Biofuel By-products Research Articles

Pilot-scale extraction of multiple biopesticidal compounds from mustard biofuel by-products

Oils from Sinapis alba and Brassica juncea mustards can be used as a raw material for biofuel and biodiesel. Mustard seed meal left after oil extraction is considered a low value by-product. Valorization of mustard meal into biopesticide is one of the promising directions. The development of a suitable pilot scale extraction and concentration procedure is the first critical step to achieve this goal. Thus, the objective of the presented work was to develop a scaled-up process for producing mustard seed meal biopesticides. Modular pilot plant was built to allow for up to 100 gallons extraction capacity. The pilot plant setup included components that are widely accessible and can be adjusted to meet a range of production scales. The ratio of mustard seed meal to water, temperature, and extraction times were optimized for extraction of major mustard biopesticidal compounds (ionic thiocyanate, 4-hydroxybenzyl alcohol, and sinigrin). To evaluate the potential as an animal feed and further valorization of mustard seed meal, extracted mustard seed meals were analyzed for chemical composition. Based on total digestible nutrients and net energies, both B. juncea and S. alba extracted mustard seed meals were siutable animal feed for dairy cows.

Co-digestion of biofuel by-products: Enhanced biofilm formation maintains high organic matter removal when methanogenesis fails

Ethanol and biodiesel industries generate large volumes of by-products, such as vinasse and glycerol, which are suitable for biogas exploitation. This paper assessed the applicability and process performance of the anaerobic structured-bed reactor (AnSTBR) for the mesophilic (30 °C) continuous (105 days) anaerobic co-digestion of sugarcane vinasse and distilled glycerol under increasing organic loading rates (OLR) (0.5–5.0 kgCOD m−3d−1). The highest methane yield (211 NmL g−1CODrem.) and volumetric production (668 NmL L−1d−1) occurred at an OLR of 3.5 kgCOD m−3d−1. The performance of the AnSTBR showed high removal efficiencies of total COD (77.1%), carbohydrates (81.9%), and glycerol content (99.7%). Biofilm growth enhancement within the reactor offset the impairment of methanogenesis activity at high organic loads. The prompt biodegradability of glycerol reinforced the importance of gradually increase the organic load to prevent the buildup of volatile acids and maintain a stable long-term co-digestion system.

Redox Status, Biochemical Parameters and Mineral Elements Content in Blood of Turkey Hens Fed a Diet Supplemented with Yarrowia lipolytica Yeast and Two Bacillus Species.

Simple SummaryInterest in Yarrowia lipolytica (YL) arises from the fact that it grows on the crude glycerol fraction derived from the production of diesel oil, so that it constitutes a link between biofuel by-products and animal feed. Studies have already been conducted on the use of Yarrowia lipolytica as a factor affecting the gut microbiota and fattening efficiency of turkeys, and the results have been promising. However, it has not been clarified whether Yarrowia lipolytica yeast can improve the availability of minerals as well as metabolic processes associated with redox reactions like Saccharomyces cerevisiae (SC). The research shows that, Yarrowia lipolytica yeast stimulates more effectively antioxidant processes than Saccharomyces cerevisiae, and also improves the absorption of minerals. Therefore, it may be a more effective additive than the widely used Saccharomyces cerevisiae yeast in turkey feed. In addition, the experiment confirmed that the antioxidant effect of fodder yeast (especially Yarrowia lipolytica) can be enhanced by combining it with a probiotic bacteria. Hence, the combined use of yeast with a Bacillus species can be recommended in cases of the stimulation of oxidative reactions (e.g., stress or infection).The probiotic-prebiotic properties and chemical composition of Yarrowia lipolytica yeast (YL), predisposes it for use as a turkey feed additive. The aim of the study was to determine whether YL in the diet of turkeys would exert more beneficial effect by stimulating antioxidant reactions and increasing mineral availability than Saccharomyces cerevisiae (SC). An additional aim of the study was to test whether the addition of a probiotic bacteria to feed containing Yarrowia lipolytica or Saccharomyces cerevisiae yeast would enhance their effect. The study was conducted on turkeys from seven to 112 days of age to determine the effects of a 3% addition of YL to the diet, as an alternative to the standard SC. It was analysed whether the use of a probiotic (Bacillus licheniformis, Bacillus subtilis) together with yeast would be more effective. Both the yeast (YL or SC) and the probiotic stimulated antioxidant mechanisms (increased CAT; reduced MDA), but the addition of SC was less effective. The inclusion of YL in the feed increased the plasma content of Ca, Mg, Cu, Zn and Fe in the blood turkeys and lowered the content of cholesterol and triacylglycerols. The combined use of yeast (YL or SC) with a probiotic enhances the antioxidant effect while inhibiting of lipid peroxidation. The combined use of yeast with a probiotic can be recommended in cases of stimulation of oxidative reactions (e.g., stress or infection)

