scholarly journals Study on the preparation of granular alum sludge adsorbent for phosphorus removal

2019 ◽  
Vol 79 (12) ◽  
pp. 2378-2386 ◽  
Author(s):  
H. F. Wu ◽  
J. P. Wang ◽  
E. G. Duan ◽  
Y. F. Feng ◽  
Z. Y. Wan ◽  
...  
Keyword(s):  
Removal Rate ◽  
Low Cost ◽  
Average Pore Size ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Water Treatment Plant ◽  
Raw Material ◽  
Phosphorus Concentration ◽  
Average Pore ◽  
Alum Sludge

Abstract Alum sludge is the sludge discharged from a sedimentation tank in a drinking water treatment plant when polymerized with poly-aluminum chloride (PAC). In this paper, granular alum sludge adsorbent (GASA) was manufactured using powdery alum sludge (PAS) as the raw material and methods such as gluing and pore-forming. The effects of different binders, pore-forming agents, roasting temperatures, and roasting times on the formation of GASA and its dephosphorization performance were investigated. Results showed that the optimum binder was AlCl3 at a mass ratio of 8%, and the best pore-forming agent was starch at a 4% dosage ratio. Meanwhile, the optimum roasting temperature and time were 500 °C and 2 hours, respectively. The specific surface area of GASA was 23.124 m2/g. Scanning electron microscopy suggested that GASA's surface became rough, particles became tight, and average pore size increased, with additional pore channels. P adsorption by GASA reached 0.90 mg/g. The effluent phosphorus concentration of actual tail water decreased to 0.49 mg/L and the removal rate reached 73.5% when the GASA dosage was 20 g/L. The findings of this study are important for the further development of a low-cost adsorbent material for P removal in the future.

Characterization of Raw and Thermally Treated Alum Sludge

2016 ◽  
Vol 701 ◽  
pp. 138-142 ◽  
Author(s):  
Mohamat Yusuff Soleha ◽  
Keat Khim Ong ◽  
Wan Yunus Wan Md Zin ◽  
Ahmad Mansor ◽  
Fitrianto Anwar ◽  
...  
Keyword(s):  
Water Treatment ◽  
Heating Temperature ◽  
Low Cost ◽  
Waste Product ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Water Treatment Plant ◽  
Alum Sludge ◽  
Thermally Treated

Use of alum as a coagulant in drinking water treatment process generates an alum sludge as a waste product. Since the amount of this sludge is huge, it is crucial for a water work management to properly handle and dispose of this sludge. Reuse of this alum sludge as a solid adsorbent is one of the proposed applications for this material but modification and characterization are needed to alter and identify its properties so that optimum benefits are obtained. This paper reports characterization of raw and thermally treated alum sludge. The raw alum sludge was collected from a local water treatment plant and heated at 300 °C and 800 °C for 7 hours using a furnace before characterization using scanning electron microscopy energy (SEM), thermogravimetric (TGA), X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET). The results showed that surface morphology, thermal properties, microstructure, surface area and porosity of the sludge were affected by heating temperature whereby increase the heating temperature resulted in improved thermal stability of the sludge. The results also revealed that both raw and thermally treated alum sludge were mesoporous materials and mainly compose of quartz and kaolinite. It can be said that the sludge could be a good candidate as low cost adsorbent.

scholarly journals Nitrogen-metabolising Microorganism Analysis in Rapid Sand Filters From Drinking Water Treatment Plant by Culturing and Metagenomics

2021 ◽  
Author(s):  
Qihui Gu ◽  
Jun Ma ◽  
Jumei Zhang ◽  
Weipeng Guo ◽  
Huiqing Wu ◽  
...  
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Removal Rate ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Water Treatment Plant ◽  
Amplicon Sequencing ◽  
Metabolic Model ◽  
Rrna Gene ◽  
N Removal

