Co-pyrolysis is one of the most promising options for using coal and biomass because coal is low in hydrogen and biomass can supplement the hydrogen content to make a more valuable and reactive product gas. The mixture of coal and biomass is prepared, with the mass ratio of biomass varying between 0 and 100%. Due to limitations in experimental methods, the data points measured in these studies are coarse and therefore, insufficient for kinetic energy analysis and model comparison. Therefore, a mathematical model has been proposed to combine a study of the influence of experimental parameters with different materials to understand better the effect of these parameters on pyrolysis with the rigorous control of experimental conditions in terms of precision and repeatability. The advantages of mathematical modelling co-pyrolysis make it possible to design a reaction scheme capable of describing this phenomenon and extracting kinetic parameters, making it possible to compare fuels, which can be used for the simulation of this process in thermal power plants. The experimental analysis of measured co-pyrolysis data was taken from literature work to validate the proposed model. The numerical model results are in good agreement with the experimental data for co-pyrolysis. The most significant degree of synergetic effects on the product yields was observed at 600 degrees C and a biomass blending ratio of 70 wt%. Furthermore, the improvement of char reactivity also identifies the synergies in co-pyrolysis.

This work, led by the SUPERGEN Bioenergy Hub of United Kingdom (UK), examines the current status of the UK bioenergy research, identifies important research gaps and makes recommendations for exploitation of current capabilities and future research development. It was based on a survey-based research covering 71 bioenergy research stakeholders' responses and a taxonomy map with key bioenergy topics and subtopics carefully defined. This novel study adapts the concept of "business intelligence" to innovation, in order to transform data into actionable intelligence that informs about strategic decisions. The map shows that the UK bioenergy research explores the whole bioenergy chain, and the areas with high probability of exploitation and improvement identified are: biomass pre-treatment; application of bioenergy products and standardisation, portfolio of commercialisation opportunities, and research into market opportunities. Working on them will help technology and bio-products to be market-ready. To complement the outcomes of this map, a scientometric review was done through analysing the trend of the number of publication, publication impacts, and stakeholders' co-authorships. The study reveals that pyrolysis had the highest number of publications during 2017, in agreement with the major number of participants; and the highest publication growth was found in both pyrolysis and gasification. Conversely, combustion, which had the lowest number of stakeholders (by 30%), had the highest number of publications until 2015, indicating combustion research is more concentrated in specific stakeholders. Hydrolysis and fermentation showed high number of research stakeholders, but the lowest number of publications suggest that more effort in publication should be done.

This study aims to compare the potential of Virginia mallow to other high yielding perennial grasses and hardwoods by characterising and comparing fast pyrolysis product yields. Feedstocks selected for this study include miscanthus ( Miscanthus x giganteus ), Virginia mallow ( Sida hermaphrodita ), willow short rotation coppice (SRC) ( Salix viminalis ) and oak ( Quercus robur ). The experimental work was split into two sections: analytical (Py–GC–MS) and laboratory-scale processing using a 300 g h −1 continuous bubbling fluidised bed reactor. Pyrolysis–gas chromatography–mass spectrometry (Py–GC–MS) has been used to quantify pyrolysis products from these feedstocks by simulating fast pyrolysis heating rates using a CDS 5200 pyrolyser closed coupled to a PerkinElmer Clarus 680 GC–MS. High bio-oil yields were achieved for Virginia mallow, willow SRC and oak (65.36, 62.55 and 66.43 wt% respectively), but miscanthus only produced a yield of 53.46 wt% due to increased feedstock ash content. The water content in the bio-oil is highest from miscanthus (17.64 wt%) and relatively low in the Virginia mallow and hardwoods willow SRC and oak (12.49, 13.88 and 14.53 wt%). Similar high yields of bio-oil and low yields of char and non-condensable gas compared to willow SRC make Virginia mallow an attractive feedstock for fast pyrolysis processing. Graphic Abstract