Burkholderia glumae MA13: A newly isolated bacterial strain suitable for polyhydroxyalkanoate production from crude glycerol

Abstract Burkholderia glumae MA13 was isolated from soil samples of Atlantic rain forest ecosystem as a new bacterial strain for polyhydroxyalkanoate (PHA) production from crude glycerol as sole carbon source. Among 107 glycerol consuming bacterial isolates, B. glumae MA13 was cultivated in shake flask experiments in order to verify its PHA production capability from crude glycerol besides waste cooking oil and sugarcane molasses free of pretreatment, showing intracellular poly(3-hydroxybutyrate) [P(3HB)] accumulation values of 51.3, 51.4 and 49% of cell dry weight (CDW), respectively. The addition of propionic or hexanoic acids to the media containing crude glycerol resulted in the copolymers poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] comprised of up to 32.1 mol% of 3HV monomer or poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) [P(3HB-co-3HHx)] with a maximum of 0.3 mol% of 3HHx, respectively. Fed-batch cultivation performed in a 10 L-scale bioreactor showed a maximum P(3HB-co-3HV) production of 9.9 g/L, which was 65.1% of total biomass and consisted of 21.8 mol% of 3HV monomer, with a maximum volumetric productivity of 0.22 g/(L h). The 3HV conversion yield achieved 1.04 g/g after 48 h cultivation, which was 76.7% of the maximum theoretical yield. B. glumae MA13 has showed to be an adapted bacterial strain to the synthesis of bioplastics from biofuel byproducts, and so from here it has been revealed as a promising PHA producer for an associated production set which has been considered as a prominent and ecologically friendly alternative to petrochemical plastics and fuels.

Glycerol use in dairy diets: A systemic review.

There is an increasing interest in the production of biodiesel as bio-renewable fuel source, with numerous biofuel byproducts becoming available. The annual productions of biodiesel and crude glycerol were 34.5 and 3.8 billion liters, respectively, in 2016 and that of biodiesel is expected to reach 41 billion liters in 2019. Glycerol is a sugar alcohol without a color or odor, but with a sweet taste and high solubility index in water. Experiments support the use of glycerol at low levels ranging from 5% to 8% of the diet dry matter as a transition cow therapy. Administration of glycerol increases serum glucose and decreases ketone bodies. Glycerol is very rapidly fermented in the rumen to propionate and butyrate, at the expense of acetate, resulting in a decreased milk fat. Because glycerol is highly fermented in the rumen, it requires an adaptation period at the beginning of feeding. Administration of glycerol in the diet of lactating animals was paralleled with a decreased or an unaffected feed intake in most experiments. Improved ruminal environment to enhance nutrient digestibility was observed in many experiments; however, others observed reduced digestion of dietary fiber with feeding glycerol. Enhanced, lowered, or unaffected milk production and composition were observed with the administration of glycerol in lactating animal diets; however, in most cases, glycerol decreased milk fat content. The inconsistencies between results of experiments are due to the level and the purity of glycerol, diets, production stage of the animals, and other factors. Therefore, further research should be conducted to establish the efficacy of different levels, purity and administration periods of glycerol, and production stage of dairy animals fed glycerol-based or supplemented diets.

Surface tension and wetting properties of rapeseed oil to biofuel conversion by-products

AbstractThis work presents a study on the surface tension, density and wetting behaviour of distilled glycerol, technical grade glycerol and the matter organic non-glycerin fraction. The research was conducted to expand the knowledge about the physical properties of wastes from the rapeseed oil biofuel production. The results show that the densities of technical grade glycerol (1.300 g cm-3) and distilled glycerol (1.267 g cm-3) did not differ and were significantly lower than the density of the matter organic non-glycerin fraction (1.579 g cm-3). Furthermore, the surface tension of distilled glycerol (49.6 mN m-1) was significantly higher than the matter organic non-glycerin fraction (32.7 mN m-1) and technical grade glycerol (29.5 mN m-1). As a result, both technical grade glycerol and the matter organic non-glycerin fraction had lower contact angles than distilled glycerol. The examined physical properties of distilled glycerol were found to be very close to that of the commercially available pure glycerol. The results suggest that technical grade glycerol may have potential application in the production of glycerol/fuel blends or biosurfactants. The presented results indicate that surface tension measurements are more useful when examining the quality of biofuel wastes than is density determination, as they allow for a more accurate analysis of the effects of impurities on the physical properties of the biofuel by-products.