Abstract Sand filter (SFs) are common treatment processes for nitrogen pollutants removal in drinking water treatment plants (DWTPs). However, the mechanisms on the nitrogen-cycling role of SFs are still unclear. In this study, 16S rRNA gene amplicon sequencing was used to characterise the diversity and composition of the bacterial community in SFs from DWTPs. Additionally, metagenomics approach was used to determine the functional microorganisms involved in nitrogen cycle in SFs. Our results showed that Proteobacteria, Acidobacteria, Nitrospirae, and Chloroflexi dominated in SFs. Subsequently, 85 high-quality metagenome-assembled genomes (MAGs) were retrieved from metagenome datasets of selected SFs involving nitrification, assimilatory nitrogen reduction, and denitrification processes. Read mapping to reference genomes of Nitrospira and the phylogenetic tree of the ammonia monooxygenase subunit A gene, amoA, suggested that Nitrospira is abundantly found in SFs. Furthermore, according to their genetic content, a nitrogen metabolic model in SFs was proposed using representative MAGs and pure culture isolates. Quantitative real-time polymerase chain reaction (PCR) showed that ammonia-oxidising bacteria (AOB) and archaea (AOA), and complete ammonia oxidisers (comammox) were ubiquitous in the SFs, with the abundance of comammox being higher than that of AOA and AOB. Moreover, we identified a bacterial strain with a high NO3-N removal rate as Pseudomonas sp., which could be applied in the bioremediation of micro-polluted drinking water sources. Our study provides insights into functional nitrogen-metabolising microbes in SFs of DWTPs.

scholarly journals CHLORIDE REMOVAL FROM LANDFILL LEACHATE BY THE ULTRA-HIGH LIME WITH ALUMINUM PROCESS

2017 ◽  
pp. 3-8 ◽  
Author(s):  
Gang Chen ◽  
Peter Grasel ◽  
Gary Millington ◽  
John Hallas ◽  
Hafiz Ahmad ◽  
...  
Keyword(s):  
Landfill Leachate ◽  
Organic Contaminants ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Water Treatment Plant ◽  
Waste To Energy ◽  
Aluminum Concentration ◽  
Energy Applications ◽  
Alum Sludge ◽  
Chloride Removal

Besides organic contaminants, nutrients and heavy metals, high concentrations of chloride have also been observed in landfills accepting ash deposition from waste-to-energy applications, which is difficult be removed in wastewater treatment processes. Chloride may percolate and cause surface salt formation and soil alkalinity increase, thereby resulting in loss of soil. In plants, chloride tends to accumulate in the tissues, especially the leaves. Conventional removal techniques are not feasible from the cost perspective. In this research, the ultra-high lime with aluminum process was evaluated for chloride removal from landfill leachate by precipitation as calcium chloroaluminate (Ca4Al2Cl2(OH)12) in the presence of calcium and aluminum at high pH. Chloride removal was found to be a function of both aluminum concentration and pH. Chloride removal increased with the increase of alum addition until 20 mg/L, after which the chloride removal became moderate. With the increase of pH, obviously more chloride was removed. At pH of 10, the removal reached 90%. To save the chemical costs, alum sludge from a drinking water treatment plant was tested for the removal of chloride from the landfill leachate. The results showed that the supernatant of the alum sludge was more efficient than that of alum sludge suspension in chloride removal. The usage of alum sludge can dramatically save the chemical costs.

Analysis of Plant and Soil from Alum Sludge Farm of Drinking Water Treatment Plant

2012 ◽  
Vol 6 (5) ◽  
pp. 184-197
Author(s):  
Ooi Chong Hoe ◽  
Siti Rozaimah Sheikh Abdullah ◽  
Noorhisham Tan Kofli ◽  
Mushrifah Idris
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Water Treatment Plant ◽  
Drinking Water Treatment Plant ◽  
Alum Sludge

scholarly journals Application of Enhanced BAC Process for Improving Drinking Water Treatment Efficiency

