Average BOD Research Articles

Microbial and Physicochemical Qualities of Septic Tank Wastewater: An Evaluation.

The physicochemical and microbial qualities of septic tank effluent samples from households within the study area were evaluated. Three replicate samples from Locations A, B, and C representing Agbor, Benin City, and Sapele regions of Delta and Edo States, Nigeria were collected from both the inlet tank (raw sewage) and the outlet chamber (semi-treated sewage) for physicochemical and microbiological analyses using standard methods. Results of the physicochemical analyses showed that pH values ranged from 6.5 – 7.7 across locations and in both the raw and semi-treated samples. Electrical conductivity (EC), Total suspended solid (TSS) and BOD was significantly higher (p>0.05) in the raw sewage (RS) than in the semi-treated (SS), while DO was higher (p>0.05) in the SS in all three locations sampled. Microbial analysis shows that total heterotrophic bacteria (THB) was highest in the RS in two locations. Microbial isolates from wastewater samples included Staphylococcus aureus, Proteus mirabilis, Escherichia coli, Pseudomonas aeruginosa, and Aspergillus niger. DO was low at an average of 3.20 and 3.73 mg/L in both chambers of the septic tank. Average BOD5 of 59.4 and 42.8 mg/L and COD average of 206.8 and 153.2 mg/L were reported for the RS and SS chambers. 0.3 was the value of the ratio of BOD5/COD for the RS and SS in the study. This infers that biodegradation was slow and inefficient in the septic tank system, and that modification of the design is recommended to increase retention time in the RS chamber

POLLUTION LOAD (TSS, DO, BOD, AND COD) AND THE KALIYASA RIVER POLLUTION INDEX IN CILACAP DISTRICTS

The Kaliyasa River was one of the many rivers in Cilacap Country. The River Kaliyasa is physically close to populations and industries that produce a wide range of products, making it a great potential for receiving both domestic and industrial wastes. The study was carried out in Oktober-November 2020 with four sample viewing points before the wastewater output, the wastewater outlet, at exactly the time of the wastewater output, and after the wastewater output. The sampling was done three times every two weeks. Based on this study, calculations indicate that the average value of the pollution load from the wastewater outlet was staggering at 32.661,60 kg/day. The average price of the pollution burden from the station after the wastewater output was produced a value of 15.945,92 kg/day. Average TSS, DO, BOD, and COD variables have already surpassed the second of class river quality. The Kaliyasa River pollution index is obtained that according to TSS, DO, BOD, and COD variables measured indicate IP Numbers in level 6, which include 6,16 of moderate pollutants. Keywords: Comparisons with Water Quality, Load Of River Pollution, Pollution Index

Macrozoobenthos Community Structure in Situ Cileunca, Pangalengan District, Bandung Regency, West Java

This research aims to determine the structure of the macrozoobenthos community which includes variety, diversity, uniformity, coefficient of similarity and the Family Biotic Index (FBI) macrozoobenthos as well as the physical and chemical parameters of the waters and to determine the pollution status of Situ Cileunca waters. The research was conducted in Situ Cileunca, Bandung Regency, West Java from January to February 2021. The research method used a survey method. The method used in data collection is purposive sampling by determining 5 stations and 4 times. Data analysis in this research uses descriptive analysis. The results showed that the lowest average Biochemical Oxygen Demand (BOD5) value was found at station 4 of 8.90 ±4.92 mg/L and the highest average BOD5 value was found at station 5 of 12.99 ± 6.60 mg/L. There are three species of macrozoobenthos that live in the waters of Situ Cileunca, namely Pomacea canaliculata, Filopaludina javanica and Anodonta woodiana. Macrozoobenthos abundance ranges from 400 - 704 ind/m2. The diversity index of macrozoobenthos is included in the low category, ranging from 0.17 to 0.28. The uniformity value ranged from 0.36 - 0.59 which was classified as moderate in all including except at station 4 which was classified as low. The lowest average similarity coefficient was found between stations 3 and 5 was 0.13 and the highest average similarity coefficient between stations 4 and 5 was 0.30. The index value of the FBI macrozoobenthos ranged from 6.05 to 6.18 with a rather poor category. The pollution status of Situ Cileunca is moderately polluted because the BOD5 value is categorized as moderately polluted, the diversity (H') is classified as heavily polluted and the FBI value is in the rather poor category.

