Feasibility Study on Application of Natural Coagulants

Creating nations are confronting consumable water gracefully issues because of lacking money-related assets. The expense of water treatment is expanding, and the nature of waterway water isn’t steady because of a suspended and colloidal molecule load brought about via land advancement and high tempest overflow during the stormy season. Because of numerous issues made by utilizing engineered coagulants a popularity to locate an elective characteristic coagulant emerges. In this exertion, an endeavor is made to examine the likelihood of normal coagulants like Cassia Alata, Calotropis Procera, Hyacinth bean, Banana leaves, Carcia Papaya, Acacia Mearnsii, Jatropha Curcas, Cactus, and Tamarind seeds on the reduction of turbidity of water. The clump coagulation test was done to decide the ideal coagulant amount required for the evacuation of turbidity of 100 NTU and to recognize the successful coagulant out of the nine chose normal coagulants. From this study, it may be accomplished that banana leaf can be used as an effectual coagulant for low and medium turbid water, whereas for high turbid water cactus can be used as an effective coagulant. Further examinations were completed utilizing the recognized coagulant to streamline the parameters like coagulant measurements, pH, introductory turbid focus, blending time, blending rate, and settling time. The higher percentage removal of turbidity was observed when pH was maintained at 6.5, initial turbid concentration was 500NTU, rapid mixing time given was 1 minute, slow mixing time with 25 minutes, and settling time of 25 minutes.

Four-dimensional chromosome reconstruction elucidates the spatiotemporal reorganization of the mammalian X chromosome

Chromosomes are segmented into domains and compartments, but how these structures are spatially related in three dimensions (3D) is unclear. Here, we developed tools that directly extract 3D information from Hi-C experiments and integrate the data across time. With our “4DHiC” method, we use X chromosome inactivation (XCI) as a model to examine the time evolution of 3D chromosome architecture during large-scale changes in gene expression. Our modeling resulted in several insights. Both A/B and S1/S2 compartments divide the X chromosome into hemisphere-like structures suggestive of a spatial phase-separation. During the XCI, the X chromosome transits through A/B, S1/S2, and megadomain structures by undergoing only partial mixing to assume new structures. Interestingly, when an active X chromosome (Xa) is reorganized into an inactive X chromosome (Xi), original underlying compartment structures are not fully eliminated within the Xi superstructure. Our study affirms slow mixing dynamics in the inner chromosome core and faster dynamics near the surface where escapees reside. Once established, the Xa and Xi resemble glassy polymers where mixing no longer occurs. Finally, Xist RNA molecules initially reside within the A compartment but transition to the interface between the A and B hemispheres and then spread between hemispheres via both surface and core to establish the Xi.

Optimization of the humic acid separation and coagulation with natural starch by RSM for the removal of COD and colour from stabilized leachate

The removal of concentrated colour (around 5039 Pt–Co) and chemical oxygen demand (COD; around 4142 mg L−1) from matured landfill leachate through a novel combination of humic acid extraction and coagulation with natural oil palm trunk starch (OPTS) was investigated in this study. Central composite design from response surface methodology of Design Expert-10 software executed the experimental design to correlate experimental factors with desired responses. Analysis of variance developed the quadratic model for four factors (e.g. coagulant dosage, slow mixing speed and time and centrifugation duration) and two responses (% removal of colour, COD). The model confirmed the highest colour (84.96%) and COD (48.84%) removal with a desirability function of 0.836 at the optimum condition of 1.68 g L−1 coagulant dose, 19.11 rpm slow mixing speed, 16.43 minutes for mixing time and 35.75 minutes for centrifugation duration. Better results of correlation coefficient ( R2 = 0.98 and 0.96) and predicted R2 (0.94 and 0.84) indicates the model significance. Electron microscopic images display the amalgamation of flocs through bridging. Fourier transforms infrared spectra confirmed the existence of selected organic groups in OPTS, which eventually signifies the applied method.

