High Biological Oxygen Demand Research Articles

Impact of untreated tannery wastewater in the evolution of multidrug-resistant bacteria in Bangladesh

The tannery industry produces one of the worst contaminants, and unsafe disposal in nearby waterbodies and landfills has become an imminent threat to public health, especially when the resulting multidrug-resistant bacteria and heavy metals enter community settings and animal food chains. In this study, we have collected 10 tannery wastewater (TWW) samples and 10 additional non-tannery wastewater (NTW) samples to compare the chemical oxygen demand (COD), pH, biological oxygen demand (BOD), dissolved oxygen (DO), total dissolved solids (TDS), chromium concentration, bacterial load, and antibiotic resistance profiles. While COD, pH, and chromium concentration data were previously published from our lab, this part of the study uncovers that TWW samples had a significantly higher bacterial load, compared to the non-tannery wastewater samples (5.89 × 104 and 9.38 × 103 cfu/mL, respectively), higher BOD and TDS values, and significantly lower DO values. The results showed that 53.4, 46.7, 40.0, and 40.0% of the TWW isolates were resistant to ceftriaxone, erythromycin, nalidixic acid, and azithromycin, respectively. On the other hand, 20.0, 30.0, 50.0, and 40.0% of the NTW isolates were resistant to the same antibiotics, respectively. These findings suggest that the TWW isolates were more resistant to antibiotics than the NTW isolates. Moreover, the TWW isolates exhibited higher multidrug resistance than the NTW isolates, 33.33, and 20.00%, respectively. Furthermore, spearman correlation analysis depicts that there is a negative correlation between BOD and bacterial load up to a certain level (r = − 0.7749, p = 0.0085). In addition, there is also a consistent negative correlation between COD and bacterial load (r = − 0.7112, p = 0.0252) and TDS and bacterial load (r = − 0.7621, p = 0.0104). These findings suggest that TWW could pose a significant risk to public health and the environment and highlight the importance of proper wastewater treatment in tannery industries.

Reduced seagrass resilience due to environmental and anthropogenic effects may lead to future die-off events in Florida Bay

Coastal systems often depend on foundation species such as seagrasses that are supported by self-facilitation. Seagrass meadows, however, are threatened worldwide due to climate change and local human impact, disrupting self-facilitation leading to system instability. Florida Bay is a large seagrass dominated coastal ecosystem that suffered from multiple seagrass mortality events over the last half century driven by hypoxia, high water temperatures, hypersalinity, and high biological oxygen demand. These conditions reduce the amount of photosynthetically-derived oxygen in the plant causing sulphide intrusion into meristematic tissues. Using a bay-wide sampling design and long-term monitoring trends of seagrass condition, we investigated the current state of the meadows, sediment characteristics (e.g., organic matter, sulphide, nutrients) and discuss how climate stressors interact with plant and sediment oxygen dynamics. Our survey revealed that at sites where seagrass had been previously denuded by die-off, the dominant seagrass Thalassia testudinum had not recovered, while the pioneering seagrass Halodule wrightii recolonized the impacted areas. Organic matter and sulphide levels were higher at the impacted sites, apparently a persistent characteristic of the formerly dense T. testudinum meadows in central and western Florida Bay. These sediment conditions promote sulphide intrusion of T. testudinum belowground tissue under anoxic conditions. Plant oxidation initially buffers sulphide intrusion, but disruption of this oxidation mechanism due to changing environmental conditions results in widespread mortality and seagrass community collapse. Climate change cannot be fully mitigated by local management, however, attempts can be made to control critical salinity and oxygen levels by increasing freshwater input, reducing hypersalinity and aiming to keep the internal seagrass oxidation feedback intact. Our study shows that the Florida Bay seagrass ecosystem is still recovering four years post die-off and continues to be susceptible to future climate change and system degradation.

