Pretreatment Of Raw Material Research Articles

RESEARCH AND ANALYSIS OF DRIED KISHMISH AND RAISINS FROM GRAPES OF SOUTH KAZAKHSTAN

Dried fruits, including raisins, are of particular interest in nutritional studies due to its uniquechemical composition and natural qualities, which make raisins an attractive source of nutrients. Research andanalysis of kishmish and dried raisins was performed in the department Food Engineering of M. Auezov SKSU.Dried fruits were prepared by scientifically justified and developed technology of drying fruits to obtain domesticenvironmentally friendly dried grapes by infrared irradiation after pre-treatment of raw materials without the use ofchemical reagents.From this study, it can be concluded that the kishmish and raisins obtained from grapes varieties “Kishmishblack”, “Bulls-eye”, grown in South Kazakhstan region contain sufficient amount of sucrose (5.17 and 4.75respectively). Given samples also show high contents ofpotassium (17.98 and 33.02 respectively), calcium (1.19 and2.07 respectively), phosphorus (1.41and 4.47 respectively), but iron contents is much less (0.21and 0.27 respectively)than usually.Consumers and stakeholdersmay get benefits by production and realization of suggested kishmish and raisins asregional brands of Kazakhstan or products with geographical indications (GI).In the future it is necessary to carry out a lot of work on branding the products offered by the authors, providedthat it will satisfy the following values, such as technological novelty, rarity and uniqueness of the product,environmental friendliness of the manufacture and use of the product

Conversion of waste cooking oil into biogas: perspectives and limits.

Each year, large quantities of waste cooking oils are produced worldwide which are currently reused mainly for biodiesel production. Since lipids have a very high potential for biomethanation, the production of biogas is a possible alternative for the recycling of edible used oils. The digestion of fats is hindered mainly by their hydrophobicity, which implies a biphasic system with problems of floating and foaming of the oily materials, and by the accumulation of long-chain fatty acids, which are toxic to microbial consortia. The objectives of this review were to highlight the recycling potential of waste cooking oil to biogas production and to facilitate the application of the technology by identifying solutions to overcome biological and engineering limits to its diffusion. Particular attention was paid to the microbial populations involved, to the process factors whose control is important to improve the digestion of fats such as lipid concentration, pH, temperature, and agitation, and to technological solutions whose application also aims to improve digestion, such as pretreatment of raw materials and co-digestion of fats with other feedstocks. The state of the art in reactor designs suitable for lipid digestion was also examined.

Получение и выделение кремнийсодержащих продуктов из рисовой шелухи

To isolate silicon-containing products from plant materials, the reaction of interaction of rice husks with triethanolamine and ethylene glycol have been investigated. The effect of pretreatment of raw materials and the reaction conditions on the yield of soluble products containing silicon has been studied. It has been shown that the highest enrichment of rice husks with silicon occurs upon its treatment with concentrated hydrochloric acid and the Schweitzer's reagent. The highest degree of silicon extraction (69%) was achieved at using native rice husks and vanadyl acetylacetonate as a catalyst. The resulting solution contained silicon in the form of silatrane fragments. In order to isolate a silicon-containing product from the ethylene glycol solution, which would have the prospect of practical use and the maximum silicon yield, the heterofunctional polycondensation method was applied. It has appeared to be possible to isolate solid products using acetylacetonates of trivalent and tetravalent metals, which formed metal siloxanes. The structure of the obtained compounds has been confirmed by the element and X-ray diffraction analysis, as well as by the IR spectroscopy. When using rice husk chaffs as a silicon source, the product of the reaction with ethylene glycol and triethanolamine has appeared to be an irregular copolymer comprising amorphous silicon dioxide fragments and cyclic fragments similar in structure to that of silatranes. The application of metal acetylacetonates has made it possible to isolate silicon derivatives in the form of organometallic siloxanes. Тhe yield of metalsiloxanes increased in the sequence Zr < Fe < Al. Apparently, this was due to formation of lattice structures in the case of trivalent aluminum and iron, while zirconium had two remaining acetylacetonate groups and, in this case, its functionality was lower than for trivalent metals, which was confirmed by the spectral data.