Short-term interaction between organic matter from biofuel defatted seed cakes and soil microbiota in two intensive horticulture systems

In the last decades, use of biodiesel, produced by oil seeds, has widely increased. Defatted seed cakes are the most important byproducts of biodiesel production chain and their agricultural valorization is becoming a global challenge. The aim of this study was to characterize carbon molecular composition of several seed cakes (Brassica carinata A. Braun, Brassica napus L. and several components of Helianthus annuus L. seed wastes) by means of 13C CPMAS-NMR spectroscopy and evaluate their short-term effects on soil microbial activities, in two intensive horticulture systems. Defatted seed cakes used in this study have relevant differences in chemical composition and significant conditioning effects on soil microbiota. Seed cakes from sunflower were characterized by a higher content of celluloses, as carbohydrates composition, while Brassicaceae seed cakes were rich in more biochemical stable compounds and secondary metabolites, such as glucosinolates precursors of anti-microbial molecules. These latter ones, along with the larger amount of carbon molecules with an highest biochemical stability, negatively affected microbial growth resulting, generally, in lower soil activities. In conclusion, this study unraveled, for the first time, the molecular carbon composition of several biofuel byproducts and showed how the seed cakes can be evaluate for soil amendments, thus permitting to convert byproducts from biofuel chain to co-products useful in agriculture.

Quality of Rapeseed Bio-Fuel Waste: Optical Properties

Abstract The objective of the presented work was to examine the optical properties of selected bio-fuel waste. Three independent optical methods: UV-Vis spectroscopy, infrared spectroscopy and chromametric measurements were applied to establish the possible quality control test for the obtained substances. The following by-products were tested: distilled glycerine, technical glycerine and matter organic non glycerine fraction from rapeseed oil bio-fuel production. The results show that analysis of UV-Vis spectra can give rapid information about the purity of distilled glycerine, while no direct information can be obtained concerning the concentration and kind of impurities. Transmission mode is more useful as compared to absorption, concerning the detection abilities of average UV-Vis spectrometers. Infrared spectroscopy can be used as a complementary method for determining impurities/admixtures in samples. Measurements of chroma give the quickest data to compare the colour of biofuel by-products obtained by different producers. The condition is, however, that the products are received through the same or similar chemical processes. The other important factor is application of well defined measuring background. All the discussed analyses are quick, cheap and non-destructive, and can help to compare the quality of products.

MODELING LAND-USE CHANGE IMPACTS OF BIOFUELS IN THE GTAP-BIO FRAMEWORK

This paper reviews an analysis of land use change impacts of expanded biofuel production with GTAP-BIO computable general equilibrium (CGE) model. It describes the treatment of energy substitution, the role of biofuel by-products, specification of bilateral trade, the determination of land cover changes in response to increased biofuel feedstock production, and changes in crop yields – both at the intensive and extensive margins. The paper responds to some of the criticisms of GTAP-BIO and provides insights into the sensitivity of land use change and GHG emissions to changes in key parameters and assumptions. In particular, it considers an alternative specification of acreage response that takes into account the degree of land heterogeneity within agro-ecological zone (AEZ) for different AEZs and countries. The paper concludes with the discussion of alternative specifications of land mobility across uses employed in CGE models and the agenda for further research to narrow parametric and structural uncertainty to improve the model's performance.

Greenhouse gas emissions and nutrient supply rates in soil amended with biofuel production by-products

