scholarly journals Folytonos anyagtovábbítású mikrohullámú kezelőegység fejlesztése

2013 ◽  
Vol 8 (1-2) ◽  
pp. 59-63
Author(s):  
Róbertné V. P. Kovács ◽  
Sándor Beszédes ◽  
Lajos Ludányi ◽  
Cecilia Hodúr ◽  
Gábor Szabó
Keyword(s):  
Food Industry ◽  
Biogas Production ◽  
Complex Structure ◽  
Cavity Resonator ◽  
Microwave Treatment ◽  
Environmental Concerns ◽  
Pre Treatment ◽  
The University ◽  
Anaerobic Digestibility ◽  
Toroidal Cavity

Most branches in the food industry have a considerable wastewater output. The problem is not only the total amount of wastewater production, but also the high content of organic matter. Anaerobic digestion is an effective way of treating wastewater for yielding profitable biogas and alleviating environmental concerns. Pre-treatment of sludge to break down its complex structure can be used for enhancing anaerobic digestibility. Research group of the Department of Process Engineering at the University of Szeged has investigated the applicability and the efficiency of microwave pre-treatment for food industry sludge. The results showed that the microwave treatment of sludge solution resulted in higher biodegradability and enhanced biogas production as well. According to these results a continuous-flow microwave toroidal cavity resonator treating-system was developed.

scholarly journals Assessment of energy generated by biogas production in the educational industrial unit of the University of Szeged, Faculty of Agriculture, with special regard to biomass originating from agriculture and the food industry

2007 ◽  
pp. 137-140
Author(s):  
László Sallai
Keyword(s):  
Food Industry ◽  
Waste Treatment ◽  
Biogas Production ◽  
Effective Means ◽  
Animal Dung ◽  
Pig Farm ◽  
Industrial Unit ◽  
Available Technology ◽  
The University ◽  
Common Application

The importance of waste treatment is increasing. Environmental aims are the main driving force. Stricter regulations for landfills lead to the development of alternative treatment methods for waste. For agro-mechanical research, wastes from animal rearing and the food industry, secondary-tertiary biomass, is of deep concern. Available technology is versatile and relatively simple to use as a reliable and effective means of producing a gaseous fuel from various organic waste. The most common application has been the digestion of animal dung, agricultural, and food-industrial waste. This was studied by our department in our pilot farm of our Faculty. The 50-dairy cow, family sized model farm was built in the summer of 1991, as a result of a Dutch – Hungarian cooperation, on the property of the Faculty. The new pig farm, with 30 sows, and the new goat farm, with 100 nannies, was given to the Faculty on 25 April 2001. On the basis of livestock data, the annual dung production and the producible energy were determinate. The energy was calculated by biogas production coefficients in literature.

Enhancement of anaerobic digestibility of lipids and optimization of biogas production by implementing emulsification as pre-treatment method

2020 ◽  
Author(s):  
Αλέξανδρος Ευταξίας
Keyword(s):  
Biogas Production ◽  
Contact Process ◽  
Treatment Method ◽  
Pre Treatment ◽  
Anaerobic Digestibility