Development of Whey Beverages from Paneer Preparation Using Fruit Coagulants: A Comparative Study on Physicochemical and Sensory Properties

Whey is a by-product of milk generated during the preparation of coagulated milk products. However, whey disposal results in serious environmental pollution due to its high biological oxygen demand. Therefore, whey generated from the preparation of Indian soft cheese (paneer) by coagulating heated milk with 2% citric acid solution (control) lemon or Indian gooseberry (amla) extracts was collected and mixed with sugar, colour, and flavour were used to develop whey beverages. The whey and whey beverages were analysed for physicochemical and sensory properties. Whey from lemon extract contained higher total solids, fat and protein content than citric acid and amla extract. The ascorbic acid content was higher in amla (56.5 mg/100g) than in lemon whey (6.76 mg/100g) and was not detected in control. The total phenols (GAE mg/100g) and tannins (mg/100g) respectively were higher in amla (550; 394.45) than in lemon (69.23; 4.08) and citric acid (5.86; 0.00). The antioxidant activity was higher in whey from lemon extract (88.77%) than amla (81.38%) and citric acid (14.39%). The whey beverages from both fruit extracts were highly acceptable. Therefore, whey generated from paneer preparation can be used to make beverages with improved health benefits, hence minimising environmental pollution.

Innovative applications of whey protein for sustainable dairy industry: Environmental and technological perspectives-A comprehensive review.

Industrial waste management is critical to maintaining environmental sustainability. The dairy industry (DI), as one of the major consumers of freshwater, generates substantial whey dairy effluent, which is notably rich in organic matter and thus a significant pollutant. The effluent represents environmental risks due to its high biological and chemical oxygen demands. Today, stringent government regulations, environmental laws, and heightened consumer health awareness are compelling industries to responsibly manage and reuse whey waste. Therefore, this study investigates sustainable solutions for efficiently utilizing DI waste. Employing a systematic review approach, the research reveals that innovative technologies enable the creation of renewable, high-quality, value-added food products from dairy byproducts. These innovations offer promising sustainable waste management strategies for the dairy sector, aligning with economic interests. The main objectives of the study deal with, (a) assessing the environmental impact of dairy sector waste, (b) exploring the multifaceted nutritional and health benefits inherent in cheese whey, and (c) investigating diverse biotechnological approaches to fashion value-added, eco-friendly dairy whey-based products for potential integration into various food products, and thus fostering economic sustainability. Finally, the implications of this work span theoretical considerations, practical applications, and outline future research pathways crucial for advancing the sustainable management of dairy waste.

Recent advances in eco-friendly technology for decontamination of pulp and paper mill industrial effluent: a review.

The economic development of a country directly depends upon industries. But this economic development should not be at the cost of our natural environment. A substantial amount of water is spent during paper production, creating water scarcity and generating wastewater. Therefore, the Pollution Control Board classifies this industry into red category. Water is used in different papermaking stages such as debarking, pulping or bleaching, washing, and finishing. The wastewater thus generated contains lignin and xenobiotic compounds such as resin acids, chlorinated lignin, phenols, furans, dioxins, chlorophenols, adsorbable organic halogens (AOX), extractable organic halogens (EOCs), polychlorinated biphenyls, plasticizers, and polychlorinated dibenzodioxins. Nowadays, several microorganisms are used in the detoxification of these hazardous effluents. Researchers have found that microbial degradation is the most promising treatment method to remove high biological oxygen demand (BOD) and chemical oxygen demand (COD) from wastewater. Microorganisms also remove AOX toxicity, chlorinated compounds, suspended solids, color, lignin, derivatives, etc. from the pulp and paper mill effluents. But in the current scenario, mill effluents are known to deteriorate the environment and therefore it is highly desirable to deploy advanced technologies for effluent treatment. This review summarizes the eco-friendly advanced treatment technologies for effluents generated from pulp and paper mills.

Evaluation of Kluyveromyces spp. for conversion of lactose in different types of whey from dairy processing waste into ethanol.

