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This study explores the technical and economic potential of three Canadian biomass feedstocks (spruce, corn stover and wheat straw) to replace petro-diesel through the production of renewable diesel and gasoline via fast pyrolysis and hydroprocessing. A detailed data-intensive process and cost model for a 2000 dry t d−1 plant capacity for two scenarios (hydrogen production and hydrogen purchase) was developed using both experimental and published data. The authors analyzed the quality and quantity of bio-oil, which acts as an intermediate for renewable diesel, by performing fast pyrolysis experiments in a lab -scale fluidized bed reactor at temperatures of 400–520 °C and three particle size distributions. The production costs of renewable diesel are 0.98 $ L−1,1.11 $ L−1, 1.19 $ L−1, and 1.27 $ L−1 for the spruce hydrogen purchase, spruce hydrogen production, corn stover hydrogen production, and wheat straw hydrogen production scenarios, respectively. The net energy ratios (NERs) of the process, which is the ratio of the energy content of the output product to fossil fuel inputs, were calculated to be 2.16, 1.5, and 1.16 for spruce, corn stover, and wheat straw, respectively. The effects of byproduct selling price on renewable diesel cost were also investigated. As the results suggest, the yields of renewable diesel and gasoline depend on the amount of bio-oil produced through fast pyrolysis followed by the properties of biomass. From the sensitivity analysis, it is concluded that the cost of transportation fuel is most sensitive to bio-oil yield. As the NER for all three feedstocks is more than 1, it can be said that fast pyrolysis and hydroprocessing technology is energy sustainable. Finally, this pathway could be competitive with conventional transportation fuels if the revenue from the biochar can be generated. • Fast pyrolysis experiments were conducted for Canadian biomass feedstocks. • Process and cost models were developed for a 2000 t d−1 capacity fast pyrolysis and hydroprocessing unit. • The production cost of renewable diesel ranges from 0.98 to 1.27 $ L−1 • The effects of byproduct costs on renewable diesel cost were investigated. • A detailed sensitivity analysis and net energy ratios are presented. [ABSTRACT FROM AUTHOR]

Gasification has the potential to convert biomass into gaseous mixtures that can be used for hydrogen production. Thermal gasification and supercritical water gasification are commonly used thermochemical methods for conversion of biomass to hydrogen. Supercritical water gasification handles wet biomass, thus eliminating the capital cost-intensive drying step. Thermal gasification is considered as an alternative means of producing hydrogen from microalgae where biomass has to be dried before gasification. The authors developed techno-economic models for assessment of the production of hydrogen through supercritical gasification and thermal gasification processes. Techno-economic assessment was based on developed process models. Equipment was sized and costs were estimated using the developed process models, and the product value was determined assuming 20 years of plant life. The economic assessment of supercritical water and thermal gasification show that 2000 dry tonnes/day plant requires total capital investments of 277.8 M$ and 215.3 M$ for hydrogen product values of $4.59 ± 0.10/kg and $5.66 ± 0.10/kg, respectively. The relatively higher yield obtained in supercritical water gasification compared to thermal gasification results in lower product value of hydrogen for supercritical water gasification, thereby making it more desirable. This cost of hydrogen is about 4 times the cost of hydrogen from natural gas. The sensitivity analysis indicates that biomass cost and yield are the most sensitive parameters in the economics of the supercritical or thermal gasification process; this signifies the importance of algal biomass availability. The techno-economic assessment helps to identify options for the production of hydrogen fuel through these novel technologies. • The production of hydrogen from thermochemical algal conversion is assessed. • Data-intensive techno economic model is developed to determine the product value. • The cost of hydrogen from algal thermochemical processing varies from 4.59 to 5.66 $/kg. • The impact of CO 2 tipping fee on cost of hydrogen was assessed. [ABSTRACT FROM AUTHOR]

