This study assessed the effectiveness of integrating electrocoagulation, magnetic fields, and ozonation technologies to remove chemical oxygen demand (COD) and total suspended solids (TSS) from tannery wastewater. Furthermore, the effects of their key operating factors were determined. To achieve this goal, an electrocoagulation reactor coupled with a magnetic-field generator was used and the response surface methodology was applied through a Box-Behnken experimental design. Here, current intensity (I), treatment time (T), and ozone concentration (O3) are considered the influencing factors. Likewise, the removal percentages of COD and TSS serve as response indicators. The results indicate that T, I, and O3 are significant for the removal of COD and TSS at a confidence level of p-value < 0.05. For COD, the optimal operating conditions are I = 6.8 A, T = 30 min, and O3 = 10 mg/l; and for TSS, the optimal conditions are I = 5.72 A, T = 28 min, and O3 = 7.8 mg/l. These conditions yield removal efficiencies of 41.8% for COD and 97.9% for TSS. The findings suggest that integrating these technologies is a viable alternative for mitigating the pollution issues caused by the tannery industry.
This study aimed to determine the performance of modified slow sand filter (SSF) media with blood clam shells (Anadara granosa) and activated carbon to remove turbidity, TSS, TDS, and FOG on the food court wastewater. The concentration of water pollutant parameters processed by SSF was determined based on Indonesia water quality standards, as well as knowing the optimum operational parameters of intermittent slow sand filter with Response Surface Methodology (RSM). The research data was processed using the Optimal type (custom) design which consisted of independent factors including the type of filter media, the addition of bacteria to the grease trap pre-treatment unit, and running time, as well as the research response in the form of the effectiveness of removing turbidity, TSS, TDS, and FOG. The reactor was operated intermittently (48 hours) for a maximum of 22 days and the concentration of pollutant parameters was calculated using the Standard Methods. The results of the Analysis of Variance (ANOVA, p<0.05) in the 2FI model of the study showed that there was a significant effect of all independent factors on the effectiveness of removing all water pollutant parameters. The most optimal operational parameters were achieved with the type of activated carbon media, the addition of Bacillus sp. in the grease trap pre-treatment unit in the amount of as much as 1%, and the detention time of 4 days, with the effectiveness of removing turbidity reaching 39.53%; TSS 45.25%; TDS 19.30%; FOG 61.35%.
Treatment of Municipal wastewater by Electrocoagulation (EC) process using punched aluminium and zinc electrodes was studied in a batch EC cell reactor. Response surface methodology (RSM) based on Central Composite Design (CCD) was utilized to optimize the operating parameters for the removal of % Total Suspended Solids (TSS) and % Chemical Oxygen Demand (COD) from Municipal Sewage. Effect of operating parameters such as Electrode Distance (x1), Electrolysis Time (x2) and Voltage (x3) has been optimized for the removal of TSS and COD. The prediction of removal percentage of TSS and COD in various Operational circumstances is done by using Quadratic model. The significance of each operating parameter was computed by Analysis of variance (ANOVA). To achieve the maximum removal of % TSS and % COD, the optimum conditions were Electrode distance(x1)-3 cm, Electrolysis Time (x2)-70.299 minute and Voltage (x3)-6.5V. It was observed that the performance of electrocoagulation process increased up to 61.45% for COD removal, and 73.73% for TSS removal using punched electrode compared to plane electrodes.