The processing of dairy products currently generates significant amounts of waste, particularly in the form of liquid whey. The disposal of whey poses a challenge to the environment due to its high organic content and biological oxygen demand. Whey contains lactose, soluble proteins, lipids, and minerals. While Saccharomyces cerevisiae can efficiently utilize glucose, they are unable to metabolize lactose. In contrast, Kluyveromyces spp. encode two genes, Lac12 and Lac4 that enable conversion of lactose to other by-products such as ethanol. Here, we selected five Kluyveromyces yeast inoculated into three different types of whey substrates, cheddar sweet whey, cream cheese acid whey, and yogurt acid whey that could be used to convert lactose into ethanol. We demonstrate that differences exist in ethanol production across different whey substrates inoculated with Kluyveromyces yeast. In sweet whey, K. lactis, K. lactis Y-1205 and K. lactis Y-1564 were the highest ethanol producing strains. The highest amount of ethanol produced was 24.85 ± 3.5 g/L achieved by Y-1564 in sweet whey (96.8% efficiency). K. lactis Y-1205 produced 22.39 ± 5.6 g/L ethanol in yogurt acid whey. In cream cheese acid whey, K. lactis strains produced significantly higher ethanol levels compared to S. cerevisiae and K. marxianus (p < 0.05). Outcomes from this study could provide a simple and cheap solution for small-to medium-sized dairy processing facilities to ferment lactose in whey into ethanol using lactose-consuming yeasts.

Treatment efficiency of package plants for on-site wastewater treatment in cold climates

Package plants (PP) are implemented around the world to provide on-site sanitation in areas not connected to a sewage network. The efficiency of PP has not been comprehensively studied at full scale, and the limited number of available studies have shown that their performance varies greatly. Their performance under cold climate conditions and the occurrence of micropollutants in PP effluents have not been sufficiently explored. PP are exposed to environmental factors such as low temperature, especially in cold regions with low winter temperatures and deep frost penetration, that can adversely influence the biochemical processes. The aim of this study was to investigate the treatment efficiency and possible effects of cold temperatures on PP performance, with focus on traditional contaminants (organics, solids, nutrients and indicator bacteria) and an additional assessment of micropollutants on two PP. Eleven PP hosting different treatment processes were monitored. Removal of biological oxygen demand (BOD) was high in all plants (>91%). Six out of the 11 PP provided good phosphorus removal (>71%). Small degrees of nitrification were observed in almost all the facilities, despite the low temperatures, while denitrification was only observed in two plants which achieved the highest nitrification rates (>51%) and had sludge recirculation. No strong correlation between wastewater temperature and BOD, nutrients and indicator bacteria concentration in the effluents was found. The high data variability and the effects of other process parameters as well as snow-melt water infiltration are suggested as possible reasons for the lack of correlation. However, weak negative relations between effluent concentrations and wastewater temperatures were detected in specific plants, indicating that temperature does have effects. When managed adequately, package plants can provide high BOD and phosphorus removal, but nitrogen and bacteria removal remain challenging, especially at low temperatures. Pharmaceutical compounds were detected in the effluents at concentrations within or above ranges reported for large treatment plants while phthalate ester concentrations were below commonly reported effluent concentrations.

Utilization of vegetable tannins for stabilization of collagen fibers by using supported process enzyme

Tanning is the process of treating animal skins or hides to produce leather, which is more durable and less susceptible to decomposition. The leather industry has been pushed to develop tanning systems that utilize natural products due to environmental concerns. Vegetable tanning is one of the oldest methods, but its usage is limited due to the high organic load in the effluent generated. This load is difficult to degrade and results in high biological and chemical oxygen demand. This study aimed to develop an eco-friendly tanning process for protein fibers using proteolytic enzymes. The goal was to improve the exhaustion of vegetable tannins by increasing their uptake during the tanning process. The optimized experimental process, which involved enzymatic treatment of protein fibers, resulted in an exhaustion of 97% compared to 83% in conventional vegetable tanning processes. Enzyme treatment before tanning also led to a slight improvement in hydrothermal stability, as well as slightly better physical properties of the resulting leathers compared to conventionally tanned leathers. The enzymatic process has the added benefit of reducing total solids (TS) and chemical oxygen demand (COD) loads in the identified streams by 80% and 33%, respectively.

