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This chapter presents the similarity laws and model-testing for heat flow in structures. Similarity laws can be obtained from a nondimensional form of the fundamental equations of a problem. Such equations have been used, especially in simple cases when general results were sought. If similarity laws could be found, it would be possible to calculate in a simple way the influence of changes in the scale, in the flight plan or in the thermal properties of the materials from the known temperature distribution of a certain case; or to give requirements for laboratory simulation of heating on the prototype or on models. The treatment is theoretical and refers to temperature problems only. For instance, no discussion is given as to whether model testing is practical, either for finding temperature distributions only, or for mechanical strength tests under elevated transient temperatures.

Since the original use of solar cells for electrical power generation in space, the state of the art in solar-cell arrays has experienced some significant advances. The solar cell itself has been improved in many ways. These improvements have increased silicon solar-cell efficiencies from roughly 5% to 11% in space sunlight. Material improvements have been made in silicon which have enhanced the resistance of silicon solar cells to particle radiation. The methods used to connect cells into modules as a building block for constructing large arrays have been improved also. New methods in the soldering of cells into modules have decreased the degradation of the cells resulting from handling and soldering. In addition, the successful fabrication of cells into modules has made possible the matching of cells by modules rather than by single cells. The methods used to mount the modules to the supporting structure have been improved by using better techniques and bonding agents. With the above advances, sun-oriented arrays have been built which approach 10 w/ft2 and 10 w/lb when operated in near Earth space (with no particle radiation damage). With further research and development, the watts per square foot, watts per pound, radiation resistance, and cost of solar-cell arrays may he optimized further.

A miniature accelerometer has been constructed which employs a fused-quartz torsion fiber suspension. The purpose was to demonstrate a small yet reasonably accurate component, and at the same time explore the possibilities of fused quartz in a specific application. The accelerometer is based on the well-known force-balance servo principle, and employs a photoelectric pickoff. The design and construction of the device are described. Variation in null offset of ±1/2 × 10-4 g was observed over a 130-day period; linearity error to 1 g of 3 × 10-5 g rms (1σ) was observed. It appears that the torsion fiber suspension can provide a stable support with unusually small uncertainty torques, which is extremely rugged and stable.

Reflective displays are also widely used in display applications calling for ultra-low power consumption, sunlight readability, flexibility, low cost etc ., such as electronic paper (e-paper). “Bistability” means a display can retain a still image without power consumption in two states (usually black and white). Several mainstream reflective display technologies including electrophoretic, electro-wetting etc . will be introduced in this chapter.

The microbial electrolysis cell (MEC) is a technologically promising solution in terms of energy recovery from organic matter with the participation of microorganisms. The idea of the process is to decompose organic matter by electrically active bacteria in an electrochemical cell under anaerobic conditions while simultaneously degrading organic matter. The product of the process is biohydrogen, and the substrate used to generate it is a biodegradable source of organic matter, including products of sludge fermentation. This process is a configuration of the electrolysis process and metabolism of microorganisms. The emergence of bioelectrochemistry systems is conditioned by the course of physical and chemical reactions as well as the biological phenomena occurring in the interfacial surface formed by microorganisms and electrodes. Chemical, physical, and biological transformations enable the microorganism the exchange of electrons with solid electrons. As stated in the literature, the limit of energy efficiency of the process is the acquisition of biohydrogen from the biodegradable organic matter dissolved in 60%–80%. The type of electrode as well as the time of modification affect the efficiency of the electrolysis process of the sludge. The advantage of the microbial electrolysis cell is generating the biohydrogen through naturally occurring bacterial consortia without the involvement of exogenous mediators, making this technology easier to conduct and promising in terms of electricity generation. Generated hydrogen is a clean and renewable energy source because its combustion does not cause greenhouse gas emissions. The hydrogen oxidation product is H2O vapors. The aim of this paper is to analyze the issues concerning the use of microbial electrolysis cells (MEC) that influence the course of sludge degradation in the aspect of obtaining energy in the form of hydrogen.

The energy production from biomass through thermochemical processes is a promising technology to reduce the negative environmental impact. This study evaluates the environmental effects of the use of different Mexican biomasses (castor husk, coffee pulp and Pinus sawdust) on the combustion and gasification processes applied to energy production. The objective was to carry out the environmental and economic analysis associated with the generation of 1 MJ of energy for three proposals to determine which biomass is better to use as a raw material, which process is more respectful with the environment and economically viable. The life cycle assessment analysis showed that the combustion process is less harmful to the environment than the gasification process. In addition, for the two thermochemical processes studied, it was observed that the equipment that most damaged the environment was the Rankine cycle due to the emissions released and the energy consumed. Therefore, the coffee pulp was identified as the biomass with the most negative impact for both processes and the Pinus sawdust as the one that least affects the environment. The energy production through combustion process is more economically viable than the gasification, but both processes can be considered highly competitive for the biomass valorization., La producción de energía a partir de biomasa mediante procesos termoquímicos es una tecnología prometedora para reducir el impacto ambiental negativo. Este estudio evalúa los efectos ambientales del uso de diferentes biomasas mexicanas (cascarilla de ricino, pulpa de café y aserrín de pino) en los procesos de combustión y gasificación aplicados a la producción de energía. El objetivo fue realizar el análisis ambiental y económico asociado a la generación de 1 MJ de energía para tres propuestas con el fin de determinar qué biomasa es mejor utilizar como materia prima, qué proceso es más respetuoso con el medio ambiente y económicamente viable. El análisis de la evaluación del ciclo de vida demostró que el proceso de combustión es menos perjudicial para el medio ambiente que el de gasificación. Además, para los dos procesos termoquímicos estudiados, se observó que el equipo que más perjudicaba al medio ambiente era el ciclo Rankine debido a las emisiones liberadas y a la energía consumida. Por lo tanto, se identificó a la pulpa de café como la biomasa con mayor impacto negativo para ambos procesos y al aserrín de pino como el que menos afecta al medio ambiente. La producción de energía mediante el proceso de combustión es más viable económicamente que la gasificación, pero ambos procesos pueden considerarse altamente competitivos para la valorización de la biomasa.