Στόχος της παρούσας διδακτορικής διατριβής υπήρξε η ανάπτυξη ολοκληρωμένης διεργασίας αναερόβιας χώνευσης με υψηλή περιεκτικότητα σε λίπη μέσω της διερεύνησης και βελτιστοποίησης (α) κατάλληλης διεργασίας προ-επεξεργασίας λιπών/ελαίων για περιορισμό των λειτουργικό προβλημάτων και (β) κατάλληλου τύπου αντιδραστήρα για την διαχείριση αποβλήτων υψηλής περιεκτικότητας σε λίπη. Τα λιπίδια χαρακτηρίζονται από χαμηλή διαλυτότητα και πυκνότητα, με αποτέλεσμα να παρουσιάζουν χαμηλή διαθεσιμότητα καθώς επιπλέουν στην επιφάνεια του αντιδραστήρα. Η αναερόβια χώνευση λιπιδίων μπορεί να οδηγήσει σε λειτουργικές αστάθειες όπως διάλυση των κόκκων/ φλόκων της αναερόβιας βιομάζας, αφρισμό και επίπλευση της ιλύος, παρεμπόδιση και τοξικότητα έως και πλήρη κατάρρευση των διεργασιών παραγωγής βιοαερίου. Με στόχο τον περιορισμό των παραπάνω προβλημάτων έχουν εφαρμοστεί διάφορες μέθοδοι προ-επεξεργασίας των λιπιδίων οι οποίες στοχεύουν σε αύξηση της βιοδιαθεσιμότητας αυτών και σε άρση των περιορισμών στη μεταφορά μάζας. Τέτοιες μέθοδοι είναι η σαπωνοποίηση, η ενζυματική υδρόλυση και η γαλακτωματοποίηση. Η τελευταία μέθοδος προ-επεξεργασίας, οδηγεί στην μείωση του μεγέθους των λιπιδίων σε επίπεδα του μικρομέτρου αυξάνοντας έτσι σημαντικά τη διεπιφάνεια νερού-ελαίου και περιορίζοντας την επίπλευση ελεύθερων λιπών εντός του χωνευτή. Ως μειονεκτήματα της μεθόδου είναι ότι απαιτούνται σημαντικά ποσά ενέργειας καθώς και η προσθήκη γαλακτωματοποιητών. Σύμφωνα με τα παραπάνω η αναερόβια χώνευση λιπιδίων υπόκειται τόσο σε θερμοδυναμικούς περιορισμούς των βιολογικών διεργασιών όσο και τεχνικά και λειτουργικά προβλήματα της εγκατάστασης. Για τους παραπάνω λόγους η προσθήκη λιπιδίων σε μονάδες βιοαερίου πλήρους κλίμακας δεν πραγματοποιείται είτε είναι περιορισμένη. Μελετήθηκε η γαλακτωματοποίηση ως μέθοδος προ-επεξεργασίας για την αναερόβια χώνευση διαφορετικών LCFAs σε μεσόφιλες συνθήκες σε αντιδραστήρες ημι-συνεχούς λειτουργίας. Έγινε εφαρμογή του μοντέλου (ADM1) στα πειραματικά δεδομένα το οποίο συνέβαλε στην ποσοτικοποίηση των κινητικών παραμέτρων αποικοδόμησης του ελαϊκού οξέως ως συνάρτηση της εφαρμοζόμενης προ-επεξεργασίας. Εξετάστηκε ο περιοριστικός ρόλος των ιχνοστοιχείων στην αναερόβια αποικοδομησιμότητα γαλακτωματοποιημένου ζωικού λίπους. Τα πειράματα έλαβαν χώρα σε αντιδραστήρα πλήρους ανάμιξης (CSTR) με ανακυκλοφορία της βιομάζας (contact process). Δόθηκε έμφαση στην διερεύνηση και βελτιστοποίηση ενός κατάλληλου τύπου αντιδραστήρα (CSTR και PFR) για την συν-χώνευση αγροτοβιομηχανικών αποβλήτων με λίπη και έλαια. Τέλος πραγματοποιήθηκε τεχνοοικονομική ανάλυση ως προς την δυνατότητα αναβάθμισης μιας υφιστάμενης μονάδας αναερόβιας χώνευσης από τα 500 στα 1000 kW, μέσω της προσθήκης λιπιδίων σε ποσοστό 1% v/v. Η παρούσα διδακτορική διατριβή κατέληξε στα ακόλουθα συμπεράσματα: •Η γαλακτωματοποίηση ως μέθοδος προ-επεξεργασίας διαδραματίζει σημαντικό ρόλο στην αναερόβια χώνευση λιπιδίων. •Τα ιχνοστοιχεία διαδραματίζουν σημαντικό ρόλο στην αναερόβια χώνευση αποβλήτων με υψηλή περιεκτικότητα σε λίπη. •Το μοντέλο ADM1 είναι κατάλληλο για την προσομοίωση των διεργασιών αναερόβιας χώνευση σε όλες τις περιπτώσεις. •Το περιοριστικό βήμα ως προς την αναερόβια χώνευση των διαφορετικών LCFAs που μελετήθηκαν ήταν η αποικοδόμηση του στεαρικού οξέως.

