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The utilization of biomass can not only alleviate the energy crisis but also reduce the pollution of fossil fuels to the environment. Biomass gasification is one of the main utilization methods, which can effectively convert biomass into high-value and wide-use gasification gas. However, this process inevitably produces the by-product tar, which affects the yield of syngas. In order to solve this problem, a two-stage process combining biomass pyrolysis and CO2 catalytic reforming is proposed in this paper, which is used to prepare high calorific value syngas rich in H2 and CO and reduce the by-product tar of biomass gasification while realizing the resource utilization of CO2. The effects of the reforming temperature and CO2/C ratio on the gas yield and calorific value of biomass were investigated by catalytic gasification reforming device, and the system energy consumption was analyzed. With the increase of reforming temperature, the yield of CO increased, and the yield of H2 and the calorific value of gas increased first and then decreased. Increasing the CO2/C ratio within a proper range is beneficial to the formation of syngas. When the reforming temperature is 900 °C and the CO2/C ratio is 1, syngas with a high gas calorific value is obtained, which of is 2.75 MJ/kg is obtained. At this time, the yield of H2 and CO reached the maximums, which were 0.46 Nm3/kg and 0.28 Nm3/kg, respectively. Under these conditions, the total energy consumption of the system is 0.68 MJ/kg, slightly more than 0, and does not require too much external heat. [ABSTRACT FROM AUTHOR]

In this article, the bifunctional NiO/CaO@C12A7 catalysts having reforming catalytic effect and CO2 adsorption effect were prepared with co‐precipitation method, and were used in the sorption‐enhanced steam reforming process of tar from RCOG for hydrogen production. Among six kinds of samples with different load ratios, the catalyst with the CaO:C12A7:NiO ratio of 70:15:15 showed the best catalytic performance for the steam reforming of tar to produce H2 as well as the excellent characterization. Under the action of this catalyst, the H2 yield obtained from the steam reforming process of 1‐methylnaphthalene (C11H10) as the tar model compound were higher than that from the common steam reforming process, and the best H2 yield was obtained at the reforming temperature of 750°C, the S/C ratio of 12 and the WHSV of 0.055 hr−1, with the value of 83.9%. [ABSTRACT FROM AUTHOR]

From the thermodynamic analysis of the steam reforming process of raw coke oven gas, the H2 amplification factor after the reforming can reach the highest (over 3.5) in the temperature range between 650 and 800°C, where the bifunctional catalysts to be prepared should have the best CO2 adsorption performances as well as the excellent reforming catalytic performances. In this article, the bifunctional NiO/CaO@C12A7 catalysts were prepared at different preparation parameters, and among them, the catalyst sample prepared at the calcination temperature of 1,000°C and the calcination time of 4 h with co‐precipitation (CP) method showed the best CO2 adsorption capacity as well as the best characterizations. And, in the steam reforming experiments of tar component from RCOG (Raw coke oven gas), under the effect of the bifunctional catalyst, the higher H2 yield was obtained than that over the mixture of the independent reforming catalyst and CO2 sorbent. [ABSTRACT FROM AUTHOR]

Four rainwater diversion patterns including undisturbed soil ditch (T1), slope compaction (T2), asbestos sheet covering after compaction (T3) and plastic film covering after compaction (T4) were set in cornfield in arid areas of Yunnan Province, and effects of various patterns on rainwater collection efficiency, water utilization efficiency and corn yield were studied. The results shows that rainwater collection efficiency, water utilization efficiency and corn yield of the four diversion patterns presented the same trend, namely T4 > T3 > T2 > T1. Overall, rainwater collection efficiencies of the four diversion patterns ranged from 41.7% to 58.7%; compared with T1, water utilization efficiencies of T2, T3 and T4 increased by 34.9%, 53.5%> and 92.5%>, and maize yields of them improved by 1 767.0, 1 981. 5 and 2 385.0 kg/hm². [ABSTRACT FROM AUTHOR]