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1.
Process to process material and heat integration strategies for bio-oil integrated gasification and methanol synthesis (BOIG-MeOH) systems were developed to assess their technological and economic feasibility. Distributed bio-oil generations and centralised processing enhance resource flexibility and technological feasibility. Economic performance depends on the integration of centralised BOIG-MeOH processes, investigated for cryogenic air separation unit (ASU) and water electrolyser configurations. Design and operating variables of gasification, heat recovery from gases, water and carbon dioxide removal units, water-gas shift and methanol synthesis reactors and CHP network were analysed to improve the overall efficiency and economics. The efficiency of BOIG-MeOH system using bio-oil from various feedstocks was investigated. The system efficiency primarily attributed by the moisture content of the raw material decreases from oilseed rape through miscanthus to poplar wood. Increasing capacity and recycle enhances feasibility, e.g.1350 MW BOIG-MeOH with ASU and 90% recycle configuration achieves an efficiency of 61.5% (methanol, low grade heat and electricity contributions by 89%, 7.9% and 3% respectively) based on poplar wood and the cost of production (COP) of methanol of 318.1 Euro/t for the prices of bio-oil of 75 Euro/t and electricity of 80.12 Euro/MWh, respectively. An additional transportation cost of 4.28-8.89 Euro/t based on 100 km distance between distributed and centralised plants reduces the netback of bio-oil to 40.9-36.3 Euro/t.  相似文献   

2.
This paper evaluates the economic feasibility of biohydrogen production via two bio-oil processing pathways: bio-oil gasification and bio-oil reforming. Both pathways employ fast pyrolysis to produce bio-oil from biomass stock. The two pathways are modeled using Aspen Plus® for a 2000 t d−1 facility. Equipment sizing and cost calculations are based on Aspen Economic Evaluation® software. Biohydrogen production capacity at the facility is 147 t d−1 for the bio-oil gasification pathway and 160 t d−1 for the bio-oil reforming pathway. The biomass-to-fuel energy efficiencies are 47% and 84% for the bio-oil gasification and bio-oil reforming pathways, respectively. Total capital investment (TCI) is 435 million dollars for the bio-oil gasification pathway and is 333 million dollars for the bio-oil reforming pathway. Internal rates of return (IRR) are 8.4% and 18.6% for facilities employing the bio-oil gasification and bio-oil reforming pathways, respectively. Sensitivity analysis demonstrates that biohydrogen price, biohydrogen yield, fixed capital investment (FCI), bio-oil yield, and biomass cost have the greatest impacts on facility IRR. Monte-Carlo analysis shows that bio-oil reforming is more economically attractive than bio-oil gasification for biohydrogen production.  相似文献   

3.
The need for flexible power plants could increase in the future as variable renewable energy (VRE) share will increase in the power grid. These power plants could balance the increasing strain on electricity grids by renewables. The proposed plant in this paper can adapt to these ramps in electricity demand of the power grid by maintaining a constant feed and producing also high purity hydrogen. Dry methane reforming (DMR) is incorporated into a flexible power plant model and the key performance indicators are calculated from a techno-economic perspective. The net output of the plant is 450 MW with the possibility to lower power production and produce hydrogen, maintaining a high CO2 capture rate (72%). Two cases are compared to the base case to quantify: (i) energy and cost penalties for CO2 capture and (ii) advantages of flexible power plant operation. The levelized cost of electricity (LCOE) for the base case is 67 Euro/MWh, the addition of a carbon capture unit increases it to 82 Euro/MWh. In the case of flexible operation, both the LCOE and levelized cost of hydrogen (LCOH) are calculated and the two depend on the cost allocation factor. The LCOE ranges from 65 to 85 Euro/MWh while the LCOH from 0.15 to 0.073 Euro/Nm3. The DMR power plant presented in Cases 1 and 2 present little advantages in today's market conditions however, the flexible plant (Case 3) can be viable option in balancing VRE.  相似文献   

4.
Integration/co-firing with existing fossil fuel plants could give near term highly efficient and low cost power production from biomass. This paper presents a techno-economical analysis on options for integrating biomass thermal conversion (optimized for local resources ∼50 MWth) with existing CCGT (combined cycle gas turbine) power plants (800–1400 MWth). Options include hybrid combined cycles (HCC), indirect gasification of biomass and simple cycle biomass steam plants which are simulated using the software Ebsilon Professional and Aspen Plus. Levelized cost of electricity (LCoE) is calculated with cost functions derived from power plant data. Results show that the integrated HCC configurations (fully-fired) show a significantly higher efficiency (40–41%, LHV (lower heating value)) than a stand-alone steam plant (35.5%); roughly half of the efficiency (2.4% points) is due to more efficient fuel drying. Because of higher investment costs, HCC options have cost advantages over stand-alone options at high biomass fuel prices (>25 EUR/MWh) or low discount rates (<5%). Gasification options show even higher efficiency (46–50%), and the lowest LCoE for the options studied for fuel costs exceeding 10 EUR/MWh. It can be concluded that clear efficiency improvements and possible cost reductions can be reached by integration of biomass with CCGT power plants compared to stand-alone plants.  相似文献   