scholarly journals Effective Pre-Treatments for Enhancement of Biodegradation of Agricultural Lignocellulosic Wastes in Anaerobic Digestion – A Review

2020 ◽  
Vol 23 (3) ◽  
pp. 105-110
Author(s):  
Fatemeh Rahimi-Ajdadi ◽  
Masoomeh Esmaili
Keyword(s):  
Anaerobic Digestion ◽  
Crop Residues ◽  
Biogas Production ◽  
Biofuel Production ◽  
Agricultural Crop ◽  
Advantages And Disadvantages ◽  
Lignocellulosic Wastes ◽  
Pre Treatment ◽  
Anaerobic Digestibility ◽  
Emission Of Greenhouse Gases

AbstractAgricultural crop residues like stems, straws and leaves are valuable resources for biofuel production, especially methane, due to anaerobic digestion. Biogas from agricultural lignocellulosic wastes is capable of attaining sustainable energy yields without environmental pollution. Farmers in many developing countries burn these wastes throughout their fields, imposing environmental hazard due to emission of greenhouse gases. The main problem in this field is the recalcitrance of the agricultural lignocellulose waste that limits its enzymatic degradation and hydrolysis efficiency and consequently decreases biogas production. Therefore, efficient pre-treatments prior to anaerobic digestion are essential. Various pre-treatment methods are used for increasing the anaerobic digestibility of lignocellulose biomass, such as physical (mechanical, thermal, etc.), chemical, biological and combined pre-treatments. This paper reviews different pre-treatments used in anaerobic digestion for the agricultural lignocellulosic wastes and explains the advantages and disadvantages of each. The most frequently used pre-treatments for main agricultural wastes in process of biogas production are also introduced.

scholarly journals BIOGAS POTENTIAL OF DIGESTATE AFTER FERMENTATION OF SIDA HERMAPHRODITA SILAGE

2018 ◽  
Author(s):  
Paulina RUSANOWSKA ◽  
Magda DUDEK ◽  
Marcin ZIELIŃSKI ◽  
Marcin DĘBOWSKI
Keyword(s):  
Organic Compounds ◽  
Retention Time ◽  
Hydraulic Retention Time ◽  
Biogas Production ◽  
Complex Structure ◽  
Yield Potential ◽  
High Yield ◽  
Two Samples ◽  
Pre Treatment ◽  
High Yield Potential

Lignocellulosic biomass is one of the most widely used substrate in methane digestion. Among plants with a high yield potential, Sida hermaphrodita is particularly noteworthy, due to Sida can be grown on low quality soils and its utilization for energy purposes is not competitive with food crops. Methane fermentation of biomass with such a complex structure usually requires application of pre-treatment methods for efficient utilization of its cellulose and hemicellulose. It is economically justified to control of digestate if substrate was efficiently used. The study aimed to measure biogas potential of digestate after fermentation of Sida hermaphrodita silage. The post-fermentation of two samples of digestate from the reactors operated at organic compounds loading 2 kg/(m3∙d) – S1 and 3 kg/(m3∙d) – S2 was performed. Hydraulic retention time in these reactors was 50 d and 33 d, respectively. Biogas potential of fermented sludge was measured with the use of AMPTS II (Bioprocess control). Biogas production was 0.012 L/g TS and 0.031 L/g TS from digestate’s S1 and S2, respectively. The methane content in biogas was 15% from digestate S1 and 50% from digestate S2. The obtained results suggest that digestate from reactor with organic compounds loading of 3 kg/(m3∙d) still has high biogas potential, and hydraulic retention time in this reactor should be prolonged.

Swine manure biogas production improvement using pre-treatment strategies: lab-scale studies and full-scale application

2021 ◽  
pp. 100716
Author(s):  
Deisi Cristina Tápparo ◽  
Daniela Cândido ◽  
Ricardo Luis Radis Steinmetz ◽  
Christian Etzkorn ◽  
André Cestonaro do Amaral ◽  
...  
Keyword(s):  
Biogas Production ◽  
Swine Manure ◽  
Treatment Strategies ◽  
Full Scale ◽  
Production Improvement ◽  
Pre Treatment

scholarly journals The McDonaldization of Academic Libraries?