Ethanol production results in distiller grain, and biodiesel produces glycerol as by-product. However, there is limited information on effects of their addition on evolution of N2O and CO2 from soils, yet it is important to enable our understanding of impacts of biofuel production on greenhouse gas budgets. The objective of this study was to evaluate the direct effects of adding wet distillers grain (WDG), thin stillage (TS), and glycerol at three rates on greenhouse gas emissions (N2O and CO2) and nutrient supply rates in a cultivated soil from the Canadian prairies. The WDG and TS application rates were: 100, 200, or 400 kg N ha−1, whereas glycerol was applied at: 40, 400, or 4,000 kg C ha−1 applied alone (G − N) or in a combination with 300 kg N ha−1 (G + N). In addition, conventional amendments of urea (UR) and dehydrated alfalfa (DA) were added at the same rates of total N as the by-products for comparative purposes. The production of N2O and CO2 was measured over an incubation period of 10 days in incubation chambers and Plant Root Simulator™ resin membrane probes were used to measure nutrient (NH 4 + -N, NO 3 − -N, and PO 4 −3 -P) supply rates in the soil during incubation. Per unit of N added, urea tended to result in the greatest N2O production, followed by wet distillers grain and thin stillage, with glycerol and dehydrated alfalfa resulting in the lowest N2O production. Cumulative N2O production increased with increasing the rate of N-containing amendments and was the highest at the high rate of UR treatment. Addition of urea with glycerol contributed to a higher rate of N2O emission, especially at the low rate of glycerol. The DA and WDG resulted in the greatest evolution of CO2 from the soil, with the thin stillage resulting in less CO2 evolved per unit of N added. Addition of N fertilizer along with glycerol enhanced microbial activity and decomposition. The amendments had significant impacts on release of available nutrient, with the UR treatments providing the highest NO 3 − -N supply rate. The TS treatments supplied the highest rate of NH 4 + -N, followed by WDG compared to the other amendments. The WDG treatments were able to provide the greatest supply of PO 4 −3 -P supply in comparison to the other amendments. Microbial N immobilization was associated with glycerol treatments applied alone. This study showed that the investigated biofuel by-products can be suitable soil amendments as a result of their ability to supply nutrients and N2O emissions that did not exceed that of the conventional urea fertilizer.

Jatropha as energy potential biofuel in Tanzania

People living in the large part of the African, Asian and Latin American continents often lack access to energy sources in general. One approach to provide these people with energy to increase living standards is to enable them produce energy from local resources. A promising local renewable energy source for people living in tropical regions is Jatropha curcas (Linnaeus), in which biodiesel can be sourced from its fruits. The byproducts from biodiesel are of potential as well in renewable energy sources. Energy contribution from by products include the utilization utilization of fruit shells briquettes as an energy source, production of chemicals from biofuel byproducts such as gryceline, biogas production from the press cake.. Biomass serves as the major source of energy in Tanzania providing about 90% of the total energy consumed and energy from oil and gas provides about 7% of the consumed energy. The results from two scenarios in this study indicated a positive contribution of the Jatropha bioenergy system to the energy sector in Tanzania. Jatropha press cake biogas alone has a potential to contribute 25% to 134% of the national annual electricity per capita by the year 2015, while adding more than 50% oil obtained after pressing of Jatropha seeds. However, biofuel investment and production is a highly contentious issue. Critical aspects to consider on Jatropha cultivation in Tanzania include water distribution and usage, food security, environmental conservation and biodiversity, social impacts and economic issues. Lastly, this study concludes that biorefinery of Jatropha products will offer more energy contribution, wastes reduction and more value to Tanzania biofuel industry, particularly Jatropha bioenergy system.

Approach for a pro-active emerging risk system on biofuel by-products in feed

Worldwide biofuel products have rapidly entered the market and consequently so did the availability of their by-products for feed production. A pro-active emerging risk system for biofuel by-products is essential in order to prevent the occurrence of emerging hazards in feed and livestock production. In the current study, two biofuel by-products were elaborated upon, namely Dried Distillers Grains with Solubles (DDGS) resulting from bioethanol production and microalgae slurry resulting from biodiesel production. A holistic approach was used in which both factors from within the feed chain as well as outside the feed chain were incorporated. A list of critical factors linking dynamics in the biofuel production chain with possible feed safety risks was established after consultation of experts in in-depth interviews. Subsequently, a workshop was organized to determine the most important critical factors. Indicators (signals that indicate a change in critical factors) and information sources were linked to these factors for the individual cases. Based on expert judgment, the most important critical factors identified for the two selected cases were: chain complexity, composition of the feed product, origin of raw materials and climate change. Ranking of the indicators showed that in both cases the number of chain stages was the most important general indicator for feed safety risks. The study showed that following this approach resulted in the selection of critical factors and indicators for emerging feed safety risks related to the use of biofuel by-products. Once critical values (upper and/or lower limits) are assigned to the indicators, the system can support decisions to take actions in an early stage in order to prevent emerging risks in feed due to the use of DDGS or microalgae slurry.