Exploitation of Wheat Straw Biorefinery Side Streams as Sustainable Substrates for Microorganisms: A Feasibility Study

Lignocellulosic agricultural side products, like wheat straw, are widely seen as an important contribution to a future sustainable economy. However, optimization of biorefinery processes and exploitation of all side streams are crucial for an economically viable biorefinery. Pretreatment of lignocellulosic raw material, which is necessary for further processing steps, can generate low-value side streams. In this feasibility study, side streams from a liquid hot water (LHW) pretreatment of wheat straw were utilized for the production of polyhydroxybutyrate (PHB) and highly valuable tetraether lipids (TELs). Additional value created by these products can benefit the biorefinery’s economic operation. The utilized wheat straw was pretreated at 120 °C and 170 °C for up to two hours in laboratory and lab scale. The resulting side stream consists mainly of carbohydrates from hemicelluloses and fermentation inhibitors such as acetic acid. In order to achieve a successful production of both products, an acetic acid separation via distillation was necessary. Subsequently, the acetic acid fraction was utilized for the PHB production using cyanobacteria. The carbohydrate-rich fraction was applied in the cultivation of Sulfolobus acidocaldarius and resulted in the successful production of TELs. Both fractions achieved better fermentation yields compared to their corresponding reference media.

Alkaline Pre-Treatment of Gelidium Latifolium and Caulerpa Racemosa for Bioethanol Production

Raw material pre-treatment becomes an important step in the bioetanol production from macroalgae. It’s help to breakdown sulfated groups and lignin, facilitate the hydrolysis process to increase reducing sugars. Gelidium latifolium and Caulerpa racemosa are red and green algae which used for bioethanol production in this study. The carbohydrate content was 23.81% and 30.54% respectively. The study aims to evaluate the effect of alkaline pre-treatment to the chemical characteristics of macroalgae, productivity of sugar and bioethanol. The alkaline used was sodium hydroxide (NaOH) with a concentration of 0.05 and 0.1 N, soaking time for 3 days at room temperature. From the result, it was known that water and alkaline pre-treatment increased cellulose content for both macroalgae, as well as yield of reducing sugars. The highest reducing sugar for G. latifolium was 5.26% w/v obtained from 0.1 N NaOH pre-treatment. While for C. racemosa it was 7.67% w/v obtained from the one which submerged on water. G. latifolium treated with 0.05 N NaOH has the highest ethanol content of 6.3 ml/L with 21.94% fermentation efficiency and 37.30% substrate efficiency. On the other hand, the highest ethanol production for C. racemosa obtained from water immersion of 7 ml/L with 17.26% fermentation efficiency and 15.41% substrate efficiency.

Metal triflates are tunable acidic catalysts for high yielding conversion of cellulosic biomass into ethyl levulinate

Metal triflates and their mixtures with Brønsted acids are excellent catalysts for the selective and high yielding transformation of microcrystalline cellulose into ethyl levulinate, in ethanol, producing synergistic catalyst effects in some instances. The pretreatment of raw and unrefined cellulosic materials with a deep eutectic solvent enables similarly excellent catalysed conversion thereof into ethyl levulinate in superb yield (up to 75%) and selectivity (up to 88%). When using fermentation-derived ethanol, the product possesses 100% renewable content.

Effect of the black chokeberry (Aronia melanocarpa (Michx.) Elliott) juice acquisition method on the content of polyphenols and antioxidant activity.

The primary objective of the study was to determine the effect of process conditions on extraction efficiency and the total amount of released polyphenols and antioxidant activity (AA) in black chokeberry juice. The study samples were fruits of black chokeberry (Aronia melanocarpa (Michx.) Elliott) cv. Galicjanka. In the study, two kinds of presses—piston press and twin gear juice extractor—were used, and two raw material pretreatment methods—freezing and thawing and enzymatic liquefaction—were applied. The study showed that pressing efficiency depends on the design of press and the nature of pretreatment. The highest pressing efficiency was obtained using the twin gear juice extractor. Enzymatic liquefaction of shredded fruits significantly increased the efficiency of pressing by the piston press. The type of press and the pretreatment method used had an effect on the quality traits of the extracted juices. The highest content of soluble solids was obtained for fruits not subjected to any pretreatment and pressed using the twin gear press. The highest total phenolic content was obtained in juice extracted using the piston press from shredded fruits subjected to enzymatic treatment at 45°C. A higher total phenolic content was also a characteristic of juice obtained from fruits not subjected to any pretreatment and extracted using the twin gear press. The capacity of the black chokeberry juices for free radical quenching oscillated around the level of approximately 90%. The study showed that the application of suitable processing methods is necessary for the acquisition of products with desirable quality traits.