2020 ◽  
Vol 42 (6) ◽  
pp. 298-307
Author(s):  
Heejong Son ◽  
Eun-Young Jung ◽  
Hoon-Sik Yoom ◽  
Sang-Goo Kim ◽  
Sung Kyu Maeng
Keyword(s):  
Hydrogen Peroxide ◽  
Activated Carbon ◽  
Water Treatment ◽  
Large Scale ◽  
Removal Rate ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Water Treatment Plant ◽  
Cell Counts ◽  
The Nakdong River

Objectives:In this study, we compared the properties of the attached biofilm with the ability to remove biodegradable dissolved organic carbon (BDOC) in the conventional BAC (biologically activated carbon) process and the enhanced BAC process with phosphorus and hydrogen peroxide added. The enhanced BAC process was designed to increase the operational efficiency of the old O<sub>3</sub>/BAC process by evaluating the applicability of large-scale water treatment facilities located downstream of the Nakdong River.Methods:The granular activated carbon which was used for 2 years in the O<sub>3</sub>/BAC process in the water treatment plant located downstream of the Nakdong River was used in this experiment. During the experiment period, the ozone dosage was fixed at 1 mg･O<sub>3</sub>/mg･DOC. Four acrylic columns with an inner diameter of 20 cm and a height of 250 cm were prepared. Empty bed contact time (EBCT) was fixed at 20 minutes and backwash was performed once a week. The four BAC columns are conventional BAC (control-BAC), enhanced BAC with hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>+BAC), enhanced BAC with phosphorus (PO<sub>4</sub>-P+BAC), and enhanced BAC with phosphorus and hydrogen peroxide together (PO<sub>4</sub>-P+H<sub>2</sub>O<sub>2</sub>+BAC). In the case of enhanced BAC with PO<sub>4</sub>-P added, PO<sub>4</sub>-P was added with a concentration of 0.010 mg/L in the influent, and in BAC with H<sub>2</sub>O<sub>2</sub>, H<sub>2</sub>O<sub>2</sub> was added with a concentration of 1 mg/L to the influent.Results and Discussion:As a result of evaluating the recovery ability of the damaged biofilm, there was no difference in the biomass recovery rate in the H<sub>2</sub>O<sub>2</sub>+BAC compared to the control-BAC, but the biomass was rapidly recovered in the PO<sub>4</sub>-P+BAC. Considered the biomass and activity of the attached biofilm after the ability to remove organic substances reached a steady state, the biomass and activity in the entire filter layer of the PO<sub>4</sub>-P+BAC increased by 20 to 86% and 7 to 14%, respectively, compared to the control-BAC. In the H<sub>2</sub>O<sub>2</sub>+BAC, only the activity increased by 3~11% and In the PO<sub>4</sub>-P+H<sub>2</sub>O<sub>2</sub>+BAC, biomass and activity were high, about 27 to 87% and 8 to 20%, respectively. In the H<sub>2</sub>O<sub>2</sub>+BAC, the BDOC removal rate was higher than the control-BAC by 20%, and in the PO<sub>4</sub>-P+BAC, the BDOC removal rate increased by more than 100%. Detached total cell counts (TCC) in the control-BAC effluent was 41.7×10<sup>6</sup> cells/mL on average, and in the H<sub>2</sub>O<sub>2</sub>+BAC, TCC was reduced by 49% compared to control-BAC and decreased by 67% and 85% in the PO<sub>4</sub>-P+BAC and the PO<sub>4</sub>-P+H<sub>2</sub>O<sub>2</sub>+BAC effluent. It means the biofilm of the enhanced BAC process was evaluated more stably than control-BAC.Conclusions:The biomass and the activity of the attached biofilm in the BAC process, are one of the important factors that determine the ability to remove contaminants. The enhanced BAC process combined PO<sub>4</sub>-P with H<sub>2</sub>O<sub>2</sub> was very effective in enhancing the biomass and the activity of the attached biofilm. The PO<sub>4</sub>-P added enhanced BAC was more effective in terms of biomass, BDOC removal rate, and biofilm stability than the H<sub>2</sub>O<sub>2</sub> added enhanced BAC. The enhanced BAC combined PO<sub>4</sub>-P with H<sub>2</sub>O<sub>2</sub> showed a slight increase additional efficiency compared to the PO<sub>4</sub>-P added BAC.