Water Footprint Calculation, Effluent Characteristics and Pollution Impact Assessment of Leather Industry in Bangladesh

Leather processing industries consume high volumes of water and chemicals and release effluents into the environment that pollute the surface water and may cause harm to human health. Leather processing involves different wet processing stages such as soaking, liming, chrome tanning, rechroming, neutralization, fatliqouring and dyeing. The pollution generated from the leather processing stages varies in volume, nature and concentrations. Qualitative and quantitative assessments of effluents generated from different stages of leather processing can be useful to understand the stagewise and overall water pollution of leather wet processing and to design and plan pollution abatement initiatives. Water footprints (WF) can help in understanding the total water consumption and water pollution caused by the leather sector. The objectives of this research are to assess the characteristics of effluents generated from different stages of leather processing, calculate the water footprint (WF) and analyze the pollution load of the Bangladesh leather sector. To perform experimental analyses, effluent samples were collected from the following leather processing stages: soaking, liming, deliming and bating, pickling and tanning, wet back, rechroming, neutralization, retanning, dyeing and fatliqouring from four leather processing factories. The key pollution indicating parameters, such as pH, chemical oxygen demand (COD), biological oxygen demand (BOD), total dissolved solid (TDS) and total suspended solid (TSS) of the effluent samples were analyzed. The experimental study showed that almost 52% effluents generate from beam house and tan yard operations, and about 48% effluents generate from post tanning operations. Due to the presence of high amounts of salt, insecticides and bactericides, the effluent generated from the soaking stage contains high BOD and TDS. On the other hand, effluent generated from liming contains the highest amounts of BOD, COD, TDS, and TSS. The reduction or segregation of soaking and liming effluents will be effective in improving the environmental performance of the wet processing of leather. To assess the total water footprint of the leather sector, the water footprint of feed crops and raw hides were calculated, along with the water footprint of the leather processing stages. The water footprints of bovine and ovine crust leather were found to be 34,000 m3/ton and 17,300 m3/ton, respectively. The blue water footprint is higher in soaking, liming and finishing. The green water footprint of leather is mainly contributed by feed crops of farming animals. The grey water footprint was found higher in the soaking, liming, fatliqouring and dyeing stages. About 97% of the water footprints of tanneries are contributed by the wet processing stages. The grey water footprint is the most significant part of the total water footprint of the leather sector, which indicates the impact of high water pollution by the leather processing stages. This study can help to understand the overall scenario of water consumption and water pollution caused by the leather sector in Bangladesh. This study can also be useful in designing sustainable leather products by reducing the total water footprint per unit of leather goods. The systematic approach of this study could be useful for other countries in leather processing.

Characterization of P(3HB) from untreated raw palm oil mill effluent using Azotobacter vinelandii ΔAvin_16040 lacking S-layer protein