Biodegradation of lignin of Bambusa nutans by the isolate Inonotus pachyphloeus JP-1

A delignification pretreatment of raw materials for paper and pulp industry is important as traditional chemical degradation is hazardous to health and the environment. The aim of the present study was to identify potential laccase producing fungi with special attention on their feasibility for the degradation of lignin of Bambusa nutans. Among 155 fungal isolates from bamboo stacking area of a paper mill, Inonotus pachyphloeus JP-1, characterized by morphological and internal transcribed spacer sequence analysis was found to have best potential for it. Laccase enzyme activity of the isolate JP-1 was studied for 72–288 h, and the highest activity of 666.8 nkat/ml was recorded at 144 h using 1 mM of CuSO4 as an inducer. B. nutans samples pretreated with the isolate recorded higher lignin degradation (45.80%) with minimum loss of cellulose content (2.24%) after 30 days of treatment. Furthermore, scanning electron microscopy, X-ray diffractometery and fourier transform infrared spectra of untreated and treated samples confirmed the effect of pretreatment on the cellular structure of B. nutans. This is the first report on I. pachyphloeus as a potent lignin degrader which can be further exploited for the development of clean technologies for paper and pulp industries.

Generation of High Quality Biogenic Silica by Combustion of Rice Husk and Rice Straw Combined with Pre- and Post-Treatment Strategies—A Review

Utilization of biomass either as a renewable energy source or for the generation of biogenic materials has received considerable interest during the past years. In the case of rice husk (RH) and rice straw (RS) with high silica contents in the fuel ash, these approaches can be combined to produce high-grade biogenic silica with purities >98 wt % from combustion residues. The overall process can be considered nearly neutral in terms of CO2 emission and global warming, but it can also address disposal challenges of rice husk and rice straw. For the resulting biogenic silica, several advanced application opportunities exist, e.g., as adsorbents, catalysts, drug delivery systems, etc. This article provides a comprehensive literature review on rice husk and rice straw combustion as well as applied strategies for raw material pre-treatment and/or post-treatment of resulting ashes to obtain high quality biogenic silica. Purity of up to 97.2 wt % SiO2 can be reached by combustion of untreated material. With appropriate fuel pre-treatment and ash post-treatment, biogenic silica with purity up to 99.7 wt % can be achieved. Studies were performed almost exclusively at a laboratory scale.

Biomass Pellets from Oil Palm Empty Fruit Bunches (OP-EFB)

Oil Palm growths in Indonesia are getting higher every year. Oil palm plantationproduced various waste, including oil palm empty fruit bunches (OP-EFB). 95 % Indonesia energy demand still provided by the fossil fuel and only 5 % provided by renewable energy, which provide opportunity of OP-EFB biomass pellets to be utilized as alternative resource. The research of biomass still low, especially research of OP-EFB biomass pellets. Therefore, the research objectives were to determine the production process of OP-EFB and to define the most effective binder and binder ratio for the biomass pellets. This research experiments consist of shredding, chopping, drying, grinding, and sieving as raw material pretreatment. Also, varying the binder and binder concentration of the mixture between raw materials was the part of this thesis research. The binders used in this thesis research are PVAC paste and tapioca based paste with 4 variations of concentration. The analyses of the biomass pellets characteristic are density,compressive strength, proximate analysis (moisture, ash, volatile matter, and fixed carbon), calorific value, combustion rate, and gas chromatographic & mass spectroscopy (GCMS). The result shows that OP-EFB biomass pellets are qualified to be considered as biomass pellets. The most effective OP-EFB biomass pellets is biomass pellets with 10% tapioca binder concentration.

