The presence of heavy metals in water bodies is linked to the increasing number of industries and populations. This has serious consequences for the quality of human health and the environment. In accordance with this issue, water and wastewater treatment technologies including ion exchange, chemical extraction, and hydrolysis should be conducted as a first water purification stage. However, the sequestration of these toxic substances tends to be expensive, especially for large scale treatment methods that require tedious control and have limited efficiency. Therefore, adsorption methods using adsorbents derived from biomass represent a promising alternative due to their great efficiency and abundance. Algal and seaweed biomass has appeared as a sustainable solution for environmentally friendly adsorbent production. This review further discusses recent developments in the use of algal and seaweed biomass as potential sorbent for heavy metal bioremediation. In addition, relevant aspects like metal toxicity, adsorption mechanism, and parameters affecting the completion of adsorption process are also highlighted. Overall, the critical conclusion drawn is that algae and seaweed biomass can be used to sustainably eliminate heavy metals from wastewater.

In this review article, the recent development of organic sorbents derived from plant and animal waste for treating polluted aqueous media is presented. The application of biomass has been recognized reliable to adsorb hazardous pollutants contained in wastewater generated by emerging industries. This paper also discusses other existing technologies for removing pollutants including heavy metals, dyes, oil and grease, antibiotic and phenolic compounds from polluted aqueous media. Furthermore, several prominent examples of plant and animal wastes such as eucalyptus bark, pine bark, rice husk, various fruit peels, and animal bones are also properly reviewed. The effects of modification techniques on sorbent performance such as carbonization, pyrolysis, and chemical impregnation using acid or alkaline chemicals are considerably included. Some gaps in current literature are also discussed including the tendency of certain targeted pollutants, the use of simulated aqueous media, the scale of research projects, and the prominent modification procedures. Eventually, based on the relevant literature, clear conclusion has been drawn that these natural disposals have great potentiality as environmentally friendly sorbent alternative to other commercial expensive sorbents, and their reuse has been part of green solutions supporting a circular economy system.

Current development of membrane technology for purifying polluted water and wastewater is discussed in this review in accordance with its hybrid application with other types of water treatment methods such as adsorption, advanced oxidation processes (AOPs), and biological activated sludge. This hybrid implementation aims are to lengthen membrane lifespan and elude severe fouling on the surface and pore of the membrane. Membrane material and fabrication technology were concisely included. Two prominent materials to fabricate membrane namely polymeric and ceramic are reviewed well along with the exploration of biopolymers based-materials such as starch and alginate. Several fabrication methods available to be implemented in research or industrial large scale including interfacial polymerization technique, non-solvent induced phase separation, temperature induced phase separation, electrospinning, and sintering are deliberately discussed. The next section includes fouling analysis involving reliable fouling mechanism namely Hermia’s models to help with the explanation of fouling occurrence during filtration. These models covers four different mechanisms namely complete blocking, standard blocking, intermediate blocking, and cake filtration models. Ultimately, recent research reporting the outcome of the hybridization of membrane and adsorption, biosorption, coagulation-flocculation, AOPs, and biological treatment using microorganism were properly reviewed. Overall, this review considerably promotes the findings of those works which mostly revealed positive outcome of the hybrid membrane system contributing to stronger foundation for future research.

Background: Workers who are exposed to extreme heat may be at high risk of heat stresswhich can affect the workers’ health and reduce their work productivity. This study aimed to analyzedehydration index and fatigue level of employees working in heat-exposed environments. Methods: The participants of this cross-sectional descriptive study were 52 employees working on shoveling sand. The urine and peripheral blood of the research subjects were taken for laboratory analysis. The dehydration index was determined from the color, specific gravity, and acidity of urine and from the hematocrit level of blood. The heat stresswas assessed using the indicators of wet-bulb globe temperature(WBGT)and the amount of UV exposure. Fatigue levelwas measured using occupational fatigue questionnaires referring to Subjective Self Rating Test (SSRT).Results: The results of heat stressmeasurement showed that the average of WBGT was above the threshold limit value, and it meant that the workload of workerswas high. All workers (100%) were exposed to UV radiation that higher than recomended thethreshold limit value.It was found that 11% of the workers were dehydrated based on hematocrit levels and 25% of those was dehydrated based on urine pH level test. Dehydration index based on urine color observationrevealed that 52% of workers were severely dehydrated, whereas based on the urine specific gravity 72.3% of the workers were moderately dehydrated. The measurement of fatigue level showed that 89% of the workers developed mild fatigue. Conclusion: Heat-exposed environments could make some changes in dehydration index and cause mild fatigue in workers. It is necessary for people working in heat-exposed environmentsto have regular medical check-ups and maintain the balance of body fluids.

Mitra Pangan Sejahteramerupakan usaha mikro kecil dan menengah (UMKM)di Karang Pamulang, Mandalajati, Kota Bandung, Jawa Barat yang bergerak dibidang produksi tempe. Saat ini CV. Mitra Pangan Sejahtera berharap untuk bisa mengolah 1 ton kedelai setiap harinya guna memenuhi kebutuhan konsumen. Namun, dalam proses produksi tempe ada beberapa proses yang memakan waktu. Salah satunya pada proses pemisahan kulit ari dari kacang kedelai. Proses pemisahan kulit dan kacang kedelai yang dilakukan selama ini adalah dengan pengadukan dan penyaringan secara manual menggunakan tangan dan bantuan ayakan bambu sederhana. Cara ini hanya efektif untuk jumlah yang kecil, yaitu sekitar 4 kuintal/hari. Untuk meningkatkan kemampuan produksi tempe, proses pemisahan tersebut harus dikembangkan. Dengan adanya mesin pengupas kulit ari maka tidak banyak tenaga yang diperlukan dan proses pemisahan kulit dari kacangnya dapat dilakukan lebih cepat sehingga meningkatkan produktifitas dan efisiensi.

Objectives : This comparative study investigated various methods of advanced oxidation processes (AOPs) that were separately conducted for treating raw petroleum refinery effluent regarding chemical oxygen demand (COD) removal.Methods : Fenton, photo-Fenton, TiO2, ZnO, TiO2/Ultra violet (UV), and ZnO/UV were performed individually for measuring the effect of light irradiation, treatment time, pH, catalysts dosage, and light source on the profile of COD values.Results and Discussion : The experimental data of this work showed that the dependency on the light exposure in heterogeneous photo-catalytic reaction using TiO2 and ZnO is higher than that of homogeneous photo-Fenton technique. The optimum operating conditions in heterogeneous system occurred at 100 min of oxidation time, pH 5, and catalyst dosage 1 g/L that resulted in 21.8, 20.68, 60.9, and 55.17% of COD removal for TiO2, ZnO, TiO2/UV, and ZnO/UV, respectively. In contrast, both Fenton and photo-Fenton experienced their highest performance at pH 4 by obtaining 44.2 and 59.77% of COD removal, respectively. Eventually, kinetic study indicated that COD degradation can be well expressed by second-order pattern that reached higher correlation coefficient values by 0.999 and 0.998 for TiO2/UV and TiO2, respectively.Conclusions : Overall, it could be assumed that AOPs are reliable techniques to purify raw and complex raw industrial effluents.