The hospitals close to the residences can make problems for the environment as a consequence of sewage drained into the water stream. Sequencing batch biofilm reactor (SBBR) offers advantages for treating sewage; such as simple operation, flexible process, and cost-effective. The laboratory bench-scale experiments were carried out treating hospital wastewater (HWW) of one of Basrah hospital city by a fabricated SBBR reactor of 26 l working volume. The hospital wastewater has the following characteristics (average values): pH 7.3, BOD equal to 280 mg·l–1, COD equal to 550 mg·l–1, total phosphorus (TP) equal to 6.4 mg·l–1, ammonia (NH3-N) equal to 44 mg·l–1 and total suspended solid (TSS) equal to 272 mg·l–1. This research aims to estimate the performance of the SBBR system for treating hospital wastewater to enhance different effluent parameters such as COD, total nitrogen (TN), ammonia, and total phosphorous (TP) with various dissolved oxygen (DO) with range of 2.15–6.55 mg·l–1, the best DO values give these removal efficiencies for COD equal to 84.55%, NH3-N equal to 65.91% and TN between 78 and 18% for DO equal to 3.67 mg·l–1, while TP removal efficiency was 79.70% for DO equal to 6.55 mg·l–1. By comparison of the SBBR effluent with international standards for effluent sewage, it noticed COD concentration 85 mg·l–1, TN 12 mg·l–1 and TP 1.3 mg·l–1 met all standards (European, WHO, and China), while NH3-N 15 mg·l–1 was outside WHO and European standards, while satisfies only Chinese standard.
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The present study investigated the phytoplankton assemblage and diversity with physicochemical parameters of Diu coastal waters in different seasons during 2018–19. During the study period, 61 phytoplankton species comprising diatoms (50 sp.), dinoflagellates (8 sp.), and cyanophyceae (3 sp.) were recorded. Diatom was found to be a major community and contributed 79 to 99% of total phytoplankton abundance. Reduction in dinoflagellate and dominance of pennate-diatoms were observed during the monsoon. Chlorophyll-a concentration also showed a similar trend and decreased during the monsoon. However, the phytoplankton abundance was low particularly during the monsoon which might be due to the elevated total suspended solids (TSS) load. Canonical correspondence analysis revealed that diatoms were able to survive in high TSS with the support of high nutrients; while dinoflagellates were limited due to those conditions. Overall, the reduction in phytoplankton abundance, diversity, and biomass was recorded due to the elevated TSS input along the coastal waters of Diu.
In this study, the execution and assessment of the ANN approach towards the declaration of the pollution was used. The ANN-based models for prediction of Chemical and Biological Oxygen demands, (COD & BOD5) and Total Suspended Solids (TSS) concentrations in the effluent were formed using a three-layered feed forward back propagation algorithm ANN towards assessing the performance of a wastewater treatment plant (WWTP). Two types of configurations were used, MISO and MIMO. The study showed the superiority of MIMO according to the results of R and MSE, which were used as evaluation functions for the predicted models. The results also showed that the model built to predict the values of BOD5 concentrations demonstrate the best performance among the rest of the models by achieving the value of correlation coefficient up to 0.99. Among the input combinations tested in the study, the models the inputs of which did not contain BOD5 had the best performance, which demonstrates that the BOD5 has the largest influence on the values of R in the COD prediction models as well as other predicted models than TSS and other parameters; consequently, the performance of the WWTP was greatly affected. This study demonstrated the value of using artificial networks to represent the complex and non-linear relationship between raw influent and treated effluent water quality measurements.
This study aims to optimize the removal of total suspended solids (TSS) in pump water from fish flour factories through electrocoagulation technology and to determine the effects of the main operation parameters. Pump water has high conductivity (40.1 mS), due to the presence of dissolved salts and contains high concentration of organic substances (12,360 mg/L of TSS and 520 mg/L of fats). In this study, pump water was treated in an electrocoagulation reactor with aluminum electrodes using Response Surface Methodology with a 3k factorial design based on two factors, current intensity (I) of 8-13 A and treatment time (t) of 20-40 minutes. The percentage of TSS removed from the water was used as the response variable. The results revealed that I and t significantly (p < 0.05) influenced the process. In accordance, the optimal operational parameters for TSS removal were I = 13 A and t = 30 minutes. Using these conditions, TSS removal efficiency of 99.9% was achieved. The sewage sludge generated with these optimal process conditions indicated 19.3% of ash content, 6.2% of salt, 1.7% of aluminum, 0.3% of iron, 0.4% of potassium, 256 ppm of zinc, and 2.1% of phosphorus. Hence, the results of this study affirm that electrocoagulation can be considered as a solution for marine pollution caused by fishing industries.
