Convergence of Agriculture and Energy: III. Considerations in Biodiesel Production

Concern about rising prices and unstable sources of petroleum fuels is driving the search for U.S. domestically produced, renewable transportation fuels, such as biodiesel. Federal incentives of up to $1.10 per gallon have been supplemented by additional incentives and mandated biodiesel use in many states. The Renewable Fuel Standard in the Energy Independence and Security Act of 2007 requires the domestic use of 1 billion gallons of biomass-based diesel fuel by 2012, most of which likely will be biodiesel. U.S. biodiesel production is primarily from soybean oil, but recent high prices have forced many producers to use lower-cost feedstocks such as animal fats and used frying oils. A large portion of domestic production currently is exported to Europe, where the devalued dollar and combined U.S. and European subsidies contribute to the competitive price of imported biodiesel. Although vegetable oils can be used directly in diesel engines, experience has shown that excessive deposits in the engine cylinder degrade engine performance and increase emissions over time. Conversion to methyl esters allows vegetable oil to be used in diesel engines with fewer problems. These methyl esters have become known as “biodiesel.” This document reviews the technology of biodiesel production and the issues and policy implications associated with the expanded use and production of biodiesel

Motor complications in an incident Parkinson’s disease cohort

Acknowledgements We acknowledge funding for the PINE study from Parkinson's UK, the Scottish Chief Scientist Office, the BMA Doris Hillier Award, RS Macdonald Trust, the BUPA Foundation, NHS Grampian Endowments and SPRING. We thank the patients for their participation and the research staff who collected data and supported the study database. Nicholas W Scott: no financial disclosures. Angus D Macleod: funded by a Clinical Academic Fellowship from the Scottish Chief Scientist Office; also received research funding from Parkinson's UK. Carl E Counsell: research funding from Parkinson's UK, Scottish Chief Scientist Office, National Institute of Health Research, and Engineering and Physical Sciences Research Council.Peer reviewedPostprin

Orthostatic Tremor and Orthostatic Myoclonus: Weight-bearing Hyperkinetic Disorders: A Systematic Review, New Insights, and Unresolved Questions

Background: Orthostatic tremor (OT) and orthostatic myoclonus (OM) are weight-bearing hyperkinetic movement disorders most commonly affecting older people that induce “shaky legs” upon standing. OT is divided into “classical” and “slow” forms based on tremor frequency. In this paper, the first joint review of OT and OM, we review the literature and compare and contrast their demographic, clinical, electrophysiological, neuroimaging, pathophysiological, and treatment characteristics. Methods: A PubMed search up to July 2016 using the phrases “orthostatic tremor,” “orthostatic myoclonus,” “shaky legs,” and “shaky legs syndrome” was performed. Results: OT and OM should be suspected in older patients reporting unsteadiness with prolonged standing and/or who exhibit cautious, wide-based gaits. Surface electromyography (SEMG) is necessary to verify the diagnoses. Functional neuroimaging and electrophysiology suggest the generator of classical OT lies within the cerebellothalamocortical network. For OM, and possibly slow OT, the frontal, subcortical cerebrum is the most likely origin. Clonazepam is the most useful medication for classical OT, and levetiracetam for OM, although results are often disappointing. Deep brain stimulation appears promising for classical OT. Rolling walkers reliably improve gait affected by these disorders, as both OT and OM attenuate when weight is transferred from the legs to the arms. Discussion: Orthostatic hyperkinesias are likely underdiagnosed, as SEMG is often unavailable in clinical practice, and thus may be more frequent than currently recognized. The shared weight-bearing induction of OT and OM may indicate a common pathophysiology. Further research, including use of animal models, is necessary to better define the prevalence and pathophysiology of OT and OM, in order to improve their treatment, and provide additional insights into basic balance and gait mechanisms

Apparatus for recovery and use of waste thermal energy

Energy recovery apparatus for recovering and using thermal energy comprises multiple series of shape memory elements having decreasing transformation temperatures from one element to the next in the direction of a heating fluid to extract heat over a range of fluid temperatures to effect a shape change of each element. Cooling fluid is flowed alternately through each series of elements to cool the elements and effect another shape change. The cooling fluid exiting a preceding series of elements is used as the heating fluid of the next series of elements to extract further heat indirectly from the original heating fluid. The shape changes of the elements are converted to mechanical work

BIODIESEL PRODUCTION FROM OILS AND FATS WITH HIGH FREE FATTY ACIDS

ABSTRACT. Biodiesel is an alternative fuel for diesel engines consisting of the alkyl monoesters of fatty acids from vegetable oils or animal fats. Most of the biodiesel that is currently made uses soybean oil, methanol, and an alkaline catalyst. The high value of soybean oil as a food product makes production of a cost–effective fuel very challenging. However, there are large amounts of low–cost oils and fats such as restaurant waste and animal fats that could be converted to biodiesel. The problem with processing these low cost oils and fats is that they often contain large amounts of free fatty acids (FFA) that cannot be converted to biodiesel using an alkaline catalyst. In this study, a technique is described to reduce the free fatty acids content of these feedstocks using an acid–catalyzed pretreatment to esterify the free fatty acids before transesterifying the triglycerides with an alkaline catalyst to complete the reaction. Initial process development was performed with synthetic mixtures containing 20 % and 40 % free fatty acids, prepared using palmitic acid. Process parameters such as the molar ratio of alcohol, type of alcohol, acid catalyst amount, reaction time, and free fatty acids level were investigated to determine the best strategy for converting the free fatty acids to usable esters. The work showed that the acid level of the high free fatty acids feedstocks could be reduced to less than 1 % with a 2–step pretreatment reaction. The reaction mixture was allowed to settle between steps so that the water–containing alcohol phase could be removed. The 2–step pretreatment reaction was demonstrated with actual feedstocks, including yellow grease with 12 % free fatty acids and brown grease with 33 % free fatty acids. After reducing the acid levels of these feedstocks to less than 1%, the transesterification reaction was completed with an alkaline catalyst to produce fuel–grade biodiesel

