant data(such as the energy consumption)showed an inter-city differentiation of CO2 emissions from energy consumption,and suggested an influence of the Industrial Enterprises above Designated Size(IEDS)in resource-based industrial cities at the prefecture level and above in different regions.Then by geographical detector technology,the sizes of each influencing mechanism on CO2 emissions from energy consumption of the IEDS were probed.This analysis showed that significant spatial differences exist for CO2 emissions from energy consumption and revealed several factors which influence the IEDS in resource-based cities.(1)In terms of unit employment,Eastern and Western resource-based cities are above the overall level of all resource-based cities;and only Coal resource-based cities far exceeded the overall level among all of the cities in the analysis.(2)In terms of unit gross industrial output value,the Eastern,Central and Western resources-based cities are all above the overall level for all the cities.Here also,only Coal resource-based cities far exceeded the overall level of all resources-based cities.Economic scale and energy structure are the main factors influencing CO2 emissions from energy consumption of the IEDS in resource-based cities.The factors influencing CO2 emissions in different regions and types of resource-based cities show significant spatial variations,and the degree of influence that any given factor exerts varies among different regions and types of resource-based cities.Therefore,individualized recommendations should be directed to different regions and types of resource-based cities,so that the strategies and measures of industrial low carbon and transformation should vary greatly according to the specific conditions that exist in each city.

A mass and energy estimation for the hydrogen utilization in the iron-making process

The possibility of using hydrogen to lower CO 2 emissions in the iron-making process was confirmed by the heat and mass balances in the blast furnace operation. The mass and heat balances for hydrogen utilization in the blast furnace were estimated by using the basic concept of RIST operating diagram. In this study, the RIST operating diagram was modified to be suitable for representing the operation with respect to hydrogen, where the RIST operating diagram is a graphical representation of heat and mass balance in blast furnace operation. RIST operating diagram was applied here to some individual parameters of interest such as H 2 injection in blast furnace process to reduce coke (carbon consumption). It was observed that the point W moved to the right in the RIST operating diagram under the condition of increasing hydrogen injection at tuyere, which originates from the contribution of gas composition (O/H 2 ) equilibrated with Fe/FeO at a certain temperature. Point P also moved downward due to heat requirement with respect to hydrogen utilization, by which the new RIST operating diagram for hydrogen utilization was able to be constructed. Under the condition of hydrogen injection, the expected overall carbon consumption in the blast furnace decreased due to the contribution of hydrogen.