Optimalisasi Penggunaan Kitosan Limbah Kulit Udang Vannamei Sebagai Koagulan dalam Perbaikan Kualitas Air Danau

Danau di Universitas Hasanuddin atau Danau UNHAS telah mengalami pencemaran sehingga tidak dapat dimanfaatkan secara optimal. Kitosan dari limbah kulit udang Vannamei dari Kawasan Industri Makassar (KIMA) dapat digunakan sebagai bahan untuk proses penjernihan air. Penelitian ini bertujuan untuk mengetahui pengaruh konsentrasi kitosan dan kecepatan pengadukan pada proses penjernihan air danau UNHAS. Metode yang digunakan adalah jar test, rapid mixing dan slow mixing dengan varian penambahan konsentrasi kitosan berturut-turut 0.5, 1, 1.5, 2, 2.5 (% berat) pada kecepatan putar pengadukan cepat berturut-turut 100, 300, 500, dan pengadukan lambat 70 rpm. Hasil penelitian menunjukkan bahwa kualitas air danau terbaik dari segi pH dicapai pada penambahan kitosan 0,5%, sedangkan dari segi TDS dan suhu, kualitas air terbaik diperoleh pada penambahan kitosan 2,5%. Kecepatan optimum pengadukan yang memberi kualitas air terbaik dari segi pH dan TDS adalah pada 500 rpm, sedangkan kecepatan optimum yang meberikan kualitas air dengan suhu terbaik diperoleh pada kecepatan 100 rpm. Secara umum, penelitian ini menunjukkan bahwa kitosan kulit udang memiliki potensi untuk digunakan sebagai koagulan untuk proses perbaikan kualitas air danau.

Coagulation Treatment of Wastewater: Kinetics and Natural Coagulant Evaluation

In this study, three coagulants (ferromagnetite (F), alum (A), and eggshells (E)) and their hybrids (FA, FE, and FEA) were investigated as possible cost-effective coagulants for the treatment of industrial wastewater. Scanning electron microscopy (SEM) coupled with energy-dispersive X-ray (EDX) was used to characterize the morphological and elemental compositions of the coagulants. The effects of coagulant dosage (10–60 mg/L) and settling time were investigated for the removal of turbidity, color, and total suspended solids. A jar tester (JTL6) operating at conditions of 150 rpm for 2 min (rapid mixing) and 30 rpm for 15 min (slow mixing) was employed. Results from the characterized supernatant showed about 80% removal of the contaminants. The prospects of F were proven to be the most effective as compared to the binary (FA > FE) and the ternary hybridized (FEA) coagulants. At an optimum dosage and settling time of 20 mg/L and 30 min, respectively, the treatability performance of F was clearly proven to be viable for wastewater treatment.

On the Use of Iron Chloride and Starch for Clarification in Drinking Water Treatment

In drinking water treatment plants, chemical reagents are employed to aggregate and remove suspended particles. However, not all reagents are eco-friendly and exists concerns over environmental, economic, and health issues. This study shows features of the sustainability of commercial coagulants/flocculants and presents experimental research on floc characterization and settling of dispersed solids with a combination of Ferric Chloride (FeCl3 ) and gelatinized starch. Bench studies were conducted using kaolin suspensions and results were validated with raw water collected from a river (Rio dos Sinos, Brazil). Flocculation indexes, floc structure, and residual turbidities were compared with Polyaluminum Chloride (PAC), as a reference. All techniques showed that the combination of FeCl3 and starch formed well-structured, larger, and more settleable flocs than those produced with PAC. Superficial loadings, in a continuous separation tank (2 to 4 m.h-1) were studied with and without lamellae. Best results were obtained with 15 mg.L-1 Fe3+ and 10 mg.L-1 starch, with a velocity gradient, G, of 60 s-1 in the slow mixing and with 60° inclined lamellae spaced 1.3 cm apart. Best conditions were applied to the clarification of the raw water and again, due to the rapid settling of flocs with FeCl3 and starch, better results were obtained compared to PAC. A turbidity reduction of 94% and a residual value of 2.5 NTU with superficial loadings of 3 m.h-1 were obtained. Results were discussed in terms of interfacial and operating parameters and a promising potential for the combination of FeCl3 with starch for solid/liquid separation was envisaged.