Emission Control in Diesel Engines By Alcohol Fumigation

Exhaust emissions from diesel engines are a substantial source of air pollution in this country. In recognition of this fact, the Environmental Protection Agency has issued strict new regulations due to take effect -in 1991 and 1994 that will drastically reduce the amount of some pollutants these engines will be allowed to emit. The technology is not currently available to produce diesel engines that can meet these regulations without large penalties in engine performance and efficiency. One technique that offers promise of being able to reduce emissions from both existing engines and new engines is alcohol fumigation

Improved Soybean Oil for Biodiesel Fuel

The goal of this program was to generate information on the utility of soybean germplasm that produces oil, high in oleic acid and low in saturated fatty acids, for its use as a biodiesel. Moreover, data was ascertained on the quality of the derived soybean meal (protein component), and the agronomic performance of this novel soybean germplasm. Gathering data on these later two areas is critical, with respect to the first, soybean meal (protein) component is a major driver for commodity soybean, which is utilized as feed supplements in cattle, swine, poultry and more recently aquaculture production. Hence, it is imperative that the resultant modulation in the fatty acid profile of the oil does not compromise the quality of the derived meal, for if it does, the net value of the novel soybean will be drastically reduced. Similarly, if the improved oil trait negative impacts the agronomics (i.e. yield) of the soybean, this in turn will reduce the value of the trait. Over the course of this program oil was extruded from approximately 350 bushels of soybean designated 335-13, which produces oil high in oleic acid (>85%) and low in saturated fatty acid (<6%). As predicted improvement in cold flow parameters were observed as compared to standard commodity soybean oil. Moreover, engine tests revealed that biodiesel derived from this novel oil mitigated NOx emissions. Seed quality of this soybean was not compromised with respect to total oil and protein, nor was the amino acid profile of the derived meal as compared to the respective control soybean cultivar with a conventional fatty acid profile. Importantly, the high oleic acid/low saturated fatty acids oil trait was not impacted by environment and yield was not compromised. Improving the genetic potential of soybean by exploiting the tools of biotechnology to improve upon the lipid quality of the seed for use in industrial applications such as biodiesel will aid in expanding the market for the crop. This in turn, may lead to job creation in rural areas of the country and help stimulate the agricultural economy. Moreover, production of soybean with enhanced oil quality for biodiesel may increase the attractiveness of this renewable, environmentally friendly fuel

Physical Properties of Normal Grade Biodiesel and Winter Grade Biodiesel

In this study, optical and thermal properties of normal grade and winter grade palm oil biodiesel were investigated. Surface Plasmon Resonance and Photopyroelectric technique were used to evaluate the samples. The dispersion curve and thermal diffusivity were obtained. Consequently, the variation of refractive index, as a function of wavelength in normal grade biodiesel is faster than winter grade palm oil biodiesel, and the thermal diffusivity of winter grade biodiesel is higher than the thermal diffusivity of normal grade biodiesel. This is attributed to the higher palmitic acid C16:0 content in normal grade than in winter grade palm oil biodiesel

Experimental and modelling studies on continuous synthesis and refining of biodiesel in a dedicated bench scale unit using centrifugal contactor separator technology

Continuous synthesis and refining of biodiesel (FAME) using a laboratory scale bench scale unit was explored. The unit consists of three major parts: (i) a continuous centrifugal contactor separator (CCCS) to perform the reaction between sunflower oil and methanol; (ii) a washing unit for the crude FAME with water/acetic acid consisting of a mixer and a liquid-liquid separator; and (iii) a FAME drying unit with air. The continuous setup was successfully used for a 4 h runtime without any operational issues. The CCCS was operated at an oil flow rate of 32 mL/min, rotational speed of 35 Hz, 60 degrees C, a catalyst concentration of 1.2% w/w and a methanol flow rate of 10 mL/min. The flow rate of water (containing 1% w/w acetic acid) for the biodiesel washing unit was 10 mL/min (20 degrees C); the air flow rate (5% humidity) was set at 12 L/min. After 4 h runtime, approximately 7 kg of refined FAME was produced from a cumulative sunflower oil feed of 7.07 kg. The ester content of the refined FAME was 98% w/w (GC). Other relevant product properties were also determined and most were shown to meet the ASTM specifications. The refining section was modelled and optimised using ASPEN software.Practical applications: Synthesis and refining of sunflower biodiesel was successfully performed in a dedicated bench scale unit using centrifugal contactor separator technology. Besides for large scale biodiesel production, this technology has particularly potential to be applied in small mobile biodiesel units due to the compact size, robustness, flexibility in operation and high volumetric productivity of the CCCS devices.</p

Expanded phenotype in a patient with spastic paraplegia 7

No abstract available