Bio-oil production from renewable sources has been seen as suitable alternative to supply future energy demand. Perennials grasses are currently being developed as a suitable second-generation biofuel feedstock. It has advantages such as rapid growth rate, easy to grow, minimal maintenance and utilise marginal land without competing with food supply. Taking into account of the various challenges attributed to the transformation of second-generation biomass for energy production, this work systematically looks at the ecological perspective and the availability for bioenergy production from Imperata Cylindrica in Brunei Darussalam. Biomass characterisation was carried out to determine the properties and energy content, meanwhile py-GC/MS study was conducted to identify building blocks of value-added chemical from L cylindrica. The physicochemical properties of feedstock was thoroughly evaluated using thermogravimetric analysis, proximate analysis, elemental analysis, compositional analysis, calorific value, and analytical pyrolysis interfaced with gas chromatograph (Py-GC/MS). Characterisation results indicate that Imperata Cylindrica has a calorific value of 18.39 MJ/kg, with low ash content and high percentage of volatile matter. Py-GC/MS analysis revealed the presence of furfural, 2,3-dihydrobenzofuran, 4-vinylguaiacol, propenylguaiacol, guaiacol and 4-ethylphenol. The fixed-bed pyrolysis experiment of imperata cylindrica showed that the yield of bio-oil increases with the increase of temperature and it reached a peak of 37.16% at 500 degrees C. These results show that Imperata Cylindrica is suitable as feedstock for bio-oil production via pyrolysis process.

Bio-oil from the fast pyrolysis of agro-residues still needs to contemplate different production scenarios to look for its feasibility. For this reason, in this work the effect of a range of fast pyrolysis temperature (450, 480, 510 and 550 °C) processing rape straw biomass (with high K content) has been studied in a continuous bubbling fluidised bed reactor. It was found that the catalytic effect of the inorganic content was different at each fast pyrolysis temperature, with the lower temperatures resulting in the highest yield of bio-oil due to minor catalytic effect (up to 41.39 wt%). It was also found that at 480 °C the bio-oil presented the best combination of physico-chemical features such as non-separation phase and the lowest water content; yield (39.65 wt%) and HHV (19.23 MJ/kg), containing a high concentration of phenolic compounds. At the fast pyrolysis temperature of 510 °C and 550 °C, the conjunction effect of temperature and the catalytic effect provoked bio-oil separation into two phases and a higher gas yield than was expected. Then, the higher temperatures are not suitable for bio-oil production. Char is also an interesting co-product for all pyrolysis temperatures.

The increasing environmental concerns and the significant growth of the waste to energy market calls for innovative and flexible technology that can effectively process and convert municipal solid waste into fuels and power at high efficiencies. To ensure the technical and economic feasibility of new technology, a sound understanding of the characteristics of the integrated energy system is essential. In this work, a comprehensive techno-economic analysis of a waste to power and heat plant based on integrated intermediate pyrolysis and CHP (Pyro-CHP) system was performed. The overall plant CHP efficiency was found to be nearly 60% defined as heat and power output compared to feedstock fuel input. By using an established economic evaluation model, the capital investment of a 5 tonne per hour plant was calculated to be 27.64 pound million and the Levelised Cost of Electricity was 0.063 pound/kWh. This agrees the range of cost given by the UK government. To maximise project viability, technology developers should endeavour to seek ways to reduce the energy production cost. Particular attention should be given to the factors with the greatest influence on the profitability, such as feedstock cost (or gate fee for waste), maintaining plant availability, improving energy productivity and reducing capital cost.

•Slow pyrolysis and anaerobic digestion were integrated for energy recovery from waste.•Aqueous pyrolysis liquids produced from OFMSW were screened in AD trials.•Pyrolysis temperature was key factor for liquid yield, energy content, toxicity and COD.•Organic pyrolysis liquids contain 18.9–63.0% of the product energy.•Aqueous product contains 1.2–13.1% of product energy and about 50% convertible to CH4.

