Main Feedstock Research Articles

Growth characteristics and photofermentative biohydrogen production potential of purple non sulfur bacteria from sugar cane bagasse

Photofermentative biohydrogen production from lignocellulosic waste is a potentially favorable approach for advance biofuel. Using raw sugarcane bagasse (SCB) as the main feedstock, this study resulted in 148–513 ml H2/l produced by indigenous isolates of purple non sulfur bacteria (PNSB) in batch cultures. The maximum yield of 1.96 mol H2/moles sugar was achieved at 30 ± 2.0 °C, initial pH 7.0 ± 0.2 and inoculum size 10% (v/v) in the presence of light intensity 120–150 W/m2. Glucose and fructose (1.5%) was used as sole carbon source for comparison and 5.94 and 3.19 mol H2/mole sugar were obtained, respectively. Biohydrogen production of up to 357.3 ml/l at 40 °C and 142 ml/l even at 50 °C by SS-8 revealed some thermophilic nature of the microorganism. Kinetic study revealed biohydrogen production by an isolate was a biomass concentration associated function. However, improvement of this “one pot” process can be made through different parameter optimization. The results suggest the possibility of not only avoiding the need for pretreatment and hydrolysate detoxification but also reducing operational cost incurred on illuminating photobioreactors as sunlight, which is prevalent throughout the year in Pakistan.

Conversion of CaTi1–xMnxO3–δ-Based Photocatalyst for Photocatalytic Reduction of NO via Structure-Reforming of Ti-Bearing Blast Furnace Slag

In this work, a novel low-cost and robust approach is developed to covert Ti-bearing blast furnace slag (Ti-slag) to the main feed stock of photoassisted NH3 selective catalytic reduction (Photo NH...

Anhydrous bio-ethanol produced from Elaeis Guineensis palm wine for use as a biodiesel feedstock

Biofuel is an important alternative to the limited resources of fossil fuels for use in power generation. Currently, regular alcohol is used as a feedstock; however, it is known to be toxic. Hence, in this paper, we demonstrate that anhydrous alcohol obtained from palm wine is a potential alternative as the main feedstock for biofuel production. In this study, the aim was to improve the anhydrous alcohol obtained from palm wine based on storage conditions. Although this type of anhydrous alcohol has been previously produced, it is demonstrated that the current method is more efficient than the previous one. The processes implemented in this study were fractionation and extractive distillation. Two numerical simulations were carried out using extractive distillation processes to evaluate of an ethanol and water mixture, that is, ethylene glycol or glyceride. The palm wine was characterized based on the determination of the alcohol content, pH, acidity and the content of free SO2. The alcohol produced was characterized through the determination of its concentration, viscosity and density and infrared spectroscopy analysis. The results illustrate that it is possible to obtain excellent quality anhydrous alcohol suitable for small biofuel production, which is increasingly in demand in rural villages in Sub-Saharan Africa.

Bioaugmented methanol production using ammonia oxidizing bacteria in a continuous flow process

Organic compounds such as methanol are widely used for enhancing denitrification at wastewater treatment plants (WWTPs) to meet effluent water quality permits. On the other hand, methane, which is the main feedstock for industrial methanol production, is also generated during anaerobic digestion in WWTPs, but is often flared to mitigate its greenhouse impacts. The overarching goal herein was to develop a novel continuous process for methanol production from methane using nitrifying activated sludge. The maximum AOB specific methanol production rate using hydroxylamine as electron donor was 1.61 ± 0.15 and 1.27 ± 0.15 mg-COD-CH3OH/(mg-COD-AOB*d), for hydraulic retention times (HRTs) of 7.5 h and 2 h, respectively. The corresponding production rate using ammonia as electron donor was 0.31 ± 0.08 mg-COD-CH3OH/(mg-COD-AOB*d) at a HRT of 2 h. These results show that nitrifier-mediated methanol production in a continuous-flow system can enhance the efficiency of WWTPs through internal production of biomethanol for denitrification, while simultaneously minimizing wasteful biogas flaring.

