Domestic production of bioenergy by utilizing set-aside land in Taiwan can reduce Taiwan’s reliance on expensive and politically insecure foreign fossil fuels while also reducing the combustion of fossil fuels, which emit substantial amounts of greenhouse gases. After joining the World Trade Organization, Taiwan’s agricultural sector idled about one-third of the national cropland, hereafter called “set-aside land”. This potentially provides the land base for Taiwan to develop a bioenergy industry. This dissertation examines Taiwan’s potential for bioenergy production using feedstocks grown on set-aside land and discusses the consequent effects on Taiwan’s energy security plus benefits and greenhouse gas (GHG) emissions. The Taiwan Agricultural Sector Model (TASM) was used to simulate different agricultural policies related to bioenergy production. To do this simulation the TASM model was extended to include additional bioenergy production possibilities and GHG accounting. We find that Taiwan’s bioenergy production portfolio depends on prices of ethanol, electricity and GHG. When GHG prices go up, ethanol production decreases and electricity production increases because of the relatively stronger GHG offset power of biopower. Results from this pyrolysis study are then incorporated into the TASM model. Biochar from pyrolysis can be used in two ways: burn it or use it as a soil amendment. Considering both of these different uses of biochar, we examine bioenergy production and GHG offset to see to what extent Taiwan gets energy security benefits from the pyrolysis technology and how it contributes to climate change mitigation. Furthermore, by examining ethanol, electricity and pyrolysis together in the same framework, we are able to see how they affect each other under different GHG prices, coal prices and ethanol prices. Results show that ethanol is driven out by pyrolysis-based electricity when GHG price is high. We also find that when biochar is hauled back to the rice fields, GHG emission reduction is higher than that when biochar is burned for electricity; however, national electricity production is consequently higher when biochar is burned.

Biochar incorporation in soils has the potential to remove carbon from the atmosphere and to improve soil quality. This research focused on evaluation of the benefit of biochar incorporation in an Arizona soil. Different concentrations of biochar (charcoal from mesquite biomass-derived black carbon) were added to soil in greenhouse experiments. Seven common or potential Southern Arizona crops (alfalfa, wheat, cotton, grain and sweet sorghum, barley and switch grass) were evaluated in the greenhouse experiment. In this experiment; increased biochar concentration treatments produced greater height and biomass production in alfalfa. Sorghum biomass production also increased with biochar concentration. There were no significant differences in biomass production in wheat and barley with increased biochar concentration. Switch grass biomass production had a significant negative correlation with increased biochar concentration. Sweet sorghum biomass production was evaluated in a field experiment conducted at the University of Arizona Red Rock Agricultural Center. A relatively small amount of biochar was incorporated in the top 20 cm of soil in one treatment and soil only was the other treatment: there were no significant differences in yield.Water characteristic curves and bulk densities were measured for biochar/soil mixes. The FASE model was used to simulate evapotranspiration and crop yield for the field sorghum experiment and for several crops grown in the Valsequillo Irrigation District, Puebla, Mexico with measured soil parameters. The model predicted no significant increase in sorghum yield for the level of biochar incorporated in the soil. An increase in yield was predicted for Valsequillo crops.

Some areas near Flin Flon, MB and Creighton, SK are devoid of vegetation due to a variety of mining, smelting, forestry activities and forest fires that have occurred since the 1930’s. This study investigated the use of soil amendments to enhance revegetation in these areas. The study was comprised of two main components, an in situ study and a growth chamber trial. The in situ component was conducted to determine the efficacy of soil amendments that could be utilized in a revegetation program. The growth chamber trial examined if the amount of moisture present in the soil would have an influence on the success of vegetation survival and growth. The in situ study was conducted near Flin Flon, MB and Creighton, SK over two growing seasons and consisted of replicated treatments imposed at 12 sites. Tree seedlings [trembling aspen (Populus tremuloides Michx.) and jack pine (Pinus banksiana Lamb.)] and understory species [tufted hairgrass (Deschampsia cespitosa L.) and American vetch (Vicia americana Muhl.)] were planted at each site. Each site also received soil amendments; bone meal and meat biochar (BMB), compost, commercial mycorrhizal inoculant (EMF) and, willow biochar (WB) in combination with dolomitic limestone and fertilizer. Each site also had a control that received an application of only dolomitic limestone and fertilizer. The growth chamber trial utilized the same plant species and soil amendments as the field trial with the exclusion of willow biochar. In general, soil amendments did not influence the survival or growth of the tree seedlings in situ or in the growth chamber trial. However, the compost amendment increased survival and growth of the tufted hairgrass significantly in the growth chamber trial and to a lesser extent in the field trial. Compost also positively influenced the pH and base saturation of the soil compared to the other amendments. The mycorrhizal inoculant increased the rate of mortality of tree species in the growth chamber trial. Moisture did not influence the survival and growth of the seedlings or understory species or the efficacy of the amendment treatments in this study.