Pharmaceuticals and personal care products (PPCP) in water and wastewater have caused growing concerns because of their great diversity and potential toxicity to the environment and to human beings. Therefore, research has been conducted to develop highly permeable carbon nanotube (CNT) composite membranes for efficient PPCP removal from water. This paper intends to provide a brief review of scientific and technological progress made by the author and other research groups in the past 5 years. The effects of CNT properties, water quality conditions, and PPCP characteristics on PPCP filtration were scientifically evaluated and further interpreted based upon relevant PPCP-CNT interactions. The presence of humic substances (HS) was found to be a major inhibitive condition on PPCP removal due to the competitive adsorption effect. This adverse effect may be suppressed technically by utilizing precoagulation to effectively remove HS from the raw water. Moreover, the thermal method effectively regenerated the adsorption capacity of CNTs for PPCPs, enabling repeated use of CNTs for membrane filtration. Despite the aforementioned promising progress, future research is warranted to advance this field by: (1) obtaining nanoscale understanding of the filtration process, and (2) evaluating the applicability of CNT membranes to longer-term, larger-scale water treatment practices.

Algae have been extensively explored for the production of useful bioactive compounds and biofuels. The photosynthesis-mediated conversion of carbon dioxide into biochemicals for the synthesis of biofuels, food, and highly valuable bioactive compounds are the drivers of the escalating interest in algae. Even though algae possess some advantages over other biofuel resources, the high cost involved in algal processing continues to be a challenge to commercial-scale development. Large-scale dewatering and drying of algal cultures for biomass generation involve high operation costs, resulting in significant challenges to the development of commercially viable production technologies. Centrifugation, flocculation, filtration, gravity sedimentation, flotation, and electrophoresis techniques are the conventional dewatering methods widely used. Similarly, solar, convective, spray-, and freeze-drying are the conventional methods used to dry algal cultures. Each method has specific pros and cons, requiring proper operational optimization and management to achieve improved dewatering and drying outcomes. Emerging methods such as bio-flocculation, membrane separation based dewatering techniques, and roller/drum and fluidized-bed based drying techniques provide further opportunities for integrated dewatering and drying technologies to improve efficiency and economics. This chapter discusses various dewatering and drying technologies of algal cultures along with their merits and demerits and makes proposals for enhanced dewatering and drying technologies for commercial applications.

Producción Científica, Microalgal-bacterial consortium can be used to upgrade biogas by removing CO2 and H2S. Photosynthetic biogas upgrading requires harvesting microalgal-bacterial biomass in order to use the biomass-free cultivation medium as scrubbing liquid in the absorption column. In this study, the efficiency of different flocculants (Zetag 8125, cationically modified cellulose nanocrystals, Tanfloc, chitosan, and FeCl3) to harvest microalgal-bacterial biomass used for biogas upgrading in alkaline medium (inorganic carbon concentration up to 1800 mg L−1 and a pH ~10) was evaluated. Zetag and cationic cellulose nanocrystals resulted in maximum flocculation efficiencies of 95% (optimal dose 30 mg g−1) and 93% (optimal dose 20 mg g−1), respectively. Low flocculation was observed with other flocculants at doses as high as 200 mg g−1, which can be ascribed to the high pH of the alkaline medium. Zetag and cationic cellulose nanocrystals were selected for harvesting the biomass during semi-continuous cultivation of the microalgal consortium. Both Zetag and cationic cellulose nanocrystals were effective in flocculating the biomass with efficiencies of over 90% during five successive harvesting cycles. Gravity settling of the flocs formed by Zetag and cationic cellulose nanocrystals resulted in low biomass concentration factors of 7.7 and 2.0, respectively. Screening of flocs using a nylon mesh screen (pore size of 180 μm) resulted in a biomass concentration factor as high as 19.8. Zetag and cationic cellulose nanocrystals could be useful in harvesting biomass under high alkaline conditions without detrimental effects on biomass growth., Junta de Castilla y León y programa EU-FEDER (CLU 2017-09) y (UIC 071), FWO-NRF cooperation project (VS00218N), European Union's Horizon 2020 research and innovation programme under grant agreement no 751637

In a fast-growing scenario of environmental decay and resource depletion, the need to reuse industrial wastes has become urgent. Lemon (Citrus limon) seeds constitute the main by-product of industrial processing for the production of juice, pulp slices, and essential oil. In 2016 alone, the global production of lemon fruits was 17.3 million metric tons. The economic and ecological importance of the reutilization of lemon seeds in order to transform waste into a resource can be easily derived. In the past, lemon wastes were basically destined for cattle feed or agricultural fertilization. Nonetheless, the literature reports some studies on lemon seed oil, dating back to the early 1900s, where it was already emphasized that lemon by-products, such as seeds, could be a source of prosperity as well as their parent fruits. Soon after, new reports by oil chemists appeared, with preliminary investigations on the chemical and physical properties of lemon seed extracts and oil. Besides a considerable fraction of oil (around 45%), mainly consisting of beneficial lipids, lemon seeds have been demonstrated to contain nutrients such as proteins, minerals, limonoids, and glucoside derivatives. Therefore, in view of the increasing demand for new sources of edible oils, lemon seed oil has successfully entered the global market of seed oils, but remains a niche product. In this chapter, an overview of chemical composition, biological properties, and common uses and applications of the cold pressed oil are given, with a particular focus on the methodologies used for its production.

The emerging anaerobic dynamic membrane bioreactor (AnDMBR) process is a combination of dynamic membrane (DM) filtration technology with anaerobic digestion (AD), representing an effective alternative for treating various wastewaters, such as high-strength wastewater, municipal wastewater, and organic wastes. The DM layer can be self-formed on large pore-size supporting materials when filtering solutions containing suspended particles, and functions as a virtual filter for effective solid-liquid separation. The AnDMBR process presents comparative performance as the anaerobic membrane bioreactors (AnMBRs) and also shows some unique advantages such as much lower membrane cost and filtration resistance as well as less maintenance requirements. The development of AnDMBR process regarding DM module and bioreactor configuration, and the operation of AnDMBR including DM layer formation and cleaning are presented first. The application of AnDMBR process in wastewater treatment is reviewed in terms of pollutant removal, biogas production, and DM filtration behavior. In addition, some important parameters affecting the design and operation of AnDMBR process are discussed to guide their selection. Finally, perspectives regarding future development and application of AnDMBRs are presented.