Two anhydrosugar model compounds (cellobiose and levoglucosan) and a mixture of anhydrosugars from the fast pyrolysis of birch wood were subjected to acid hydrolysis using sulfuric acid as a catalyst. The anhydrosugar mixture or bio-oil aqueous fraction was found to contain mainly levoglucosan with a concentration of 30 g L-1. Hydrolysis temperature, reaction time, and catalyst to substrate molar ratios (c/s) were varied to identify their influence for glucose production. At 120 degrees C, 60 min, and a 0.9 c/s ratio, glucose yields of 98.55% and 96.56%, and substrate conversions of 100% and similar to 92%, were achieved when hydrolyzing cellobiose and levoglucosan, respectively. An increase in the temperature to 135 degrees C resulted in a decrease in both glucose yield and selectivity, whereas substrate conversions around 90% were maintained for both anhydrosugars. During the hydrolysis of the bio-oil fraction, a range of conditions to achieve glucose yields above 90% was depicted. It was found that c/s ratios between 0.17 and 0.90 and temperatures between 118 and 126 degrees C were suitable to achieve glucose yields around 100% (30 g L-1). Furthermore, glucose concentrations of similar to 117% (35 g L-1) and levoglucosan conversions above 90% were attained at 135 degrees C, 20 min, and a 0.2 estimated c/s ratio.

A thorough assessment has been made of the characteristics of bio-oil from fast pyrolysis of biomass. Fast pyrolysis uniquely gives high yields of a homogenous mobile liquid for direct use for heat and power and indirect use for biofuels and green chemicals. An improved understanding of the significance of the different aspects of quality of bio-oil helps to establish standards and key quality requirements which help to define limitations for use. An appreciation of the potential for bio-oil to meet a broad spectrum of applications in renewable energy has led to a significantly increased R&D activity in studying the science and technology of fast pyrolysis with increased emphasis on quality improvement. This increased activity is evident in North America, Europe and Asia with many new entrants as well as expansion of existing activities. The only disappointment is the continued limited industrial development and deployment of fast pyrolysis that are necessary to provide the basic bio-oil raw material for the development and exploitation of applications.

Combined heat and power from the intermediate pyrolysis of biomass materials offers flexible, on demand renewable energy with some significant advantages over other renewable routes. To maximise the deployment of this technology an understanding of the dynamics and sensitivities of such a system is required. In the present work the system performance, economics and life-cycle environmental impact is analysed with the aid of the process simulation software Aspen Plus. Under the base conditions for the UK, such schemes are not currently economically Competitive with energy and char products produced from conventional means. However, under certain scenarios as modelled using a sensitivity analysis this technology can compete and can therefore potentially contribute to the energy and resource sustainability of the economy, particularly in on-site applications with low-value waste feed-stocks. The major areas for potential performance improvement are in reactor cost reductions, the reliable use of waste feedstocks and a high value end use for the char by-product from pyrolysis. (C) 2017 Elsevier Ltd. All rights reserved.

This chapter provides a review of catalytic fast pyrolysis of biomass and its potential for improving fast pyrolysis oil quality. Catalytic pyrolysis focuses on the use of catalysts in a fast pyrolysis system processing biomass and/or waste materials for the production of bio-oil, liquid, and secondary products. As the development of sustainable energy and fuel sources is of growing concern, different approaches to pyrolysis are being considered to alleviate fears of climate change and fuel shortages. These are discussed in other chapters. This review describes the current catalytic fast pyrolysis field with particular focus on the effect of fast pyrolysis conditions on catalyst reactivity and life time. The different active solid materials that can be used within a pyrolysis system to improve pyrolysis oil are described and compared. Current reactor design and technology is also summarized.

The main driver for the investigation of fast pyrolysis oil marine fuel blends is EU directive 2012/33/EU which aims to cut the sulphur content of marine fuel and thereby reduce air pollution caused by marine vessels.The aim of this study was to investigate the miscibility of three‐ and four‐ component blends containing pyrolysis oil, 1‐butanol, biodiesel (RME) and/or marine gas oil (MGO). The ideal blend would be a stable homogenous product with a minimum amount of butanol, whilst maximising the amount of pyrolysis oil. A successful blend would have properties suitable for use in marine engines. In order to successfully utilise a marine fuel blend in commercial vessels it should meet minimum specification requirements such as a flash point ≥60°C.Blends of pyrolysis oil, RME, MGO and 1‐butanol were evaluated and characterised. The mixed blends were inspected after 48 hours for homogeneity and the results plotted on a tri‐plot phase diagram. Homogenous samples were tested for water content, pH, acid number, viscosity and flash point as these indicate a blend's suitability for engine testing.The work forms part of the ReShip Project which is funded by Norwegian industry partners and the Research Council of Norway (The ENERGIX programme). © 2016 American Institute of Chemical Engineers Environ Prog, 36: 677–684, 2017