The production of poly(3-hydroxybutyrate) [P(3HB)] from untreated raw palm oil mill effluent (urPOME), the first wastewater discharge from crude palm oil extraction, is discussed. The mutant strain Azotobacter vinelandii ΔAvin_16040, which lacks the S-layer protein but has a better P(3HB) synthesis capability than the wild type strain ATCC 12,837, was chosen for this study. UrPOME substrate, with high biological oxygen demand (BOD), chemical oxygen demand (COD) and suspended solids, was used without pre-treatment. DSMZ-Azotobacter medium which was devoid of laboratory sugar(s) was used as the basal medium (BaM). Initially, Azotobacter vinelandii ΔAvin_16040 generated 325.5, 1496.3, and 1465.7mg L-1 of P(3HB) from BaM with 20% urPOME, 2BaM with 20% urPOME and 20g L-1 sucrose, and 2BaM with 20% urPOME and 2mL L-1 glycerol, respectively. P(3HB) generation was enhanced by nearly tenfold using statistical optimization, resulting in 13.9g L-1. Moreover, the optimization reduced the compositions of mineral salts and sugar in the medium by 48 and 97%, respectively. The urPOME-based P(3HB) product developed a yellow coloration most possibly attributed to the aromatic phenolics content in urPOME. Despite the fact that both were synthesised by ΔAvin_16040, thin films of urPOME-based P(3HB) had superior crystallinity and tensile strength than P(3HB) produced only on sucrose. When treated with 10 and 50kGy of electron beam irradiation, these P(3HB) scissioned to half and one-tenth of their original molecular weights, respectively, and these cleavaged products could serve as useful base units for specific polymer structure construction.

Diversity of hexavalent chromium-reducing bacteria and physicochemical properties of the Kanpur tannery wastewater

The tannery effluent sample was collected from a tannery located in Jajmau area of Kanpur, India and subjected to physicochemical analysis. The tannery effluent was brownish in color with a foul odor. It was alkaline in nature and characterized by high biological oxygen demand (BOD), chemical oxygen demand (COD), total solids (TS), total dissolved solids (TDS) and high amounts of chromium. Total eighteen chromium resistant bacteria were isolated from the tannery effluent sample. Based on the 16S rRNA gene sequencing and phylogenetic analysis, these eighteen bacteria belong to seven different genera including Bacillus, Pseudomonas, Kocuria, Cellulosimicrbium, Klebsiella, Microbacterium, Brucella. The members of genus Bacillus constitute 28% of total chromium transforming isolates; followed by members of genus Microbacterium (17%) Brucella (17%), Pseudomonas (11%), Cellulosimicrobium (11%), Kocuria (11%) and Klebsiella (5%). Furthermore, all eighteen bacteria were screened for their ability to reduce hexavalent chromium with increasing concentrations (600–1200 ppm) of potassium dichromate. Results showed that one bacterium, Bacillus licheniformis strain KNP exhibited hexavalent chromium reduction up to concentrations of 1000 ppm. This bacterium was selected for further study.

A study on microbiota isolated from olive mill wastewater disposal ponds, with emphasis on filamentous fungi and their biodegradative potential in North Sinai Governorate, Egypt

The microbial composition of olive mill wastewater (OMWW) from six disposal ponds at three localities in North Sinai Governorate, Egypt has been studied. Such OMWW samples contained a variable (but high) number of bacteria, yeasts, and mold. Eighty-one isolates related to 9 bacterial species were recovered, and seven common bacterial species were isolated from Bir al Abd, Al-Arish, and Rafah sites sources namely Enterococcus faecalis, Escherichia coli, Bacillus cereus, B. subtilis, Micrococcus luteus, Pseudomonas aeruginosa, and Klebsiella pneumonia. In addition to these species, Vibrio cholerae and Shigella species were isolated from the Bir al Abd site. One hundred and twenty isolates related to 13 fungal species were recovered. Seven members of different fungal genera (Aspergillus, Penicillium, Fusarium, Paecilomyces, Alternaria, Chaetomium, and Rhizopus) were recorded. Four genera were widely distributed, and they were able to grow efficiently in undiluted OMWW as a sole source of nutrients. Strains of Aspergillus, Penicillium, Fusarium, and Paecilomyces showed a marked capacity for OMWW detoxification. The physicochemical studies further revealed the presence of relatively low levels of sodium, potassium, calcium, magnesium, and iron. Nitrate concentration was relatively high, 70.13 mg/L. The biological oxygen demand (BOD) and the chemical oxygen demand (COD) recorded high values that ranged between 2210-2270 mg/L and 22760-22800 mg/L, respectively. High BOD and COD values are important indicators of high organic and inorganic components of OMWW and possible negative environmental consequences. The presence of fungal and bacterial species implied possible degradation of the effluent.