On-site domestic wastewater treatment system using shredded waste plastic bottles as biofilter media: Pilot-scale study on effluent standards in Bhutan

In this study, a 1000 L/d capacity one-off on-site wastewater treatment system was operated for over a year as a pilot alternative to the conventional on-site treatment as currently used in urban Bhutan. An up-flow anaerobic sludge blanket (UASB) was used for blackwater treatment (to replace “septic tank followed by an anaerobic biofilter (ABF) (to replace soak pits) for the treatment of a mixture of greywater and UASB effluent. Shredded waste plastic bottles were used as the novel biofilter media in the ABF. During a yearlong operation, the pilot system produced a final treated effluent from ABF with average BOD5 28 mg/L, COD 38 mg/L, TSS 85 mg/L and 5 log units of Escherichia coli. These effluents met three out of four of the national effluent discharge limits of Bhutan, but unsuccessful to meet the Escherichia coli standard over a yearlong operation. Further, process optimisation may enable more significant Escherichia coli removal. An economic analysis indicates that the total unit cost (capital and operating expenditures) of this alternative wastewater treatment system for more than 50 users range between USD 0.27–0.37/person/month comparable to USD 0.29–0.42/person/month for the current predominant on-site system, i.e., “septic tanks”. This pilot study, therefore, indicates that this wastewater treatment system using shredded waste plastic biofilter media has high potential to replace the current conventional treatment, i.e., “septic tanks”, which are often overloaded with greywater and discharging effluents which does not meet the national standards.

Application of Water Quality Evaluation in the Cotai City Ecological Reserve in Macau: Taking the Single Factor Index Evaluation Method as an Example

This paper uses a single-factor index evaluation method to evaluate the water quality of the Cotai Ecological Reserve in Macau. Water quality evaluation is a necessary way to rationally renovate the water environment. In this paper, the average dissolved oxygen, average total nitrogen, average total phosphorus and BOD5 in the water environment of the ecological protection zone are used as the evaluation indicators of water quality. The analysis results show that the average dissolved oxygen index can maintain the requirements of water function zoning throughout the year. The average total nitrogen and BOD5 index exceeded the standard seriously. Therefore, the water quality index of the ecological zone needs to be improved.

Effect of Media on Treatment of Settled Domestic Sewage Using Hybridized Anaerobic Baffled Reactors.(Dept.C)

This research work aimed at obtaining a low cost sustainable technology for domestic wastewater treatment for Egyptian rural areas. To make this come through, a high rate hybirdized anaerobic baffled reactor (HABR) was pilot tested for a period of about 18 months in order to assess the state of art and the technical and economic efficiency of this system. This pilot reactor consisted of four reactors with different media (HABR1, HABR2, HABR3 and HABR4) were constructed and each reactor had a total volume of 800 liters and consists of four compartments. Plastic media and gravel were used and had specific surface area of 100 and 80 m2/m3respectively. The average influent COD concentration was about 300 mg/1. The overall HRTs tested were 3.5, 2.5, 1.0 and 0.5 days with average influent organic loadings in the range from 0.05 to 0.25 Kg BOD5/m3.day. High substrate removal rates can be achieved in a HABR fed with low substrate levels of only 300 mg/lit of COD. At an HRT of 3.5 days, HABR) with plastic media gave an average BOD5 removal rate of 79% with an effluent of 25 mg/lit. This was the highest removal value recorded as the other reactors HABR2, HABR3 and HABR4 gave 60.5%, 71.5% and 75.6% respectively for the same HRT, In a likewise manner, the COD removal rates recorded at the same HRT were 85.7%, 80%, 83.3% and 85.7% respectively. Suspended solids removal rates were the highest and recorded a value of 90.3% for a HRT of 3.5 days for HABR1. At the same HRT the removal rates for HABR2, HABR3 and HABR4 were 76.8%, 86.5% and 89% respectively. For HABRI the HRT of 0.5 days. The highest COD value recorded was at a HRT of 0.5 days BODs removal rates dropped from 79% at a HRT of 3.5 days to about 50.5% at a HRT of 0.5 days. This was also the case with the other three reactors and the lowest removal rate recorded was 33.7% for HABR2 at for HABR2 with a value of 101.2 mg/lit. While the highest SS value recorded was 72.4 mg/lit with a percentage removal of 58.8% for HABR3 at a HRT of 0.5 days. This system provides potential attractive possibilities for application in small communities with a population of less than 5000 capita.