Waste biomass is generated during the conservation management of semi-natural habitats, and represents an unused resource and potential bioenergy feedstock that does not compete with food production. Thermogravimetric analysis was used to characterise a representative range of biomass generated during conservation management in Wales. Of the biomass types assessed, those dominated by rush (Juncos effuses) and bracken (Pteridium aquilinum) exhibited the highest and lowest volatile compositions respectively and were selected for bench scale conversion via fast pyrolysis. Each biomass type was ensiled and a sub-sample of silage was washed and pressed. Demineralization of conservation biomass through washing and pressing was associated with higher oil yields following fast pyrolysis. The oil yields were within the published range established for the dedicated energy crops miscanthus and willow. In order to examine the potential a multiple output energy system was developed with gross power production estimates following valorisation of the press fluid, char and oil. If used in multi fuel industrial burners the char and oil alone would displace 3.9 x 10(5) tonnes per year of No. 2 light oil using Welsh biomass from conservation management. Bioenergy and product development using these feedstocks could simultaneously support biodiversity management and displace fossil fuels, thereby reducing GHG emissions. Gross power generation predictions show good potential. (C) 2016 Elsevier Ltd. All rights reserved.

Waste biomass is generated during the conservation management of semi-natural habitats, and represents an unused resource and potential bioenergy feedstock that does not compete with food production. Thermogravimetric analysis was used to characterise a representative range of biomass generated during conservation management in Wales. Of the biomass types assessed, those dominated by rush (Juncus effuses) and bracken (Pteridium aquilinum) exhibited the highest and lowest volatile compositions respectively and were selected for bench scale conversion via fast pyrolysis. Each biomass type was ensiled and a sub-sample of silage was washed and pressed. Demineralization of conservation biomass through washing and pressing was associated with higher oil yields following fast pyrolysis. The oil yields were within the published range established for the dedicated energy crops miscanthus and willow. In order to examine the potential a multiple output energy system was developed with gross power production estimates following valorisation of the press fluid, char and oil. If used in multi fuel industrial burners the char and oil alone would displace 3.9 10 tonnes per year of No. 2 light oil using Welsh biomass from conservation management. Bioenergy and product development using these feedstocks could simultaneously support biodiversity management and displace fossil fuels, thereby reducing GHG emissions. Gross power generation predictions show good potential. 2016 Elsevier Ltd. All rights reserved.

In this study, rice husk and corn stalk have been pyrolyzed in an auger pyrolysis reactor at pyrolysis temperatures of 350, 400, 450, 500, 550, and 600 °C in order to investigate the effect of the pyrolysis temperature on the pyrolysis performance of the reactor and physicochemical properties of pyrolysis products (this paper focuses on char and gas). The results have shown that the pyrolysis temperature significantly affects the mass yields and properties of the pyrolysis products. The mass yields of pyrolysis liquid and char are comparable to those reported for the same feedstocks processed in fluidized bed reactors. With the increase of the pyrolysis temperature, the pyrolysis liquid yield shows a peak at 500 °C, the char yield decreases, and the gas yield increases for both feedstocks. The higher heating value (HHV) and volatile matter content of char increase as the pyrolysis temperature increases from 350 to 600 °C. The gases obtained from the pyrolysis of rice husk and corn stalk mainly contain CO2, CO, CH4, H2, and other light hydrocarbons; the molar fractions of combustible gases increase and therefore their HHVs subsequently increase with the increase of the pyrolysis temperature.