Термопластическая экструзия в процессах пищевой биотехнологии

The development of food biotechnology involves the improvement and optimisation of all stages of the technological process – from the pretreatment of raw materials to the stages of biocatalysis, fermentation and derivation of finished product. Based on relevant scientific sources, a review of the prospects for the integration of thermoplastic extrusion into food biotechnological production, which has a number of technological and economic advantages, is carried out. It is shown that extrusion as a stage of pre-treatment of raw materials increases the degree of solubility, allowing further hydrolysis of starch, protein and non-starch polysaccharides, with a corresponding increase in the yield of bioconversion products. In distillation processes, the use of extruded starch-containing raw materials can become a factor in increased ethanol yield and a reduction in the formation of minor metabolites of fermentation; in brewing, it allows the expanded use of unmalted materials in the preparation of wort; while, in the deep cultivation of microorganisms (enzyme producers), it can be a factor in the increased concentration of the medium and consequent synthesis of enzymes. Positive results for the derivation of nutrient media on extruded raw materials for microbiological production of L (+) lactic acid, production of starter cultures and multicomponent fermented milk-containing products are reported. A combination of extrusion and biocatalysis in the extruder chamber allows maltodextrins to be obtained having a dextrose equivalent of up to 10 units. In addition to the processing of starchy substrates by extrusion in combination with biocatalytic treatment, a deep modification of biopolymers materials having a high protein and dietary fibre content, for example, hydrolysis with heat-stable antigenic properties of the protein fractions of glycinin and conglycinin in soybean meal, increases the functionality of the bran content of water-soluble araboxylans in specialised extruded products. The main factors affecting the degree of processing of raw materials and the quality of the target products are moisture content and extrusion temperature, as well as dosage of enzyme preparations. The possibilities of combining the processes of extrusion and biocatalysis in one reactor system or directly in the extruder chamber are described. These can significantly increase the concentration of processed biotechnological media, simplify the hardware and process composition of production lines, at the same time as increasing production capacity and energy efficiency.

Research Progress of Application of Steam Explosion Technology in Pretreatment of Food Raw Materials

Steam explosion technology is an emerging raw material pretreatment method, green and efficient. It does not need to add chemical reagents, but can change the structure of food raw materials and improve the yield of effective components by high temperature and high pressure.This article reviewed the recent advances in the application of steam explosion technology in pretreatment of food raw material, including its effects on the nutritional components, functional ingredients and physical and chemical properties of food raw materials, and provided a valuable reference for the wider application of the technology in future food processing.

WORLD AND DOMESTIC EXPERIENCE OF BIOETHANOL PRODUCTION

The paper presents an overview of bioetanol production technologies. It is noted that world fuel ethanol production in 2017 amounted to more than 27,000 million gallons (80 million tons). Eight countries, namely the USA, Brazil, the EU, China, Canada, Thailand, Argentina, India, together produce about 98% of bioethanol. In Ukraine, the volume of bioethanol production by alcoholic factories in recent years has been gradually increasing and amounted to 2,992.8 ths. dal in 2017. The production of ethanol as an additive to gasoline, with regard to the raw materials used, as well as the corresponding technologies, is historically divided into three generations. The first generation of biofuels produced from food crops rich in sugar or starch is currently dominant.
 Production of advanced biofuels from non-food crop feedstocks is limited. Output is anticipated to remain modest in the short term, as progress is needed to improve technology readiness. The main stages of bioethanol production from lignocellulosic raw materials are pre-treatment, enzymatic hydrolysis and fermentation. The pre-treatment process aims to reduce of sizes of raw material particles, provision of the components exposure (hemicellulose, cellulose, starch), provision of better access for the enzymes (in fermentative hydrolysis) to the surface of raw materials, and reduction of crystallinity degree of the cellulose matrix. The pre-treatment process is a major cost component of the overall process. The pre-treatment process is highly recommended as it gives subsequent or direct yield of the fermentable sugars, prevents premature degradation of the yielded sugars, prevents inhibitors formation prior hydrolysis and fermentation, lowers the processing cost, and lowers the demand of conventional energy in general. From the perspective of efficiency, promising methods of pre-treatment of lignocellulosic raw materials to hydrolysis are combined methods combining mechanical, chemical and physical mechanisms of influence on raw materials. One method that combines several physical effects on a treated substance is the discrete-pulsed energy input (DPIE) method. The DPIE method can be applied in the pre- treatment of lignocellulosic raw material in the technology bioethanol production for intensifying the process and reducing energy consumption. Ref. 15, Fig. 2.