Simulation of Wastewater Depolution Processes by Advanced Biological Methods

This paper presents the results from a study which simulates wastewater depollution processes using advanced biological methods. The experimental research was performed in a static biological reactor, equipped with an air compressor and an agitator / mixer. Synthetic wastewater, prepared with the addition of glucose, was fed into the reactor. The wastewater was subjected to alternating cycles of aeration and slow mixing, for consecutive 3 h intervals within the reactor to ensure the necessary conditions for the reduction of nitrogen based organic compounds within the wastewater. In the successive aeration processes, aerobic / nitrifying microorganisms which developed within the reactor, facilitated the decomposition of organic substances into nitrites and then into nitrates. By stopping aeration and starting the slow mixing cycle the anaerobic / denitrifying microorganisms growing in the reactor consume the necessary oxygen from nitrates and release free nitrogen into the atmosphere, thus completing the process of advanced depollution. Therefore, the experimental procedure highlights the existence of two distinct phases in the development of the depollution process. In the first phase, the biological process is initiated using glucose in order to promote the growth of the bacterial flora. In the second phase (the regime phase), the reduction of mineral and organic pollutants from the wastewater is ensured. The activity of microorganisms in the biological reactor can be further supported by the recirculation of activated sludge retained in the secondary decanter. The proposed technology offers a fast, safe and relatively inexpensive method for advanced wastewater depollution. Bioreactors of this type are recommended in wastewater treatment schemes in the hearth of rural localities, agro-zootechnical complexes and tourist units with seasonal activities due to their fluctuations in hourly wastewater flow rates. Similar approaches can also be considered for the elimination of ammonium compounds in groundwater polluted with animal manure.

Treatment of highly turbid water in disaster conditions using coagulation-flocculation process: modeling and optimization

In the present research, the coagulation-flocculation (CF) process was used to eliminate highly turbid water in disaster conditions. To better understand the efficiency of the system, the impact of various numerical factors namely; initial turbidity (10–350 NTU), pH (5–9), coagulant dosage (50–250 mg/L), rapid mixing (120–280 rpm), slow mixing (30–50 rpm), and sedimentation time (10–50 min) were optimized through the central composite design (CCD) under response surface methodology (RSM). Based on analysis of variance (ANOVA), the quadratic model was more suitable for the dataset with R2 = 0.85 for removing turbidity. Moreover, the results of the present study revealed that the highest turbidity removal (99.14%) was observed at pH (9), alum dosage (50 mg/L), initial turbidity (350 NTU), rapid mixing (280 rpm), slow mixing (50 rpm), and sedimentation time (50 min). Furthermore, the residual turbidity at the maximum efficiency of the system was 3 NTU.

Mixed Culture Microalgae Removal for Water Quality Improvement Using Chitosan

The presence of microalgae affects water quality and beneficial uses of surface freshwaters. Chitosan with proven potential for harvesting specific microalgae species from their culture medium for producing biofuels and bioproducts appears promising for efficient removal of mixed microalgae species from surface freshwaters also. The main thrust of the present study was on removal of mixed microalgae species using chitosan as a coagulant to help improve water quality. Important operational parameters were optimized for economical microalgae removal. The microalgae cells, chlorophyll-a, TN and TP removal efficiency were 82.06, 89.90, 69.32 and 44.01%, respectively at an optimum chitosan dose of 10 mg/L, pH 8, slow mixing time 7 min, slow mixing rate 30 rpm and settling time of 15 min. The results have shown that chitosan coagulation efficiently removed the mixed microalgae species from surface freshwater with significant improvement in water quality and recovery of algal biomass for other beneficial applications.

The removal of turbid materials from AMD using bentonite clay, Fe or Al salt, MgCO3 and flocculent with varying agitations

A series of experiments was conducted using 200 mL of acid mine drainage (AMD) collected from Krugersdorp, South Africa, to determine turbid materials removal efficiency of a combination of bentonite clay, Fe or Al salt and MgCO3. The sample was poured into five 500 mL glass beakers using bentonite clay, FeCl3, AlCl3 and MgCO3 dosage respectively. The samples were treated in jar test at rapid and slow mixing, allowed to settle for 1 hour, then the pH, conductivity, total suspended solids (TSS), dissolved oxygen (DO) and oxidation reduction potential (ORP) were measured (exp A). A second and third similar sets of experiments were conducted with a combination of bentonite clay and MgCO3 (flocculent) dosage (exp B), and FeCl3 with slow mixing only (exp C). Experimental results revealed that the pH of treated effluent with bentonite clay does not exhibit significant increasing trend because of insignificant hydrolysis, whereas the pH of samples with FeCl3, AlCl3 and MgCO3 exhibit a slight decreasing trend, showing a low rate of hydrolysis. The DO and ORP of treated effluent does not show a significant changing trend compared to the untreated AMD sample. Residual TSS of the AMD samples treated with a flocculent is lower than the samples treated with bentonite clay, FeCl, AlCl3 and MgCO3. Residual turbidity of the samples with rapid mixing is identical to that of the corresponding samples with slow mixing. TSS removal efficiency of a flocculent is higher compared to other reagents. The results show that synthetic flocculent is an ideal replacement for inorganic coagulants. The scanning electron microscopy (SEM) micrographs exhibit slides with dense-sponge like flocs showing high adsorption capacity.