Examining the Impact of Oil Price Change on the Economy through GDP Change

Petroleum economics is the field that studies human utilization of petroleum resources and the consequences of that utilization. Petroleum use allows the production of energy. Resources can be regarded as renewable or depletable; petroleum falls into the latter category, which can have an effect on pricing strategies. Crude oil is one of the main natural feedstocks used to meet energy demands and price variation has a significant influence on the society development. A large amount of research suggests that oil price fluctuations have considerable consequences on economic activity. These consequences are expected to be different in oil importing and in oil exporting countries. Whereas an oil price increase should be considered positive news in oil exporting countries and negative news in oil importing countries, the reverse should be expected when the oil price decreases. The paper investigates the co-movements and causality relationship between oil prices and GDP of selected oil exporting countries. Our assumption is decreasing oil prices have a negative impact on the GDP of such countries.

Food-Biofuels Interactions: The Case of the U.S. Biofuels Market

Corn refers to the main feedstock for U.S. biofuels production and together with soybean oil, as typical biofuel food commodity that can be converted into biodiesel, accounts for over 90 percent of biofuels production in the United States. The paper focuses on the nexus of agri-food and energy markets in U.S. and investigates the interrelationships between the biofuel prices and prices of soybean oil, corn and wheat. Co-integration analysis and vector error correction model are carried out in order to investigate the relationship between the price series. The results show that biofuels and food price levels are co-integrated in the long run. These links show that food prices increment with a rise in biofuels prices. Additionally, not only food prices are determined by biofuels prices, but also vice versa.

PENGARUH PROPORSI TEPUNG IKAN DAN TEPUNGKEONG MAS (Pomacea canaliculata) YANG BERBEDA SEBAGAI BAHAN BAKU UTAMA PEMBUATAN PAKAN TERHADAP PERTUMBUHAN BENIH UDANG VANNAMEI (Litopenaeus vannamei)

Feed is the main source of nutrients to support vannamei shrimp growth. The high cost of feed in operational costs due to the high raw material price of fish meal, limited availability, while the demand is high. Therefore it is necessary to find alternative materials that are low in price, have a high enough protein content and abundant availability such as golden snail flour. The purpose of this study was to analyze the effect of different proportion of fish meal and mashed snail (Pomacea canaliculata) as the main feedstock for the growth of shrimp vannamei (Litopenaeus vannamei). The experimental design used in this study was Completely Randomized Design (RAL) consisting of 5 treatments, namely A (57.18% use of fish meal in feed), B (42.89% use of fish meal, 14.30% mashed flour), C (28.59% fish meal usage, 28.59% mashed snail), D (Use of 14.30% fish meal, 42.89% mashed snail), and E (Use 57.18% golden snail flours). This study shows that the addition of mashed snail flour in the feed can increase the growth of absolute weight, the daily weight of vannamei shrimp, and can decrease the value of FCR.

Nitrate Reductase Inhibition Induces Lipid Enhancement of Dunaliella Tertiolecta for Biodiesel Production.

Nitrogen stress increases lipids content in microalgae, the main feedstock for algal biodiesel. Sodium tungstate was used in this study to implement nitrogen stress by inhibiting nitrate reductase (NR) in Dunaliella tertiolecta. The reduction of NR activity was accompanied by reduction of chlorophyll and accumulation of lipids. One-stage and two-stage culture strategies were compared. One-stage culture raised total lipids from 18% (control) to 39% (w: w); however, two-stage culture raised lipids to 50% in which neutral lipids were enhanced 2.14 times. To assess the quality of biodiesel produced, fatty acid methyl esters (FAME) composition was studied. It showed a slight variation of unsaturation. In addition, some physical proprieties of biodiesel were estimated and showed that higher heating values were improved by tungstate treatment. In this study, we tried to shed light on some biological impact of NR inhibition in microalgae cells using sodium tungstate which could be exploited in the improvement of biodiesel production.