Impact of textile dyes on human health and bioremediation of textile industry effluent using microorganisms: current status and future prospects

Environmental contamination brought on by the discharge of wastewater from textile industries is a growing concern on a global scale. Textile industries produce a huge quantity of effluents containing a myriad of chemicals, mostly dyes. The discharge of such effluents into the aquatic environment results in pollution that adversely affects aquatic organisms. Synthetic dyes are complex aromatic chemical structures with carcinogenic and mutagenic properties in addition to high biological oxygen demand (BOD) and chemical oxygen demand (COD). This complex aromatic structure resists degradation by conventional techniques. The bioremediation approach is the biological clean-up of toxic contaminants from industrial effluents. Biological treatment methods produce less or no sludge and are cost-effective, efficient, and eco-friendly. Microorganisms, mostly microalgae and bacteria, and, in some instances, fungi, yeast, and enzymes decolorize textile dye compounds into simple, non-toxic chemical compounds. Following a thorough review of the literature, we are persuaded that microalgae and bacteria might be one of the potential decolorizing agents substituting for most other biological organisms in wastewater treatment. This article presents extensive literature information on textile dyes, their classification, the toxicity of dyes, and the bioremediation of toxic textile industry effluent utilizing microalgae and bacteria. Additionally, it combines data on factors influencing textile dye bioremediation, and a few suggestions for future research are proposed.

Major concerns of surface water quality in south-west coastal regions of Vietnamese Mekong Delta

This study aimed to appraise seasonal variations in surface water quality on the coasts of Southwestern Vietnam using entropy-weighted water quality index (EWQI) and multivariate statistics: cluster analysis (CA), principal component analysis (PCA), and discriminant analysis (DA). Forty-nine samples monitored in Kien Giang province during the rainy and dry seasons were analysed for 16 physiochemical and biological parameters. Compared to the Vietnamese standard, surface water quality in the study areas was contaminated with organic matter (high biological oxygen demand and chemical oxygen demand), nutrients (high ammonium (NH4+), nitrite, and orthophosphate), total suspended solids (TSS), iron (Fe), and coliform. Seasonal variations in surface water quality in the coastal regions were observed. TSS, organic matter and microbial problems in water bodies tend to be more serious in the rainy seasons due to an increase in water flow containing pollutants from upstream and wastes from regional human activities. Meanwhile, the salinity in the dry season (0–32‰) was greatly higher, which caused only 10% of samples to be suitable for irrigation. CA extracted 11 and 13 clusters from 49 locations in the dry and rainy seasons, respectively. Five principal components obtained from PCA can explain 74 and 70% of total water quality variations in dry and rainy seasons, respectively. Moreover, the results of PCA suggested that natural factors (hydrological regimes, temperature, rainfall, sea-level rise) and human sources (domestic, agriculture, industry, and tourism) are accountable for these fluctuations. DA extracted 7 parameters (pH, TSS, salinity, Fe, nitrate, NH4+, and chloride) for leading the difference in water quality, with 88% of correct assignation. EWQI revealed that about 66% of total samples were classified as a very bad quality for drinking in the dry season. However, this ratio declined to 59% in the rainy season. Although the surface water quality was slightly improved during the rainy season, organic matter and microbial pollution need to be concerned. The findings of this study can provide insights into seasonal variations in surface water with the application of multivariate statistics and EWQI, which could support policymakers in developing water management strategies.