2015 ◽  
Vol 76 (3) ◽  
pp. 339-352 ◽  
Author(s):  
Brian Quinn
Keyword(s):  
Academic Libraries ◽  
Fast Food ◽  
Food Industry ◽  
Fast Food Industry ◽  
University Of Maryland ◽  
The University

George Ritzer, a sociologist at the University of Maryland, has proposed an influential thesis that suggests that many aspects of the fast food industry are making their way into other areas of society. This article explores whether his thesis, known as the McDonaldization thesis, is applicable to academic libraries. Specifically, it seeks to determine to what extent academic libraries may be considered McDonaldized, and if so, what effect McDonaldization may be having on them. It also investigates some possible alternatives to McDonaldization, and their implications for academic libraries.

scholarly journals Microwave Heating as an Alternative Quarantine Method for Disinfestation of Stored Food Grains

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Ipsita Das ◽  
Girish Kumar ◽  
Narendra G. Shah
Keyword(s):  
Microwave Treatment ◽  
Environmental Concerns ◽  
Selective Heating ◽  
Food Grains ◽  
Hot Air ◽  
Quality Retention ◽  
The World ◽  
Hot Air Treatment ◽  
Environmentally Sound ◽  
Free Environment

Insects and pests constitute a major threat to food supplies all over the world. Some estimates put the loss of food grains because of infestation to about 40% of the world production. Contemporary disinfestation methods are chemical fumigation, ionizing radiation, controlled atmosphere, conventional hot air treatment, and dielectric heating, that is, radio frequency and microwave energy, and so forth. Though chemical fumigation is being used extensively in stored food grains, regulatory issues, insect resistance, and environmental concerns demand technically effective and environmentally sound quarantine methods. Recent studies have indicated that microwave treatment is a potential means of replacing other techniques because of selective heating, pollution free environment, equivalent or better quality retention, energy minimization, and so forth. The current paper reviews the recent advances in Microwave (MW) disinfestation of stored food products and its principle and experimental results from previous studies in order to establish the usefulness of this technology.

Alkali pre-treatment of Sorghum Moench for biogas production

2013 ◽  
Vol 67 (9) ◽  
Author(s):  
Karina Michalska ◽  
Stanisław Ledakowicz
Keyword(s):  
Anaerobic Digestion ◽  
Chemical Oxygen Demand ◽  
Volatile Fatty Acids ◽  
Biogas Production ◽  
Oxygen Demand ◽  
Total Phenolic ◽  
Methane Generation ◽  
Pre Treatment ◽  
Alkali Hydrolysis ◽  
Almost All

AbstractThis work studies the influence of the alkali pre-treatment of Sorghum Moench — a representative of energy crops used in biogas production. Solutions containing various concentrations of sodium hydroxide were used to achieve the highest degradation of lignocellulosic structures. The results obtained after chemical pre-treatment indicate that the use of NaOH leads to the removal of almost all lignin (over 99 % in the case of 5 mass % NaOH) from the biomass, which is a prerequisite for efficient anaerobic digestion. Several parameters, such as chemical oxygen demand, total organic carbon, total phenolic content, volatile fatty acids, and general nitrogen were determined in the hydrolysates thus obtained in order to define the most favourable conditions. The best results were obtained for the Sorghum treated with 5 mass % NaOH at 121°C for 30 min The hydrolysate thus achieved consisted of high total phenolic compounds concentration (ca. 4.7 g L−1) and chemical oxygen demand value (ca. 45 g L−1). Although single alkali hydrolysis causes total degradation of glucose, a combined chemical and enzymatic pre-treatment of Sorghum leads to the release of large amounts of this monosaccharide into the supernatant. This indicates that alkali pre-treatment does not lead to complete cellulose destruction. The high degradation of lignin structure in the first step of the pre-treatment rendered the remainder of the biomass available for enzymatic action. A comparison of the efficiency of biogas production from untreated Sorghum and Sorghum treated with the use of NaOH and enzymes shows that chemical hydrolysis improves the anaerobic digestion effectiveness and the combined pre-treatment could have great potential for methane generation.