Implementing a palm oil‐based biodiesel policy: The case of Thailand

AbstractRenewable energy promotion is recognized as an important goal in international climate policies in order to reduce CO2‐emissions. Biodiesel can potentially be an important contributor in this respect, especially in Thailand with its large biomass production from oil palm cultivation. Palm oil is the main raw feedstock for biodiesel production. However, biodiesel production is also controversial in many respects, in particular considering its sustainability. This paper assesses the collaboration between different actors in the Thai biodiesel and oil palm networks in organizing biodiesel provision. Through qualitative interviews with key political, economic, and societal actors the structure and the dynamic of the biodiesel and oil palm industry, as well as the relevant policy dynamics, were investigated. We found that the implementation of biodiesel policy was dominated by the need to secure the production of palm oil‐based cooking oil leading to frequent adjustments. Sustainable improvement and environmental considerations hardly played a role in the interactions between the actors involved in the palm oil and biodiesel industries. Government agencies were dominant and steered the biodiesel and the oil palm industries both directly and indirectly via economic and societal actors. Nevertheless, the promotion of biodiesel continues to be the basis of the national renewable energy master plan with its clear target to balance and stabilize the economic, social and environmental issues. As the renewable energy master plan does not fit with the possible feedstock, the main challenges in achieving these sustainable targets are therefore how to maintain a stable and consistent policy, especially concerning balancing the palm oil used for biodiesel production on the one hand and palm oil‐based cooking oil on the other.

Competitiveness analysis of “social soybeans” in biodiesel production in Brazil

Biodiesel production was stimulated in Brazil by the National Program for Production and Use of Biodiesel. The program has two objectives: ensuring both production and domestic consumption of biodiesel; and promoting diversification of feedstock sources, social inclusion, and regional development by generating employment and income for small rural farmers. However, despite the great potential for diversification of oilseed raw materials, soybeans make up the majority of the raw material that feeds the Brazilian biodiesel supply chain. Soybeans have two advantages: meeting the domestic demand for biodiesel; and having the most competitive prices, compared to other raw materials. Soybeans also support the social aspect of the federal program, although productive arrangements with small farmers are concentrated in the South region of Brazil. This paper characterizes the “social soybean” production chain for biodiesel production in Brazil and describes some of the competitive drivers that explain how soybeans from small farmers have been established as the main feedstock source. The paper also describes some bottlenecks and suggests actions that might address them in order to contribute to increased competitiveness of soybeans from small farmers in biodiesel production in Brazil.

Evaluation of wood pellet handling in import terminals

Wood pellet imports are expected to increase in the European Union and Southeast Asia by 2030, considering pellets are the main feedstock used for co-firing in power plants throughout these regions. Due to the material's physical and biological properties, the equipment at an import terminal need to be different than what is used for other bulk material. Thus, most of the common problems associated with handling can be avoided. Dust emission and explosions, degradation in storage, self-heating and ignition are important criteria when designing a wood pellet port terminal, and can greatly affect associated logistics. Despite some availability of data concerning the handling of pellets, there is a lack of insight into the equipment and operations of actual handling facilities. A detailed literature research was performed in order to ascertain the level of the scientific background on the subject. Subsequently, visits in pellet facilities in the Netherlands and in-depth interviews with representatives were conducted and serve as a means of gaining an overview of current industry practices and equipment used for the handling of wood pellets. The main objective of this work is to evaluate the state-of-the-art in wood pellet handling in import terminals. This way, future bottlenecks can be identified and actions needed to overcome them can be determined. The analysis performed shows that while wood pellet terminals might be able to cope with the low amounts being traded currently, a reexamination and redesign of terminal facilities to accommodate the increased volumes will probably be required by 2030.

The ethanol mandate and crude oil and biofuel agricultural commodity price dynamics

We investigate mean and volatility spillovers between the crude oil market and the main biofuel feedstock markets (corn, soybean, and sugar). In doing so, we estimate a four-variable vector error correction (VEC)–GARCH–in–Mean model with a BEKK representation for the variance equation, and also examine the possible effects of the ethanol mandate by including a dummy variable in both the conditional mean and variance equations. We find that the oil market and the biofuel feedstock markets are tightly interconnected and that the ethanol mandate has strengthened their linkages in terms of volatility spillovers.

Balancing Sodium Impurities in Alumina for Improved Properties

As there are direct and indirect impacts of feed material purity on the aluminum production process and metal grade, there is a high demand on the so-called pure smelter grade alumina (SGA)—the main feedstock for aluminum production. In this work, impurities within the precursor gibbsite used for SGA production and SGA are studied using NanoSIMS and XPS with a focus on sodium—the most abundant impurity. Although the industry trend is towards minimizing sodium due to the well-known negative impacts on the process, high sodium is also correlated with relatively attrition-resistant calcined products. Here, we show that this relationship is indirect and arises from sodium’s role in inhibiting α-alumina formation. Alpha alumina formation in SGA has previously been demonstrated to induce a macro-porous and therefore attrition-prone microstructure. Sodium distribution within the precursor gibbsite and its migration during the calcination process are proposed to be most likely responsible for the spatial distribution of α-alumina within the calcined product grain. This in turn determines the behavior of the product during its transportation and handling (i.e., attrition). Therefore, tolerance of a certain amount of sodium within the precursor material does demonstrate a net benefit while balancing its negative impacts on the process.