The purpose of the study is to evaluate the efficiency of removing organic pollutants from wastewater in a household wastewater treatment plant with a hybrid reactor. The efficiency of the plant was analyzed in terms of decreasing BOD5, COD and the content of total suspended solids in differentiated technological conditions. The variable parameter was the length of the reactor aeration phase and the dwell phase. Six different aeration variants were analyzed. The efficiency of a wastewater treatment plant with a hybrid reactor in terms of reducing BOD5 oscillated from 81 to 90%, COD – 64–84%, whereas total suspended solids – 66–89% which, as a rule, was not sufficient to achieve standard levels. The best results were achieved for the following variants: 2h aeration – 2h dwell and 1h aeration – 0.5h dwell. Lower efficiency of the plant could have been attributed to operational problems, mainly failures of the plant control system and uneven conditions such as air temperature, volume and composition of wastewater received in the plant.
The paper presents preliminary results of investigations on a relationship between turbidity and other quality parameters in the SBR plant effluent. The laboratory tests demonstrated a high correlation between an effluent turbidity and a total suspended solids (TSS) concentration as well as between TSS and COD. Such a relationship would help to continuously monitor and control quality of a wastewater discharge using turbidity measurement.
PL
W artykule przedstawiono wstępne wyniki badań zależności pomiędzy mętnością a innymi wskaźnikami zanieczyszczeń w ściekach oczyszczonych odpływających z oczyszczalni z reaktorami osadu czynnego o działaniu cyklicznym typu SBR. Wykonane badania potwierdzają wysoką korelację zarówno pomiędzy wartością mętności a stężeniem zawiesiny jak i pomiędzy wartością mętności a ChZT w ściekach oczyszczonych co może pozwolić na ciągłą kontrolę i sterowanie jakością ścieków odpływających do odbiornika przy zastosowaniu pomiaru mętności.
The coastal zone and estuaries of Quang Ninh and Hai Phong have great potential not only for economic development but also for protection and conservation of biodiversity and ecosystem. Nowadays, due to industrial, agricultural and anthropogenic activities signs of water pollution in the region have been found. The level of surface water pollution can be determined by traditional methods through observatory stations. However, a traditional approach to determine water contamination is discontinuous, and thereby makes pollution assessment of the entire estuary very difficult. Nowadays, remote sensing technology has been developed and widely applied in many fields, for instance, in monitoring water environments. Remote sensing data combined with information from in-situ observations allow for extraction of polluted components in water and accurate measurements of pollution level in the large regions ensuring objectivity. According to results obtained from Spot-5 imagery of Quang Ninh and Hai Phong, the extracted pollution components, like BOD, COD and TSS can be determined with the root mean square error, the absolute mean error and the absolute mean percentage error (%): ±4.37 (mg/l) 3.86 (mg/l), 27%; ±55.32 (mg/l), 48.30 (mg/l), 14%; and ±32.90 (mg/l), 23.38 (mg/l), 28%; respectively. Obtained outcomes guarantee objectivity in assessing water contaminant levels in the investigated regions and show the advantages of remote sensing applications in Resource and Environmental Monitoring in relation to Water – Air – Land.
PL
Strefa przybrzeżna i ujścia rzek w Quang Ninh – Hai Phong ma potencjał do rozwoju gospodarczego i ochrony różnorodności biologicznej i ekosystemu. Ostatnio stwierdzono tam wiele oznak zanieczyszczenia wody. Poziom zanieczyszczenia wód powierzchniowych może być określany na stacjach obserwacyjnych metodami tradycyjnymi, jednak znacznie szybsze i dokładniejsze jest wykorzystanie metod teledetekcyjnych. Analiza obrazów Spot-5 w Quang Ninh – Hai Phong umożliwiła stwierdzenie obecności różnych zanieczyszczeń, w tym BOD, COD i TSS ze średnim błędem kwadratowym, średnim błędem absolutnym i średnim błędem względnym odpowiednio: ± 4.37 (mg/l), 3.86 (mg/l), 27%; ± 55.32 (mg/l), 48.30 (mg/l), 14%; ± 32.90 (mg/l), 23.38 (mg/l), 28%. Otrzymane wyniki gwarantują obiektywizm przy ocenie poziomu zanieczyszczeń w badanych regionach i pokazują korzyści zastosowań teledetekcji w monitoringu zasobów i środowiska w odniesieniu do wody – powietrza – terenu.