Antimicrobial and coagulation potential of Moringa oleifera seed powder coupled with sand filtration for treatment of bath wastewater from public senior high schools in Ghana

The use of natural plant extracts for treatment of water in some parts of the world has been recorded throughout human history. An example is the use of Moringa oleifera in water purification due to its coagulation properties. However, the efficiency of the treatment systems largely depends on the design of the system and its operation. The aim of this study was to investigate the efficiency of Moringa oleifera seed powder coupled with sand filtration in treating greywater from public senior high schools in the Bolgatanga Municipality and Kasena Nankana West District in the Upper East Region of Ghana. Microbial and physico-chemical properties of greywater collected monthly from the senior high schools was analyzed. Moringa oleifera seed powder was added to raw greywater and then filtered through a sand filter bed. Physico-chemical and microbial parameters of the treated greywater were then analyzed. Mean turbidity, TDS, TSS, T. phosphate and T. nitrogen of the raw greywater was 312.5 ± 76.58 NTU, 445.6 ± 86.77 mg/L, 160.0 ± 28.68 mg/L, 89.3 ± 7.76 mg/L and 30.19 ± 3.63 mg/L respectively whiles average BOD, COD, E. coli and Total coliform were 1032.5 ± 252.40 mg/L, 1736.0 ± 431.59 mg/L, 84.75 x 106 ± 94.01 x 106 N/100ml and 184.25 x 10s ± 181 x 106 N/100ml respectively. After treatment, there was percentage reduction in turbidity (98.14%), TDS (72.7%), TSS (98.9%), T. phosphate (75.64%), T. nitrogen (43.11%), Total coliform and E. coli (>99%) were recorded. Turbidity was 0.1 NTU and did not meet the WHO standard for drinking water but T. hardness, E. coli and pH was in line with the WHO limit for drinking water. However, BOD increased, and this could be attributed to the significant protein content in the seed of Moringa oleifera. Moringa oleifera seed powder coupled with sand filtration demonstrated the antimicrobial and coagulative potential as turbidity and E. coli of the raw bath greywater from the senior high schools reduced by >98% and >99.99% respectively after treatment.

The Ability of Sagittaria lancifolia as Phytoremediator on Detergent Solution

Sagittaria lancifolia is a plant that can be used as a phytoremediator. This study aimed to determine the effect of phytoremediation in various concentrations of a detergent solution, a different detention time and interaction both on levels of LAS, BOD, leaf morphology and chlorophyll content. Method using an experimental with randomized block design with three factors of each treatment with three replications. Analysis of data using ANOVA two directions and continued test of Duncan. The results showed that the average percentage reduction in the levels of LAS on the most optimal planting medium is shown at a concentration of 75 ppm detention time of 14 days at 81.53%, the average BOD is best contained at a concentration of 10 ppm to 14 days detention time of 25.55 mg/l and lowest average chlorophyll content was shown at a concentration of 75 ppm detention time of 14 days amounted to 14.433 mg/l. Chlorosis and necrosis highest concentration of 75 ppm is shown in 14-day detention time.