Comparative Exergetic Analysis of Two Biodiesel Production Routes

Biofuels, such as biodiesel has obtained more and more relevance in the national scenario, because of the current concerns related to the burning of fossil fuels, besides of laws in force that determine the increase of biodiesel blend in common diesel each year. Thus, in this study a comparative exergetic analysis was carried out between the biodiesel production from soybean oil via basic homogeneous catalysis, case 1, where sodium hydroxide (NaOH) was used as a catalyst, and by means of supercritical alcohol, case 2, in which methanol was led to critical state. For that, two production plants were simulated in Aspen HYSYS® V9 software accepting the same amount of main feedstock, in this case soybean oil. After the simulations, the exergetic efficiency of each process was calculated through to a global control volume (CV), having as result 94.01 and 93.50 % to the Case 1 and 2, respectively. These results confirm the feasibility of biodiesel production and the little exergetic difference was caused principally by the conditions of temperature and pressure that were imposed in the methanol supercritical case.

Hygienic-sanitary quality of Minas fresh cheese sold in the city of Botucatu, São Paulo

ABSTRACT: The Minas fresh cheese is a fresh and moist cheese and, therefore, has a short shelf-life. The use of raw milk as the main feedstock, the absence of ripening and the facility of contamination are factors that can compromise the product’s microbiological quality. The aim of this study was to describe the hygienic-sanitary quality of 50 Minas fresh cheeses marketed in Botucatu city, São Paulo, Brazil, close to their production date, and another 50 units from the same lot exactly on the expiration date, according to the Brazilian Sanitary Surveillance Agency (ANVISA). We also searched for enterotoxins genes in Staphylococcus aureus and its in vitro expression. In 36% of the first analyzed samples, the count of coliforms at 45ºC was above the limit and, as for the second analysis, 44%. Regarding coagulase positive staphylococci, 10 (20%) samples showed concentration above the permitted by law next to the production date and 14% on the expiration date. Salmonella was only observed in one sample analyzed near the date of production, while L. monocytogenes only in one sample analyzed on the expiration day. We isolated three enterotoxigenic strains of S. aureus that produced Staphylococcal Enterotoxin B (SEB) and Staphylococcal Enterotoxin C (SEC) in vitro, highlighting the importance of proper storage of this product due to its potential to cause intoxication. Overall, the quality of Minas fresh cheese is still unsatisfactory, leading to risks to consumers’ health.

On the challenges facing the handling of solid biomass feedstocks

AbstractWith a major global emphasis on the management of waste, alternative resources and a shift to environmentally sustainable technologies, demand for large volumes of heterogeneous solid biomass feedstocks for energy or chemical use is expected to rise significantly. In transforming a sporadic supply of a low‐value, highly variable product, to continuous and controlled high throughput systems, a thorough understanding of the feedstock properties will increase in importance. Appropriate characterisation tests are necessary to define technical specification and selection criteria for handling equipment and to appraise the requirement and location for additional processes or pre‐treatment to be integrated into the handling chain. Such tests may also influence the material characteristics to be used in the conversion process. This paper discusses the main feedstock attributes associated with a number of handling chain phases and the approach to obtain them. The framework for a holistic approach to the characterisation and design of biomass feedstock handling systems for further development and practical implementation is also proposed. © 2018 Society of Chemical Industry and John Wiley & Sons, Ltd

Conversion of Waste Tire Rubber into High-Value-Added Carbon Supports for Electrocatalysis

Carbon supports are vital for a wide range of electrochemical reactions, yet the production of useful carbon supports largely relies on costly precursors and fabrication methods. Here, we present a new economical process to fabricate carbon-based supports for electrocatalysts using recycled tire rubber as the main feedstock. Using the oxygen reduction reaction (ORR) as an example, we deposited Pt nanocubes on tire-derived carbon with different textural properties and surface chemistries. Our results show that Pt nanocubes are most effective toward the ORR when loaded onto tire-derived carbon with an increased electrochemically active surface area, a decreased average pore diameter, low sulfur content, and good crystallinity. These properties collectively allow for high dispersion of Pt nanocubes onto the tire-derived carbon support, and hence, increase the activity toward oxygen reduction. When benchmarked against a commercial carbon black support (Ketjen-300), the tire-derived carbon support achieved similar performance. Our results highlight an effective approach to converting waste tires into carbon supports for electrocatalysis.