The economic feasibility of producing ammonia through the gasification of three different feedstocks produced in pulp and paper mills is investigated in this paper. The first case uses black liquor, the main by-product of the kraft pulping process, as the feedstock, and in the other two cases pulp sludge (PS) and waste sludge (WS) are co-gasified with black liquor. For all three cases, a process model in which mass and energy balances were calculated was developed. The model results were used to estimate the equipment size and estimate costs. Techno-economic models were developed and ammonia production costs were calculated. A case study for Alberta, a western Canadian province, was conducted. The results indicated that for a 10% discount rate (or internal rate of return [IRR]), ammonia production in all three cases is cost competitive with current ammonia prices. The cost of production (COP) of ammonia for all three cases ranges from 743 to 748 $/t. Sensitivity and uncertainty analyses were conducted on the estimated COP, and the results show that the COP is the most sensitive to the capital cost, discount rate, electricity price and plant lifetime. [ABSTRACT FROM AUTHOR]

Large resources are being invested globally in algae research in the anticipation that these microorganisms will become the “silver bullets” that lead to economic bio-renewable fuels, new food sources, and a host of high value products and simultaneously mitigate rising atmospheric CO 2 levels. A great deal of research has been completed on strains of algae with the potential to produce high lipid yields that make the biomass suitable for biofuel production. Many production systems for algae cultivation continue to be developed for moderate and hot climates (e.g., USA, Europe, and Australia). The largest algae cultivation systems to date use open pond systems. These autotrophic systems, however, have limited applicability in Canada’s northern climatic conditions. There is consensus that closed photobioreactor systems are required to control environmental conditions (including temperature), minimize evaporation and contamination, and augment the limited sunlight available during winter to generate consistent biomass yields for economically sustainable crops. Given the high capital and operating costs, however, many are skeptical that meaningful and economically sustainable algae cultivation can take place in Canada. This paper identifies nine scalable algae photobioreactor cultivation technologies that may suit Canadian northern climates. The information provides insights related to the developing algae industry in Canada as well as highlighting opportunities for further technological development specific to cold climates. Although the review demonstrates that exciting headway has been made, significant technological challenges remain and require that further innovations be developed. [ABSTRACT FROM AUTHOR]

The life cycle energy consumption and greenhouse gas (GHG) emission performances of forest biomass-derived oxymethylene ether (OME) synthesis used as a diesel additive are analyzed in this study. OME, a new alternative liquid fuel, has great miscibility with conventional fuels like diesel. OME can reduce combustion emissions significantly when used as a diesel additive without any modification to the engine. A data-intensive spreadsheet-based life cycle assessment (LCA) model was developed for OME synthesis from woodchips derived from two different kinds of forest biomass, whole tree and forest residue. Woodchip harvesting, chip transportation, chemical synthesis of OME from biomass-derived syngas, OME transportation to blending, and vehicle combustion of this transportation fuel were considered in the system boundary. The results show that the whole tree pathway produces 27 g CO 2 eq/MJ of OME, whereas the forest residue pathway produces 18 g CO 2 eq/MJ of OME over 20 years of plant life. The difference is mainly due to some emissions-intensive operations involved in biomass harvesting and biomass transportation such as skidding, road construction, etc., in the whole tree pathway. Also, vehicle combustion was found to be the most GHG-intensive unit for both pathways. OME combustion in a vehicle accounts for about 77% and 83% of the total life cycle GHG emissions for the whole tree and forest residue pathways, respectively. This study also compares the diesel life cycle emission numbers with the life cycle emissions of OME derived from forest biomass, and it was observed that GHG emissions can be reduced by 20–21% and soot (black carbon) emissions can be reduced by 30% using a 10% OME blended diesel as a transportation fuel compared with conventional diesel. [ABSTRACT FROM AUTHOR]

A process model was developed to determine the net energy ratio (NER) for the production of pellets from steam pretreated agricultural residue (wheat straw) and energy crops (i.e., switchgrass in this case). The NER is a ratio of the net energy output to the total net energy input from non-renewable energy sources into a system. Scenarios were developed to measure the effects of temperature and level of steam pretreatment on the NER of steam pretreated wheat straw and switchgrass pellets. The NERs for the base case at 6 kg h −1 are 1.76 and 1.37 for steam-pretreated wheat straw and switchgrass-based pellets, respectively. The reason behind the difference is that more energy is required to dry switchgrass pellets than wheat straw pellets. The sensitivity analysis for the model shows that the optimum temperature for steam pretreatment is 160 °C with 50% pretreatment (i.e. 50 % steam treated material is blended with the raw biomass and then pelletised). The uncertainty results for NER for steam pretreated wheat straw and switch grass pellets are 1.62 ± 0.10 and 1.42 ± 0.11, respectively. [ABSTRACT FROM AUTHOR]

