The wide use and the incomplete metabolism of antibiotics, along with the poor removal efficiency of current treatment systems, results in the introduction of large quantities of antibiotics to the environment through the discharge of treated and untreated wastewater. If not treated or attenuated near the source of discharge, the antibiotics can be distributed widely in the environment. In this research, sulfamethoxazole (SMX), a common sulfonamide antibiotic, was selected as a model compound due to its presence in the environment and its resistance to remediation and natural attenuation. Among the various entry routes, discharges from on-site disposal systems are of particular interest due to the wide use of these systems. The complex nature of subsurface transport downstream of these systems adds difficulties to the removal of SMX from subsurface discharges. For this research, two processes that impact SMX removal, biodegradation and sorption, were examined to determine the primary factors governing the elimination of SMX from septic effluent discharges in the subsurface. To characterize the biodegradation of SMX, batch experiments were conducted with SMX in the presence of septic effluent and soil for both aerobic and anoxic conditions. Results showed that SMX removal was limited in the septic effluent but increased in the presence of soil, demonstrating the important role of the soil in SMX removal in both aerobic and anoxic conditions. Addition of external nutrients (ammonium and sulfate) had small effects on SMX removal, although SMX removal was enhanced under aerobic condition with increased dissolved organic carbon. To overcome the limited sorption of SMX on soil, soil amendments were developed and evaluated using biochar, a green and cost-effective adsorbent. Biochars produced from different types of feedstock were characterized for different pyrolysis temperatures, and their adsorption behaviors were examined and compared with commercial biochar and activated carbon (AC). Adsorption isotherms were developed and adsorption kinetics of soil, biochar and AC were studied. Results showed that adsorption on soil, biochar and AC followed three different kinetics models and their equilibrium isotherms followed the Freunlich model. Higher adsorption rates were achieved with biochars prepared at the higher temperature. A lab-engineered biochar with pine sawdust at 500 °C achieved comparable sorption capacity to AC. SMX transport in subsurface was also explored with saturated soil columns filled with soil that was mixed with biochar at different percentages. Significant SMX removal (including complete elimination at a low flowrate and over 90 % elimination at a high flowrate) for all cases was primarily attributed to biodegradation. These results provide insight into the transport and transformations affecting SMX, and then provide a basis for developing low-cost approaches for the mitigation of SMX.

Maintaining an adequate level of soil organic matter and nutrients cycling is crucial to the success of any soil management in the humid tropics. Cover crops, compost, or manure additions have been used successfully to supply nutrients to crops but the benefits of such amendments are often short-lived in the tropics, since decomposition rates are high. This study focused on charcoal which, when utilised as a soil amendment is termed ‘biochar’. Throughout this thesis, the terms ‘charcoal’ and ‘biochar’ are used interchangeably depending on the context. Charcoal exhibits physiochemical properties potentially suitable for soil improvement as well as for the safe and long-term storage of carbon in the environment. As a way of investigating its recalcitrance as a carbon store, O:C ratios have been shown to reflect the extent of oxidation and therefore decomposition of charcoal. This study aimed to fill a gap in the research by describing the effects of biochar on the water retention capacity of soil under laboratory conditions. It also provides a detailed snapshot of the first ten years of recalcitrance under natural conditions, using X-Ray Photoelectron Spectroscopy (XPS) to determine elemental oxygen and carbon ratios of whole charcoal fragments and how these are affected by the surrounding environment over time. Mechanisms of oxidation are described, showing how both biotic and abiotic factors influence the degradation of charcoal in the soil. It also investigated how these properties affect the nutrient and water retention capability of charcoals of different ages in the laboratory. Results of charcoal/soil mixtures showed significant reduction in nitrate leachate losses with no reduction in performance over a ten year period of residing in the soil. It was also shown that charcoal addition to a sandy soil resulted in a significantly increased available water content. Both these results were argued to support the idea that charcoal is of potential beneficial amendment to sandy, degraded soils.

