Construction and Commissioning of a Continuous Reactor for Hydrothermal Liquefaction

Hydrothermal liquefaction has proven itself as a promising pathway to the valorisation of low-value wet food residues. The chemistry is complex and many questions remain about the underlying mechanism of the transformation. Little is known about the heat of reaction, or even the thermal effects, of the hydrothermal liquefaction of real biomass and its constituents. This paper explores different methods to evaluate the heat released during the liquefaction of blackcurrant pomace and brewers’ spent grains. Some model compounds have also been evaluated, such as lignin, cellulose and glutamic acid. Exothermic behaviour was observed for blackcurrant pomace and brewers’ spent grains. Results obtained in a continuous reactor are similar to those obtained in a batch reactor. The heat release has been estimated between 1 MJ/kg and 3 MJ/kg for blackcurrant pomace and brewers’ spent grains, respectively. Liquefaction of cellulose and glucose also exhibit exothermic behaviour, while the transformation of lignin and glutamic acid present a slightly endothermic behaviour.

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Renewable Diesel Blendstocks and Biopriviliged Chemicals Distilled from Algal Biocrude Oil Converted via Hydrothermal Liquefaction

10.26434/chemrxiv.9630695 ◽

2019 ◽

Author(s):

Wan-Ting (Grace) Chen ◽

Zhenwei Wu ◽

Buchun Si ◽

Yuanhui Zhang

Keyword(s):

Oxidation Stability ◽

Ash Content ◽

Hydrothermal Liquefaction ◽

Fractional Distillation ◽

Chemical Compositions ◽

Steam Temperature ◽

Renewable Diesel ◽

Commodity Chemicals ◽

Biocrude Oil ◽

Specification Analysis

This study aims to produce renewable diesel and biopriviliged chemicals from microalgae that can thrive in wastewater environment. <i>Spirulina</i> (SP) was converted into biocrude oil at 300ºC for a 30-minute reaction time via hydrothermal liquefaction (HTL). Next, fractional distillation was used to separate SP-derived biocrude oil into different distillates. It was found that 62% of the viscous SP-derived biocrude oil can be separated into liquids at about 270ºC (steam temperature of the distillation). Physicochemical characterizations, including density, viscosity, acidity, elemental compositions, higher heating values and chemical compositions, were carried out with the distillates separated from SP-derived biocrude oil. These analyses showed that 15% distillates could be used as renewable diesel because they have similar heating values (43-46 MJ/kg) and carbon numbers (ranging from C8 to C18) to petroleum diesel. The Van Krevelan diagram of the distillates suggests that deoxygenation was effectively achieved by fractional distillation. In addition, GC-MS analysis indicates that some distillates contain biopriviliged chemicals like aromatics, phenols and fatty nitriles that can be used as commodity chemicals. An algal biorefinery roadmap was proposed based on the analyses of different distillates from the SP-derived biocrude oil. Finally, the fuel specification analysis was conducted with the drop-in renewable diesel, which was prepared with 10 vol.% (HTL10) distillates and 90 vol.% petroleum diesel. According to the fuel specification analysis, HTL10 exhibited a qualified lubricity (<520 µm), acidity (<0.3 mg KOH/g) and oxidation stability (>6 hr), as well as a comparable net heat of combustion (1% lower), ash content (29% lower) and viscosity (17% lower) to those of petroleum diesel. Ultimately, it is expected that this study can provide insights for potential application of algal biocrude oil converted via HTL.

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Closing The Loop For Bio-Oil Production From Microalgae By Hydrothermal Liquefaction

10.31988/scitrends.14642 ◽

2018 ◽

Author(s):

Wenguang Zhou

Keyword(s):

Oil Production ◽

Hydrothermal Liquefaction ◽

Bio Oil ◽

Closing The Loop

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Biotreatability test of bleach wastewaters from pulp and paper mills

Water Science & Technology ◽

10.2166/wst.1997.0492 ◽

1997 ◽

Vol 35 (2-3) ◽

pp. 101-108

Author(s):

X. Wang ◽

T. H. Mize ◽

F. M. Saunders ◽

S. A. Baker

Keyword(s):

Wastewater Treatment ◽

Pulp And Paper ◽

Reductive Dehalogenation ◽

Continuous Reactor ◽

Batch Reactors ◽

Aerobic Treatment ◽

Pulp And Paper Mills ◽

Paper Mills ◽

Degradation Rates ◽

Adsorbable Organic Halide

Research is focused on an integrated way to simultaneously optimize the bleaching operations and subsequent wastewater treatment for pulp and paper mills. Bleach wastewaters from ClO2-bleached pulping studies at Institute of Paper Science and Technology (IPST) were used as the feed for batch reactors to test and rank the treatability and kinetics. The key aspect of the system is the use of sequential anaerobic/aerobic phases to enhance reductive dehalogenation of chloro-organic materials. Two continuous reactor systems, one operated in an anaerobic-aerobic mode and a second in an aerobic-aerobic mode, received bleaching wastewater obtained from a full-scale plant. Acclimated cultures from both continuous reactors were used to quantify the AOX (Adsorbable Organic Halide) and COD removal from various bleaching wastewaters. In general, the sequential anaerobic/aerobic treatment of bleach wastewater can improve both biotreatability and degradation rates.

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Analysis of the precipitation reactor-separation equipment system. Continuous reactor and the rotary vacuum filter operating at the selected negative pressure drop

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19812364 ◽

1981 ◽

Vol 46 (10) ◽

pp. 2364-2370 ◽

Cited By ~ 1

Author(s):

Otakar Söhnel

Keyword(s):

Pressure Drop ◽

Negative Pressure ◽

Continuous Reactor ◽

Vacuum Filter ◽

Continuous Precipitation ◽

Derived Relations ◽

Filtration Area ◽

Separation Equipment ◽

Unit Output ◽

Rotary Vacuum

An analysis has been performed of the continuous precipitation reactor - rotary vacuum filter system (operating at the selected negative pressure drop) on the basis of the unit output. Filtration area necessary for separation of the product from the precipitation reactor is a function of the mean residence time of suspension in the reactor, concentration of the precipitating solutions, porosity of the filtration cake and the filtration negative pressure drop. Application of the derived relations is demonstrated on the continuous precipitation of Mg(OH)2.

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Control of an adiabatic continuous reactor by feeding catalyst

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19802903 ◽

1980 ◽

Vol 45 (11) ◽

pp. 2903-2918 ◽

Cited By ~ 1

Author(s):

Josef Horák ◽

Zina Valášková ◽

František Jiráček

Keyword(s):

Steady State ◽

Reaction Temperature ◽

Continuous Reactor ◽

Control Element ◽

Inlet Temperature ◽

Switching Cycle ◽

Point Temperature ◽

Set Point ◽

Constant Rate ◽

Laboratory Reactor

Algorithms have been presented, analyzed and experimentally tested to stabilize the reaction temperature at constant inlet temperature and composition of the feed by controlled dispensing of the catalyst. The information for the control element is the course of the reaction temperature. If the temperature of the reaction mixture is below the set point, the catalyst is being fed into the reactor at a constant rate. If the reaction temperature is higher the catalyst dispenser is blocked; dispensing of the catalyst is not resumed until the set point temperature has been reached again. The amount of catalyst added is a function of the duration of the switching cycle. The effect has been discussed of the form of this function on the course of the switching cycle. The results have been tested experimentally on a laboratory reactor controlled in an unstable steady state.

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