Renewable Hydrogen Production from Bio-oil in an Aerosol Pyrolysis System

AbstractAbundant bio-oil resulting from thermochemical conversion of biomass could potentially be an important source of renewable hydrogen (H2). Direct pyrolysis of hardwood bio-oil was carried out in an aerosol reaction system to evaluate temperature and catalytic effects on H2 production. The laboratory system achieved stable H2 output for hours without the need of steam or catalyst rejuvenation. Hydrogen yields (∼50%) are comparable to those from fixed-bed reactors under typical pyrolysis temperatures (700 – 900°C). Pure nickel catalyst enhanced hydrogen yield at lower temperatures (≤ 800°C) but suppressed it at higher temperatures, while an activated charcoal catalyst showed activities only above 800°C. Elemental balance calculations estimate an overall enthalpy of reaction of 2 – 3kJ/g bio-oil, less than 17% of the bio-oil heating value and lower than that of conventional steam-reforming processes. Advantages and future research needs of the aerosol approach for bio-oil/hydrogen conversion are discussed

Multi-Wavelength Light Absorption of Black and Brown Carbon at a High-Altitude Site on the Southeastern Margin of the Tibetan Plateau, China

The Tibetan Plateau (TP) is one of the world\u27s most sensitive areas for climate change, but the lack of information on light-absorption by aerosols limits the understanding of climate forcing feedbacks. Here, the contributions of black carbon (BC) and brown carbon (BrC) to light absorption and radiative forcing were investigated. Absorption Ångström exponents (α), mass absorption cross sections (MAC), and absorption coefficients (babs) for selected wavelengths were measured for a year of aerosol samples collected at Lulang on the southeast TP. Aerosol absorption at all wavelengths was strongest in the pre-monsoon when levoglucosan, a biomass burning indicator, was elevated. The contributions of BC, BrC, and dust to babs were decoupled. Results showed that dust contributed 8.5% to the total light absorption at 405 nm and 3.9% 808 nm. A two-component model indicated that BC and BrC contributed 48.7% and 44.0% to total babs at 405 nm but BrC had a smaller effect at middle-visible wavelengths. Elevated babs,non-dust,BC and babs,non-dust,BrC and a high αBrC but low αaerosol values in the pre-monsoon were attributed to biomass burning, which produces not only BrC but also BC which has a much lower α value. Average non-dust MACs for BC and BrC at 405 nm were 6.1 ± 2.8 and 0.72 ± 0.55 m2 g−1, respectively. Nonparametric statistical tests showed that the MACnon-dust,BC was relatively constant but MACnon-dust, BrC was more variable. In addition, BrC was correlated with non-dust babs,BC and MACnon-dust,BC in winter and the pre-monsoon, implying BrC and BC shared sources in those two seasons, but lower correlations in the monsoon and post-monsoon suggest that a mixture of sources impacted BrC (e.g., biogenic emission, secondary formation, etc.). Finally, the relative contributions of BrC to BC for radiative forcing from 405 to 808 nm were 29.4 ± 9.5% with no remarkable seasonal differences, confirming the importance of BrC to light absorption in the near UV throughout the year. As a result, the BrC absorption is an important additional factor which needs to be considered in atmospheric models, although the atmospheric heating by BC seems to be a larger climate forcer in this region

A Biomass Combustion Chamber: Design, Evaluation, and a Case Study of WheatStraw Combustion Emission Tests

Open biomass burning is a significant source of trace gases and particulate pollutants on a global scale and plays an important role in both atmospheric chemistry and climate change. To study the emission characteristics of biomass burning, with a focus on crop residue combustion in Northwest China, a combustion chamber was established. This paper describes the design, structure, and operating principles of the chamber. A series of evaluation tests were conducted, demonstrating its applicability in emission studies. The combustion chamber was equipped with a thermoanemometer and a dilution sampler as well as multiple sampling ports for interfacing with different monitors. A case study of wheat straw combustion was performed to demonstrate reproducibility and comparability of the derived emission factors with prior studies. The combustion chamber may be applied to develop emission factors to update emission inventories and source profiles for improving source apportionment.</p

DUNE Offline Computing Conceptual Design Report

International audienceThis document describes Offline Software and Computing for the Deep Underground Neutrino Experiment (DUNE) experiment, in particular, the conceptual design of the offline computing needed to accomplish its physics goals. Our emphasis in this document is the development of the computing infrastructure needed to acquire, catalog, reconstruct, simulate and analyze the data from the DUNE experiment and its prototypes. In this effort, we concentrate on developing the tools and systems thatfacilitate the development and deployment of advanced algorithms. Rather than prescribing particular algorithms, our goal is to provide resources that are flexible and accessible enough to support creative software solutions as HEP computing evolves and to provide computing that achieves the physics goals of the DUNE experiment

DUNE Offline Computing Conceptual Design Report

This document describes Offline Software and Computing for the Deep Underground Neutrino Experiment (DUNE) experiment, in particular, the conceptual design of the offline computing needed to accomplish its physics goals. Our emphasis in this document is the development of the computing infrastructure needed to acquire, catalog, reconstruct, simulate and analyze the data from the DUNE experiment and its prototypes. In this effort, we concentrate on developing the tools and systems thatfacilitate the development and deployment of advanced algorithms. Rather than prescribing particular algorithms, our goal is to provide resources that are flexible and accessible enough to support creative software solutions as HEP computing evolves and to provide computing that achieves the physics goals of the DUNE experiment

DUNE Offline Computing Conceptual Design Report

This document describes Offline Software and Computing for the Deep Underground Neutrino Experiment (DUNE) experiment, in particular, the conceptual design of the offline computing needed to accomplish its physics goals. Our emphasis in this document is the development of the computing infrastructure needed to acquire, catalog, reconstruct, simulate and analyze the data from the DUNE experiment and its prototypes. In this effort, we concentrate on developing the tools and systems thatfacilitate the development and deployment of advanced algorithms. Rather than prescribing particular algorithms, our goal is to provide resources that are flexible and accessible enough to support creative software solutions as HEP computing evolves and to provide computing that achieves the physics goals of the DUNE experiment

DUNE Offline Computing Conceptual Design Report

This document describes Offline Software and Computing for the Deep Underground Neutrino Experiment (DUNE) experiment, in particular, the conceptual design of the offline computing needed to accomplish its physics goals. Our emphasis in this document is the development of the computing infrastructure needed to acquire, catalog, reconstruct, simulate and analyze the data from the DUNE experiment and its prototypes. In this effort, we concentrate on developing the tools and systems thatfacilitate the development and deployment of advanced algorithms. Rather than prescribing particular algorithms, our goal is to provide resources that are flexible and accessible enough to support creative software solutions as HEP computing evolves and to provide computing that achieves the physics goals of the DUNE experiment

DUNE Offline Computing Conceptual Design Report

This document describes Offline Software and Computing for the Deep Underground Neutrino Experiment (DUNE) experiment, in particular, the conceptual design of the offline computing needed to accomplish its physics goals. Our emphasis in this document is the development of the computing infrastructure needed to acquire, catalog, reconstruct, simulate and analyze the data from the DUNE experiment and its prototypes. In this effort, we concentrate on developing the tools and systems thatfacilitate the development and deployment of advanced algorithms. Rather than prescribing particular algorithms, our goal is to provide resources that are flexible and accessible enough to support creative software solutions as HEP computing evolves and to provide computing that achieves the physics goals of the DUNE experiment