The thermal processing of lignocellulosic material, for example by fast-pyrolysis, results in the formation of three fractions namely char, gases, and pyrolysis oil, the latter also referred to as bio-oil. The bio-oil composition depends upon the type of lignocellulosic material as well as pyrolysis conditions used, but in general is a mixture of acids, aldehydes, furans, phenols, water, and anhydrosugars. Among the anhydrosugars, 1, 6-anhydro-β-D-glucopyranose, commonly known as levoglucosan (LG), might be present in the bio-oil in major concentrations. LG can be converted via hydrolysis into monomeric sugar units such as glucose, which is a valuable chemical platform; for example it can be fermented to produce biofuels (ethanol and butanol). However the hydrolysis of LG into glucose is not a straightforward process, as it involves several parameters including temperature, residence time, catalyst type and acid catalyst to LG ratio. Normally liquid or solid acid catalysts are used to enhance the hydrolysis process and therefore to improve the glucose yield. The use of liquid acid catalysts such as sulfuric acid (H2SO4), encompasses several drawbacks as these liquid catalysts are difficult to recover and recycle, are environmentally unfriendly, represent a potential corrosion hazard, and might also promote the formation of by-products such as 5-hydroxymethyl furfural (5-HMF) and levulinic acid. On the other hand solid acid catalysts can be recovered by phase separation, are environmentally friendly and there are a wide range of catalysts available including acid zeolites, heteropolyacids (HPAs), polymer-based resins and, carbon-based. This research work will collate and evaluate information about research into existing solid acid catalysts to enhance the acid hydrolysis of anhydrosugars including LG and cellobiose into glucose. The results will lead to the selection of preferred catalysts based on their properties and influence during the hydrolysis process. The variation of the process parameters such as reaction time, temperature and type of catalyst, will be also considered and analysed for their impact in the glucose yield. Future studies will also include the influence of the substrate to catalyst ratio as well as other catalytic properties. This overview will form the basis of an experimental programme.

The kinetic parameters of the pyrolysis of miscanthus and its acid hydrolysis residue (AHR) were determined using thermogravimetric analysis (TGA). The AHR was produced at the University of Limerick by treating miscanthus with 5wt.% sulphuric acid at 175°C as representative of a lignocellulosic acid hydrolysis product. For the TGA experiments, 3 to 6g of sample, milled and sieved to a particle size below 250μm, were placed in the TGA ceramic crucible. The experiments were carried out under non-isothermal conditions heating the samples from 50 to 900°C at heating rates of 2.5, 5, 10, 17 and 25°C/min. The activation energy (EA) of the decomposition process was determined from the TGA data by differential analysis (Friedman) and three isoconversional methods of integral analysis (Kissinger–Akahira–Sunose, Ozawa–Flynn–Wall, Vyazovkin). The activation energy ranged from 129 to 156kJ/mol for miscanthus and from 200 to 376kJ/mol for AHR increasing with increasing conversion. The reaction model was selected using the non-linear least squares method and the pre-exponential factor was calculated from the Arrhenius approximation. The results showed that the best fitting reaction model was the third order reaction for both feedstocks. The pre-exponential factor was in the range of 5.6×1010 to 3.9×10+13min−1 for miscanthus and 2.1×1016 to 7.7×1025min−1 for AHR.

The present paper offers a methodological approach towards the estimation and definition of enthalpies constituting an energy balance around a fast pyrolysis experiment conducted in a laboratory scale fluid bed with a capacity of 1 kg/h. Pure N-2 was used as fluidization medium at atmospheric pressure and the operating temperature (similar to 500 degrees C) was adjusted with electrical resistors. The biomass feedstock type that was used was beech wood. An effort was made to achieve a satisfying 92.5% retrieval of products (dry basis mass balance) with the differences mainly attributed to loss of some bio-oil constituents into the quenching medium, ISOPAR (TM). The chemical enthalpy recovery for bio-oil, char and permanent gases is calculated 64.6%, 14.5% and 7.1%, respectively. All the energy losses from the experimental unit into the environment, namely the pyrolyser, cooling unit etc. are discussed and compared to the heat of fast pyrolysis that was calculated at 1123.5 kJ per kg of beech wood. This only represents 2.4% of the biomass total enthalpy or 6.5% its HHV basis. For the estimation of some important thermo-physical properties such as heat capacity and density, it was found that using data based on the identified compounds from the GC/MS analysis is very close to the reference values despite the small fraction of the bio-oil components detected. The methodology and results can help as a starting point for the proper design of fast pyrolysis experiments, pilot and/or industrial scale plants.