Polyaluminum Chloride Concentration Research Articles

Purification of graphite from spent carbon cathodes through the reduction of the mechanical entrainment of cryolite using polyaluminium chloride as a flocculant

Spent carbon cathodes (SCCs) generated during electrolytic aluminum production pose significant environmental hazards. To optimize resource utilization, flotation is used as an early process for the clean recovery of valuable graphite from waste cathodes. However, the mechanical entrainment in flotation restricts the further improvement of product purity, resulting in an increase in waste gas and wastewater discharge in the subsequent purification process. In this study, to increase the fixed carbon content of flotation products, flocculant was first applied to the flotation separation of SCCs, and polyaluminum chloride (PAC) was used to flocculate cryolite with high impurity content to reduce mechanical entrainment in the flotation process. Zeta potential measurements, particle size analysis, optical microscopy, and scanning electron microscopy confirmed the agglomeration of cryolite under the action of PAC. Additionally, the DLVO (Derjaguin, Landau, Verwey, and Overbeek) theory was used to estimate the interaction energy to further explain the mechanism underlying cryolite agglomeration. Interaction energy calculation revealed that the attraction energy between particles was dominant at the PAC concentration of 2000 mg/L. Flotation experiments indicated that under a constant pulp pH of 7.8, the absence of sodium silicate, and a stirring speed of 1200 rpm, mechanical entrainment decreased from 91.53 ± 1.53 g/L to 69.80 ± 1.90 g/L, and the carbon grade of the product increased from 83.07 ± 0.28% to 88.94 ± 0.30%. Overall, the proposed purification method provides a new approach for the efficient recovery of graphite in waste cathodes, which is of great significance for the sustainable development of graphite resources.

Sustainable large-scale Fe3O4/carbon for enhanced polystyrene nanoplastics removal through magnetic adsorption coagulation

The omnipresence of nanoplastics in natural water sources raises significant environmental and health concerns due to their challenging removal and potential to transport harmful pollutants. These particles pose threats to terrestrial and aquatic ecosystems, as well as human health, inducing inflammation and oxidative stress. In response, this study focused on an innovative Fe3O4/C nano-adsorbent, derived from discarded printer cartridge toner, for tackling the removal of polystyrene nanoplastics (PS-NPs) through magnetic adsorption coagulation (MAC) with polyaluminum chloride (PACl) as a coagulant. Extensive experimentation achieved a remarkable 99 % removal efficiency at a desirability function value of 0.868 under optimum conditions (pH = 8, adsorbent dosage 2.5 mg, contact time 2 min, PACl concentration 17.5 mg/L, PS-NPs concentration 75 mg/L) with an R2 = 0.9997, a CV% = 0.730 and an Adeq Precision = 122.837. The dominant removal mechanism involved adsorption bridging and electrostatic interaction between PS-NPs and Fe3O4/C in the presence of PACl. Findings covered adsorption kinetics, isotherms, and thermodynamics, adhering to the pseudo-second-order model (R2 = 0.996), Langmuir (R2 = 0.9912) isotherm and negative value of ΔG° (−8.899) as an endothermic adsorption process. The results demonstrated a maximum adsorption capacity of 523 mg/g, showcasing the effectiveness of the approach. Furthermore, the Fe3O4/C material exhibited robust reusability and stability, owing to its magnetite properties. The primary goal was to engineer a magnetic recoverable nano-adsorbent from discarded toner, contributing to cost reduction, streamlined coagulation processes, reduced coagulant consumption, and significantly improved micro/nanoplastics removal.