5.
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.  相似文献   

6.
Straw and corn stover can be used to produce ethanol by enzymatic hydrolysis and fermentation, or syndiesel by oxygen gasification and Fischer Tropsch (FT) reaction. FT has a higher processing cost and a higher energy yield of liquid transportation fuel. We analyze the cost of produced liquid fuel as a function of the field cost of biomass. At 80 $ t?1 (dry basis) a crossover point is reached. Below this value, the cost of producing energy as ethanol is lower; above this value, FT syndiesel is lower. However, the crossover point occurs at a very high field cost of biomass, more than 5.50 $ GJ?1, and ethanol plants are less capital intense than FT and hence have a smaller economic size. For both reasons ethanol is likely to be the preferred processing alternative.  相似文献   

7.
This paper aims to provide insights in the cost developments of offshore wind energy in Europe. This is done by analysing 46 operational offshore wind farms commissioned after 2000. An increase of the Capital Expenditures (CAPEX) is found that is linked to the distance to shore and depth of more recent wind farms and commodity prices. Analysis results indicate that these two factors are only responsible for about half of the observed CAPEX increase, suggesting other factors such as turbine market with limited competition also led to an increasing CAPEX. Using CAPEX, Annual Energy Production, Financings costs and Operational Expenditures, the development of average Levelized Cost of Electricity (LCoE) is shown to increase from 120 €/MWh in 2000 towards 190 €/MWh in 2014, which is a direct result of the CAPEX increase. The results indicate very different LCoE values among European countries, from currently about 100 Euro/MWh in Denmark and Sweden to 150-220 Euro/MWh in all other countries investigated suggesting an effect of national policy frameworks on the LCoE of offshore wind energy.  相似文献   

8.
The demand for biofuels and biochemicals is expected to increase in the future, which will in turn increase the demand for biomass feedstock. Large gasification plants fueled with biomass feedstock are likely to be a key enabling technology in a resource‐efficient, bio‐based economy. Furthermore, the costs for producing biofuels and biochemicals in such plants could potentially be decreased by utilizing inexpensive low‐grade residual biomass as feedstock. This study investigates the usage of shredded tree bark as a feedstock for the production of biomethane in the GoBiGas demonstration plant in Gothenburg, Sweden, based on a 32 MWth industrial dual fluidized bed gasification unit. The plant was operated with bark feedstock for 12 000 hours during the period 2014 to 2018. Data from the measurement campaign were processed using a stochastic approach to establish the plant's mass and energy balances, which were then compared with operation of the plant with wood pellets. For this comparison, an extrapolation algorithm was developed to predict plant performance using bark dried to the same moisture content as wood pellets, ie, 8%w.b. Plant operation with bark feedstock was evaluated for operability, efficiency, and feedstock‐related cost. The gas quality achieved during the test period was similar to that obtained for operation with wood pellets. Furthermore, no significant ash sintering or agglomeration problems were observed more than 750 hours of operation. The calculated biomass‐to‐biomethane efficiency is 43% to 47% (lower heating value basis) for operation with wet bark. However, the predicted biomass‐to‐biomethane efficiency can be increased to 55%–65% for operation with bark feedstock dried to 8% moisture content, with corresponding feedstock costs in the range of 24.2 to 32.7 EUR/MWh; ie, a cost reduction of about 40% compared with wood pellets.  相似文献   

9.
J.P. Reichling 《Energy》2011,36(11):6529-6535
Use of agricultural biomass (switchgrass, prairie grasses) through Fischer-Tropsch (FT) conversion to liquid fuels is compared with biomass utilization via (IGCC) integrated gasification combined cycle electrical production. In the IGCC scenario, biomass is co-fired with coal, with biomass comprising 10% of the fuel input by energy content. In this case, the displaced coal is processed via FT methods so that liquid fuels are produced in both scenarios. Overall performance of the two options is compared on the basis of total energy yield (electricity, liquid fuels), carbon dioxide emissions, and total cost. Total energy yield is almost identical whether biomass is used for electrical power generation or liquid fuels synthesis. Carbon dioxide emissions are also approximately equal for the two pathways. Capital costs are more difficult to compare since scaling factors cause considerable uncertainty. With IGCC costs roughly equivalent for either scenario, cost differences between the pathways appear based on FT plant construction cost. Coal FT facility capital cost estimates for the plant scale in this study (721 MWt LHV input) are estimated to be 410 (MUSD) million US Dollars while the similar scale biomass-only FT plant costs range from 430 MUSD to 590 MUSD.  相似文献   