Water the universal solvent is needed for drinking, preparing food, bathing, cleaning, irrigating crops and a variety of other tasks. So, treatment of water to remove disease causing organisms is of vital importance. Disease causing agents such as suspended solids, bacteria, algae, viruses, fungi, minerals like iron and manganese, and fertilizers are generally removed during water treatment. Different methods of water treatment are broadly grouped into filtration and disinfection methods for application at the household and community level. Filtration method involves trapping of tiny particles including pathogenic microorganisms and other impurities present in water whereas in disinfection methods contaminants are removed by the use of various chemicals. The purpose of this chapter is to provide adequate information and knowledge about filtration and chemical treatments of waterborne pathogens at both small and large scale, some of the challenges and the future aspects.

Among the potential solutions to a cleaner environment is to minimize the consumption of nonbiodegradable materials and to reduce wastes. The generation and disposal of waste plastics cause severe impacts on the environment. The utilization of solid waste in sustainable constructions has gathered increasing attention due to the lower cost of wastes along with a reduced requirement for landfills. This chapter investigates the feasibility of utilizing waste metalized plastic (WMP) fibers used for food packaging and palm oil fuel ash (POFA) in concrete in terms of physical and mechanical properties. Six fiber volume fractions of 0%–1.25% were used for ordinary Portland cement (OPC) mixtures. In addition, same dosages of fibers were used in mixes with 20% POFA. The results showed that WMP fibers together with POFA reduced the workability of concretes. It has also been found that by adding WMP fibers to the concrete mixtures that the compressive strength decreased for both OPC and POFA mixes at an early stage. Despite having a longer curing time, the mixes contain POFA attained compressive strength greater than those of OPC mixes. The mixture of WMP fibers and POFA subsequently enhanced the tensile and flexural strengths, thereby increasing the ductility as well as the higher impact resistance of concrete. In addition, water absorption, sorptivity, and chloride penetration depth were reduced for concrete mixes incorporating WMP fibers and POFA. The study revealed that the WMP fibers have potential to be used in sustainable concrete by improving the mechanical properties.

In the present work, the influence of the water matrix on the removal of antibiotic resistant bacteria during the electro-disinfection with diamond anodes was studied, paying special attention to the disinfection efficiency and the prevention of the formation of hazardous disinfection by-products. This will allow to evaluate if electrolysis is more suitable as pretreatment of the main pollution source or as tertiary treatment of urban wastewater. To do this, electrolysis of synthetic wastewater rich in ammonium (simulating the effluent of an oxidation pond) and hospital urine intensified with three different bacteria (E. faecalis, K. pneumoniae, and E. coli) were carried out. Results show that the disinfection efficiency is higher in the synthetic wastewater for all the bacteria tested, but chlorate is formed as disinfection by-product. Electrogenerated hypochlorite and chloramines are the main responsible species for bacteria depletion. Presence of organics (urea, creatinine and uric acid) as additional ammonia precursors in hospital urine leads to the well-known breakpoint reaction with electrogenerated active chlorine, yielding an increasing concentration of chloramines. This helps to prevent the formation of chlorate in hospital urine because hypochlorite is mainly wasted in the oxidation of organics and the formation of chloramines. These results are of a great significance because they indicate that antibiotic resistant bacteria can be efficiently removed in complex matrixes without the formation of hazardous chlorine by-products if it is carried out as a pretreatment before discharge to WWTP.

Instability is usually defined in terms of the formation of filterable and non-filterable sludge (sediments, deposits, and gums), an increased peroxide level, and the formation of color bodies. Color bodies in and of themselves do not predict instability. However the reactions that initiate color body formation can be closely linked to heteroatom-containing (i.e., nitrogen-, oxygen-, and sulfur-containing) functional group chemistry. Crude oil constituents are incompatible when sludge, semi-solid, or solid particles (for convenience here, these are termed secondary products to distinguish them from the actual crude oil product) are formed during and after blending. This phenomenon usually occurs prior to use. If the secondary products are marginally soluble in the blended crude oil product, use might detract from solubility of the secondary products and they will appear as sludge or sediment that can be separated by filtration or by extraction. When the secondary products are truly insoluble, they separate and settle out as a semi-solid or solid phase floating in the fuel or are deposited on the walls and floors of containers. In addition, secondary products usually increase the viscosity of the crude oil product. Standing at low temperatures will also cause a viscosity change in certain fuels and lubricants. Usually the viscosity change might be due to separation of paraffins as might occur when diesel fuel and similar, engines are allowed to cool and stand unused overnight in low temperature climates. This chapter presents some of the more prominent methods used for determining instability and incompatibility. No preference is shown and none given to any individual methods. It is the choice of the individual experimentalist to choose the method on the basis of the type of fuel, the immediate needs, and the projected utilization of the data. As elsewhere, it the use of the data that often detracts from an otherwise sound method.

This work focuses on the evaluation of the electrochemical dewatering of sludge obtained in the coagulation of wastes polluted with oxyfluorfen. To do this, sludge samples were treated, aiming not only to reduce the sludge volume, but also to facilitate the degradation of oxyfluorfen contained in the cake via electrolysis with a boron-doped diamond anode. Results show that water can be effectively recovered through three sequential stages. First, a gravity-driven stage, that can recover around 60% of initial volume and where no oxyfluorfen is dragged. Then, a second stage that involves the application of pressure and which accounts for the recuperation of an additional 25% of the total volume of the water removed and in which oxyfluorfen also remained in the cake. Finally, an electrochemical stage, which involves the application of electricity with increasing electric fields (1.0, 2.0, 4.0, and 16.0 V cm−1), accounting for the recovery of the rest of water released and where an electrolytic degradation of oxyfluorfen is obtained, whose extension depends on the electrode configuration used in the electro-dewatering cell. This electrode configuration also influences the retention or loss of oxyfluorfen from the cake, being the optimum choice the placement of the cathode downstream, next to the outlet of the dewatering cell.