Penentuan Kebutuhan Poli Aluminium Klorida pada Proses Penjernihan Air di Unit Water Treatment PT. XYZ Kuala Tanjung

A Water Treatment Unit (WTU) is a station that works on the processing and conditioning of raw water to meet the desired water quality. Water purification at PT. XYZ Kuala Tanjung uses raw water sourced from surface water or rivers. The river water used still contains solid substances and organic matter that render the water unsuitable for industrial use. Both suspended and colloidal solid substances can cause turbidity. Turbidity caused by solid substances can be addressed using coagulation techniques. The purpose of this research is to determine the optimal concentration and dosage of coagulant to clarify water in the WTU. The coagulant used is polyaluminum chloride (PAC). The research method is based on experiments using jar tests and stoichiometric calculations. The determination of the optimal coagulant is measured based on turbidity parameters. Experiments are conducted with varying concentrations of PAC ranging from 25-65 ppm, and the smallest turbidity value obtained is 1.21 NTU at a PAC concentration of 65 ppm, with a PAC requirement of 202.6679 kg/day. The higher the PAC concentration, the clearer the resulting water, but the daily requirement for PAC also increases.

Oily wastewater treatment and reuse technology in low permeability oilfield

This paper takes Ordos Huaqing ultra-low permeability oilfield as the research object, analyzes the composition of the produced oily wastewater, and uses the treatment process of multiphase air flotation to shell filtration to quartz sand filtration to multi-effect evaporation to reuse the oily wastewater in the oilfield, analyzes the index changes of the purified oily wastewater. The results show that it has high oil content, salinity, sulfide, SS, sulfide and iron and manganese content. Through experimental combination and analysis of effluent quality, it is concluded that the process of multiphase air flotation→shell filtration→sand filtration→low temperature multi-effect evaporation is better, The average salinity of sewage in Huaqing oilfield used in the experiment is 2757 mg/L. and the dosage of polyaluminum chloride is 230 mg/L, polyacrylamide is 6 mg/L, the dissolved gas pressure of multiphase air flotation machine is 0.5 MPa, the reflux ratio of multiphase air flotation machine is 0.3, the dosage of defoamer is 5 mg/L, and the pH value is set at 5.5. The best treatment process of oilfield sewage and the best concentration of polyaluminum chloride and polyacrylamide are obtained. The research results provide theoretical data support for improving the treatment and reuse of oily wastewater in low permeability oilfield.

Investigation on the simultaneous loss of saccharides in pre-hydrolysis liquor during an efficiently combined process towards lignin removal

Generally, lignin separation from prehydrolysis liquor (PHL) is accompanied by sugar removal, making the purification of PHL challenging. However, how sugar loss from PHL can be minimized in PHL purification is still unclear. In this work, a method for removing lignin from PHL was attested, which included treatments of PHL with poly aluminum chloride (PAC), activated carbon, and XAD-4 resin. The results exhibited that the PAC could form complexation with lignin facilitating lignin removal from PHL. At the PAC concentration of 15 mg/L, 10% of lignin was removed, while no significant sugar loss was observed. Subsequently, by treating PHL with activated carbon, 87% of the remaining lignin was removed from the PHL, while sugar loss was identified to be 14%. XAD-4 resin treatment could slightly improve the lignin removal from 87% to 92%. However, the XAD-4 was unselective in sugar removal and led to an increased sugar loss (from 14% to 37%). Interestingly, removing colloidal lignin by PAC benefited the subsequent activated carbon process for improving lignin removal. In other words, PAC removed not only colloidal lignin but also facilities lignin isolation (i.e., an increase from 81% to 87%) and prohibited sugar loss (a drop from 27% to 6%) in the subsequent activated carbon treatment.

직분사 DAF 공정을 이용한 정수장 유입 원수의 탁도 및 SS 제거특성

This research examines the installation and operation of a direct-spraying dissolved air flotation process to remove turbidity and SS (Suspended solids) in the pulsator clarifier of A water treatment plant in B city. To evaluate the performance of the direct-spraying DAF (Dissolved Air Flotation) process, experiments were conducted with raw water before chemical input. As polymer coagulants, Alum (Aluminum sulfate) and PAC (Poly aluminum chloride) are selected in this research, as these are the most widely used in water treatment processes. Installation scales on the site are 50,000 m³/d of water treatment capacity of the direct-spraying DAF process, and 10,000 m³/d of the wastewater treatment process. For raw water before PAC is added, turbidity and SS removal efficiency of the direct-spraying DAF process at several PAC concentrations (8 mg/L, 15 mg/L, 20 mg/L and 30 mg/L, respectively) are highest at the PAC concentration of 20 mg/L. In particular, during the trial run, the mean turbidity removal efficiency was 91.0 % at the optimum PAC concentration of 20 mg/L in raw water before chemical input.