Biochar has been heralded as a promising technology for climate change mitigation that can also benefit soils. Biochar is a carbonaceous solid produced by pyrolysis of biomass – the thermal decomposition of plant and plant-derived matter in the absence of oxygen. When added to soils, biochar has the potential to increase crop yields and suppress soil emissions of greenhouse gases, whilst sequestering carbon in a stable form. In addition to biochar, biomass pyrolysis produces liquids and gases that can serve as biofuels. Biochar production systems that generate excess heat or power are particularly environmentally and economically attractive. Rotary kilns are the favoured process reactor in many industries, given their potential to handle a wide range of feedstocks and provide good process control. This thesis investigates the potential to coproduce biochar and excess biofuels by slow pyrolysis in a pilot-scale rotary kiln. The work attempts to progress towards the ultimate aim of scaling up the rotary kiln and optimising its operating conditions to produce biochar of good quality along with an excess of useful biofuels. Experimental work, involving the development and application of new methodologies, was used to gain a better understanding of the process. The data gathered were then used to support preliminary numerical simulation efforts towards the development of a comprehensive process model. Five biomass feedstocks were considered: softwood pellets, miscanthus straw pellets, wheat straw pellets, oilseed rape straw pellets and raw rice husks. The granular flow of biomass feedstocks was observed in a short closed drum faced with acrylic and resting on rollers. All pelletized feedstocks displayed similar angles of repose, validating the use of softwood pellets as a model biomass for these feedstocks. Bed mixing, which can improve product uniformity, was slow under typical operating conditions, requiring 5 min to complete at 4 rpm for softwood pellets. Mixing quickened considerably at higher rotation rates. A digital image analysis method was developed to measure the distribution of solid residence times inside the rotary kiln. The mean residence time of softwood pellets ranged from 19 to 37 min under typical operating conditions, decreasing with increases in kiln rotation rate, but mostly unaffected by feeding rates. These findings show that kiln rotation rates must be selected to balance the residence time of solids inside the kiln with bed mixing levels. Thermogravimetry and differential scanning calorimetry were performed on samples of ground softwood pellets under five different heating profiles to study the kinetics and heat flows of the pyrolysis process. Both exothermic and endothermic regions were identified, with most reactions taking place between 250°C and 500°C. Results suggest that exothermic pyrolysis reactions can be promoted by altering the process heating rate, thereby improving net biofuel yield from the process. The thermogravimetric data collected was used to develop a distributed activation energy model (DAEM) of the kinetics of softwood pellet pyrolysis for integration into a comprehensive model of the process. The applicability of the kinetic model to large-scale processes was confirmed using a simplified process model developed to simulate biomass pyrolysis inside the pilot-scale rotary kiln. Although crude, the simplified process model produced sufficiently accurate estimates of char yield for preliminary design purposes. The simplified model also allowed important process parameters, such as kiln filling degree, solid residence time and heating rate, to be evaluated. A series of pyrolysis experiments was performed on the pilot-scale rotary kiln to evaluate the yields of biochar and biofuels and determine the temperature profile inside the kiln. This work required the design of a suspended thermocouple system that measures temperatures along the kiln, both in the gas phase and inside the solid bed. For most experiments at 550°C, a region of high temperature gas and solids was observed, possibly indicative of exothermic reactions. Biochar yield varied from 18% to 73% over the range of feedstocks and operating conditions tested. A vapour sampling methodology that relies on the use of a tracer gas was developed to determine the yield of pyrolysis liquids and gases. Due to analytical difficulties, it was not possible to obtain accurate mass closure with this method. However, the methodology revealed significant air ingress into the pilot-scale rotary kiln that is responsible for partially combusting biofuels produced by the process, thereby reducing their calorific value. Energy balances on the kiln confirmed that the calorific content of pyrolysis liquids and gases exceeds the energetic demand of the process, yielding between 0.3 and 11 MJ in excess biofuels per kg of biomass feedstock. An attempt was made to develop a multiphase model of the flow of vapours and solids inside the rotary kiln using computational fluid dynamics (CFD), but the continuous modelling approach was found inadequate to simulate the dense bed of biomass inside the kiln. The discrete element method (DEM) was sought as an alternative to model the granular flow of biomass inside the kiln. Extensive parameter calibration was required to reproduce the experimental behaviour of softwood pellets observed in the short closed drum. A model of the pilot-scale rotary kiln was constructed to simulate particle residence times. Further parameter calibration was required to replicate softwood pellet holdup inside the kiln. The calibrated model was able to reproduce the mean residence time of softwood pellets within 10% under different kiln operating conditions. However, simulated residence time distributions could not be established as a result of the long execution times required for this modelling work. Few data are currently available on large-scale continuous biomass pyrolysis processes; the experimental data gathered in this thesis help to fill this gap. Along with the numerical simulation work presented herein, they provide the foundation for the development of a comprehensive model of biomass pyrolysis in rotary kilns. Such a numerical model would prove invaluable in scaling up the process and maximizing its efficiency. Future work should consider the agronomic value and carbon sequestration potential of biochar produced under different operating conditions. In addition, the performance and efficiency of different conversion technologies for generating heat and power from biofuels need to be investigated.