Water sustainability using pond-in-pond wastewater treatment system: Case studies

Wastewater is an easily accessible but highly underutilized resource that could meet irrigation needs while conserving freshwater for future generations and is increasingly recognized as an essential and economical strategy in areas with water scarcity. This paper presents case studies on the Pond-In-Pond (PIP) configuration where PIP is an integration of two types of pond – anaerobic and aerobic – and consists of a deeper inner section entirely submerged within the outer pond. Performance data from existing PIP, or PIP-like systems dated back to 1960s’, were collected and analyzed; and the results from the PIP systems investigated resulted in an average BOD removal of over 80 % with a deviation of less than 10 %. Consequently, the PIP unit alone ensured a level of treatment required for effluent reuse in crop irrigation for typical municipal wastewater with influent BOD in the range of 200–300 mg L−1. Moreover, the combination of PIP with other processes in a treatment system has the capability of treating high-strength wastewater for other uses such as aquaculture, fishery, and others–including stream discharge. The PIP is a potentially viable and sustainable technology for low-cost wastewater treatment especially for reuse purposes due to the savings in capital costs, operations and maintenance costs, and revenue from reclamation of the effluent.

Multiple draft tubes airlift loop membrane bioreactor as an efficient system for acidic 7-amino cephalosporanic acid (7-ACA) wastewater treatment

In this study, a lab-scale multiple draft tubes airlift loop membrane bioreactor (Mt-ALMBR) was used for treating acidic 7-amino cephalosporanic acid (7-ACA) wastewater under different pHs (3.54–6.20) and hydraulic retention time (HRT) (48 h, 36 h, 24 h and 16 h). During about 200 days operation, under HRT of 48 h and pH condition about 6.0, the optimum average COD and BOD5 removal rates were reach to 84.4 ± 2.1% and 94.9 ± 0.8%, and the highest 7-ACA removal rate also observed as 77.6%. Biodegradation, membrane rejection, hydrolysis and sludge adsorption were the four main pathways of 7-ACA removal. With the increase of pH, biodegradation, membrane rejection and hydrolysis had significant positive impacts on 7-ACA removal, while adsorption had a negative impact. Moreover, mathematical models for 7-ACA removal rate and pH were calculated to guide the operation of Mt-ALMBR. Biodegradation was the main pathway to remove 7-ACA when pH was >4.17.

Olive mill wastewater (OMW) production in the province of Al-Hoceima (Morocco) and their physico-chemical characterization by mill types

The purpose of the present work is to establish a state of the production of waste from olive oil mills in the province of Al-Hoceima and to evaluate the physico-chemical quality of three different types of mills (traditional mills, semi-modern, and modern units) used in the region. The results of the physico-chemical analysis of OMW for these three mill types showed an acidic pH with an average value of 4.7. They are also rich in organic matter with an average COD of 159.57 g of O2/L, including a remarkable value for the traditional mill on the order of 213.44 g of O2/L, and an average BOD5 on the order of 70.33 g of O2/L. Electrical conductivity, suspended solids, oil grass, polyphenols and chloride content were exhibited average values of 17.34 ms/cm, 6.14 g/L, 0.93 g/L, 4.3 g/L, and 6.1 g cl−/L, respectively. We also assessed the degree of metal pollution of the OMW; the results obtained showed a total absence of Cadmium and Zinc with a few traces of Nickel in all units, and Lead found only in the semi-modern units.

Influence of Landfill Leachate on Organic Matter Removal in Activated Sludge and Activated Sludge with Carrier Processes

