The American Diabetes Association (ADA) "Standards of Care in Diabetes" includes the ADA's current clinical practice recommendations and is intended to provide the components of diabetes care, ...general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee, a multidisciplinary expert committee, are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA's clinical practice recommendations and a full list of Professional Practice Committee members, please refer to Introduction and Methodology. Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC.
Syngas from gasification of carbonaceous feedstocks is used for power production and synthesis of fuels and commodity chemicals. Impurities in gasification feedstocks, especially sulfur, nitrogen, ...chlorine, and ash, often find their way into syngas and can interfere with downstream applications. Incomplete gasification can also produce undesirable products in the raw syngas in the form of tar and particulate char. This paper reviews the technologies for removing contaminants from raw syngas. These technologies are classified according to the gas temperature exiting the cleanup device: hot (T > 300 °C), cold (T < ∼100 °C), and warm gas cleaning regimes. Cold gas cleanup uses relatively mature techniques that are highly effective although they often generate waste water streams and may suffer from energy inefficiencies. The majority of these techniques are based on using wet scrubbers. Hot gas cleaning technologies are attractive because they avoid cooling and reheating the gas stream. Many of these are still under development given the technical difficulties caused by extreme environments. Warm gas cleaning technologies include traditional particulate removal devices along with new approaches for removing tar and chlorine.
► A comprehensive review of cleaning methods for syngas is presented. ► The source of each contaminant group and issues they cause are discussed. ► Contaminants include: particulate matter, tar, sulfur, nitrogen, alkali, chlorine. ► Cleaning processes include hot, cold, and intermediate temperature methods.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
As the field of fast pyrolysis has matured, it has been accompanied by a kind of orthodoxy in its practice. Among these orthodoxies are the following: (1) oxygen should be excluded from the pyrolysis ...process; (2) little sugar is produced during pyrolysis; and (3) the major product of pyrolysis is a low-value emulsion in water. Adherence to these tenets is an impediment to the commercial development of fast pyrolysis. Over the past 15 years, research at Iowa State University’s Bioeconomy Institute has challenged these tenets with what might be called heterodoxy in the science and engineering of fast pyrolysis: adding oxygen, producing sugars, and fractionating bio-oil into valorized products. This paper reviews these new approaches to pyrolysis and concludes with an outlook for further developing them.
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IJS, KILJ, NUK, PNG, UL, UM
We report an economically- and environmentally-promising microalgae biorefinery pathway, which uses catalytic pyrolysis with HZSM-5 catalyst to convert whole microalgae into aromatic hydrocarbons. ...This process produces valuable petrochemicals and ammonia, the latter of which can be recycled as a fertilizer for microalgae cultivation. We tested samples of lipid-lean green microalgae,
Chlorella vulgaris
, at various reaction temperatures and catalyst loads. We also tested samples of lignocellulosic biomass, red oak, for comparison. Our results demonstrated that catalytic pyrolysis of microalgae produces better aromatic yields and better aromatic distributions than catalytic pyrolysis of red oak. The maximum carbon yield of aromatics from microalgae was 24%, while that from red oak was 16.7%. Moreover, catalytic pyrolysis of microalgae produced more monocyclic aromatics than were produced by catalytic pyrolysis of lignocellulosic biomass. Microalgae present many advantages as a feedstock for biofuel. With the promise catalytic pyrolysis offers for solving some of microalgae's disadvantages, microalgae biorefineries move one step closer to economic and environmental feasibility.
Catalytic pyrolysis of microalgae converts protein-rich microalgae into green aromatics, while nitrogen in protein is released in ammonia and recycled for algae growth.
The American Diabetes Association (ADA) "Standards of Care in Diabetes" includes the ADA's current clinical practice recommendations and is intended to provide the components of diabetes care, ...general treatment goals and guidelines, and tools to evaluate quality of care. Members of the ADA Professional Practice Committee, a multidisciplinary expert committee, are responsible for updating the Standards of Care annually, or more frequently as warranted. For a detailed description of ADA standards, statements, and reports, as well as the evidence-grading system for ADA's clinical practice recommendations and a full list of Professional Practice Committee members, please refer to Introduction and Methodology. Readers who wish to comment on the Standards of Care are invited to do so at professional.diabetes.org/SOC.
•A mixture of red oak and HDPE is fast pyrolyzed in a fluidized bed.•Optimum pyrolysis temperature was 625°C.•A significant synergistic effect between red oak and HDPE was found.•Co-pyrolysis reduces ...char formation from red oak.•Pyrolysis char had a lower BET surface area than red oak biochar.