Submitted by RISELY FERRAZ ALMEIDA (rizely@gmail.com) on 2017-03-22T01:11:45Z No. of bitstreams: 1 Tese_Risely_Ferraz_Almeida.pdf: 1907638 bytes, checksum: 54826ce5c26a680dbbfdb607f7d4cad5 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-03-22T20:23:04Z (GMT) No. of bitstreams: 1 almeida_rf_dr_jabo.pdf: 1907638 bytes, checksum: 54826ce5c26a680dbbfdb607f7d4cad5 (MD5) / Made available in DSpace on 2017-03-22T20:23:04Z (GMT). No. of bitstreams: 1 almeida_rf_dr_jabo.pdf: 1907638 bytes, checksum: 54826ce5c26a680dbbfdb607f7d4cad5 (MD5) Previous issue date: 2017-02-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O oxigênio (O2) e o dióxido de carbono (CO2) no solo são os dois principais gases relacionados com a atividade dos microorganismos no solo. Assim, esta tese foi desenvolvida para observar a concentração e a relação entre a concentração do CO2 e O2 sob diferentes sistemas de resíduos. Para isso, realizamos dois experimentos de solo no Brasil e nos EUA, respectivamente. O primeiro experimento foi desenvolvido para examinar a relação entre fluxo de CO2 (FCO2) e o fluxo de O2 (FO2) usando a umidade do solo e o O2 como um predictor da respiração do solo em uma área de cana-de-açúcar sob diferentes manejos de resíduos (colheita mecânica - GH versus colheita queimada – BH). Portanto, os resultados do primeiro experimento estão descritos no Capítulo 2 e sendo intitulado de "Uso da captura de O2 como índice de respiração de CO2 em áreas de cana-de-açúcar sob diferentes manejos". O segundo experimento do solo observou o impacto do biochar na emissão ou sorção de CO2 e O2 nos solos. Assim, foram estudados três tipos de solos (Rosemount - RM, Potting Sol Sunshine - PS e UM), cinco biochars diferentes (biochar de chip de pinho - ICM, biochar de Carvalho Oak Royal - RO, biochar Acurel ativado - AAC, biochar de Bambu - B; biochar de Macadâmia - MC) e o tratamento controle (solo sem biochar). Consequentemente, os resultados foram descritos no Capítulo 3 e intitulado "Como a captura de O2 pode nos ajudar a entender os processos de sorção de CO2 via biochar?". Assim, nós podemos concluir com os nossos resultados que a concentração e relação entre FCO2 e FO2 dependem dos diferentes sistemas e condições dos solos estudados, tais como: manejo de resíduos de culturas do solo, umidade do solo e uso de biochar. O FO2 está positivamente correlacionado com o FCO2 via atividade biológica e com valores de coeficientes respiratório (RQ) próximos de 1,0. Além disso, podemos observar que valores de RQ maiores que 1 são resultados dos fluxos de troca solo-gás após precipitação ou maior disponibilidade de O2 no meio. Assim, o FO2 pode ser utilizado como um índice para categorizar uma fonte de respiração de CO2. Para concluir, o biochar pode ser utilizado para sequestrar CO2 da atmosfera em curto período de tempo. No entanto, acreditamos que mais estudos devem ser desenvolvidos para elucidar a sorção de CO2 e O2 pelo biochar e suas reações (biológicas e/ou químicas) quando adicionado biochar no solo. / The soil O2 and CO2 concentration are the two most important gases related to soil microorganisms. Thus, this thesis was developed to observe the concentration and relationship between carbon dioxide (CO2) and oxygen (O2) under different residue systems. For that, we run two soil experiments in Brazil and the USA, respectively. The first experiment was developed to examine the relationship between CO2 and O2 using soil moisture and O2 as a soil respiration predictor in a sugarcane area under different managements of residues (mechanical harvesting - GH versus straw burning - BH). Therefore, the first experimental results are described in the Chapter 2 and entitled “Use of O2 uptake as an index of CO2 respiration in sugarcane areas under different managements”. We run the second soil experiment measuring biochar’s impact on CO2 production or sorption and O2 uptake in amended soils. Thus, we studied three soil types (Rosemount - RM; Potting soil Sunshine - PS; and UM) and five different biochars (Pine chip biochar - ICM; Royal Oak hardwood lump charcoal - RO; Accurel activated charcoal - AAC; Bamboo - B; and Macadamia nut - MC) and control treatment (Soil without biochar). Consequently, the results are described in the Chapter 3 and entitled “How O2 uptake can help us understand the CO2 sorption processes by biochar?”