In this work the design, synthesis and optimization of a furfural production plant, considering the most abundant and common lignocellulosic wastes of Mexico is proposed. For the process, different pretreatment technologies and different purification process including intensified schemes are considered giving a total of 32 possible process alternatives. The pretreatment technologies are the dilute acid (DA) and ammonia fiber explosion (AFEX) respectively, for the separation zone we considered an azeotropic distillation process, a thermally coupled scheme distillation, a dividing wall column and one liquid- liquid extraction process. A two-stage procedure is used to determine the best process per biomass type. First, the processes are modelled in Aspen plus. Next, the best option per biomass is optimized using the differential evolution with tabu list in order to minimize the total annual cost and the environmental impact. The prescreening results indicate that the dilute acid pretreatment and the thermally coupled distillation provide the lowest cost and environmental impact for furfural production for all the raw materials. The optimization results indicate that a biorefinery with wheat straw as raw material is the best option to produce furfural due to its low cost and environmental impact which are 13 M$/yr and 4,536,512 eco-points/year respectively.

This chapter summarizes the methods for harvesting microalgal biomass and conversion of microalgal lipids into biodiesel. The fundamental harvesting methods, including centrifugation, gravity sedimentation, filtration, flotation, and flocculation, are reviewed. The recently developed biological methods for efficient harvesting of microalgal biomass are addressed. The conventional extraction and transesterification of microalgal lipids into biodiesel are summarized. The advantages of simultaneous extraction and transesterification, so-called direct transesterification, of microalgal lipids into biodiesel are highlighted.

The combination of the filtration capacity of zooplankton (e.g. Daphnia) with the nutrient removal capacity of bacterial/algal biofilm in a zooplankton-containing reactor could provide a natural-based alternative for wastewater treatment. A laboratory-scale zooplankton-based reactor was tested at different HRTs resulting in a significant reduction in nutrient concentrations in wastewater when the system was operated at HRTs longer than 1.1 days (preferably of between 2 and 4 days). However, the presence of high concentrations of organic matter (>250 mg COD L−1) in the wastewater inhibited zooplankton activity, limiting its use to tertiary treatment. Therefore, in combination with other natural treatments that can perform primary and secondary treatments, zooplankton may provide a solution for wastewater clarification and nutrient polishing. The effect of a common metal such as copper on the filtration capacity of Daphnia was also evaluated. Daphnia, as well as the whole zooplankton-based reactor, adapted to copper concentrations of up to 70 μg Cu L−1 but an overload of 380 μg Cu L−1 for two-weeks severely affected the biological system This research was carried out in the framework of the INNOQUA project, which was financially supported by the European Union’s Horizon 2020 research and innovation program under grant agreement No 689817

Recently, the synthesis of carbon nanomaterials such as carbon nanotubes, carbon nanospheres, carbon nanofibers, and graphene from agricultural wastes (or biomass) has been considered to be an advanced topic in scientific and industrial societies. Specifically, carbon nanotubes (CNTs) receive intense research attention worldwide in various applications, including biomedical, energy systems, and environmental remediation because they possess extraordinary properties. Carbonaceous feedstocks such as rice byproducts (straw and husk), wood fiber, sugarcane bagasse, wood, sawdust, etc., can potentially be used to synthesize CNT materials. Recent technologies such as microwave plasma irradiation and catalytic hydrothermal treatment followed by thermal treatment at elevated temperatures using these feedstocks in contrast to direct chemical vapor deposition requiring a light-carbon gas (e.g., cracking of camphor) have been employed to prepare CNTs. Therefore, such trends are not only valorizing biomass waste to achieve high-value nanocarbons, but also solving the polluted environment caused by the huge quantity of biomass waste. Also, the resulting CNTs may be successfully used as efficient, cost-effective, and environmentally friendly adsorbents for the removal of various toxic substrates from wastewater.

Water is the most crucial commodity for life support process in organism. There are various natural and anthropogenic factors that affect the basic physical, chemical, and biological properties of natural water. Among them waterborne pathogens and chemical contaminants are major concerns for public health on local, regional, and global scale, not only with respect to morbidity and mortality but by the high cost of their prevention and treatment. The contamination of water through bacteria, virus, protozoa, and some chemical species are major concerns for waterborne pathogen. This chapter provides a brief overview on conventional chemical treatment technique for wastewater treatment. In accordance with this method, some of the conventional treatment processes are based on coagulation-flocculation, chemical precipitation technique, ion exchange, adsorption, membrane filtration, and electrochemical treatment followed by disinfection used in wastewater treatment, as well as advanced chemical oxidation process such as ozonation, ultraviolet radiation, and chlorination for waterborne pathogen treatment.

Microbial catalyzed electrochemical systems have been intensively used in basic and applied research as a futuristic and sustainable platform for harnessing the energy and generating value-added bioproducts. Recently, more emphasis is being laid on the enhancement of microbial electrolysis (ME) by inserting anaerobic digestion (AD) into it for the conversion of carbon dioxide directly to methane. This chapter is focused on wastewater treatment experience on the beer industry of Harbin city, China, for methane production in innovative integrated ME-assisted upflow AD (ME–AD) reactors. This chapter focuses on three aspects with a particular emphasis on ME–AD scaling up: (1) suitable cathode electrode material, (2) electrodes position and hydraulic retention times (HRTs), and (3) cathode/anode ratio (cathode surface area/anode spatial volume). The combined reactors were thus enabled to achieve maximum organic content removal, enhanced current generation, and heightened methane production, by implementing these upgrading techniques. Ni cathode electrodes were identified to be the most appropriate for employment in the ME–AD reactors. The reactors with electrodes arranged at the bottom side were better in performance at 36 h HRT. The effects of electrode placement on biofilm microbial communities (electrogens and methanogens) were estimated by pyrosequencing methods. A cathode/anode ratio of 2.5 cm2/cm3 was determined to have improved our combined reactor performance. Thus these unique reactors were application-oriented, membrane-free, continuous reactor with shortened reaction time, enhanced electrode ration for improving the bioelectricity generation, and organic content oxidation to methane.