Loss of soil organic carbon (SOC) resulting from intensive agriculture practices has impacts on both climate change, through emissions of greenhouse gases, as well as food security because of declines in soil fertility. A possible solution for rapidly restoring and stabilizing SOC is through additions of biochar to soil. Biochar is a carbon-rich material formed by pyrolysis (heating) of biomass in an oxygen-limited environment. A biofuel company, ABRI-Tech, has proposed an economically feasible method of using biochar in Canadian agriculture that involves enriching biochar with urea ammonium nitrate (UAN) fertilizer and applying small amounts (~1 t/ha) of biochar annually. The main objectives of this study were to evaluate the ability of biochar-UAN (Char+) to increase agricultural productivity and SOC in temperate regions. This study presents the results of a growth chamber experiment, two field trials and Century Soil Organic Matter modeling. In the growth chamber experiment, Char+ significantly increased the shoot dry mass (DM) of maize (Zea mays) by 310% in sandy textured soil, 112% in medium soil and no significant difference was observed in fine soil. However, in all soil textures, as well as the Char+ field trial, the maize DM resulting from 1 t/ha Char+ was not significantly different from UAN treatments. The biochar field trials demonstrated that if 1 t/ha of Char+ was applied annually the maize biomass production would not be affected after 6-12 years (6.2-12.4 t biochar/ha), and there may be slight improvement in yields of about 25% after 25 years (24.8 t biochar/ha). Although no significant differences in SOC were found in the field trial, there was a trend of increasing SOC as biochar application rates increased. The Century model predicted that annual addition of 1 or 2 t Char+/ha will increase SOC more than other management practices, including crop rotation, no-till and manure, over a 150 year period. The model predicted that applying 1 t Char+/ha per year to a sandy soil will increase SOC by 10% after 10 years and 17% after 20 years. This research is significant because it shows how an economically feasible method of using biochar can improve the sustainability of agroecosystems and increase terrestrial carbon sequestration in temperate regions.

Despite recent instability in the global supply of phosphate-rock derived fertiliser and the potential for this to continue into the future, the recovery of phosphorus (P) from wastewater treatment systems, where P is abundant and accessible, is well below maximum potential. Considerable resource is spent on removing P from wastewater in order to comply with environmental standards and to protect aquatic ecosystems from eutrophication, yet there is little emphasis on capturing the P in a way that is optimised for re-using it as agricultural fertiliser. To address this lack of innovation in the face of climate change and food insecurity, a concept for a material capable of capturing P from wastewater was developed, with an emphasis on the utilisation of otherwise waste materials and the use of carbon neutral or negative production technologies. Based on the demonstrated P capture properties of coal minewater treatment waste (ochre) and biochar made from anaerobically digested feedstocks, a range of biochars were designed and produced using different mixtures of ochre (“OC”), sourced from the UK Coal Authority Minto minewater treatment scheme in Fife, Scotland and anaerobically digested sewage sludge (“AD”), sourced from the Newbridge wastewater treatment plant in Edinburgh. A first generation of materials consisting of either AD or a 1:1 mixture (dry weight basis) of OC and AD were produced in a small-scale batch pyrolysis unit at two pyrolysis highest treatment temperatures (HTTs) (450 and 550°C) to give the biochars AD450, AD550, OCAD450 and OCAD550. These were tested for their P capture properties in repeated P-exposure experiments with pH buffering in comparison to unpyrolysed ochre, activated carbon and a natural zeolite. After 5 days of repeated exposure to a P solution at a wastewater-relevant concentration (20 mg P l-1) replenished every 24 h, relatively high masses of P were recovered by ochre (1.73 ± 8.93×10-3 mg P g-1) and the biochars OCAD550 (1.26 ± 4.66×10-3 mg P g-1), OCAD450 (1.24 ± 