The conversion of biomass for the production of liquid fuels can help reduce the greenhouse gas (GHG) emissions that are predominantly generated by the combustion of fossil fuels. Oxymethylene ethers (OMEs) are a series of liquid fuel additives that can be obtained from syngas, which is produced from the gasification of biomass. The blending of OMEs in conventional diesel fuel can reduce soot formation during combustion in a diesel engine. In this research, a process for the production of OMEs from woody biomass has been simulated. The process consists of several unit operations including biomass gasification, syngas cleanup, methanol production, and conversion of methanol to OMEs. The methodology involved the development of process models, the identification of the key process parameters affecting OME production based on the process model, and the development of an optimal process design for high OME yields. It was found that up to 9.02 tonnes day −1 of OME 3 , OME 4 , and OME 5 (which are suitable as diesel additives) can be produced from 277.3 tonnes day −1 of wet woody biomass. Furthermore, an optimal combination of the parameters, which was generated from the developed model, can greatly enhance OME production and thermodynamic efficiency. This model can further be used in a techno-economic assessment of the whole biomass conversion chain to produce OMEs. The results of this study can be helpful for petroleum-based fuel producers and policy makers in determining the most attractive pathways of converting bio-resources into liquid fuels. [ABSTRACT FROM AUTHOR]

Displacement of fossil fuel-based power through biomass co-firing could reduce the greenhouse gas (GHG) emissions from fossil fuels. In this study, data-intensive techno-economic models were developed to evaluate different co-firing technologies as well as the configurations of these technologies. The models were developed to study 60 different scenarios involving various biomass feedstocks (wood chips, wheat straw, and forest residues) co-fired either with coal in a 500 MW subcritical pulverized coal (PC) plant or with natural gas in a 500 MW natural gas combined cycle (NGCC) plant to determine their technical potential and costs, as well as to determine environmental benefits. The results obtained reveal that the fully paid-off coal-fired power plant co-fired with forest residues is the most attractive option, having levelized costs of electricity (LCOE) of $53.12–$54.50/MW h and CO 2 abatement costs of $27.41–$31.15/tCO 2 . When whole forest chips are co-fired with coal in a fully paid-off plant, the LCOE and CO 2 abatement costs range from $54.68 to $56.41/MW h and $35.60 to $41.78/tCO 2 , respectively. The LCOE and CO 2 abatement costs for straw range from $54.62 to $57.35/MW h and $35.07 to $38.48/tCO 2 , respectively. [ABSTRACT FROM AUTHOR]

Minimum production cost and optimum plant size are determined for pellet plants for three types of biomass feedstock – forest residue, agricultural residue, and energy crops. The life cycle cost from harvesting to the delivery of the pellets to the co-firing facility is evaluated. The cost varies from 95 to 105 $ t −1 for regular pellets and 146–156 $ t −1 for steam pretreated pellets. The difference in the cost of producing regular and steam pretreated pellets per unit energy is in the range of 2–3 $ GJ −1 . The economic optimum plant size (i.e., the size at which pellet production cost is minimum) is found to be 190 kt for regular pellet production and 250 kt for steam pretreated pellet. Sensitivity and uncertainty analyses were carried out to identify sensitivity parameters and effects of model error. [ABSTRACT FROM AUTHOR]

A process model was developed to determine the net energy ratio (NER) for both regular and steam-pretreated pellet production from ligno-cellulosic biomass. NER is a ratio of the net energy output to the total net energy input from non-renewable energy source into the system. Scenarios were developed to measure the effect of temperature and level of steam pretreatment on the NER of both production processes. The NER for the base case at 6 kg h −1 is 1.29 and 5.0 for steam-pretreated and regular pellet production respectively. However, at the large scale NER would improve. The major factor for NER is energy for steam and drying unit. The sensitivity analysis for the model shows that the optimum temperature for steam pretreatment is 200 °C with 50% pretreatment (Steam pretreating 50% feed stock, while the rest is undergoing regular pelletization). Uncertainty result for steam pretreated and regular pellet is 1.35 ± 0.09 and 4.52 ± 0.34 respectively. [ABSTRACT FROM AUTHOR]