scholarly journals Optimisation of Protein Recovery from Arthrospira platensis by Ultrasound-Assisted Isoelectric Solubilisation/Precipitation

Processes ◽  
2020 ◽  
Vol 8 (12) ◽  
pp. 1586
Author(s):  
Ana Sánchez-Zurano ◽  
Ainoa Morillas-España ◽  
Cynthia Victoria González-López ◽  
Tomás Lafarga
Keyword(s):  
Food Industry ◽  
Functional Foods ◽  
Osmotic Shock ◽  
Arthrospira Platensis ◽  
Extraction Time ◽  
Protein Recovery ◽  
Solvent Ratio ◽  
Total Proteins ◽  
Cell Wall Disruption ◽  
Pre Treatment

A response surface methodology was used to optimise the solubilisation and precipitation of proteins from the cyanobacterium Arthrospira platensis. Two separate experiments were designed and conducted in a sequential manner. Protein solubilisation was affected by pH, extraction time, and biomass to solvent ratio (p < 0.001). Although spray-drying and the osmotic shock suffered when resuspending the dried biomass into distilled water led to a certain degree of cell wall disruption, the amount of protein that could be solubilised without an additional disruption step was in the range 30–60%. Sequential extractions improved protein solubilisation by less than 5%. For this reason, a pre-treatment based on sonication (400 W, 24 kHz, 2 min) had to be used, allowing the solubilisation of 96.2% of total proteins. Protein precipitation was affected by both pH and extraction time (p < 0.001). The optimised precipitation conditions, which were pH 3.89 over 45 min, led to a protein recovery of 75.2%. The protein content of the extract was close to 80%, which could be further increased by using different purification steps. The proteins extracted could be used in the food industry as technofunctional ingredients or as a source of bioactive hydrolysates and peptides for functional foods and nutraceuticals.

Microwave-Assisted Grinding of Bolkardag (Nigde, Turkey) Gold Ore and Enhanced Cyanide Leachability

2018 ◽  
Vol 115 (5) ◽  
pp. 508 ◽  
Author(s):  
Cemaliye Seflek ◽  
Oktay Bayat
Keyword(s):  
Particle Size ◽  
Power Level ◽  
Microwave Treatment ◽  
Cyanide Leaching ◽  
Gold Ore ◽  
Work Index ◽  
Significant Difference ◽  
Bond Work Index ◽  
Pre Treatment ◽  
Silver Extraction

This experimental work aims at studying the effect of particle size on the microwave pre-treatment for the grindability of Bolkardag (Nigde, Turkey) gold ore for cyanide leaching. Three different particle size batches (−8 + 4.7 mm, −4.75 + 2 mm and −2 + 1 mm) were used for microwave treatment. Each sub-samples were exposed to four different power levels of microwave energy (0.09, 0.18, 0.36 and 0.6 kW) at exposure times of 5, 10, 15 and 30 minutes and then grindability characteristic of the treated samples were investigated with Berry and Bruce comparative grindability method. It was clearly seen that increasing power level and exposure time caused a reduction in comparative Bond Work index. A maximum reduction in Bond Work index (73.54%) was achieved by 0.6 kW at 30 minutes of microwave treatment. Compared to the untreated sample’s results, gold and silver extraction rates increased, using microwave-treated samples, about 7% and 9% after 77 hours cyanide leaching, respectively. Additionally, the hydrated lime added samples (after 0.6 kW at 30 minutes of microwave treatment) were used in the cyanide leaching tests to determine the possible effect. It was observed that there was no significant difference on leaching extraction rates using lime free or lime added samples. Applying microwave pre-treatment before cyanide leaching, the gold and silver extraction rates could be increased and also the cost of communition could be reduced due to easier breakage of the ore due to a significant decrease in Bond Work index.

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