. Thus, we can conclude with our results that the concentration and relationship between FCO2 and FO2 depend on different systems and soil conditions, for example: soil crop residue managements, soil moisture and use of biochar. The FO2 is positively correlated with FCO2 at biological condition with respiratory quotient (RQ) values close to 1.0. Moreover, we can observe that RQ values higher than 1 are results of soil–gas exchange fluxes after precipitation or higher available on O2. Thus, the FO2 can be used as an index for categorizing the source of FCO2 respiration. To finish, we can observe that the biochar can be used to sequester CO2 from the atmosphere by the absence of biological activities in a short period of time. However, we believe that more study should be developed to elucidate the CO2 and O2 sorption by biochars and their reactions (biological and/or chemical) when added biochar in soil.

From an agronomic perspective, the spreading of manure (sometimes containing antibiotics) onto agricultural fields is beneficial to the soil as a renewable source of fertilizer by increasing organic matter and providing nutrient inputs for crops. However, the use of antibiotics can be excessive, resulting in manures containing residual antibiotics contaminating soils and waterways. Thus, there is a need to improve existing or develop new management practices to minimize the losses of antibiotics from manure entering waterways and groundwater. Biochar is a carbon-rich material produced from the oxygen-free pyrolysis of biomass. Generally, biochars have high surface area and sorb organic compounds and trace metals; thus, it is reasonable to hypothesize that biochars sorb antibiotics. The main goal of this research was to investigate if incorporated biochar to soil facilitates the transport of antibiotics under simulated rainstorm events. The specific objectives were to investigate the losses of surface-applied antibiotics to soils with different (1) application rates of biochar and rainfall intensities, and (2) if the losses were antibiotic type-dependent. <br>

Biochars are the product of high temperature treatment of carbonaceous materials with little or no oxygen present, termed “pyrolysis”. Biochars derived from the pyrolysis of biomass feedstocks have proven effective amendments on highly weathered tropical soils. However less is known about their impact on temperate soils and associated crop growth. Moreover, there is inadequate knowledge of the impacts of different biochars produced from different feedstocks under differing pyrolysis conditions. Therefore, a study was conducted to evaluate the effectiveness of different biochars as amendments to improve soil conditions for crop growth, with emphasis on soil fertility and crop nutrition impacts. The response of canola-wheat in rotation to five biochars was evaluated in controlled environment and field experiments conducted on Brown and Black Chernozem soils over a two-year period. Treatments were biochar added at 1 and 2 t ha 1 without and with nitrogen (N) and phosphorus (P) fertilizers at 50 or 100 kg N ha 1 and 25 kg P2O5 ha 1. Parameters evaluated were crop biomass and grain yield, N and P uptake, % recovery of applied N and P, residual soil nutrients (NO3 N, and PO4+ P), pH, electrical conductivity (EC), % organic carbon (% OC) and gravimetric soil moisture. Biochar application resulted in significant increases (p<0.05) in canola yield compared to the control for two fast pyrolysis biochars originating from wheat and flax straw added to the Black Chernozem soil in both studies. No significant response was observed for any of the biochars on the Brown Chernozem. Slow pyrolysis biochar derived from willow feedstock appeared less effective did not show any significant response. Occasional depressions in crop yield were observed in both crops with both soils. In these calcareous Chernozems, biochar did not greatly alter the N and P availability, and its effects on soil pH, % OC, EC and moisture content were small and often non-significant. These results suggest that biochar applications at 1 2 t ha 1 to prairie Chernozemic soils will not have large effects on soil properties or plant growth. Higher rates of application will require development of application technology due to the dusty, powdery nature of the biochar material.