Treatment of slaughterhouse industry wastewater with ultrafiltration membrane and evaluation with life cycle analysis

Slaughterhouse wastewater is one of the most produced industrial wastewater in the world and has a high pollution potential, and this wastewater can cause a high level of polluting effect when it is given directly to river beds or sewage systems. Wastewater contains proteins, fats, carbohydrates in the treatment of blood, skin and feathers, which results in much higher biological oxygen demand (BOD) and chemical oxygen content (COD). The possibility of using ultrafiltration for slaughterhouse wastewater treatment was investigated. The results showed that ultrafiltration can be an efficient purification method. COD and BOD5 remova lefficiency is around 96% and 95%. In addition to these results, the Life Cycle Analysis (LCA) of the ultrafiltration system was also carried out. Accordingly, the effects of ultrafiltration system on human health, ecosystem quality, climate change and resources were calculated as 0,00000046 Disability-Adjusted Life Years (DALY), 0,134 PDFxm2yr, 0,336 kg CO2 eq and 6,937 MJ respectively. As a result of the study, it is thought that slaughterhouse wastewater can be used as irrigation water after passing through the ultrafiltration membrane due to the high content of N and P.

Butanol production from Thai traditional beverage (Sato) factory wastewater using newly isolated Clostridium beijerinckii CUEA02

Sato, a Thai traditional beverage, wastewater (STW) contains residual rice constituents with high chemical and biological oxygen demands, and so its disposal is an environmental problem. To solve this, the potential of STW for butanol production, which has never been evaluated for use in ABE fermentation, is reported. Clostridium beijerinckii CUEA02, the strain producing the highest butanol level in this study, was isolated from natural sources in Thailand. Isolate CUEA02 was closely related to C. beijerinckii with an average nucleotide identity of 95.14% and could grow and produce butanol from various carbon sources. The butanol production was 8.32 ± 0.08 g/L in flask fermentation under an initial pH of 6.5, 35 °C, 10% (v/v) inoculum size, and 50 g/L of glucose. To evaluate the potential of STW, it was diluted 0.1x, 0.2x, 0.3x, and 0.4x for ABE production by CUEA02, with the 0.1x dilution giving the highest butanol yield (0.23 g/g). To improve the butanol production, the initial pH was adjusted from 4.75 to 6.5, resulting in a 2.13-fold enhanced butanol yield (0.49 g/g). Moreover, the addition of yeast extract at 2 g/L increased the butanol production by up to 29% in STW using C. beijerinckii CUEA02.

Cheese Whey as a Potential Feedstock for Producing Renewable Biofuels: A Review

Agro-industrial residues such as bagasse, pomace, municipal residues, vinasse and cheese whey are an environmental problem around the world, mainly due to the huge volumes that are generated because of the food production to satisfy the nutritional needs of the growing world population. Among the above residues, cheese whey has gained special attention because of its high production with a worldwide production of 160 million tons per year. Most of it is discarded in water bodies and land causing damage to the environment due to the high biological oxygen demand caused by its organic matter load. The environmental regulations in developing countries have motivated the development of new processes to treat transform cheese whey into added-value products such as food supplements, cattle feed and food additives. In addition, during the last decade, several processes and technologies have been developed to produce bioenergy through the biotechnological process using cheese whey as a potential feedstock. This review discusses the production of bioethanol, biohydrogen, biomethane and microbial lipid-biodiesel production using cheese whey as a potential substrate.

Impact of varying hydraulic retention time for treating distillery effluent in activated sludge system to combat the environmental and health hazards

Ethanol-distilleries are the key supporter to the world's economy, but these are moreover one of the major sources of environmental pollution that can impact the human heath if the effluents are not treated in proper manners. Distillery effluents with high biological oxygen demand (BOD) and chemical oxygen demand (COD) contains toxic chemicals which are reported to be of carcinogenic and mutagenic in nature. One of the widely used technology for the distillery wastewater treatment is based on up-flow anaerobic sludge blanket (UASB) technology along with activated sludge process. This technology has fulfilled a need for high efficiency treatment of wastes from various distilleries. With the increasing demands of distillery units and strict guidelines by government agencies for the environment protection, more efforts are required to achieve the zero liquid discharge (ZLD). The research reported in this paper is an effort to perform the in-situ study for evaluating the impact of varying retention times on the efficiency of the condensate Polishing Unit (CPU) based on UASB technology along with activated sludge process for ZLD. The primary objective was to determine pH, BOD and COD after increasing the HRTs in the aeration tank.