scholarly journals PHOSPHATE REMOVAL FROM AQUEOUS SOLUTION BY USING MODIFIED SLUDGE FROM WATER TREATMENT PLANT

2018 ◽  
Vol 56 (2C) ◽  
pp. 43-49
Author(s):  
Dang Thi Thanh Loc
Keyword(s):  
Aqueous Solution ◽  
Water Treatment ◽  
Low Cost ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Water Treatment Plant ◽  
Phosphate Removal ◽  
Maximum Adsorption Capacity ◽  
P Concentration ◽  
P Removal

Heat and humic acid modified sludge (MS) from drinking water treatment plant (DWTP) is used as an adsorbent for removal of phosphate (P) from aqueous solution. The MS was characterized by XRD and SEM observation. The effects of pH, adsorbent dosage, initial P concentration, and exposure time on the P removal were studied. Under identical treatment conditions (MS dosage = 10 g/L, initial P concentration = 10 mg/L, pH 7, 120 rpm, and room temperature), a removal efficiency of 91  % was obtained within 240 min. The Freundlich and Langmuir adsorption models were used for the mathematical description of adsorption equilibrium and it was found that P removal was best described by Langmuir model. The maximum adsorption capacity of the adsorbent based on sludge of Quang Te DWTP was 0.90 mg/g. The adsorption process followed pseudo-second-order kinetics (R2 ≥ 0.98). These findings suggest that MS has potential applications as a low-cost adsorbent for P treatment.

scholarly journals Effects of pre-ozonation and chemical coagulation on the removal of turbidity, color, TOC, and chlorophyll a from drinking water

2019 ◽  
Vol 6 (1) ◽  
pp. 53-61 ◽  
Author(s):  
Bahman Masoomi ◽  
Neamatollah Jaafarzadeh ◽  
Tayebeh Tabatabaie ◽  
Esmaeil Kouhgardi ◽  
Sahand Jorfi
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Chlorophyll A ◽  
Contact Time ◽  
Removal Rate ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Water Treatment Plant ◽  
Pilot Scale ◽  
Alkaline Ph

Background: Ozone can be used as a single technology or in combination with other processes to improve the coagulation- flocculation or biodegradability in order to remove pollutants in natural water treatment. Methods: In this study, the effects of pre-ozonation with coagulant substances on the quality parameters of drinking water were investigated using humic acid, kaolin, clay, and green algae in a pilot scale. This study was conducted under laboratory conditions (at both acidic and alkaline pH in different dosages of ozone and coagulant at ozone contact time with simulated water sample (5-20 minutes) in different scenarios). Results: The highest removal efficiency of parameters in the state of pre-ozonation alone and preozonation with a coagulant was observed at contact time of 20 minutes, ozone dosage of 5 g/h, coagulant dosage of 25 mg/L, at alkaline pH along with a decrease in temperature. So that, the average removal rate of turbidity, total organic carbon (TOC), color, and chlorophyll a in contact time of 20 minutes was 76.9%, 52.8%, 66.6%, and 85%, respectively. However, compared to ozonation under similar conditions, the reduction in turbidity, TOC, color, and chlorophyll a was 36.13%, 24.4%, 32.13%, and 79.6%, respectively. Also, it was revealed that pre-ozonation with coagulant could effectively improve the removal of parameters. Conclusion: However, since pre-ozonation can be effectively used to improve the coagulation efficacy in the drinking water treatment, the pre-ozonation combined with coagulation is proposed as an alternative to conventional coagulation to improve the process of drinking water treatment plant.

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