A Nano-Ink for gel pens based on scalable CNC preparation

Recently, gel pens have been the most popular writing instrument all over the world because of their excellent writing performance. However, the gel ink of the pen is difficult to manufacture because the composition of the ink is complicated with specific rheological properties and high-stability requirements. This is the first report of an easily manufactured Nano-Ink for gel pens that is based on cellulose nanocrystals (CNCs) grafted to reactive dyes. The obtained Nano-Ink exhibits proper rheological properties and writing performance when the concentration of CNCs in this ink is 5.96%. For the potential commercial application of this Nano-Ink, a method for large-scale production of CNCs is also developed in our laboratory, including pretreatment of raw material with sulfuric acid, purification of the treated cellulosic fiber with ammonium bicarbonate (AH-NH4HCO3), and then homogenization. In AH-NH4HCO3 method, the “ultrafine fibers” are retained in the presence of NH4HCO3 during centrifugation, and the added NH4HCO3 is removed by vacuum distillation. The final CNC yield after homogenization is above 90%, which is much higher than that in previous reports, when dissolving pulp as feedstock is treated with 58% sulfuric acid at 55 °C for 45 min. Therefore, the Nano-Ink based on CNCs is promisingly going to commercial production.

BIFUNCTIONAL SYNTHETIC BINDINGS AS ALTERNATIVE FOR THE BEZFORMALDEHYDE PRODUCTION OF WOOD PLATE MATERIALS

The paper presents the results of experiments on the production of wood board materials without the use of formaldehyde-containing resins. As the initial samples used sawdust of pine wood without and using cavitation pretreatment in a neutral medium. Bifunctional synthetic substances were selected as binders: phthalic and maleic acids and their anhydrides, glycols-ethylene glycol and butanediol-1,4, as well as equimolar two-component mixtures based on them with a concentration of 5-15%. The resulting presses were hot-formed at a temperature of 160 °C and a pressure of 10 MPa. As a result of the experiment, wood-based board materials of medium density with bending strength 11.0–46.0 MPa, water absorption for 24 hours – 1–115% and swelling in thickness over 24 hours – 3–100% are obtained. The most beneficial is the use of a 5% concentration of binders satisfying the standard. Cavitated pre-treatment of plant raw materials allows to increase the strength characteristics by 1.3 times. Samples with the best physicomechanical indexes are obtained when maleic acid and its anhydride are used as a binder and their mixtures with glycols. In IR spectroscopy it was determined that the main bonds forming the mesh structure of plate materials are ester ones.Thus, under the selected molding conditions, plate-free plate materials based on bifunctional synthetic binders with high environmental and physico-mechanical properties are obtained.

Subcritical butane extraction of oil and minor bioactive components from soybean germ: Determination of migration patterns and a kinetic model

AbstractFor the aim of determining the migration patterns and extraction kinetics of the oil and minor bioactive components during subcritical fluid extraction (SFE) process from soybean germ, the extraction efficiency was investigated at different temperature and time with butane as solvent. The results indicate that flaking treatment is beneficial to the release of soybean germ oil (SGO) and bioactive components. The chosen models (So and Macdonald's model for SGO, Baümler's model for bioactive components) were found to be in good agreement with the experimental data and could be used to explain the SGO and bioactive components migration during SFE process. Furthermore, the activation energy of phytosterols, tocopherols, and phospholipids were 13.42, 12.23, and 22.72 kJ/mol, respectively. In conclusion, high‐quality SGO that contain high levels of phytosterols (26.51 mg/g) and tocopherols (2.29 mg/g) and a lower content of phospholipids (26.68 mg/g) can be obtained with an extraction at 60 °C for 45 min.Practical applicationsIn this study the effects of pretreatment of SG, solid/liquid ratio, extraction temperature and time on the yields of SGO and minor bioactive components were investigated. Simultaneously, the migration patterns and kinetic models of SGO and minor bioactive components described the subcritical butane extraction process accurately. Therefore, the research provided a theoretical support for the pretreatment of raw materials and the parameters control of subcritical extraction of soybean germ oil. The study can guide the popularization and application of subcritical fluid extraction for soybean germ oil extraction effectively. At present, the technology is ready for technical transformation in Henan subcritical fluid extraction company.