The treatment and disinfection of drinking water continues to be a major public health issue. Natural organic matter (NOM) can react with disinfectants and form disinfection by-products (DBPs). Because of the potential adverse health influence of DBPs, the removal of DBP precursors is required by US Environmental Protection Agency. Owing to variability in DBPs characteristics, complete elimination from drinking water by a single technique is impossible. Membrane filtration processes are effective in removing significant amount of NOM, thus minimizing the formation of carcinogenic DBPs. The most important property of membrane filtration is pore size. By decreasing membrane pore size, the removal of NOMs can be increased. When removing DBPs from drinking water, the process of microfiltration and ultrafiltration is most often supported by adsorption, coagulation, or AOX process.

Essential oils (EOs) are natural products, produced by aromatic plants, with important applications in the food, pharmaceutical, and cosmetic industries. In recent years supercritical fluid extraction with CO2 (SFE-CO2) has emerged as an efficient and environmental friendly method for the recovery of volatile oils from aromatic species, overcoming the limitations of traditional distillation methods. This chapter focuses on the main factors influencing oil recovery by SFE-CO2 from aromatic plants, and on the comparison of this technique with other extraction methods. Many factors and operational conditions greatly affect the extraction yields and the composition of the extracted oil, temperature and pressure being two of the most important factors. Furthermore, reviewed literature based on updated data show that in many plant species, comparing with other extractions methods, SFE-CO2 leads to highest extraction yields, increased oil quality, higher selectivity of the obtained compounds, and improved biological activity.

In this work, a new strategy for the treatment of wastes polluted with micelles is evaluated. It consists on the concentration of the pollutant by electrocoagulation, the pre-treatment of the concentrated sludge with US and the later application of an electrolytic oxidation. As it is well-known that the electrolytic treatment of diluted solutions generally fits well a first-order kinetic, this concentration is expected to lead to a more efficient process. This approach has been studied using oxyfluorfen polluted wastes. Electrocoagulation has been carried out for the concentration of a wastewater containing oxyfluorfen reducing its volume from 50.00 to 1.39 L. Once obtained the small volume of concentrated liquid waste, several treatments have been applied such as Ultrasonic irradiation or heat followed by electrooxidation. Results show that application of US has a very positive influence on the performance, in particular LF-US. Application time is also an important parameter and heating has a negative effect on results because iron hydroxide flocs compress and seal the pollutant inside making more difficult their destruction by the direct and indirect oxidation reactions.

The large volumes of oily wastewater generated by various industries such as oil and gas, food and beverage, and metal processing, need to be deoiled prior to being discharged into the environment. Compared to conventional technologies such as coagulation or solvent extraction, membrane filtration can treat oily wastewater of a much broader compositional range and still ensure high oil removal. The versatility of this technique opened the way for the extensive production of membranes from many types of polymers with a wide range of structures. The extension beyond polymers to inorganic and hybrid materials together with the recourse of advanced preparation techniques gave rise to the production of a wider range of membrane structures, which is thoroughly discussed in this chapter. In addition, the mechanisms involved in the treatment of oily wastewater using polymeric membranes are introduced. Finally, the challenges and future research directions of fiber-based membranes are briefly discussed.

4 Tablas.-- 4 Figuras, A new aeration treatment of black ripe olive streams prior to their vacuum evaporation was studied. It was found that the aeration for two days of these solutions reduced the chemical oxygen demand (COD) of the distillate phase (>80%) generated during their vacuum evaporation; although the temperature (14–38 °C) and the air flow rate (10–50 L air/h/L) had a great influence on this reduction. Moreover, the COD in the distillate was mainly associated with the presence of acetic acid (~400 mg/L) and ethanol (~500 mg/L), the later substance being eliminated by strong aeration. Additionally, the growth of native aerobic microorganisms, mainly Acetobacter, increased the pH of the wastewater to 7–8 units, thus avoiding evaporation of the acetic acid salt formed. These results make the use of the distillate for plant irrigation viable and its discharge into municipal depuration plants possible, given the low COD (, This work was supported by the Spanish Government (Project AGL2016-76820-R, AEI/FEDER, UE).

This paper presents a model-based assessment of the thermochemical conversion of microalgal biomass into Fischer-Tropsch liquids, hydrogen and electricity through polygeneration. Two novel conceptual plants are investigated, which are both comprised of the same operation units (gasification, water-gas shift, Fischer-Tropsch synthesis, upgrading, separation, Rankine cycle and gas turbines) and mainly differ in the location of the water-gas-shift unit. Both plants are found to present a carbon efficiency greater than conventional biomass-to-liquid processes. The most profitable plants in terms of the saleable products yields ca. 0.23 m3 (1.4 bbl) of liquid transportation fuels (gasoline, kerosene and diesel), ca. 16 kg of hydrogen (716.8 scm), and ca. 1.55 × 109 J (430 kW·h) of electricity per 1000 kg of dried microalgae. The corresponding displaced fossil fuels could offset the carbon emissions by 0.56 kg of carbon dioxide for every kg of processed dried microalgae. Nevertheless, predicted break-even prices are lower than 40 USD per ton of dried microalgae in the base case scenario, which is at least 10 times cheaper than the current best scenario for microalgal biomass production. These low prices are a major impediment to the viability of these thermochemical polygeneration plants, albeit presenting a good potential toward cleaner liquid fuel production.

Today, traditional cathode ray tubes are being replaced by versatile flat-panel display technology due to its environmental friendliness, cost effectiveness, and engineering performance. This chapter provides an overview on the progress of display technology including milestones such as flat-panel technologies and consumer electronic devices (e.g., laptop computers and mobile phones). Other cutting-edge technologies include organic light-emitting diodes and electronic paper (e-paper). As discussed in this chapter, flexible electronics can be created by merging new, large-area electronic platforms with traditional materials for innovative large-area system design.