The Ethanol Mandate and Crude Oil and Biofuel Agricultural Commodity Price Dynamics

We investigate mean and volatility spillovers between the crude oil market and the main biofuel feedstock markets (corn, soybean, and sugar). In doing so, we estimate a four-variable vector error correction (VEC) GARCH-in-Mean model with a BEKK representation for the variance equation, and also examine the possible effects of the ethanol mandate by including a dummy variable in both the conditional mean and variance equations. We find that the oil market and the biofuel feedstock markets are tightly interconnected and that the ethanol mandate has strengthened their linkages in terms of volatility spillovers.

Effect of bulking agents and cow dung as inoculant on vegetable waste compost quality

The source segregated vegetable waste (VW) was used as main feedstock and locally available organic wastes, such as water hyacinth (WH), garden prune (GP) and sawdust (SD) were used as bulking agents (BAs) to make the compost stable and mature in combination with cow dung (CD) as a source of inoculant. Three trials (T1, T2 & T3) were performed with a compost ratio of 6:3:1 (VW:BA:CD) using different BAs. The initial C/N ratio of all the trials was maintained lesser than 23 and composted for 30 days (7 days in rotary drum reactor + 23 days windrowing). The ANOVA analysis indicated that the physico-chemical parameters varied significantly (p < .05) with the time of composting. It was also indicated that SD is the most performing BA for North-eastern region of India due to optimum germination index of 110% along with leachate management.

How does technology pathway choice influence economic viability and environmental impacts of lignocellulosic biorefineries?

BackgroundThe need for liquid fuels in the transportation sector is increasing, and it is essential to develop industrially sustainable processes that simultaneously address the tri-fold sustainability metrics of technological feasibility, economic viability, and environmental impacts. Biorefineries based on lignocellulosic feedstocks could yield high-value products such as ethyl acetate, dodecane, ethylene, and hexane. This work focuses on assessing biochemical and biomass to electricity platforms for conversion of Banagrass and Energycane into valuable fuels and chemicals using the tri-fold sustainability metrics.ResultsThe production cost of various products produced from Banagrass was $1.19/kg ethanol, $1.00/kg ethyl acetate, $3.01/kg dodecane (jet fuel equivalent), $2.34/kg ethylene and $0.32/kW-h electricity. The production cost of different products using Energycane as a feedstock was $1.31/kg ethanol, $1.11/kg ethyl acetate, $3.35/kg dodecane, and $2.62/kg ethylene. The sensitivity analysis revealed that the price of the main product, feedstock cost and cost of ethanol affected the profitability the overall process. Banagrass yielded 11% higher ethanol compared to Energycane, which could be attributed to the differences in the composition of these lignocellulosic biomass sources. Acidification potential was highest when ethylene was produced at the rate of 2.56 × 10−2 and 1.71 × 10−2 kg SO2 eq. for Banagrass and Energycane, respectively. Ethanol production from Banagrass and Energycane resulted in a global warming potential of − 12.3 and − 40.0 g CO2 eq./kg ethanol.ConclusionsUtilizing hexoses and pentoses from Banagrass to produce ethyl acetate was the most economical scenario with a payback period of 11.2 years and an ROI of 8.93%, respectively. Electricity production was the most unprofitable scenario with an ROI of − 29.6% using Banagrass/Energycane as a feedstock that could be attributed to high feedstock moisture content. Producing ethylene or dodecane from either of the feedstocks was not economical. The moisture content and composition of biomasses affected overall economics of the various pathways studied. Producing ethanol and ethyl acetate from Energycane had a global warming potential of − 3.01 kg CO2 eq./kg ethyl acetate.