Abstract This study assessed the performance of two pilot units, a conventional activated sludge (CAS) and an Integrated Fixed-Film Activated Sludge (IAS), in the treatment of leachate from sanitary landfill combined with domestic sewage, with the aim of removing organic substances. In order to assess the possible impacts on treatment, three experimental phases were designed using influent leachate contributions of 5%, 10%, and 20% of the total BOD load. Overall, the results showed that no significant changes in the behavior of biological processes. The IAS unit presented average BOD removal efficiencies of above 88%, 87% and 80% for the three leachate load contributions of 5%, 10% and 20% studied. The CAS unit presented lower average efficiency with a 5% leachate contribution (64%), but displayed a similar performance to the IAS unit in the other phases (82% and 80%); similar quantitative aspects were observed for both treatment processes with regards to biomass composition analysis. The kinetic coefficients related to heterotrophic metabolism did not indicate negative effects on treatment efficiency as a result of the increase in leachate addition, with values of 2.8; 2.8 and 2.7 d-1 obtained respectively for each phase with the CAS unit, and 2.0; 1.5 and 1.6 d-1 with the IAS unit, representing similar values to those found in the literature (1.5 a 5.0 d-1). The results reinforced the conclusion that the leachate load introduced did not cause inhibition or significant alterations to heterotrophic metabolism, and, therefore, to the removal of organic matter.

Appraisal of suspended growth process for treatment of mixture of simulated petroleum, textile, domestic, agriculture and pharmaceutical wastewater

ABSTRACT The unrestricted discharge of domestic and industrial wastewaters along with agricultural runoff water into the environment as mixed-wastewater pose serious threat to freshwater resources in many countries. Mixed-wastewater pollution is a common phenomenon in the developing countries as the technologies to treat the individual waste streams at source are lacking due to high operational and maintenance costs. Therefore, the need to explore the potential of the suspended growth process which is a well-established process technology for biological wastewater treatment is the focus of this paper. Different wastewater constituents: representing domestic, pharmaceutical, textile, petroleum, and agricultural runoff were synthesized as a representative of mixed-wastewater and treated in two semi-continuous bioreactors (R1 & R2) operated at constant operating conditions, namely MLSS (mg/L): 4640-R1, 4440-R2, SRT: 21-d, HRT: 48–72 h, and uncontrolled pH. The system attained stable condition in day 97, with average COD, BOD and TSS reduction as 84.5%, 86.2%, and 72.2% for R1; and 85.1%, 87.9%, and 75.1% for R2, respectively. Phosphate removal on average was by 74.3% in R1 and 76.6% in R2, while average nitrification achieved in systems 1 and 2 were 56.8% and 54.7%, respectively. The biological treatment system has shown potential for improving the quality of mixed-wastewater to the state where reuse may be considered and tertiary treatment can be employed to polish the effluent quality.

Performance Comparison of Conventional and Modified Upflow Anaerobic Sludge Blanket (UASB) Reactors Treating High-Strength Cattle Slaughterhouse Wastewater

Cattle slaughterhouse wastewater (CSWW) with an average chemical oxygen demand (COD) and biochemical oxygen demand of 32,000 mg/L and 17,000 mg/L, respectively, can cause a severe environmental hazard if discharged untreated. Conventional upflow anaerobic sludge blanket (UASB) reactor is used in the treatment of slaughterhouse wastewater to meet the discharge standard limit of wastewater discharge set by the Department of Environment Malaysia (DOE). However, at higher loading rates the conventional systems are characterized by slow-growing microorganism resulting in long startup period, surface scum formation, and sludge washout. In this work, the performance of two laboratory scale (12 L) conventional (R1) and modified (R2) UASB reactors treating CSWW at mesophilic (36 ± 1 °C) condition were investigated. Both reactors were subjected to increasing organic loading rate (OLR) from 1.75 to 32 g L−1 day−1. The average COD, BOD5, and TSS removal efficiencies were ˃90%, at an OLR between 1.75 to 5 g L−1 day−1. The study revealed that R1 drastically reduced to 50, 53, and 43% with increasing OLR until 16 g L−1 day−1, whereas R2 maintained 76, 77, and 88% respectively, under the same OLR. Sign of reactor instability was very much pronounced in R1, showing poorly active Methanosaeta spp., whereas R2 showed a predominantly active Methanosarcina spp.