Study of the сhemical composition of cranberry and the use of berries in food technology

We investigated the ingredient composition of fractions of phenolic compounds of cranberries gathered in Ukraine and its change depending on methods of fermentolysis in the production of juice. The studies showed that the use of complex action enzymes for pretreatment of raw material makes it possible to enrich finished product with physiologically active ingredients of raw material by adjusting the activity during fermentolysis of endo- and exo-enzymes. We established that we can expect the best results in the case of instantaneous warming of squash after enzymatic treatment. We determined that significant content of phenolic substances remains in the waste of juice production – in squash. The complex processing of cranberries with the use of cranberry juice in the technology of fruit sauces, as well as high-quality juice production, is offered in the technology of nonalcohol beverages and meat pastes. The use of cranberry juice in fruit sauces provides product with a pleasant color, prevents darkening of bananas during processing. The use of water-alcohol extracts produced from squash makes possible to avoid the use of artificial coloring agents in the production of nonalcohol beverages. The use of powder made of dried cranberry squash in the receipt of paste products increases moisture binding capacity of meat and the output of a finished product. The study shows that the use of cranberries for the production of food products will make it possible to enrich chemical composition, to compensate for the deviation in functional and technological properties of raw material and to introduce resource-saving technologies

Effect of raw materials pretreated by physical grinding method on the sintering ability and microwave dielectric properties of Li2MgTiO4 ceramics

Li2MgTiO4-1 (abbreviated as LMT-1) ceramics were synthesized via the solid state reaction method using the pretreated raw materials. The unpretreated raw materials were used in the preparation of Li2MgTiO4-2 (abbreviated as LMT-2) ceramics. The particle size of LMT-1 powders is smaller and more uniform than that of LMT-2 powders and the porosity of LMT-1 ceramics is lower than that of LMT-2 ceramics. The microwave dielectric properties of LMT-1 ceramics keep a relatively stable value at a wide sintering temperature range. The slight fluctuation of sintering temperature will lead to great changes in the microwave dielectric properties of LMT-2 ceramics. The pretreatment of raw materials enhances the sintering ability and broadens the sintering temperature range of the Li2MgTiO4 ceramics.

Nanopaper Properties and Adhesive Performance of Microfibrillated Cellulose from Different (Ligno-)Cellulosic Raw Materials.

The self-adhesive potential of nanocellulose from aqueous cellulosic suspensions is of interest with regard to a potential replacement of synthetic adhesives. In order to evaluate the performance of microfibrillated cellulose from different (ligno-)cellulosic raw materials for this purpose, softwood and hardwood powder were fibrillated and compared to sugar beet pulp as a representative non-wood cellulose resource, and conventional microfibrillated cellulose produced from bleached pulp. An alkali pre-treatment of woody and sugar beet raw materials enhanced the degree of fibrillation achieved, same as TEMPO-mediated oxidation of microfibrillated cellulose. Nanopapers produced from fibrillated material showed highly variable density and mechanical performance, demonstrating that properties may be tuned by the choice of raw material. While nanopaper strength was highest for TEMPO-oxidated microfibrillated cellulose, fibrillated untreated sugar beet pulp showed the best adhesive performance. Different microscopic methods (AFM, SEM, light microscopy) examined the interface between wood and fibrillated material, showing particular distinctions to commercial adhesives. It is proposed that fibrillated material suspensions, which achieve bond strength up to 60% of commercial urea-formaldehyde adhesive, may provide a viable solution to bio-based adhesives in certain applications where wet-strength is not an issue.

Extraction and purification of high added value compounds from by-products of the winemaking chain using alternative/nonconventional processes/technologies

ABSTRACTGrape byproducts are today considered as a cheap source of valuable compounds since existent technologies allow the recovery of target compounds and their recycling. The goal of the current article is to explore the different recovery stages used by both conventional and alternative techniques and processes. Alternative pre-treatments techniques reviewed are: ultrasounds, pulsed electric fields and high voltage discharges. In addition, nonconventional solvent extraction under high pressure, specifically, supercritical fluid extraction and subcritical water extraction are discussed. Finally alternative purification technologies, for example membrane processing were also examined. The intent is to describe the mechanisms involved by these alternative technologies and to summarize the work done on the improvement of the extraction process of phenolic compounds from winery by-products. With a focus on the developmental stage of each technology, highlighting the research need and challenges to be overcome for an industrial implementation of these unitary operations in the overall extraction process. A critical comparison of conventional and alternative techniques will be reviewed for ethe pre-treatment of raw material, the diffusion of polyphenols and the purification of these high added value compounds. This review intends to give the reader some key answers (costs, advantages, drawbacks) to help in the choice of alternative technologies for extraction purposes.