This paper presents an experimental investigation on the durability properties and carbon dioxide (CO2) emissions of concrete developed using waste products. The concrete comprised of recycled concrete aggregate (RA) as a complete coarse aggregate replacement. In addition, rice husk ash (RHA), palm oil fuel ash (POFA) and palm oil clinker powder (POCP) were used as replacement materials for cement at levels up to 30%. The supplementary cementitious materials (SCMs) were used in RA concrete with the aim of reducing the dependency on cement as a stand-alone binder. The compressive strength, water absorption, chloride-ion penetration and electrical resistivity were investigated for RA concrete containing SCMs. Moreover, the residual compressive strength was also examined along with the weight loss to check the elevated temperature resistance of RA concrete with SCMs. The results revealed that the use of 30% RHA as SCM produced the highest compressive strength efficiency of 0.143 MPa/kg cement among all mixes at the age of 90 days. In addition, a significant enhancement was observed for the durability-related properties at later ages, although the engineering properties of RA concrete containing SCMs was low at the age of 28 days. The thermogravimetric (TG) analysis indicated that the RHA is more effective as a pozzolanic additive than POFA and POCP. The CO2 emissions from RA concrete were reduced by approximately 29% when it was incorporated with 30% SCM, where the eco-strength efficiency showed the highest values at 20% cement replacement level of 20%.

Granular activated carbon (GAC) is applied as post-treatment technology in wastewater treatment plants (WWTPs) in order to increase the elimination of organic micropollutants (OMPs). However, the efficiency and life-time of GAC depend on several parameters, such as the quality of the effluent to be treated or the type of GAC. In the present paper, two types of GAC, based on bituminous carbon (BC-GAC) and coconut shell (CS-GAC), were assessed from a technical, economic and environmental point of view to further remove OMPs present in two secondary effluents, coming from integrated biological systems with a membrane or a settler, respectively. Although all GAC filters were efficient in removing selected OMPs, the quality of the secondary effluent had a strong influence on the lifespan of adsorbent material and the technical operability of the filtration systems. While GAC filters treating membrane effluent were highly effective to remove recalcitrant compounds, such as carbamazepine and diazepam (>80%), even after 430 d of operation (>30,800 BV), the efficiency of GAC filters treating settler effluent quickly lowered to 50% after 100 d of operation (

This chapter covers some of the more common instrumental methods used for the qualitative and quantitative analysis of materials. Important parameters to be considered in the comparison of instrumental methods are reviewed including: accuracy, precision, detection limits, sensitivity, and resolution. The principles of chromatography are introduced with paper chromatography and later applied to thin layer chromatography, gas chromatography, and liquid chromatography (HPLC). Atomic absorption and atomic emission are reviewed as important methods for measurement of metals and a case study on the determination of wear metals is given as an example. UV-visible absorption spectroscopy and Fourier transform infrared (FTIR) absorption spectroscopy are reviewed. The theory and applications of the three luminescence spectroscopies: fluorescence, phosphorescence, and chemiluminescence, are discussed. Mass spectrometry and nuclear magnetic resonance spectroscopy are stressed as important methods for chemical structural determination.

Despite the numerous processes proposed as alternatives to heat pasteurization, thermally treated juices produced by full or flash pasteurization are still the most widely marketed product. It is well known that the flavor of fruit juices is influenced by heat treatment used for microbial stabilization; as an example, volatile compounds, such as alpha-terpineol and the terpinen-4-ol synthesized during heat treatments are responsible for the “oxidized” and “cooked” flavors of the orange juice. In addition, between the setting out of bottle and the consumption of the fruit juice, it can occur several days even several weeks. Food is subjected to the laws of aging and chemical additives are often used to stabilize fruit drinks, and in such an objective, gases may offer new perspectives; in this chapter the use of oxygen, nitrogen, carbon dioxide, and hydrogen are investigated.

This chapter is concerned with flocculation and electroflocculation of algal cells. Flocculation and electroflocculation are methods for causing the freely suspended algal cells to agglomerate, or coagulate, into larger particles, or flocs, for rapid sedimentation by gravity. Implementation of these separation methods and their mechanisms are discussed. Flocculants, or the chemical additives used to achieve flocculation, are discussed. Flocculation followed by gravity sedimentation of flocs is used to remove much of the water from an algal suspension prior to further dewatering by other means. Flocculation and electroflocculation are among the most economic methods of concentrating an algal suspension to reduce the cost of further dewatering by methods such as centrifugation and filtration.

In this chapter, the issue of petroleum and refinery wastewater is discussed. A brief review of petroleum and oily wastewater characterization and primary (physical) treatments, such as API separators, sedimentation, electrodialysis methods, catalytic vacuum distillation, biological treatments, and DAF, is provided. Furthermore, separation processes including adsorption, AOP distillation, and other new technologies are discussed with the purpose of eliminating organic compounds. The main focus of this section is on the removal methods of BTEX, phenol, and its derivatives. As for the new technologies in wastewater treatment and management, low-pressure membrane processes and the advancements are summarized. The operation conditions and membrane characterization of UF, MF, and NF have been compared. Among the various separation technologies described for reducing contaminants, activated carbon is further explored in this study, and the use of different adsorbents for removal of CODs, phenol, and heavy metals is reviewed. Improvement strategies and future opportunities for the enhancement of wastewater treatment methods, mainly membrane technologies and adsorption, are proposed.

Probiotic microorganisms are usually carried in dairy food matrices. New trends and the diversification of tastes in consumers have expanded the study of new matrices for probiotic vehicle. In this proposal, pumpkin by-products (peel and pulp) were used as substrate/support of Lactobacillus casei ATCC 393. Therefore, a new ingredient was developed containing L. casei immobilized in a pumpkin matrix. This new product was incorporated as a supplement into two different beverages: chocolate milk and soy milk containing apple juice. The two commercial beverages, supplemented with L. casei cells immobilized in the pumpkin tissue, presented a high percentage of the probiotic cell survival (≈ 80%) in simulated gastrointestinal digestion conditions compared to free L. casei cells. The rheology of the supplemented beverages was modified as a result of supplement incorporation. Sensory evaluation of supplemented beverages received scores > 6 on a 9-point hedonic scale in odor, texture, and overall acceptability.

Dyes are unacceptable environmental pollutants. Their removal has been a long-time goal due to their high toxicity and perseverance. Adsorbents such as commercial activated carbon, graphene oxide, and chitosan may be used to treat wastewater; however its high cost limits the ability to use it. This resulted in finding other lower cost adsorbents. This chapter will investigate the use of inexpensive raw materials that can offer low-cost recipes instead.