Advanced treatment of sewage by membrane bioreactor associate with genetically engineered autotrophic nitrifying bacteria

This study introduced a process of MBR combing with genetically engineered bacteria of expressing nirs and ppk genes (GEB-Nirs/PPK) for advanced treatment of sewage in scenic area. An industrial scale application was staged anaerobic digestion, aerobic digestion. Over more than 150 days of continuous operation, TMP in this system was less than 0.18 bar. With a membrane flux of 6.48 m3/h, TMP remained below 0.2 bar and effluent remained above 70 m3 during continuous operation. Average COD and BOD removals averaged 94.2% and 93.6%, and were obtained with average effluent COD and BOD below 10.4 mg/L and 4.2 mg/L, respectively. The TN and TP removals averaged 98.8% and 94.3%, and never higher than 3.2 mg/L and 0.2 mg/L, respectively, in the processing system. In conclusion, these results indicate that the process of MBR associate with genetically engineered autotrophic nitrifying bacteria is of high-efficiency for advanced treatment of sewage.

Comprehensive evaluation of water quality status for entire stretch of Yamuna River, India.

This study represented the first comprehensive assessment of the physicochemical water quality status of the entire Yamuna River stretch in India. The upper zone had "excellent-to-good" water quality index (WQI) with mean 5-day biochemical oxygen demand (BOD5) values of 2.1 and 2.4mg/L during monsoon and non-monsoon, respectively. The middle region was described by "poor-to-marginal" WQI with average BOD5 values of 13.1mg/L (monsoon) and 32.3mg/L (non-monsoon). The low WQI observations at the midstream region were due to the negative impact of two major drains, namely Najafgarh and Shahdara, that carry partially treated effluents from industrial units. Further, BOD5 decreased to 1.9mg/L (monsoon) and 1.8mg/L (non-monsoon) in the lower zone, and the WQI values improved to "good" and "excellent". The dilution and depuration effects of the Chambal, Sindh, Betwa, and Ken Rivers recovered the environmental conditions in downstream stations. The oxygen sag curve complied with the water quality status along the river stretch. Based on the principal component analysis, the Yamuna River was strongly influenced by dissolved mineral salts originating from atmospheric deposition, weathering of soils and rocks, and application of deicing chemicals and landfills. Moreover, organic and nutrient substances and biological activities resulting from the discharge of sewage, and the utilization of fertilizers in agriculture, were the second contributors to pollution. The statistical techniques employed in this work could be beneficial for decision-makers (government and stakeholders) to identify the pollution sources/factors and to determine the viability of water bodies for domestic applications.

Performance of full-scale coagulation-flocculation/DAF as a pre-treatment technology for biodegradability enhancement of high strength wastepaper-recycling wastewater.

Paper mill wastewater leads to a serious damage on the environment owing to the high content of organic matters, suspended solids, toxic substances, and lignin. Hence, exploring new treatment technologies is the passion of environmental engineers to minimize the effluent impact on the environment and cleaner production aspects. This research focused on the performance of full-scale coagulation-fluctuation/DAF system for pre-treatment of high strength wastepaper-recycling wastewater and its effect on biodegradability improvement. To optimize unit performance, optimum coagulant and flocculant doses were firstly determined by jar test without prior change and adjustment of pH in lab-scale experiments. The optimum dosages were obtained by 1500mgL-1 polyaluminum chloride (PACl) as coagulant coupled with 40mgL-1 cationic polyacrylamide (C-PAM) as flocculant. Percentage removals of 39 ± 10, 6.8 ± 3.6, 31.0 ± 6.7, 24.0 ± 3.8, and 33.0 ± 20.0 were achieved for COD, sCOD, BOD5, sBOD5, and color, respectively. The average BOD5 to COD ratio after pre-treatment increased from 0.44 to 0.5, whereas the ratio of sBOD5/sCOD dropped from 0.65 to 0.53. A superior effectiveness in reduction of TSS (98.1%) and VSS (98.4%) was also achieved. The results show that the application process is able to prevent malfunction operation in the following bioreactors which is obtainable through bio-treatability enhancement of pre-treated wastewater and reducing the risks of clogging and sludge washout. Attached growth processes are suggested to be applied in the further anaerobic/aerobic processes because of high proportion of soluble fraction of COD in the effluent to avoid poor floc formation and dispersed growth problems.