2.10×10-3 mg P g-1), AD450 (1.06 ± 3.84×10-3 mg P g-1), and AD550 (0.986 ± 9.31×10-3 mg P g-1). The biochar materials had higher removal rates than both activated carbon (0.884 ± 1.69×10-2 mg P g-1) and zeolite (0.130 ± 1.05×10-2 mg P g-1). To assess the extractability of recovered P and thus potential plant bioavailability, P exposure was followed by repeated extraction of the materials for 4 days with pH 7-buffered deionised water. The AD biochars retained 55% of the P recovered, OCAD biochars 78% and ochre 100%. Assessment of potentially toxic element (PTE) concentrations in the biochars against guideline values indicated low risk associated with their use in the environment. A second generation of materials were produced to examine the scalability of the concept. Mixtures of AD and OC were pelletised with a lignin binder (89.1:9.9:1.0 ratio, dry weight basis) and AD was pelletised with binder (99:1 ratio, dry weight basis). The pelletised feedstocks were pyrolysed in a bench-scale continuous flow pyrolysis kiln at the same two HTTs to give the pelletised biochars PAD450, PAD550, POCAD450 and POCAD550. Analysis of digested biochar samples compared to the previous generation of biochars showed general similarities between the two groups, apart from the substantially lower Fe content. Sub-samples of the pelletised biochars were exposed to a 20 mg l-1 P solution over 6 days, with the solution replaced every 24 h to give the P-exposed biochars EPAD450, EPAD550, EPOCAD450 and EPOCAD550. To probe the mechanisms of P capture by these materials and how feedstock preparation and pyrolysis conditions affected these, spectroscopic analysis using laser-ablation (LA) ICP-MS, X-ray diffraction, X-ray photo-electron spectroscopy (XPS) and scanning electron microscopy coupled with energy dispersive X-ray was performed. The results highlighted the general importance of Fe minerals in P capture and subsidiary roles for Al, Ca and Si. A 3-week barley (Hordeum vulgare) seedling growth experiment was conducted using the pelletised and P-exposed biochars, in comparison with other biochars produced using feedstock which contained high amounts of PTEs. The biochars were also extracted using a range of different methods used to assess the bioavailability of PTEs and nutrients in soils, and the results compared to digests of barley leaves to identify whether any of these could reliably predict plant bioavailability in biochar. The above ground biomass and its total P concentration of barley grown in a 5% mixture of EPOCAD550 in sand was significantly higher than the control (p < 0.05 and p < 0.01, respectively). A significant positive correlation between mean leaf P mass and dry weight leaf yield (R2 = 0.865, p < 0.001) was found, indicating that dry weight yield could be used as an indicator for the P fertilising capability of biochar for barley seedlings. Element concentrations in unbuffered and buffered and (pH 7) 0.01 M CaCl2 biochar extractions were significantly positively correlated with plant leaf concentration for 6 of the 18 elements investigated, more than any of the other extractions. A longer barley growth experiment was conducted, using rhizoboxes, to test the bioavailability of P in the biochars compared to conventional fertiliser. The pelletised and Pexposed biochars were applied to a sandy loam soil with P constraints. Biochar application rates were based on 2% formic acid extractable P, calculated for summer barley using Index 0 soil. Analysis of total leaf length at harvest (12 weeks), dry weight yield, leaf P concentration and leaf P mass showed no significant differences between the biochar treatments, NPK fertilised and NK fertilised controls. This shows that biochar, when applied at low total application rates based on extractable P, is as effective as conventional fertiliser. Now that AD biochar materials have been shown to have useful phosphorus recycling properties in laboratory experiments, additional work is required to optimise their use in wastewater and agricultural systems. The next stage of research should determine their performance in flow-through filtration systems with simulated and real wastewater effluent, as well as their performance in field trials with different crops of interest to demonstrate their potential as viable alternative fertilisers.