Implications of biofuels mandates for the global livestock industry: a computable general equilibrium analysis

The rapid growth of biofuels production, particularly in the United States, the EU, and Brazil, has had important implications for the global livestock industry—both by raising the cost of feed grains and oilseeds and by forcing onto the market a large supply of biofuel by-products, most of which end up in livestock feed rations. This article investigates the impact of an expanding biofuels industry on the mix and location of global livestock production. Surprisingly, we find that growth in the U.S. and EU biofuels industries results in larger absolute reductions in livestock production overseas than in those regions, due to the international transmission of grains prices which is offset locally by the lower cost of by-products. We also find that nonruminant production is cut more than ruminant livestock, because it is less able to use biofuel by-products in its feed rations. Implementing biofuel mandates increases cropland area, a large portion of which is estimated to come from reduced grazing lands. The biofuel producing regions are expected to reduce their coarse grains exports and increase imports of oilseeds and vegetable oils, while they increase their exports of processed feed materials. In sum, biofuel mandates have important consequences for livestock as well as crops, with net effects influenced by the important role of by-products in substituting for feedstuffs.

White paper report from working groups attending the international conference on research and educational opportunities in bio-fuel crop production

A conference on current research and educational programs in production of crops for bio-fuel was sponsored and organized by the EARTH University and the University of Florida in November, 2008. The meeting addressed current research on crops for bio-fuel production with discussions of research alternatives for future crop production systems, land use issues, ethics of food vs. fuel production, and carbon sequestration in environmentally sensitive tropical and sub-tropical regions of the Americas. The need and potential for development of graduate and undergraduate curricula and inter-institutional cooperation among educational institutions in the region were also discussed. Delegations from Belize, Brazil, Columbia, Costa Rica, Cuba, Honduras, Panama, The Dominican Republic, and the United States including ministers of Agriculture and Energy attended this meeting. Over a two-day period, four working groups provided a framework to facilitate networking, motivate task oriented creative thinking, and maintain a timely accomplishment of assigned duties in the context of the conference themes. Participants in the conference were assigned to one of four working groups, each following given topics: Agronomy, Environment, Socio-Economics and Education/Extension. It was the consensus of representatives of industry, academic and regulatory community assembled in Costa Rica that significant research, education and socio-economic information is needed to make production of bio-fuel crops sustainable. Agronomic research should include better crop selection based on local conditions, improved production techniques, pest and disease management, and mechanical cultivation and harvesting. Another conclusion was that tailoring of production systems to local soil characteristics and use of bio-fuel by-products to improve nutrient use efficiency and reduction of environmental impact on water quantity and quality is critical to sustainability of bio-fuel crop production.

Mineralization of Nitrogen from Biofuel By-products and Animal Manures Amended to a Sandy Soil

Transformations of nitrogen (N) from poultry litter (PL), dairy manure compost (DMC), anaerobically digested fiber (ADF), Perfect Blend 7–2–2 (PB), a compost/litter mixture (C/L), dried distillers grains from ethanol production (DG), and mustard meal from biodiesel production (MM) applied to a Quincy fine sand were investigated in an incubation experiment over 210 days. The cumulative release totals of available N after 210 days were 61, 61, 56, 44, 29, 2, and –2% for the total N in MM, PB, DG, PL, C/L, DMC, and ADF, respectively. With application of MM and DG, ammonium (NH4-N) accumulated initially in the soil with very little nitrification, possibly because of inhibition of nitrification related to chemical compounds in the amendments. Mineralization of organic N to NH4-N and nitrate (NO3-N) was relatively slow from MM- and DG-amended soils, indicating the potential for using biofuel by-products as slow-release N sources for plants.

Biofuels and their by-products: Global economic and environmental implications

Abstract Recently a number of papers have used general equilibrium models to study the economy-wide and environmental consequences of the first generation of biofuels (FGB). In this paper, we argue that nearly all of these studies have overstated the impacts of FGB on global agricultural and land markets due to the fact that they have ignored the role of biofuel by-products. Feed by-products of FGB, such as dried distillers grains with solubles (DDGS) and oilseed meals (VOBP), are used in the livestock industry as protein and energy sources. Their presence mitigates the price impacts of biofuel production. More importantly, they reduce the demand for cropland and moderate the indirect land use consequences of FGB. This paper explicitly introduces DDGS and VOBP into a global computational general equilibrium (CGE) model, developed at the Center for Global Trade Analysis at Purdue University, to examine the economic and environmental impacts of regional and international mandate policies designed to stimulate bioenergy production and use. We show that models with and without by-products reveal different portraits of the economic impacts of the US and EU biofuel mandates for the world economy in 2015. While both models demonstrate significant changes in the agricultural production pattern across the world, the model with by-products shows smaller changes in the production of cereal grains and larger changes for oilseeds products in the US and EU, and the reverse for Brazil. Models that omit by-products are found to overstate cropland conversion from US and EU mandates by about 27%.