W pracy zamieszczone zostały informacje dotyczące technologii sekwencyjnych reaktorów porcjowych SBR wraz z opisem procesów zachodzących w komorach reaktorów tego typu oraz charakterystyką faz cyklu ich pracy. Opracowanie zawiera opis harmonogramu pracy reaktora laboratoryjnego w poszczególnych fazach cyklu, a także wyniki badań wartości wybranych wskaźników zanieczyszczeń: chemicznego zapotrzebowania na tlen (ChZT), zawiesiny ogólnej oraz ogólnego węgla organicznego (OWO), które były analizowane podczas trwania eksperymentu. Niniejsze opracowanie porusza również problem wpływu wielkości ładunku wprowadzanego do komory reaktora SBR (każdego z analizowanych wskaźników) na sprawność procesu oczyszczania ścieków. Z prowadzonych badań wynika, iż stopień oczyszczenia ścieków w reaktorze typu SBR jest na zadowalającym poziomie, o czym świadczą uzyskane wartości stężeń i ładunków zanieczyszczeń w odpływie z komory. Średnie wartości sprawności usuwania zanieczyszczeń kształtowały się na następujących poziomach: ChZT - 94%, OWO 95%, podobnie zawiesina ogólna - 95%.
EN
In the subsequent section of the proposed paper, the technology of sequencing batch reactors (SBR) is discussed, including based processes which take places in SBR reactor and characteristics of the SBR operation cycle. This elaboration contains also the result, of sewage quality measurements such as: chemical oxygen demand (COD), the total suspended solid (TSS) and total organic carbon (TOC) which were analyzed during the experiment. Elaboration also addresses the issues of load variation in influent to chamber of SBR reactor on purification efficiency and contains calculations of activated sludge load and the relation between it and purification efficiency.
Przedstawiono wyniki badań prowadzonych z wykorzystaniem reaktora typu SBR w skali laboratoryjnej, który pracował w cyklu 12-godzinnym. Eksperyment prowadzony był w stałych warunkach temperaturowych, dzięki umieszczeniu komory reaktora w łaźni stabilizowanej termicznie - przy stałej temperaturze 20°C. Artykuł przedstawia wyniki badań uzyskanych podczas próbnego rozruchu reaktora typu SBR (o całkowitej objętości 10 dm3) wraz z jego danymi technologicznymi. Wyniki zestawiono także z założeniami projektowymi oraz odniesiono do regulacji prawnych dotyczących efektów oczyszczania ścieków komunalnych. Ponadto niniejsze opracowanie porusza problem wpływu obciążenia suchej masy osadu ładunkiem zanieczyszczeń na sprawność procesu oczyszczania ścieków i jednocześnie przedstawia zauważone korelacje występujące pomiędzy skutecznością redukcji poziomu poszczególnych wskaźników zanieczyszczeń (ChZT, zawiesina ogólna, fosfor ogólny, azot ogólny, ogólny węgiel organiczny).
EN
The paper presents the results of analyzes carried out on the laboratory scale SBR reactor, which worked at a 12 hour schedule. The experiment was conducted at the constant thermal conditions by placing the reactor chamber in a stabilized bath temperature - at a const temperature of 20°C. Proposed article presents the results of test run of the reactor SBR on a laboratory scale (total volume of 10 dm3) with its technological data. The results obtained relative to the project assumptions and legal regulations concerning the quality of wastewater treatment. Study raises also the problem of the impact of pollutants load onto volatile solids (F/M food to mass ratio) on the quality of wastewater treatment. Furthermore paper shows the observed correlations which exist between the removal efficiency of various pollutant indicators (COD, TSS, total phosphorus, total nitrogen, TOC).