WASTEWATER QUALITY AND POLLUTION LOAD OF EACH STAGE IN TEMPEH PRODUCTION

Aim: This study is purpose to understand the chemical and physical characteristics and pollution load in each step of tempeh wastewater: washing, boiling, soaking and mixing. Tempeh is traditional food from soybean fermentation. Tempeh has a lot of healthy contents as protein and vitamin. However, wastewater from tempeh production is discharge to river directly which considered as environmentally damaging. However, the characteristics of wastewater from tempeh production and its level of environmental impacts to environment are limitedly studied. Methodology and Results: Tempeh wastewater was analyzed in chemical and physical parameters. Chemical characteristics analyzed are pH, Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD). pH was measured using pH meter, BOD using SNI 6989.72:2009 method and COD using SNI 6989.2:2019 method. The physical parameter analyzed is Total Suspended Solid (TSS) and analyzed using SNI 6989.3: 2019 method. Pollution load calculated by deviation maximum pollution load and pollution load existing. Result of this study findings indicated that the highest BOD 299.40 mg/L and COD 540.66 mg/L was found in soaking step compared to other steps in tempeh production. Highest TSS 655.20 mg/L was found in boiling step. The pH values in all steps were acidic 4 and 5. Allocation Pollution load of: TSS overall exceeded the capacity, BOD and COD overall exceeded the capacity except in washing step (BOD 304.39 kg/day and COD 857.78 kg/day). Conclusion, significance and impact of study: The Highest TSS of tempeh wastewater processes was in boiling step while the highest organic matter was detected in soaking. Further for whole pH were acidic and exceeded the standard. Allocation of pollution load for TSS, BOD and COD exceed the standard except for BOD and COD in washing waste. Overall tempeh wastewater needs treatment to prevent river pollution.

Dampak pariwisata terhadap pencemaran air danau batur kabupaten bangli

This study aims to determine the impact of tourism on water pollution in Lake Batur. This study uses a qualitative descriptive analysis method. The samples taken include 5 points on Lake Batur which represent tourism locations on Lake Batur, namely the pier, restaurants, tourist attractions in Terunyan Village, hot spring attractions and the middle of the lake. Collecting data using observation methods, laboratory test methods and documentation studies. The research begins with direct observation to 3 key informants who can represent the condition of tourism in Lake Batur, namely the surrounding community, business and visitors. Furthermore, water sampling in Lake Batur and continued with laboratory testing for parameters of pH, biological oxygen demand (BOD), chemical oxygen demand (COD), oil and fat. Next is a documentation study on the situation and condition of Lake Batur and the last is collecting secondary data as supporting data. Furthermore, the data were analyzed de qualitatively to determine the impact of tourism potential on the water quality of Lake Batur.&#x0D; Based on the results of laboratory testing, Lake Batur is polluted in the restaurant and pier area. The restaurant area is characterized by high BOD parameters, while the pier area is characterized by high COD parameters. Based on this, it can be seen that tourism has an impact on increasing the value of pollutants in the waters of Lake Batur. Berdasarkan hasil pengujian laboratorium Danau Batur mengalami pencemaran pada daerah restoran dan dermaga. Pada daerah restoran ditandai dengan tingginya parameter BOD sedangkan daerah dermaga ditandai dengan tingginya parameter COD. Berdasarkan hal tersebut dapat dilihat bahwa pariwisata memberikan dampak terhadap peningkatan nilai pencemar pada perairan Danau Batur