10.
Biomass gasification is considered a key technology in reaching targets for renewable energy and CO2 emissions reduction. This study evaluates policy instruments affecting the profitability of biomass gasification applications integrated in a Swedish district heating (DH) system for the medium-term future (around year 2025). Two polygeneration applications based on gasification technology are considered in this paper: (1) a biorefinery plant co-producing synthetic natural gas (SNG) and district heat; (2) a combined heat and power (CHP) plant using integrated gasification combined cycle technology. Using an optimisation model we identify the levels of policy support, here assumed to be in the form of tradable certificates, required to make biofuel production competitive to biomass based electricity generation under various energy market conditions. Similarly, the tradable green electricity certificate levels necessary to make gasification based electricity generation competitive to conventional steam cycle technology, are identified. The results show that in order for investment in the SNG biorefinery to be competitive to investment in electricity production in the DH system, biofuel certificates in the range of 24–42 EUR/MWh are needed. Electricity certificates are not a prerequisite for investment in gasification based CHP to be competitive to investment in conventional steam cycle CHP, given sufficiently high electricity prices. While the required biofuel policy support is relatively insensitive to variations in capital cost, the required electricity certificates show high sensitivity to variations in investment costs. It is concluded that the large capital commitment and strong dependency on policy instruments makes it necessary that DH suppliers believe in the long-sightedness of future support policies, in order for investments in large-scale biomass gasification in DH systems to be realised.  相似文献   

11.
This study uses Geographical Information Systems (GIS) to estimate woody biomass supply and demand in Northeast Italy. Demand is estimated using census data on boilers and supply calculations are derived from data on timber harvests and mill operations. The analysis is done with GIS using Large Scale Analysis at a broader resolution (for the entire region) and Small Scale Analysis at a finer resolution (for the Primiero valley only), with added information on tree species, road networks and logging systems. From large scale analysis demand results to be about 163 000 MWh, corresponding to about 71 000 tonnes per year of fuel, with a moisture content of 50 percent. As shown by results from a small scale analysis, the Primiero valley has a deficit of 21 400 MWh. A more thorough analysis shows that 93 percent of logging operations can be performed with cable cranes and that high quality chips derived from forest biomass amount to only 335 MWh of energy (20 percent of the total). The deficit calculated at a small scale confirms the value obtained in the large scale calculation.Analysis of the demand-supply balance will be helpful for decision makers and politicians and should be taken into account when allocating subsidies for new boilers or district heating.  相似文献   

12.
Short rotation coppice (SRC) seems attractive as an energy crop on degraded land. Gasification and flash pyrolysis are promising technologies for the conversion of SRC into energy or chemicals. A model has been developed to calculate the net present value (NPV) of the cash flows generated by an investment in gasification or flash pyrolysis of SRC for the production of electricity or for combined heat and power production. The NPV has been calculated and compared for (combined heat and) power stations with an electrical capacity (Pe) between 5 MW and 20 MW. Furthermore the minimal amount of heat that has to be sold to make combined heat and power production more profitable than pure electricity production has been determined. By performing Monte Carlo simulations, key variables that influence the NPV have been identified.In the case of small scale SRC conversion, i.e. at an electrical capacity of 5 MW-10 MW, flash pyrolysis is more profitable than gasification. At the smallest scale of 5 MW it is necessary to invest in combined heat and power production, as the sole production of electricity is not profitable at this low scale. At an electrical capacity of 10 MW flash pyrolysis for the sole production of electricity becomes profitable, but gasification for electricity production is still not viable. At this capacity however, the extra investments required in the case of combined heat and power production are already paid back if only 25% of the produced heat can be sold. At a higher capacity of 20 MW, the technology choice becomes unclear taking into account the most uncertain variables, i.e. investment cost parameters and energetic efficiencies.  相似文献   