Made available in DSpace on 2018-08-01T22:33:11Z (GMT). No. of bitstreams: 1 tese_9663_Ronaldo Willian da Silva.pdf: 2346348 bytes, checksum: 0792f0dd1cb8acc0cf9bf62a78801c14 (MD5) Previous issue date: 2017-02-23 / A matéria orgânica do solo (MOS) é de grande importância na formação e manutenção de propriedades químicas, físicas e biológicas dos solos tropicais e, contribui com até 80 % de sua capacidade de troca catiônica. No entanto, em regiões tropicais, a taxa de mineralização da MOS atinge altos níveis devido a altas temperaturas, umidade e a atividade microbiana, reduzindo sua quantidade nos solos. Uma alternativa para a manutenção da MOS é a utilização de biocarvão, produto da decomposição térmica de materiais orgânicos sob baixa concentração de oxigênio e em temperaturas controladas. O biocarvão é mais resistente à degradação biológica é indicado como alternativa promissora para armazenar carbono no solo por longo tempo. Além disso, sua presença no solo pode aumentar o pH, CTC, nutrientes, retenção de água, atividade biológica do solo e o rendimento das culturas. No entanto, as características e benefícios do biocarvão estão associados com a temperatura de pirólise e a matéria prima utilizada para o seu processamento. Neste sentido, com o objetivo de avaliar o potencial de biocarvões de palha de café (PC) e casca de eucalipto (CE) produzidos a 350 e 600 ºC como condicionadores do solo, realizaram-se dois experimentos de incubação em ambiente com temperatura controlada a 25 ºC. O primeiro experimento visou avaliar a influência dos biocarvões associado ao calcário, sobre o pH e cargas negativas do solo. Os tratamentos foram compostos por biocarvões produzidos a partir de PC e CE, duas temperaturas finais de pirólise 350 e 600 ºC, quatro doses de biocarvão 5, 10, 15 e 20 t ha-1, cinco doses de CaCO3 0, 0.55, 1.1, 2.2 e 3.3 t ha-1 e um tratamento adicional sem adição de biocarvão. O segundo experimento teve como objetivo avaliar os efeitos do uso dos biocarvões nas propriedades químicas do solo. Os tratamentos foram compostos por biocarvões produzidos a partir de PC e CE, duas temperaturas finais de pirólise 350 e 600 ºC, quatro doses de biocarvão 5, 10, 15 e 20 t ha-1, um tratamento adicional sem adição de biocarvão e sete épocas de avaliação 0, 7, 15, 30, 60, 90 e 120 dias após a incubação. Os resultados experimentais mostram que biocarvões de PC promovem maior elevação do pH do solo. Biocarvões produzidos a 600 ºC proporcionaram maior elevação do pH do solo em relação à biocarvões produzidos a 300 ºC. O efeito neutralizante da acidez pelos biocarvões se deu na seguinte ordem crescente: CE350; PC350; CE600 e PC600, apresentando elevação no pH do solo quando comparado ao tratamento controle de 1,26; 1,46; 1,61 e 1,71 unidades respectivamente. O pH do solo foi elevado com o aumento da dose de aplicação de biocarvão. A associação de doses de biocarvão com CaCO3 apresentou interação positiva no aumento do pH do solo. No entanto, o uso em conjunto do corretivo e o condicionador, em doses mais altas elevou o pH do solo além da faixa de pH ideal para a maioria das culturas (5,5 6,0). Biocarvões proporcionaram maior carga liquida negativa do solo. Esse efeito foi maior com o uso de biocarvões de PC, e potencializado com elevação da temperatura de pirólise para 600 °C. Os biocarvões de PC proporcionaram maiores teores de P, K, Mg e maior capacidade de troca de cátions (CTC). Os tratamentos com biocarvões de CE se destacaram pela maior concentração de Ca, em média, os teores de Ca no solo foram acrescidos em 5,9 e 19,4 % para as temperaturas de 350 e 600 ºC respectivamente comparando aos biocarvões de PC nas mesmas temperaturas. Tratamentos com biocarvões produzidos em maior temperatura de pirólise (600 ºC) apresentaram maiores valores de Ca e CTC para ambos os biocarvões e, maior concentração de K com uso do biocarvão de PC. O aumento da dose de biocarvão proporcionou maior concentração de nutrientes e CTC independente do material de origem e temperatura de pirólise. Já o aumento do tempo de incubação causou redução, para todos os tratamentos, nas concentrações de nutrientes, exceto o Ca e CTC do solo. PALAVRAS-CHAVE: biochar, pirólise, acidez do solo, fertilidade do solo