Abstract: Drying biomass as fuel in a combustion process can increase the combustion efficiency, reduce pollution and improve operation. On the other hand, drying biomass is an expensive process that requires huge capital investment and energy input. The difficulty of removing moisture from biomass is affected by many factors such as the moisture content and the size of the solid particles. The level of drying is therefore a very important parameter, which strongly influences the economies of the utilization of biofuel. This study utilizes a mathematical model that incorporates material and energy balances, heat transfer and drying kinetics to determine the optimum drying level of biomass. Drying kinetic based upon the Fick's second law of diffusion is used in the model to determine the energy and capital expenditures for the drying process. Case studies of wood chips drying are presented to demonstrate how the thickness of wood chips affects the optimal drying intensity and the overall economics of the process. [Copyright &y& Elsevier]

Abstract: Bamboo is the world''s fastest growing woody plant and some species can grow up to a foot a day if the right conditions were met, therefore it can be a sustainable raw material resource for energy demand. In Asia, bamboo is mainly used for scaffolding and about 50,000tonnes of bamboo waste is generated annually in Hong Kong. To utilise the growing bamboo waste, pyrolysis which is a promising technology for tackling waste disposal can be employed. This paper proposes the pyrolysis mechanism and develops a mathematical model for bamboo pyrolysis process using the parameters generated from the TGA/DTA analysis. This model helps to understand the bamboo pyrolysis better and it was then used to study the effects of different operating parameters on bamboo pyrolysis. [Copyright &y& Elsevier]

Biomass can be converted to coal-like products known as hydrochar or biochar. Raw biomass generally has high moisture content. Wet torrefaction has gained considerable interest recently because of the unique characteristics of processing high-moisture content to a solid coal-like product. Five biomass feedstocks – wheat straw, pine, grape pomace, animal manure, and algae – were analyzed. The characteristics, as well as mass and energy yields of hydrochars and biochars from these feedstocks, were compared. Process simulation models were developed for both processes for each feedstock and techno-economic assessments conducted. The results indicate that hydrochars have superior characteristics, more coal-like properties, lower yields, and a higher cost of production (COP) than biochars for all cases except the pathways using manure as feedstock, where hydrochar COP is lower. The lowest production costs (without carbon credit) can be achieved through dry and wet torrefaction of grape pomace at 2.29 $/GJ and 4.14 $/GJ, respectively. Sensitivity and uncertainty analyses were also conducted for all pathways to understand the effects on production cost of varying different technical and economic factors. The results of this study will provide valuable insights into coal alternative products, especially in jurisdictions (like Alberta, Canada) planning to phase out coal plants. • Biocoal production via wet (WT) and dry (DT) torrefaction processes is investigated. • Five feedstocks (wheat straw, pine, grape pomace, manure, and algae) are studied. • Mass and energy yields and production costs (w and w/o carbon credit) are assessed. • Cost of biocoal production (COP) is competitive with coal price in some pathways. • Grape pomace has the lowest COP at 2.30 $/GJ and 4.15 $/GJ for DT and WT processes, respectively. [ABSTRACT FROM AUTHOR]

Bio-oil, produced through fast pyrolysis, can act as an intermediate, which can be further upgraded to biofuels. Fast pyrolysis is done in either a centralized or a decentralized (mobile pyrolysis system [MPS]) system. In a centralized system, biomass is transported to a plant to produce bio-oil, which is upgraded in the same unit, while in a decentralized system, the mobile plant is moved to the forest to produce bio-oil, which is transported to an upgrading facility. The objective of this study is to develop supply chain models and conduct a techno-economic assessment of bio-oil production in these two systems using the developed models. For both systems, the bio-oil plant capacity is considered to be 2000 dry t d−1. Because the capacity of an MPS ranges from 10 to 100 dry t d−1, several mobile pyrolysis units are required to achieve the target bio-oil produced in the base case capacity. In this study, models were developed for each supply chain network allocation scenario/configuration for MPS site location (the radial scenario and the truncated scenario) and four relocation time scenarios were assumed (yearly, semi-annually, quarterly, and monthly). Then, bio-oil production costs were evaluated and compared those with a centralized plant. For a 2000 dry t d−1 biomass plant, bio-oil production costs are 0.241$ L−1, 0.349 $ L−1, and 0.407 $ L−1 for the centralized plant, the MPS truncated scenario (100 dry t d−1 MPS unit, yearly relocation), and the MPS radial scenario (100 dry t d−1 MPS unit, yearly relocation), respectively. • Centralized and mobile pyrolysis systems (MPS) were investigated to produce bio-oil. • The capacity of an MPS unit ranged from 10 to 100 dry t d−1. • For an MPS, two allocation scenarios were considered: radial and truncated. • Bio-oil production costs for the two systems were assessed and compared. • The base case plant capacity was varied for both systems. [ABSTRACT FROM AUTHOR]