13.
In this paper, a conceptual hybrid biomass gasification system is developed to produce hydrogen and is exergoeconomically analyzed. The system is based on steam biomass gasification with the lumped solid oxide fuel cell (SOFC) and solid oxide electrolyser cell (SOEC) subsystem as the core components. The gasifier gasifies sawdust in a steam medium and operates at a temperature range of 1023-1423 K and near atmospheric pressure. The analysis is conducted for a specific steam biomass ratio of 0.8 kmol-steam/kmol-biomass. The gasification process is assumed to be self-thermally standing. The pressurized SOFC and SOEC are of planar types and operate at 1000 K and 1.2 bar. The system can produce multi-outputs, such as hydrogen (with a production capacity range of 21.8-25.2 kgh−1), power and heat. The internal hydrogen consumption in the lumped SOFC-SOEC subsystem increases from 8.1 to 8.6 kg/h. The SOFC performs an efficiency of 50.3% and utilizes the hydrogen produced from the steam that decomposes in the SOEC. The exergoeconomic analysis is performed to investigate and describe the exergetic and economic interactions between the system components through calculations of the unit exergy cost of the process streams. It obtains a set of cost balance equations belonging to an exergy flow with material streams to and from the components which constitute the system. Solving the developed cost balance equations provides the cost values of the exergy streams. For the gasification temperature range and the electricity cost of 0.1046 $/kWh considered, the unit exergy cost of hydrogen ranges from 0.258 to 0.211 $/kWh.  相似文献   

14.
We demonstrated an auto-thermal reforming process for producing hydrogen from biomass pyrolysis liquids. Using a noble metal catalyst (0.5% Pt/Al2O3 from BASF) at a methane-equivalent space velocity of around 2000 h−1, a reformer temperature of 800 °C–850 °C, a steam-to-carbon ratio of 2.8–4.0, and an oxygen-to-carbon ratio of 0.9–1.1, we produced 9–11 g of hydrogen per 100 g of fast pyrolysis bio-oil, which corresponds to 70%–83% of the stoichiometric potential. The elemental composition of bio-oil and the bio-oil carbon-to-gas conversion, which ranged from 70% to 89%, had the most significant impact on the yield of hydrogen. Because of incomplete volatility the remaining 11%–30% of bio-oil carbon formed deposits in the evaporator. Assuming the same process efficiency as that in the laboratory unit, the cost of hydrogen production in a 1500 kg/day plant was estimated at $4.26/kg with the feedstock, fast pyrolysis bio-oil, contributing 56.3% of the production cost.  相似文献   

15.
Distributed waste-to-hydrogen (WtH) systems are a potential solution to tackle the dual challenges of sustainable waste management and zero emission transport. Here we propose a concept of distributed WtH systems based on gasification and fermentation to support hydrogen fuel cell buses in Glasgow. A variety of WtH scenarios were configured based on biomass waste feedstock, hydrogen production reactors, and upstream and downstream system components. A cost-benefit analysis (CBA) was conducted to compare the economic feasibility of the different WtH systems with that of the conventional steam methane reforming-based method. This required the curation of a database that included, inter alia, direct cost data on construction, maintenance, operations, infrastructure, and storage, along with indirect cost data comprising environmental impacts and externalities, cost of pollution, carbon taxes and subsidies. The levelized cost of hydrogen (LCoH) was calculated to be 2.22 GB P/kg for municipal solid waste gasification and 2.02 GB P/kg for waste wood gasification. The LCoHs for dark fermentation and combined dark and photo fermentation systems were calculated to be 2.15 GB P/kg and 2.29 GB P/kg. Sensitivity analysis was conducted to identify the most significant influential factors of distributed WtH systems. It was indicated that hydrogen production rates and CAPEX had the largest impact for the biochemical and thermochemical technologies, respectively. Limitations including high capital expenditure will require cost reduction through technical advancements and carbon tax on conventional hydrogen production methods to improve the outlook for WtH development.  相似文献   

16.
Biomass gasification is an important method to obtain renewable hydrogen. However, this technology still stagnates in a laboratory scale because of its high-energy consumption. In order to get maximum hydrogen yield and decrease energy consumption, this study applies a self-heated downdraft gasifier as the reactor and uses char as the catalyst to study the characteristics of hydrogen production from biomass gasification. Air and oxygen/steam are utilized as the gasifying agents. The experimental results indicate that compared to biomass air gasification, biomass oxygen/steam gasification improves hydrogen yield depending on the volume of downdraft gasifier, and also nearly doubles the heating value of fuel gas. The maximum lower heating value of fuel gas reaches 11.11 MJ/N m3 for biomass oxygen/steam gasification. Over the ranges of operating conditions examined, the maximum hydrogen yield reaches 45.16 g H2/kg biomass. For biomass oxygen/steam gasification, the content of H2 and CO reaches 63.27–72.56%, while the content of H2 and CO gets to 52.19–63.31% for biomass air gasification. The ratio of H2/CO for biomass oxygen/steam gasification reaches 0.70–0.90, which is lower than that of biomass air gasification, 1.06–1.27. The experimental and comparison results prove that biomass oxygen/steam gasification in a downdraft gasifier is an effective, relatively low energy consumption technology for hydrogen-rich gas production.  相似文献   