Pyrolys innebär att exempelvis biobränsle hettas upp i syrefattig miljö för att bilda pyrolysgas och kol. Pyrolysgasen kan brännas för att producera värme med låga utsläpp och kolet har en mängd användningsområden; jordförbättringsmedel, fodertillskott, filtermaterial, kolfastläggning, energibärare, ståltillverkning m.m. Om krav på bränsle och användningsområde för kolet uppfylls kan kolet certifieras som biokol. Syftet med den här rapporten är att utreda om pyrolystekniken är ett hållbart, tekniskt och ekonomiskt alternativ till pellets- och flisförbränning för värmeproduktion. Målet är att förmedla pyrolysens tekniska och ekonomiska förutsättningar, såväl positiva som negativa. Rapporten är baserad på en kombination av litteraturstudier, djupintervjuer, besök vid anläggningar och referensgruppsamtal.   Pyrolys har använts i tusentals år för att producera kol. I Amazonas upptäcktes landområden med en sammalagd yta större än Storbritannien i vilka jorden var kolsvart. Denna svarta jord, terra preta, är berikad med kol och har därmed blivit mycket bördigare än omgivande, ursprunglig jord. I Sverige framställdes kol för att tillgodose metallindustrin med bland annat produktionsmaterial och bränsle. Till skillnad från pellets- och flisförbränning kan pyrolystekniken använda en stor mängd olika bränslen så länge de uppfyller krav på energidensitet och fukthalt. Marknaden för biokol växer i bl.a. Tyskland men är ännu liten i Sverige. De leverantörer av pyrolysanläggningar som besökts i denna rapport, Pyreg och Carbon Terra, gör anläggningar med syfte att producera biokol. Pyreg har utvecklat en process med skruvreaktor och integrerad pyrolysgasbrännare för att t.o.m. kunna använda avloppsslam som bränsle. Carbon Terras process är enkel och robust med fokus att producera mycket kol.   Pyrolysteknikens styrkor är flexibiliteten att välja olika typer av bränslen, låga utsläpp, liten negativ miljöpåverkan och kolets olika användningsområden. Ser man till svagheterna är de marknadsrelaterade; outvecklad svensk marknad och okunskap om kolets användningsområden. Dessutom gör pyrolysanläggningarnas statiska effektuttag att de är mindre flexibla än pellets- och flispannor. I en tid då klimatförändringarna letar akuta lösningar medför kolfastläggning och biokol som jordförbättringsmedel stora möjligheter tillsammans med omvandling av pyrolysgas till fordonsbränsle. Dock är den befintliga pellets- och flisförbränningen väletablerad som uppvärmningsteknik, vilket kan utgöra ett hot mot pyrolysteknikens intåg på marknaden. Avsaknaden av regelverk pga. kompetensbrist kan också försvåra för etablering av pyrolysanläggningar.   Slutsatsen i denna rapport är att pyrolystekniken är ett bra alternativ till konventionell pellets- och flisförbränning om man kan hantera att värmeproduktinen är statisk och att man beaktar kolets värde. Värmeproduktion från pyrolysgas ger lägre utsläpp av bland annat CO, NOx och stoftpartiklar än pellets- och flisförbränning och om kolet används för kolfastläggning är möjligheten till globala klimateffekter betydande. Det som starkast påverkar den ekonomiska kalkylen är kostnaden för bränslet och intäkten på kolet. För att gardera sig mot den outvecklade biokolmarkanden i Sverige har kalkylerna i denna rapport baserats på försäljning av biokol som jordförbättringsmedel, vilket ger låga intäkter jämfört med andra användningsområden. Styrkan i att valet av bränsle är flexibelt gör det möjligt att ha en bränslekostnad på noll om materialet annars ses som avfall. Marknaden för kol i Sverige är outvecklad vilket kräver ett aktivt arbete från de som ger sig in branschen, men om utvecklingen följer den i Tyskland ser de ekonomiska förutsättningarna starka ut. / Pyrolysis is the process where biomass is heated in an environment with low oxygen level forming pyrolysis gas and char. Pyrolysis gas can be combusted to produce heat with low emissions and the char has a multitude of uses: soil improvement, animal feed supplements, filter material, carbon storage, energy source, steel production etc. If certain requirements for the fuel and how the char is used the char certified as biochar. The purpose of this report is to determine if the pyrolysis technology is a sustainable, technical and economical alternative to pellet and wood chip combustion for heat production. The goal is to convey pyrolysis technical and economic conditions, both positive and negative. The report is based on a combination of literature reviews, interviews, plant visits and reference group discussions.   Pyrolysis has been used for thousands of years to produce char. Areas, of a total area larger than the Great Britain, with pitch black soils were discovered in the Amazon. This black soil, terra preta, is enriched with carbon, and has thus become much more fertile than the surrounding native soil. In Sweden char was produced to meet the metal industries’ demand for char as material and fuel. Unlike pellet and wood chip combustion, pyrolysis can use a variety of fuels, as long as they meet the requirements of calorific value and moisture content. The market for biochar is growing particularly in Germany but is still small in Sweden. The suppliers of pyrolysis plants visited in this report, Pyreg and Carbon Terra, develop their plants in order to produce biochar. Pyreg has developed a process with a screw reactor and an integrated pyrolysis gas combustor to be able to use sewage sludge as fuel. Carbon Terra’s process is simple and robust, with a focus to produce large quantities of carbon.   