Spatial and seasonal variation in physicochemical parameters and heavy metals in Awash River, Ethiopia

Awash River, one of the major rivers in Ethiopia which originate from the central highland area, crosses different extended agricultural farms as well as various industries which receives large effluents from different sources. Nineteen physicochemical parameters, as well as heavy metals (Fe, Zn, Cu, Pb, Cr, Cd and Ni), were quantified using atomic absorption spectroscopy in eight different sampling stations of Awash River. There was a significant spatial variation (p < 0.05) in average NO3-N, NH4-N, TN, BOD and COD values in Awash River. There is a strong and positive correlation between (pH and EC, r = 0.805), (WT and BOD, r = 0.774), (NO3-N and NO2-N, r = 0.901), (NO3-N and TN, r = 0.906), (NO3-N and TP, 0.830), (NH4-N and TN, r = 0.876), (NH4-N and COD, r = 0.848), (TN and TP, r = 0.819), (TN and COD, r = 0.941) during dry season and also between (WT and BOD, r = 0.704), (turbidity and NO3-N, r = 0.749), (turbidity and NO2-N, r = 0.722), (NO3-N and NO2-N, r = 0.921), (TP and COD, r = 0.789) during wet season. The results showed that the mean concentrations of metals ranked (high to low) Fe > Cr > Cu > Zn > Pb > Cd > Ni during dry season, whereas the concentration of heavy metals during wet season was in the following order of decreasing magnitude Fe > Cu > Zn > Pb > Cr > Cd > Ni. Buffer zones should be protected in order to control soil and agricultural nutrients from entering to Awash River. Moreover, industries at the upper stream area should be properly and adequately treat the wastewater before discharging to the Modjo as well as Awash River.

Assessment and remediation of pollutants in Ghana's Kete-Krachi District Hospital effluents using granular and smooth activated carbon

The need for simple, cheaper and high performance hospital effluent treatment system in Kete-Krachi District which is adjacent to the Lake Volta has necessitated this study. This study focuses on assessing, and treating Kete-Krachi District Hospital effluent using packed granular (GAC) and smooth activated carbon (SAC). The use of activated carbon is due to its less expensive method of operation, the ease to prepare from local raw materials, high availability, and effectiveness for treating hospital effluent. The dissolved oxygen (DO), chemical oxygen demand (COD), biochemical oxygen demand (BOD), nutrient compounds (P-PO4, N-NO3), turbidity, pH, conductivity and total coliform parameters were investigated and later treated with the activated carbon. The average conductivity and P-PO4 removals were <50%. The average BOD5, COD, coliform, N-NO3, and turbidity removals for all the SAC treatments were 58.36%, 62.26%, 84.39%, 83.86%, and 50.74%, respectively. The DO also improved 3.8 times on the average. The pH of the raw and treated samples was within the limit 6.5–9. The results of this study suggest that the SAC is predominantly effective for reducing the pollutants concentrations of the hospital effluent which can result in oxygen depletion, eutrophication, algal bloom and ecosystem disturbance in the Lake Volta. It will also decrease the susceptibility of the Kete-Krachi residents to waterborne diseases as the effluents seep into the Lake.

Analyzing the Relationship between Financial Variables and Market Risk in the Tourism Industry

The purpose of this study is to analyze the performance of hotel industries in France during five years. The chosen companies are InterContinental Paris Le Grand Hotel, Pierre & Vacances-Center Parcs Group, Mandarin Oriental Hotel Group and AccorHotels. The analysis is applied on the sample of four company in France over the period between 2012 and 2016. This study is utilizing internal factors such as profitability ratio, liquidity ratio, leverage ratio, average collection period, index score, and BOD remuneration besides considering external factors which include GDP, inflation rate, unemployment rate and exchange rate to see the overall performance and their relationship for four chosen companies among five years. The study found that the companies need to concern more about liquidity risk and operational risk in order to enhance its performance.