Co-pyrolysis of red oak and high density polyethylene (HDPE) was conducted in a laboratory-scale, continuous fluidized bed reactor in a temperature range from 525 to 675°C. Pyrolysis products, including two fractions of pyrolysis-oil, non-condensable gases and char were analyzed to assess the influence of pyrolysis temperature and co-feeding of biomass with HDPE. It was found that increasing pyrolysis temperature up to 625°C promoted the production of pyrolysis-oil and its yield reached 57.6wt%. Further increase in pyrolysis temperature caused the cracking of pyrolysis-oil to form light gases rich in hydrocarbons. Organic phase of pyrolysis-oil produced from plastic-biomass mixture (PBM) had a higher heating value (HHV) up to 36.6MJ/kg contributed by the additive effect of HDPE-derived aliphatic hydrocarbons. A significant synergetic effect was also observed during co-pyrolysis. Co-pyrolysis with HDPE increased the production of furan, acids and water from red oak. Co-presence of HDPE also inhibited char formation from red oak and improved the HHV of the resulting char. The char produced from co-pyrolysis had a significantly lower BET surface area than red oak biochar. Not only did HDPE-derived particulate matter blocks the pores, the synergetic interaction also resulted in the formation of large and shallow micro-pores on the char surface.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
•The aqueous phase of bio-oil showed inhibition in anaerobic digestion.•The inhibition was decreased by overliming pretreatment.•Directed evolution enhanced the tolerance of microbial community to ...the toxicity.•Combination of pretreatment and directed evolution showed improved methane yield.•The archaeal community shifted from acetoclastic to hydrogenotrophic methanogenesis.
Among the products of pyrolysis is an aqueous phase (AP), which contains a significant fraction of carbon but is too dilute to make recovery of this organic content cost-effectively. This study was to explore the use of AP for anaerobic digestion. Different treatment methods including overliming, Fenton's reagent oxidation, bleaching and activated carbon adsorption were investigated to reduce toxicity of AP. Overliming treatment increased biogas production up to 32-fold compared to non-treated AP. Enhancing the tolerance of the bacterial and archaeal community to the AP toxicity was also attempted with a directed evolution method, resulting the microbes’ tolerance to AP from 5% to 14%. Directed evolution resulted a major bacterial taxa as Cloacimonetes, Firmicutes, and Chloroflexi, while shifted the predominant archaea shifted from acetoclastic to hydrogenotrophic methanogens. Collectively, the results demonstrated that combining feedstock treatment and directed evolution of the microbial community is an effective way for AP anaerobic digestion.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
We report on the catalytic pyrolysis of switchgrass and its three main components (cellulose, hemicellulose and lignin) over H-ZSM5 catalyst. The yields of aromatic hydrocarbons for the three ...components decreased in the following order: cellulose > hemicellulose >> lignin. Moderately higher temperature favored formation of aromatics. The results indicate that H-ZSM5 catalyst did not remove oxygen in an optimal pathway for catalytic pyrolysis of biomass. Dehydration was the dominant oxygen removal mechanism for catalytic pyrolysis, while decarbonylation to CO was favored over decarboxylation to CO sub(2). This suggests that higher yields of aromatics might be achieved by catalyst improvements or reactor design that optimizes deoxygenation pathway. For cellulose and hemicellulose, coke produced catalytically contributed a larger fraction of solid carbonaceous residue than char from purely thermal processes. In the case of lignin, thermal rather than catalytic processes primarily contribute to the production of solid carbonaceous residue. Product distribution from catalytic pyrolysis of switchgrass appeared to be the additive contribution of the three individual components, which indicates that there was no significant interaction among the biomass-derived products.
In this study, we compared ex-situ catalytic pyrolysis (CP) and in-situ CP of hybrid poplar in a micro-reactor system. When both pyrolysis and catalysis were performed at 700 °C, the carbon yield of ...olefins was greater for ex-situ CP than for in-situ CP (17.4% vs. 5.4%). On the other hand, in-situ CP produced more aromatic hydrocarbons than ex-situ CP (26.1% vs. 18.9%). The remarkably high yield of olefins from ex-situ CP indicates the potential of exploiting the process to preferentially produce olefins as a primary product from biomass, with aromatics being the secondary products. The carbon yield of carbonaceous residues from ex-situ CP was 18.6% compared to 31.3% for in-situ CP. Substantial carbon was deposited as char during ex-situ CP, which could be easily recovered as by-product, simplifying catalyst regeneration. The effects of catalyst loading, pyrolysis temperature and catalysis temperature on product distributions for ex-situ CP were also investigated. Our results showed that catalyst temperature strongly affected product distribution. While high catalyst temperature enhanced both olefin and aromatic production, yield of olefin increased to a greater extent than did aromatics. Neither pyrolysis temperature nor catalyst loadings had significant effect on product distribution for ex-situ CP.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
► Lipid-extracted microalgae remnants were pyrolyzed in a fluidized bed reactor. ► Bio-oil yield of 53% was achieved while biochar and gas yield were 31% and 10%. ► Ninety-four percent of the energy ...content ofalgal biomass was recovered in bio-oil and biochar.
In this study, pyrolysis of microalgal remnants was investigated for recovery of energy and nutrients. Chlorella vulgaris biomass was first solvent-extracted for lipid recovery then the remnants were used as the feedstock for fast pyrolysis experiments using a fluidized bed reactor at 500°C. Yields of bio-oil, biochar, and gas were 53, 31, and 10wt.%, respectively. Bio-oil from C. vulgaris remnants was a complex mixture of aromatics and straight-chain hydrocarbons, amides, amines, carboxylic acids, phenols, and other compounds with molecular weights ranging from 70 to 1200Da. Structure and surface topography of the biochar were analyzed. The high inorganic content (potassium, phosphorous, and nitrogen) of the biochar suggests it may be suitable to provide nutrients for crop production. The bio-oil and biochar represented 57% and 36% of the energy content of the microalgae remnant feedstock, respectively.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
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