The strengths of the pyrolysis technique are the flexibility to use different types of fuels, low emission, low environmental impact and the different uses of the char. Looking at weaknesses, they are market-related; undeveloped Swedish market and lack of knowledge of how to use biochar. In addition, the pyrolysis facilities have static power output that they are less flexible than pellets and wood chip combustors. At a time when finding solutions on climate change are urgent, carbon storage, using biochar as a soil improver and conversion of pyrolysis gas as a vehicle fuel are great opportunities. However, the existing pellet and wood chip combustion is well established as a heating technology, which could pose a threat to the pyrolysis technology entering the market. The lack of regulation due to shortages of knowledge of pyrolysis may also prevent the establishment of pyrolysis plants. The conclusion of this report is that pyrolysis is a good alternative to conventional pellet and wood chip combustion if you can manage the static power output and that you realize the value of the char. Heat production from pyrolysis produce lower emissions including CO, NOx and smog particles than pellets and wood chip combustion and biochar used for carbon storage has the possibility of significant global climate impact. The strongest influences on the economic calculation are the cost of fuel and the revenue of the char. The strength of being able to choose different types of fuel makes it possible to have a fuel at zero cost if the material is otherwise regarded as waste. The market for biochar in Sweden is undeveloped which increases the uncertainty of the calculations, but if the trend follows that of Germany, the economic prospects are strong.

Cotton gins have a readily available supply of biomass that is a by-product of cotton ginning. A 40 bph - cotton gin processing stripped cotton must manage 2,600 to 20,000 tonnes of cotton gin trash (CGT) annually. CGT contains approximately 16.3 MJ/kg (7000 Btu/lb.). CGT has the potential to serve as a renewable energy source. Gasification of biomasses such as CGT can offer processing facilities the opportunity to transform their waste biomass into electricity. The gasification of CGT yields 80% synthesis gas (syngas) and 20% biochar. The concentration of biochar in the syngas needs to be reduced prior to the direct fueling of an internal combustion engine driving a generator for electricity production. It was estimated that direct fueling of an internal combustion engine with syngas to drive the generator to produce electricity would cost $1M per megawatt (MW). In contrast, a 1MW system that consists of a boiler and steam turbine would cost $2M/MW. The current provisional patent for the TAMU fluidized bed gasification (FBG) unit uses a 1D2D and 1D3D cyclone for the removal of biochar. A cyclone test stand was designed and constructed to evaluate cyclone capture efficiencies of biochar. A statistical experiment design was used to evaluate cyclone performances for varying concentrations of biochar. A total of 24 tests for the 1D2D and 36 tests for the 1D3D cyclone were conducted at ambient conditions. Average collection efficiency for the 1D2D cyclone was 96.6% and 96.9% for the 1D3D cyclone. An analysis on the cyclone’s pressure drop was performed to compare the change in pressure drop from air only passing through the cyclone and when the cyclones are loaded with biochar. The average change in pressure drop for the 1D2D cyclone was a decrease of 74%, and the average change in pressure drop for the 1D3D cyclone was a decrease of 36%. An economic feasibility study was conducted to determine the price per kWh to produce electricity for a CGT fueled internal combustion engine power plant (ICPP) and a boiler and steam turbine power plant (SPP). The simulated cotton gin is a 40 bph rated facility operating for 2,000 hours a season (200% utilization) processing stripped cotton that yields approximately 180 kg/bale (400 lbs/bale) of CGT. Revenues consist of the electricity and natural gas expenses incurred during the ginning season, along with the extra electricity produced and sold back to the utility company at the whole price. Loan payments and operating costs include labor, maintenance, taxes, and insurance. Labor costs, the selling price of electricity and biochar are varied in the economic model. The ICPP has a NPV of $1,480,000, and the SPP has a NPV of -$160,000, under the base assumptions. The sensitivity analysis resulted in the selling price of electricity as having the largest change on the NPV for both of the power plants. The average predicted purchase price of electricity is $0.10/kWh for the twenty year simulation. The average price to produce electricity, with no source of revenue generation for the ICPP is $0.20/kWh and $0.26/kWh for the SPP.