Mescal is a regional alcoholic beverage with denomination of origin; this category has been granted to the beverage produced in three states of the Mexican Republic. However, most of the mescal is produced in a traditional way without quality control, mainly in the fermentation step spontaneous fermentations are used by autochthonous strains and in some cases baking yeasts. The raw materials used for mescal elaboration are different species of Agave. The process of mescal production basically consists of six stages: selection of the raw material, cutting, cooking, grinding, fermentation, and distillation. During the selection, plants at least 8-years old are chosen, then farmers proceed with the jima (cutting of the leaves and extraction of the pineapple). Later, the pineapples (heart of the agave) are placed on a natural oven, consisting of a circular excavation forming a large container covered with stones previously heated with firewood. After that, cooking step is performed in which polysaccharides (fructans) are hydrolyzed to obtain fructose-rich syrup. Then, pineapples grinded to reduce its size and more sugars are made available for fermentation. In this last step, the must resulting from the milling process is placed in wooden jars where it is fermented naturally for 4–5 days. This stage is carried out with native yeasts or with selected strains which transform the sugars into ethanol. Finally, during the first distillation the so-called wine water is obtained, which have 15%–25% alcohol. Later this product is taken for second distillation where it concentrates until have 45%–50% of alcohol, obtaining a product of greater purity also called young mescal. The purpose of this document is to review all the mescal process, discuss its chemical and physical properties, and the microorganisms involved in mescal fermentation.

Membrane filtration is widely used in the dairy industry. This chapter provides an overview of the various applications of reverse osmosis, nanofiltration, ultrafiltration, and microfiltration in the processing of milk, and dairy waste streams. A summary of milk composition and chemistry is provided in relation to membrane processing. Applications of membrane filtration in milk processing are then discussed, including on-farm concentration of milk, removal of microorganisms, and fractionation of protein and fat. Coverage also includes the use of membranes for standardizing the composition of cheese milk, processing and concentration of whey and whey proteins, and purification and treatment of dairy wastes. Recent progress in the understanding of flux decline and fouling in dairy membrane filtration is outlined, along with the potential application of ultrasound.

Scarcity and contamination of worldwide drinking water demand advanced, effective water purification methodologies. Eliminating numerous contaminants, such as heavy metals, toxic textile dyes, pesticides, oil, and other industrial, as well as agricultural, wastes, from water has become a serious concern because of their adverse effects on human health and the ecosystem. Recently, developments in nanoscience and nanotechnology propose that several of the present problems relating to water quality could be greatly reduced by using nanomaterials because of their good adsorption efficiency, higher surface area, and greater active sites for interaction with contaminants in water. In this context, nanocellulose is the most abundant and renewable polymer available globally and consists of repeating β- d -glucopyranose units covalently linked through acetal functions between the hydroxyl groups of C4 and C1 carbon atoms that provide it chirality and reactivity properties. Nanocellulose is a fascinating material for practical applications because it is cost-effective, is renewable, and can be handled at huge scale using conventional wood industry techniques. Nanocellulose is a valuable filtration material because it is affordable, sustainable, inert, and stable at a broad range of pH/ionic strength. Moreover, the abundant availability of the surface hydroxyl groups on the nanocellulose facilitates various surface chemistries that can be explored for targeting various contaminants in water. This chapter covers the recent developments and literature of nanocellulose in the field of water purification.

The dehydration of sewage sludge consists in lowering the water content of sediments and increasing the dry matter content. It is the key process for posttreatment and further processing of sewage sludge. During this process, the reduction of the volume of sewage sludge occurs simultaneously. The removal of water from sewage sludge is realized in the processes of compaction, drainage, and drying. Depending on the type of water contained in the sewage sludge, various methods are needed to remove it. There are several types of sludge that have specific characteristics that will influence the choice of conditioning chemicals (cationic flocculant, ferric chloride, lime, etc.) and the choice in the dewatering equipment to be used (filtration, centrifuge, etc.). These choices will also depend on the final use of the sludge (incineration, agricultural spreading, etc.) as well as equipment resources.

This chapter focuses on the production of biohydrogen in microbial electrolysis cells (MEC). MEC is an attractive technology that can simultaneously remove organics and produce biohydrogen gas. Theoretical aspects related to MEC systems are reviewed. Parameters affecting the MEC performance, such as cell architecture, membranes, inoculum, and microorganisms developed, are discussed. In addition, the influence of the anode and cathode materials is analyzed. MEC performances for biohydrogen production under different types of anolytes and catholytes are presented. Finally, future needs are considered for the practical application of this technology.

After maturation, most of beers are filtered and pasteurized. Such processes aim to purify the beer, clarify, and reduce total microorganism count. Filtration with diatomaceous earth (DE) and pasteurization (slow or fast) are usually performed. However, these processes have some drawbacks. DE wastes can cause environmental problems, while pasteurization is a high-energy expenditure technology. An alternative against the current model of beer filtration is the use of membrane separation processes, especially microfiltration. Therefore, this book chapter provides a critical and constructive overview of microfiltration applied to beer processing. The aim is to present to the scientific community a detailed assessment of microfiltration for improving the quality of beers. Recent advances and future outlooks on the use of emerging technologies related to purification of beers are also presented. A case study regarding the microfiltration of Blond Ale, Weiss Bier, and Pale Ale beers using poly(etherimide) membranes is provided. The parameters, such as color and turbidity removal, bitterness retention, phenolics compounds, tannins, antioxidant activity variation, and microorganisms count are presented and discussed. Then, the information provided in this chapter can encourage researchers to develop promising studies on the purification of beverages using membranes.

A few emerging energy-efficient technologies, which can help achieve minimum energy consumption, are presented in this chapter. These include: gas-fired paper dryer; air impingement drying; steam impingement drying; impulse drying; infrared drying; Multiport dryer; Boost Dryer; advanced fibrous fillers; microwave drying; Aq-vane technology; displacement pressing; laser ultrasonic stiffness sensor; new flotation deinking processes; surfactant spray deinking; pulsed power technology for decontamination of recycled paper; directed green liquor utilization pulping; membrane concentration of black liquor; dual-pressure reheat recovery boiler; borate autocausticizing; steam cycle washing; black liquor gasification; lignoBoost; hemicellulose extraction before chemical pulping; use of residuals in concrete production; chemical pretreatment with oxalic acid for mechanical pulping; biological pretreatment for mechanical pulping (enzymatic pretreatment, fungal pretreatment); enzymatic prebleaching; enzymatic refining; enzymes for drainage improvement; enzymatic deinking; enzymatic debarking; enzymatic removal of shives; enzymes for reduction of vessels in tropical hardwoods.