Belowground competition presents a threat to the production and sustainability of tree-grass ecosystems. Management scenarios designed to optimize the spatial and temporal distribution of soil resources will improve resource-use efficiency and promote greater co-production. We conducted three experiments to assess competition dynamics between loblolly pine and switchgrass. In a three-year field trial, loblolly pine and switchgrass were intercropped across varying competitive intensities. Interspecific competition decreased loblolly pine annual growth; however, establishing vegetation exclusion zones surrounding pines largely mitigated these effects. Switchgrass yields were less affected by interspecific competition compared to pines and land equivalency ratios indicated that with proper management co-production yields may exceed those of switchgrass monoculture. Switchgrass was a constant and significant competitor across all years while loblolly pine resource use was minimal in year 1 but increased in subsequent years. In a short-term greenhouse experiment, native soil was amended with biochar and inorganic N fertilizer and the effects of these amendments upon soil properties and switchgrass productivity were assessed. Biochar increased soil pH, total soil carbon, and soil moisture. However, N fertilization had negligible effects upon soil properties. Plant response to biochar was neutral to negative while N fertilization increased switchgrass foliar biomass but no interactive effects of the amendments were observed. Although the effects of biochar upon switchgrass production were trivial, its positive influence upon soil properties suggests a potential for mitigating competitive interactions. Finally, a field-scale study examined co-production of loblolly pine and switchgrass over two years in response to competition control, biochar, and N fertilizer. As expected, interspecific competition reduced soil resources and decreased plant productivity. Biochar increased total soil C and soil moisture levels but had relatively minor impacts upon other aspects of soil fertility or plant production. Nitrogen fertilization acidified soil pH and decreased total soil C and N but positively affected loblolly pine foliar N concentrations and switchgrass yields. A positive association between soil inorganic N and switchgrass yield suggests the species competitive influence may be increased with greater N supply.

Stockholm Exergi provide district heating in Stockholm and plan to integrate their district heating system with the production of biochar, by building a plant that produces 100MW district heating and 100 000 tonnes biochar per year, in order to reduce greenhouse gas emissions. Biochar may mitigate climate change, but the added benefits of biochar, beyond the benefits of carbon sequestration, lack quantification. This report aims to review, quantify and document the cumulative benefits, with respect to climate, health, and resource consumption, of biochar application to Swedish agriculture, as a livestock feed additive. A life cycle of biochar as a livestock feed additive is illustrated, where the biochar is ingested by livestock and retrieved in manure. The manure is thereafter co-composted with the biochar, and finally, returned to soil. Each step proceeding the initial application carries important benefits to climate, health or resource consumption. Providing all livestock in Sweden with biochar requires 100 000 tonnes per year and may potentially reduce greenhouse gas emissions from livestock by up to 450 000 tonnes of carbon dioxide equivalents (CO2-e) per year. Distributing the biochar to farms across Sweden results in around 10 000 tonnes of CO2-e emissions per year. Hence, the potential net annual reduction in greenhouse gas emissions is approximately 440 000 tonnes of CO2-e in Sweden. This is equivalent to -590g CO2-e/kWh for a biochar plant that produces 100MW district heating. Research also suggests a reduction in greenhouse gas emissions from biochar co-composting and biochar soil application. However, the concentration of biochar retained in manure subsequent to feeding is too low to draw a conclusion regarding its effect on emissions. Health benefits of biochar as a livestock feed additive include reduced (or even eliminated) need for antibiotics, fewer cases of illness amongst livestock, fewer deaths, and higher quality cow milk. The biochar also eliminates manure odour, improving work environment for farmers. Biochar co-composting may reduce ammonia emissions and improves nutrient retention. Applying the co-compost to soils eliminates soil pathogens, detoxifies allelochemicals, increases the growth rate of beneficial microbes, and reduces fertilizer need. Crops will thus become more resistant to mould and biotic stresses. / Stockholm Exergi producerar och levererar fjärrvärme till Stockholmsregionen