Industrial Wastewater Treatment Technologies For Reuse, Recycle, And Recovery: Advantages, Disadvantages, And Gaps.

To reduce demand and discharge, instead of industrial wastewater being poorly treated and disposed of, it can be recycled, reused, or recovered if it is properly managed, thus having a substantial decrease in the water requirement and environmental impacts. The challenge is to select the appropriate process or combination of processes to achieve this based on the wastewater quality. Consequently, the objective of this investigation is to review every technology from conventional through advanced, for reliable and sustainable wastewater treatment and derived sludges, focusing on advantages, disadvantages, and technical gaps for development. Even though there is a wide range of possible technologies, it was evinced that there is huge potential to exploit and make them economically and sustainably viable for waste processing and circular economy, even in the mature massively implemented wastewater treatment technologies in the industry. Overall, we identify that independently from the technology to be studied, the future investigations on every unit, especially on those not vastly implemented, should be focused on: (1) The capacity in removing selected pollutants and decreasing impurities, (2) energy efficiency, (3) environmental safety, (4) economic viability, (5) hybrid processes, and (6) sustainability by waste processing.

A Review on Laser-Assisted Joining of Aluminium Alloys to Other Metals

Modern industry requires different advanced metallic alloys with specific properties since conventional steels cannot cover all requirements. Aluminium alloys are becoming more popular, due to their low weight, high corrosion resistance, and relatively high strength. They possess respectable electrical conductivity, and their application extends to the energy sector. There is a high demand in joining aluminium alloys with other metals, such as steels, copper, and titanium. The joining of two or more metals is challenging, due to formation of the intermetallic compound (IMC) layer with excessive brittleness. High differences in the thermophysical properties cause distortions, cracking, improper dilution, and numerous weld imperfections, having an adverse effect on strength. Laser beam as a high concentration energy source is an alternative welding method for highly conductive metals, with significant improvement in productivity, compared to conventional joining processes. It may provide lower heat input and reduce the thickness of the IMC layer. The laser beam can be combined with arc-forming hybrid processes for wider control over thermal cycle. Apart from the IMC layer thickness, there are many other factors that have a strong effect on the weld integrity; their optimisation and innovation is a key to successfully delivering high-quality joints.

Microwave Technology for Hybrid Fabrication Processes

This paper aims to present how the microwave technology can be used in the development of hybrid joining and microjoining technologies for composites materials in order to increase productivity and quality of the welds. The paper is mainly focused on conceptualization of various types of hybrid processes by coupling a microwave beam with conventional thermal source such as arc welding, laser welding, 3D printing and others. The concepts presented in this paper will be completed with sensing solution for sensing and automation of the processes.

“Tying your ngemb”: Negotiating identity in Senegalese wrestling

More than merely a combat sport, Senegalese wrestling combines professional athleticism with cultural traditions, political relations, and religious belief. For many young men in Senegal, wrestling also represents a model of success in otherwise challenging circumstances characterized by socio-economic crisis and increasing precarity. Young wrestlers must navigate and perform an elaborate set of identities in order to demonstrate their success—both within the sand-filled arenas in which fights take place, and in the complex social worlds which have emerged around the practice. Referring to a panoply of identity markers including ethnicity, religious affiliation, and village or neighborhood loyalty, wrestlers simultaneously demonstrate their alignment with dominant discourses around masculinity and urban knowledge. The article draws upon lengthy ethnographic research to explore the dynamic, contradictory, and hybrid processes of identity construction through which wrestlers present themselves to the world.

Fate of Benzophenone, Benzophenone-3 and Caffeine in Lab-Scale Direct River Water Treatment by Hybrid Processes

Emerging microcontaminants benzophenone (BP), benzophenone-3 (BP-3) and caffeine (CF) are widely used anthropogenic markers from a group of pharmaceuticals and personal care products. They have different logD values and charges at neutral pH (2.96 neutral for BP; 3.65 negative and neutral for BP-3; 0.28 and neutral for CF). The goal of this study was to assess the efficacy of coagulation/flocculation/sedimentation (C/F/S), adsorption onto two types of powdered activated carbon (PAC)/sedimentation (PAC/S) and the combination of these two processes in different dosing sequences (PAC/C/F/S) and with/without ultrafiltration (powdered activated carbon/ultrafiltration—PAC/UF, coagulation/UF—CoA/UF) for the removal of selected micropollutants from river water. It was shown that the removal efficiency of benzophenones by coagulation depends on the season, while CF was moderately removed (40–70%). The removal of neutral BP by two PACs unexpectedly differed (near 40% and ˃93%), while the removal of BP-3 was excellent (>95%). PACs were not efficient for the removal of hydrophilic CF. Combined PAC/C/F/S yielded excellent removal for BP and BP-3 regardless of PAC type only when the PAC addition was followed by C/F/S, while C/F/S efficiency for CF diminished. The combination of UF with PAC or coagulant showed also high efficacy for benzophenones, but was negligible for CF removal.

Adsorption-Membrane Hybrid Approach for the Removal of Azithromycin from Water: An Attempt to Minimize Drug Resistance Problem

In this study, activated carbon (AC) and magnetic activated carbon (MAC) were prepared from Dalbergia sissoo sawdust for the removal of antibiotic Azithromycin (AZM) from aqueous solution. The effect of initial concentration, contact time, pH, adsorbent dosage, and the temperature were investigated for both the adsorbents. The optimum AZM concentration, contact time, pH and adsorbents dosages were found to be 80 mg/L, 120 min, 6 and 7 (pH, respectively, for AC and MAC), and 0.1 g (for both AC and MAC), respectively. The isothermal data of both sets of experiments correlated well with the Langmuir isotherm model, while the kinetic data with the pseudo-second-order model. The adsorption of AZM on both adsorbents was found to be favorable, which is evident in the values of the thermodynamic parameters (ΔH = −26.506 and −24.149 KJ/mol, ΔS = 91.812 and 81.991 J/mol K, respectively, for AC and MAC). To evaluate the effect of AC and MAC on the membrane parameters, a continuous stirred reactor was connected with ultrafiltration (UF), nanofiltration (NF), and reverse osmosis (RO) membranes. High % retention and improved permeate flux (around 90%) were obtained for AC/UF, AC/NF AC/RO, MAC/UF, MAC/NF, and MAC/RO treatments. The percent retention of AZM observed for AC/UF, AC/NF AC/RO was higher than MAC/UF, MAC/NF, and for MAC/RO hybrid processes due to greater surface area of AC than MAC.

A Review on Advanced Manufacturing Techniques and Their Applications

Advancement in manufacturing processes has drawn preeminent interest from researchers and industry, it makes the process of manufacturing more productive and capable of high efficiency. Advancement of technology has been done by several approaches to combine different manufacturing processes with similar objectives of increasing material removal rate, improving surface integrity, reducing tool wear, reducing production time, and extending application areas. A combination of different processes has been called ‘Hybrid’ processes by various researchers, engineers, and industry expert. Hybrid processes open new opportunities and applications for manufacturing various components that are not able to be produced economically by processes on their own. This review report starts with the classification of current manufacturing processes based on the nature of the processing. The main part of this report is reviews of existing and widely used manufacturing processes that recently reported in a decade. Purpose of this report to produce an overview of these different processes by reviewing various research papers.