Energy Self-Sufficiency Conditions of Ethanol Autothermal Reforming: a Simulation Study

Abstract Natural gas steam reforming is commonly used for hydrogen production. However, research has shown that ethanol autothermal reforming can produce cleaner hydrogen gas efficiently. Despite this, there is a lack of studies on the energy self-sufficiency conditions of the ethanol autothermal reform. In this paper, we use simulations and the Response Surface Methodology (RSM) for the multivariate analysis of the energy self-sufficiency conditions in this process. First, we constructed and validated an industrial flowchart. After that, RSM allowed us to assess the process variables effects. The process variables studied were temperature (0 to 1000 ºC), pressure (20 to 30 bar), steam/ethanol ratio (2 to 5 mol/mol) and O2/ethanol ratio (0 to 1.5 mol/mol). We observe that the temperature and steam/ethanol ratio increase have a positive effect on hydrogen production. On the contrary, the O2/ethanol ratio increase has a negative effect, and the pressure increase is not statistically significant on hydrogen production. Therefore, the pressure was used at its minimum level (20 bar) while the temperature and the steam/ethanol ratio at its maximum levels (1000 ºC and 5 mol/mol). We also evaluated the energy consumption for the Autothermal Reactor (ATR). The reactor consumed 477.92 kJ/mol ethanol to produce 5.12 mol H2/mol ethanol when we use 1000 ºC, 20 bar, steam/ethanol 5 mol/mol, and O2/ethanol 0 mol/mol. ATR's energy self-sufficiency is achieved by using 1000 ºC, 20 bar, steam/ethanol 5 mol/mol, and O2/ethanol 0.86 mol/mol. In these conditions, 3.95 mol H2/mol ethanol is produced with 0 kJ/mol ethanol.

Hydrogen agronomy: research progress and prospects / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Agriculture is the foundation of social development. Under the pressure of population growth, natural disasters, environmental pollution, climate change, and food safety, the interdisciplinary "new agriculture" is becoming an important trend of modern agriculture. In fact, new agriculture is not only the foundation of great health and new energy sources, but is also the cornerstone of national food security, energy security, and biosafety. Hydrogen agronomy focuses mainly on the mechanism of hydrogen gas (H

Hydrogen agronomy: research progress and prospects / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Agriculture is the foundation of social development. Under the pressure of population growth, natural disasters, environmental pollution, climate change, and food safety, the interdisciplinary “new agriculture” is becoming an important trend of modern agriculture. In fact, new agriculture is not only the foundation of great health and new energy sources, but is also the cornerstone of national food security, energy security, and biosafety. Hydrogen agronomy focuses mainly on the mechanism of hydrogen gas (H2) biology effects in agriculture, and provides a theoretical foundation for the practice of hydrogen agriculture, a component of the new agriculture. Previous research on the biological effects of H2 focused chiefly on medicine. The mechanism of selective antioxidant is the main theoretical basis of hydrogen medicine. Subsequent experiments have demonstrated that H2 can regulate the growth and development of plant crops, edible fungus, and livestock, and enhance the tolerance of these agriculturally important organisms against abiotic and biotic stresses. Even more importantly, H2 can regulate the growth and development of crops by changing the soil microbial community composition and structure. Use of H2 can also improve the nutritional value and postharvest quality of agricultural products. Researchers have also shown that the biological functions of molecular hydrogen are mediated by modulating reactive oxygen species (ROS), nitric oxide (NO), and carbon monoxide (CO) signaling cascades in plants and microbes. This review summarizes and clarifies the history of hydrogen agronomy and describes recent progress in the field. We also argue that emerging hydrogen agriculture will be an important direction in the new agriculture. Further, we discuss several scientific problems in hydrogen agronomy, and suggest that the future of hydrogen agronomy depends on contributions by multiple disciplines. Important future research directions of hydrogen agronomy include hydrogen agriculture in special environments, such as islands, reefs, aircraft, and outer space.

Design of a microbial fuel cell and its transition to microbial electrolytic cell for hydrogen production by electrohydrogenesis.

Anaerobic bacteria were isolated from industrial wastewater and soil samples and tested for exoelectrogenic activity by current production in double chambered microbial fuel cell (MFC), which was further transitioned into a single chambered microbial electrolytic cell to test hydrogen production by electrohydrogenesis. Of all the cultures, the isolate from industrial water sample showed the maximum values for current = 0.161 mA, current density = 108.57 mA/m2 and power density = 48.85 mW/m2 with graphite electrode. Maximum voltage across the cell, however, was reported by the isolate from sewage water sample (506 mv) with copper as electrode. Tap water with KMnO4 was the best cathodic electrolyte as the highest values for all the measured MFC parameters were reported with it. Once the exoelectrogenic activity of the isolates was confirmed by current production, these were tested for hydrogen production in a single chambered microbial electrolytic cell (MEC) modified from the MFC. Hydrogen production was reported positive from co-culture of isolates of both the water samples and co-culture of one soil and one water sample. The maximum rate and yield of hydrogen production was 0.18 m3H2/m3/d and 3.2 mol H2/mol glucose respectively with total hydrogen production of 42.4 mL and energy recovery of 57.4%. Cumulative hydrogen production for a five day cycle of MEC operation was 0.16 m3H2/m3/d.

Effect of Acupuncture Stimulation on the Blood Flow of the Skeletal Muscles in Rabbits / 全日本鍼灸学会雑誌

To clarify the effect of acupuncture on the skeletal muscle blood flow, measurements of muscle blood flow by hydrogen gas clealance method were taken on the left anterior tibial muscles of thirty rabbits (weighing about 2.5 to 3.3 kg) anesthetized with pentobarbital sodium (35mg/kg, i.v.). Arterial blood pressure in the common carotid artery and body temperature were also measured.<BR>Blood flow was measured 6 times every 10 min. In the stimulation group, acupuncture needles were inserted into the center of the anterior tibial muscle before the third measurement and “sparrow pecking” was performed, then the needles were removed. In the denervation group, the sciatic nerve was cut to observe the influence of denervation on the effect of acupuncture.<BR>In the stimulation group (n=12), a significant increase in blood flow to the muscles occurred after acupuncture stimulation, compared with the control group (n=12). The increase in blood flow in the stimulation group was maintained until the final measurement. Arterial blood pressure and body temperature did not change.<BR>The blood flow values in the second and third measurements were 18.1 ± 2.2, and 17.6 ± 2.4, respectively, in the control group, and 17.8 ± 1.8 and 25.9 ± 2.2 ml/min/ 100g (mean ± S.E.) in the stimulation group. The changes in blood flow values from the second to the third measurement were -0.5 ± 0.3 ml/min/100g in the control group, and +8.2 ± 2.0 ml/min/100g in the stimulation group. An increase in blood flow after acupuncture stimulation also occurred in the denervation group (n=3).<BR>Despite there being no change in arterial blood pressure. blood flow was increased after acupuncture stimulation, and the increment of blood flow after acupuncture stimulus was also observed in the denervation group. Therefore, the increment of blood flow seems to have been caused by vasodilation of the blood vessels induced by axon reflex.