Therapeutic drug monitoring (TDM) is a part of personalized medicine. Even if there is no evidence from randomized trials, the clinical value of thoughtfully and appropriately used TDM for so-called older antiepileptic drugs (AEDs) (eg, phenytoin, valproates, carbamazepine, and phenobarbital) is well established in clinical practice. A position paper by the subcommission on TDM, International League Against Epilepsy Commission on Therapeutic Strategies, in 2008 suggested new definitions, and the concept of “an individual therapeutic concentration,” not a general reference range, was recommended. This chapter summarizes the lengthy experience with TDM, population pharmacokinetics (PK) modeling, and individualizing dosage regimens of older AEDs given as monotherapy and polytherapy. Anticonvulsant monitoring of adult and pediatric patients have been routinely collected in PK services in Russia since the 1990s and analyzed retrospectively. The relatively rich TDM data (peak–trough sampling strategy, repeated measurements over 1- to 6-year periods in some patients) make it possible not only to develop simple linear and more complex nonlinear population PK models for individualizing dosage regimens, but also to evaluate how well this method works in real clinical settings. For TDM of AEDs, future developments include AED measurement in saliva and other less invasive methods. Portable near-patient testing devices, minimally invasive, simple, and low-cost methods for online TDM enable wider and more effective implementation of TDM. Continuous sampling may permit more complex PK models for drugs or drug combinations to be identified from such “rich” TDM data and used for dosage individualization. More intensive TDM procedures open a possibility for investigation of relationship between PK and pharmacodynamic measures as well as PK/PD modeling of AEDs.

Wastewater from pressurized fixed bed coal gasification has been all along regarded as one of the most difficult water to treat. It contains high concentration of phenols and ammonia. The most efficient treatment method is distillation and extraction. Phenols and ammonia are recovered as products. However, energy consumption, in the form of low-pressure steam and mid-pressure steam, is relatively high. Energy consumption of the wastewater treatment process developed by South China University of Technology is analyzed in this paper. Two integration processes based on SCUT wastewater treatment process are proposed in which solvent recovery system is thermally integrated. The results indicate that these integrations decrease energy consumption by about 18% compared to the conventional SCUT process. The cost of wastewater treatment can reduce to 0.2 CNY/ton of wastewater. The competitiveness of the technology for wastewater treatment is improved.

The use of enzymes has been suggested as an environmentally friendly alternative to complement conventional chemical deinking in the recycling of recovered paper. Enzymes could reduce the demand for chemicals and would lower the process costs and the environmental impact. These enzymes include cellulases, hemicellulases, pectinases, amylases, lipases, esterases and laccases. Among the different enzymes studied, deinking using carbohydrate hydrolases, which have activities in cellulose and hemicellulose hydrolysis, has been widely demonstrated on different secondary fibres. Brightness response to enzyme treatment varies considerably, but it often rivals or surpasses brightnesses obtained with conventional deinking processes. Residual dirt count for enzymatically deinked pulps is also generally lower. Additional benefits include higher freeness and greater paper strength. Results for pulp yield are inconclusive. Extensive research has demonstrated the application of enzymes and their effectiveness. Different mechanisms for ink removal by enzymes have also been proposed. Operating conditions must be optimised for successful deinking. Although the potential of enzyme-based deinking appears good, further research in a few areas is needed to exploit this technology fully.

The pulp and paper industry has been exploring alternative chemical recovery technologies to replace or augment the conventional Tomlinson boiler system since the 1970s. Among these, black liquor gasification (BLG) has shown some interesting promise. BLG is a process in which a clean synthesis gas is produced from black liquor by converting its biomass content into gaseous energy carrier. The syngas subsequently can be used in boilers or in combined cycle processes (utilizing gas turbines) to generate on-site electricity and/or process steam. The potential advantages of BLG are the greater end use flexibility offered by a gaseous fuel, reduced air pollutant content, and higher electricity-to-heat ratios in combined cycle systems than standard recovery boiler steam turbine systems. The general background of the pulp and paper industry, the pulp and paper making process, kraft pulping process, recovery cycle, and modern kraft mills are presented in this chapter.

Recycled fibre is a major source of raw material for the modern recycled paper mill. Stickies are a major obstacle to manufacturing high-quality paper. They are natural components of the recycled fibre used by the mills. Stickies are tacky, hydrophobic, pliable organic material found in recycled paper systems. They exhibit a broad range of melting points and different degrees of tackiness depending on their composition. Stickies are composed of a variety of materials including adhesives, styrene–butadiene latex, rubber, vinyl acetate and hot melts, etc. The variable nature of stickies and the variability of the composition of recycled fibre used by paper and board mills make them more difficult to control. Stickie contaminants are a costly problem both for recyclers of market pulp and for the papermakers using it. Stickies challenge the process of using recycled or secondary fibre sources. In addition, they tend to deposit on machine surfaces, fabrics, wires, felts and rolls, which leads to runnability problems such as paper breaks at the press. If not controlled, stickies can also lead to paper quality issues such as holes, sheet defects and high dirt counts. Several methods have been proposed for controlling stickies. Chemical methods involve dispersants, polymers and absorbents. Mechanical methods use screens, cleaners, dissolved air flotation and washing stages. Enzymes are the sustainable alternative to chemicals. They efficiently convert the stickies into more manageable components, thereby improving machine performance. More importantly, enzymes have the ability to improve the recycled paper’s quality in terms of spots, holes and breakage as well as preventing damage from stickies. Several case studies explain the effect of using enzymes in mill situations, producing results such as a 90% reduction in stickies and an increase in brightness across the deinking facility, production performance improvements, a reduction in the use of cleaning solvents and significant reduction in downtime caused by stickies. The Optimyze product line from Buckman is successfully being used in many mills around the world.