In the paper we present a method for synthesis of a set of connection networks, which fulfill the designer’s assumption. In order to do that, the designed network is presented as a system of Diophantine constraints in a special form. A method to resolve those systems is proposed, which is characterized by lower computational complexity, especially in the case of rare topologies design.
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Techniques to predict temporal variations in concentrations and loads of suspended solids from highway runoff are required to estimate impacts on receiving water ecology and to inform the design of interception/treatment devices. A recent UK study included the collection of rainfall, highway runoff rates and sediment load and quality data from six different sites where motorway runoff drained directly into a receiving watercourse. This data set is used to critically evaluate a previously-published model (Kim et al. 2005) aimed at predicting temporal variations in runoff quality. The comparisons, based on discrete samples collected during 21 storm events, suggest that a simplification of the model, requiring just two parameters, provides a robust estimate of temporal variations in total suspended solids (TSS). Generic parameter values are provided, and the model’s application is illustrated. The model captures first flush effects well, but the identified generic parameters fail to fullypredict the variation in absolute TSS values that are observed in practice.
European plums ‘Bluefre’, ‘Valor’, ‘Valjevka’ and ‘Elena’ cvs. were harvested and graded according to colour and firmness, and on this basis divided into three maturity fractions. The fruits were analysed for mass loss, flesh firmness, total soluble solids (TSS), skin ground colour as well as incidence of fungal diseases and physiological disorders after 4 weeks of cold storage at 1 oC and 2 days of ripening at 20 oC. Significant differences were found in fruit weight loss, skin colour, firmness and TSS among maturity fraction during and after storage. A decrease in firmness, fruit mass, and skin colour as well as an increase in TSS were observed, however all changes depended on the maturity stage during harvest. Less mature fruits withstood better cold storage than more mature. All fruits showed flesh browning symptoms after 4 weeks of storage and the least browning symptoms were found for ‘Valor’, regardless of the fruit maturity during harvest. The most browning symptoms were observed for ‘Valjevka’, which indicates the low suitability of this cultivar for 4-week storage. The best storability was observed for ‘Valor’ due to the best after-storage quality. Both firmness and skin colour can be applied to the assessment of the optimum harvest date of fruits intended for storage.
PL
Odmiany śliwy 'Bluefre', 'Valor', 'Valjevka' i 'Elena' po zbiorze zostały rozsortowane w zależności od wybarwienia i jędrności na trzy grupy różniące się stadium dojrzałości. Po 4 tygodniach przechowywania w chłodni zwykłej w temperaturze 1 oC i 2 dniach dojrzewania w temperaturze 20 oC analizowano stratę masy owoców, jędrność, zawartość ekstraktu, barwę skórki oraz występowanie chorób grzybowych i fizjologicznych. Stopień dojrzałości owoców w czasie zbioru wpływał na utratę masy na skutek transpiracji, na zabarwienie owoców, jędrność i zawartość ekstraktu po 2 i 4 tygodniach przechowywania. Jędrność i masa owoców malała, a zwiększała się zawartość ekstraktu, jednak tempo i stopień tych zmian były ściśle uzależnione od stadium dojrzałości w czasie zbioru. Mniej dojrzałe owce wykazywały mniejsze straty spowodowane chorobami grzybowymi, jednak u wszystkich odmian po 4 tygodniach stwierdzono fizjologiczne przebarwienia miąższu. Najmniejsze zbrunatnienie stwierdzono u owoców odmiany 'Valor', a ponadto nie było ono uzależnione od początkowej dojrzałości. Największe zbrunatnienie miąższu stwierdzono po przechowywaniu owoców odmiany 'Valjevka', natomiast największe straty powodowane chorobami grzybowymi u owoców odmiany 'Elena', co pozwala uznać je za mało przydatne do 4-tygodniowego przechowywania w chłodni.