17.
The potential of grid-connected solar PV system in Bangladesh was estimated utilizing GeoSpatial toolkit, NASA SSE solar radiation data and HOMER optimization software. Financial viability of solar photovoltaic as an electricity generation source for Bangladesh was also assessed utilizing a proposed 1-MW grid-connected solar PV system using RETScreen simulation software for 14 widespread locations in Bangladesh. The technical potential of gird-connected solar PV in Bangladesh was calculated as about 50174 MW. The annual electricity generation of the proposed system varied depending on the location between 1653 MWh and 1854 MWh, with a mean value of 1729 MWh. Several different economic and financial indicators were calculated, such as the internal rate of return, net present value, benefit-cost ratio, cost of energy production and simple payback. All indicators – for all sites – showed favorable condition for development of the proposed solar PV system in Bangladesh. The results also showed that a minimum of 1423 tons of greenhouse gas emissions can be avoided annually utilizing the proposed system at any part of the country.  相似文献   

18.
Large-scale systems suitable for the production of synthetic natural gas (SNG), methanol or gasoline (MTG) are examined using a self-consistent design, simulation and cost analysis framework. Three basic production routes are considered: (1) production from biomass via gasification; (2) from carbon dioxide and electricity via water electrolysis; (3) from biomass and electricity via hybrid process combining elements from routes (1) and (2). Process designs are developed based on technologies that are either commercially available or successfully demonstrated at precommercial scale. The prospective economics of future facilities coproducing fuels and district heat are evaluated from the perspective of a synthetic fuel producer. The levelised production costs range from 18–37 €/GJ for natural gas, 21–40 €/GJ for methanol and 23–48 €/GJ for gasoline, depending on the production route. For a given end-product, the lowest costs are associated with thermochemical plant configurations, followed by hybrid and electrochemical plants.  相似文献   

19.
The investment costs of water electrolysis represent one key challenge for the realisation of renewable hydrogen-based energy systems. This work presents a technology cost assessment and outlook towards 2030 for alkaline electrolysers (AEL) and PEM electrolysers (PEMEL) in the MW to GW range taking into consideration the effects of plant size and expected technology developments. Critical selected data was fitted to a modified power law to describe the cost of an electrolyser plant based on the overall capacity and a learning/technology development rate to derive cost estimations for different PEMEL and AEL plant capacities towards 2030. The analysis predicts that the CAPEX gap between AEL and PEMEL technologies will decrease significantly towards 2030 with plant size until 1–10 MW range. Beyond this, only marginal cost reductions can be expected with CAPEX values approaching 320–400 $/kW for large scale (greater than 100 MW) plants by 2030 with subsequent cost reductions possible. Learning rates for electrolysers were estimated at 25–30% for both AEL and PEMEL, which are significantly higher than the learning rates reported in previous literature.  相似文献   

20.
High efficient production of lower alcohols (C1–C5 mixed alcohols) from hydrogen rich bio-oil derived syngas was achieved in this work. A non-catalytic partial oxidation (NPOX) gasification technology was successfully applied in the production and conditioning of bio-oil derived syngas using bio-oil (BO) and emulsifying waste engine oil (EWEO) as feedstock. The effects of water addition and feedstock composition on the gasification performances were investigated. When the BO20 and EWEO30 was mixed with mass ratio of 1: 0.33, the maximum hydrogen yield of 93.7% with carbon conversion of 96.7% was obtained, and the hydrogen rich bio-oil derived syngas was effectively produced. Furthermore, a two-stage bed reactor was applied in the downstream process of lower alcohols synthesis from hydrogen rich bio-oil derived syngas (H2/CO/CO2/CH4/N2 = 52.2/19.5/3.0/9.4/15.9, v/v). The highest carbon conversion of 42.5% and the maximum alcohol yield of 0.18 kg/kgcat h with selectivity of 53.8 wt% were obtained over the Cu/ZnO/Al2O3(2.5)//Cu25Fe22Co3K3/SiO2(2.5) catalyst combination system. The mechanism and evaluation for lower alcohols synthesis from model bio-oil derived syngas and model mixture gas were also discussed. The integrative process of hydrogen rich bio-oil derived syngas production and downstream lower alcohols synthesis, potentially providing a promising route for the conversion of organic wastes into high performance fuels and high value-added chemicals.  相似文献   

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