This study explores the hydrothermal liquefaction (HTL) of wood chips to biocrude followed by upgrading to diluents, which are used to transport bitumen through pipelines. In this study, we considered a 2000 dry t day−1 plant capacity with two scenarios. The first scenario uses hydrogen for upgrading from the on-site hydrogen production plant (i.e., the hydrogen production scenario) and the other relies on procuring hydrogen from an external source (i.e., the hydrogen purchase scenario). We developed a data-intensive process model for HTL and used it to estimate plant capital costs. Project investment costs for the hydrogen production and hydrogen purchase scenarios are 559.67 and 429.13 M $, respectively. The product values (PV) of the diluent from the two scenarios are 0.98 ± 0.03 and 0.79 ± 0.03 $ L−1, respectively, at a 95% confidence interval. The sensitivity analysis shows that diluent yield and internal rate of return (IRR) have the highest impact on the PV of the diluent, followed by capital cost and biomass cost. The optimum plant size at which the cost of production is lowest is 4000 dry t day−1 for PVs of 0.82 $ L−1 and 0.68 $ L−1 for the hydrogen production and purchase scenarios, respectively. This study offers insights into the techno-economic feasibility of producing diluents from HTL. The results of the study could help in the production of diluents for bitumen transportation for the oil sands industry and help reduce the overall greenhouse gas (GHG) footprint of the oil and gas sector. © 2017 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]

Abstract: Foreseeing a promising future of utilizing bio-energy, more and more small-scale biomass power plants are recently built. Biomasses with high moisture content such as sludge or Empty Fruit Bunch are often used as fuel in small-scale power plant without proper drying. These highly moist biomasses reduce the efficiency of the boiler but on the other hand drying the biofuel is also an energy intensive process. This paper aims to investigate how drying would affect the overall energy efficiency while proper heat integration in between the drying and power plant is under consideration. A 12.5 MW biomass power plant that burns EFB with 60 wt% moisture is used as a base case. Two types of dryer, Hot Air Dryer (HAD) and Superheated Steam Dryer (SSD), are proposed for the drying process. These two dryers require heat at different temperature levels to provide a better chance for heat integration. Material and energy balance models of the dryers and boilers are derived in this paper and the steam power plant model is constructed in Aspen Plus. The results of this study show that with proper drying and heat integration, the overall efficiency can be improved by more than 5%, when compared to process without drying. [Copyright &y& Elsevier]

This study develops life cycle water footprints for the production of fuels and chemicals via thermochemical conversion of algae biomass. This study is based on two methods of feedstock production – ponds and photobioreactors (PBRs) – and four conversion pathways – fast pyrolysis, hydrothermal liquefaction (HTL), conventional gasification, and hydrothermal gasification (HTG). The results show the high fresh water requirement for algae production and the necessity to recycle harvested water or use alternative water sources. To produce 1 kg of algae through ponds, 1564 L of water are required. When PBRs are used, only 372 L water are required; however, the energy requirements for PBRs are about 30 times higher than for ponds. From a final product perspective, the pathway based on the gasification of algae biomass was the thermochemical conversion method that required the highest amount of water per MJ produced (mainly due to its low hydrogen yield), followed by fast pyrolysis and HTL. On the other hand, HTG has the lowest water footprint, mainly because the large amount of electricity generated as part of the process compensates for the electricity used by the system. Performance in all pathways can be improved through recycling channels. [ABSTRACT FROM AUTHOR]