och planerar att bygga en anläggning som producerar 100 MW fjärrrvärme i samband med 100 000 ton biokol per år, för att minska koldioxidutsläppen. Biokol framställs genom pyrolys av biomassa och binder fast kolatomer i sin struktur, vilket leder till minskade koldioxidutsläpp om biokolet hindras från att oxideras genom någon form av lagring. Denna rapport undersöker genom en litteraturstudie de adderade nyttorna med biokol som råvara i djurfoder med avseende på klimat, hälsa och resursanvändning. De adderade nyttorna uppskattades genom att följa biokolets livscykel från råvara i djurfoder till gödsel. I första steget intas biokolet av djur, sedan hamnar biokolet i djurens avföring som därefter komposteras och används i växtodling. Det totala biokolbehovet för att mata alla produktionsdjur i Sverige uppskattades till 100 000 ton per år och beräknades minska växthusgasutsläppen med 450 000 ton koldioxidekvivalenter (CO2-e) per år. Dock måste biokolet transporteras långa sträckor över hela landet och utsläpp från transporter uppskattades till 10 000 ton CO2-e. Detta innebär en utsläppsminskning med 440 000 ton CO2-e per år, vilket motsvarar -590 g CO2-e/kWh för en biokolanläggning som producerar 100 MW fjärrvärme. Resultaten visade också att biokol förbättrar djurens allmänna hälsa, minskar dödligheten samt leder till ett minskat behov av antibiotika. Dessutom minskar lukten från gödsel, vilket förbättrar arbetsmiljön inom jordbruk. Vid kompostering kan biokol minska utsläpp av ammoniak (en giftig kemikalie) och öka koncentrationen av näringsämnen i gödseln. När det sedan används vid odling kan det leda till en ökad tillväxt av nyttiga mikroorganismer, samtidigt som patogener elimineras, vilket leder till att växter får en ökad resistans mot biotisk stress och mögel. Dessutom minskar behovet av konstgödsel.

Intensive tillage practices in the Mississippi Delta degrade soil health, impacting downstream water quality. To address this, two experiments were conducted from 2019 to 2021 and 2020 to 2022 to evaluate the impact of sugarcane biochar and flue gas desulfurization (FGD) gypsum on nutrient leaching losses and soil properties in cotton and soybean cropping systems. Study I applied four biochar rates (0, 10, 20, and 40 Mg ha-1) to cotton and found improvements in soil properties and subsurface quality, with reduced nutrient leaching losses, except for sulfate and sodium ions. Study II evaluated biochar (10 and 25 Mg ha-1) and FGD gypsum (2.24 and 6.72 Mg ha-1) application rates in soybean, resulting in reduced nitrate leaching losses and soil property improvements, mostly observed in the second year. These findings suggest that reevaluating management practices with biochar and gypsum can improve soil health and water quality, but may require a lag time to realize benefits.

Providing safe drinking water and wastewater remediation are constant worldwide challenges. Adsorption is an attractive alternative to conventional techniques such as coagulation, precipitation (chemically or electrochemically), hybrid membranes, and ion-exchange for the purification of water. Biochar-based composite sorbents are increasingly popular because a range of surface chemical and physical treatments can impart performance and environmental benefits to the material. This is ideal for rural areas where more costly conventional methods may not be readily available or affordable. This dissertation focused on three different projects involving high surface area (~700 m2/g) Douglas fir biochar based multifunctional engineered adsorbents. Chapter II focuses on arsenic (III) adsorptive removal onto magnetic iron oxide dispersed onto biochar. This chapter highlights the adsorptive and redox properties of biochar composites for pollutant toxicity reduction. Chapter III focuses on pollutant toxicity neutralization after adsorption, simultaneous adsorption, and multi-phase adsorption. A MIL-53-MOF magnetite/magnetic biochar composite model system was used to demonstrate simultaneous chromium (VI) adsorption and organic pollutant rhodamine (RhB) degradation. Chapter IV is focused on tailoring the biochar to change its physical properties (enhance hydrophobicity) to achieve a specific pollutant treatment requirement (buoyancy). Oil spill remediation was used as a model example for this purpose and lauric acid-decorated magnetite biochar composite was introduced. The composites and their pollutant-loaded analogues were extensively characterized using BET, SEM, TEM, EDS, XRD, VSM, PZC, Elemental analysis, TGA, DSC, FT-IR and XPS.