abstract: Haiti has witnessed high deforestation rates in recent decades, caused largely by the fuel needs of a growing population. The resulting soil loss is estimated to have contributed towards a decline in agricultural productivity of 0.5% -1.2% per year since 1997. Recent studies show the potential of biochar use through pyrolysis technology to increase crop yields and improve soil health. However, the appropriateness of this technology in the context of Haiti remains unexplored. The three objectives of this research were to identify agricultural- and fuel-use-related needs and gaps in rural Haitian communities; determine the appropriateness of biochar pyrolyzer technology, used to convert agricultural biomass into a carbon-rich charcoal; and develop an action-oriented plan for use by development organizations, communities, and governmental institutions to increase the likelihood of adoption. Data were collected using participatory rural appraisal techniques involving 30 individual interviews and three focus-group discussions in the villages of Cinquantin and La Boule in the La Coupe region of central Haiti. Topics discussed include agricultural practices and assets, fuel use and needs, technology use and adoption, and social management practices. The Sustainable Livelihoods framework was used to examine the assets of households and the livelihood strategies being employed. Individual and focus group interviews were analyzed to identify specific needs and gaps. E.M. Rogers' Diffusion of Innovations theory was used to develop potential strategies for the introduction of pyrolysis technology. Preliminary results indicate biochar pyrolysis has potential to address agricultural and fuel needs in rural Haiti. Probable early adopters of biochar technology include households that have adopted new agricultural techniques in the past, and those with livestock. Education about biochar, and a variety of pyrolysis technology options from which villagers may select, are important factors in successful adoption of biochar use. A grain mill as an example in one of the study villages provides a model of ownership and use of pyrolysis technology that may increase its likelihood of successful adoption. Additionally, women represent a group that may be well suited to control a new local biochar enterprise, potentially benefiting the community. / Dissertation/Thesis / M.S. Sustainability 2011

This thesis deals with the influence of biochar on saturated hydraulic conductivity (Ks) of contaminated fluvisol. Values of Ks are key inputs for modeling of water flow in soils. Contaminated fluvisol and this soil enriched by 2 and also 5% of biochar were studied in this thesis. These differently treated soils ware gauged to find out differences in Ks and changes of Ks time. Biochar improves sorption capacity and other soil properties. The influence of biochar application on Ks it not fully revealed. We used biochar which was made by pyrolysis of stalks of grapevine. Measurements were made in two series since October to December in 2015. For both series, 10 samples, (5 in reference and 5 enriched by biochar) were measured. A total of 20 samples were measured in each series. Every sample was measured for 14 days in 10 time steps (10 recurrent measurements). Physical properties (bulk density, porosity, saturated water content) and particle size analysis using hydrometer method were also measured. Homogeneous soil mixtures of the soils were packed in Kopeckého sampling rings (100 cm3). In first series, 5 reference samples and 5 samples with 2% content of biochar were compared. Saturation of the samples was made gradually and slowly and takes 1 week. Measurement was made by laboratory permeameter (hydraulic gradient about 0.5). For reference samples of first series, mean Ks value was 4,818.10-6 m.s-1. For samples enriched by 5% biochar mean Ks value was 2,254.10-6 m.s-1. For reference of second series, mean Ks value was 6,435.10-6 m.s-1. For samples enriched by 2% biochar mean Ks value was 4,211.10-6 m.s-1. Application of biochar on tested soil decrease Ks in comparison with reference soil. Decrease of Ks value was more distinct for soil enriched 5% of biochar than for soil enriched by 2% of biochar. Application of biochar also decrease coefficient of variation of measured Ks. in most of the time steps. Reference samples exhibited larger differences of Ks among time steps than biochar enriched soils.