Molecular insights into membrane fouling caused by polysaccharides with different structures in polyaluminum chloride coagulation-ultrafiltration process

In this study, mechanisms of membrane fouling caused by polysaccharides with different molecular structures in polyaluminum chloride (PACl) coagulation-ultrafiltration (C-UF) process were explored. Carrageenan and xanthan gum were chosen for model foulants of straight chain and branched chain polysaccharides, respectively. Filtration experiments showed that, with PACl dosage of 0–5 mM, specific filtration resistance (SFR) of carrageenan and xanthan solution showed a unimodal pattern and a continuous decrease pattern, respectively. A series of experimental characterizations indicated that the different SFR pattern was closely related to structure of foulants layer. Density functional theory (DFT) calculation suggested that Al3+ preferentially coordinating with the terminal sulfonyl groups of carrageenan chains to promote gel layer formation at low PACl concentration (0.15 mM). There existed a chemical potential gap between bound water in gel layer and free water in the permeate, so that, filtration through gel layer corresponded to rather high SFR for overcoming this gap. In contrast, Al3+ coordinating with the non-terminal sulfonyl groups of carrageenan at high PACl concentration caused transition from gel layer to cake layer, leading to SFR decrease. However, xanthan gum itself can form a dense gel layer with a complex polymer network by virtue of the interlacing of main chains and branches. Al3+ coordinating with the carboxyl groups on branched chains of xanthan gum resulted in clusters of polymer chains and flocculation, corresponding to the reduced SFR. This proposed molecular-level mechanism well explained membrane fouling behaviors of polysaccharides with different molecular structure, and also facilitated to optimize C-UF process for water treatment.

Optimizing dose of coagulant and pH values for membrane fouling control in a submerged membrane bioreactor

AbstractBACKGROUNDThis study assessed the impact of using polyaluminum chloride (PAC) and of changing pH values on the removal efficiency and membrane fouling in a submerged membrane bioreactor (MBR) system utilized to treat real pharmaceutical wastewater.RESULTSThe results revealed that sweep coagulation and a neutral pH were suitable for decreasing soluble microbial products (SMP) in the activated sludge, and the sludge filterability performed better with bridging coagulation and an acidic pH (6.5 < pH < 7). In addition, it was found that membrane fouling was greatly alleviated when PAC was added under the optimized conditions to the MBR (PAC concentration = 100 mg L−1 and pH = 7). Further analyses of membrane fouling mechanisms indicated that adding PAC to the MBR increased the biomass floc size and reduced the SMP concentration and the carbohydrate content in the mixed liquor.CONCLUSIONThe detailed analyses of the membranes' cake layers showed that the presence of PAC decreased the amount of fluorescent organic carbons, proteins, and carbohydrates. These changes in sludge characteristics considerably contributed to the reduction of reversible and irreversible membrane fouling. © 2022 Society of Chemical Industry (SCI).

Poly Aluminum Chloride (PAC) as Coagulant in Liquid Waste Treatment of Tofu

The tofu craftsmen have not processed the liquid waste produced and disposed of the liquid waste directly into the waters as a result, the water quality has decreased. Tofu liquid waste has BOD (Biological Oxygen Demand), COD (Chemical Oxygen Demand), and TSS (Total Suspended Solid) exceeding the permitted quality standards. Treatment of tofu liquid waste needs to be done before being disposed of, one of which is by using coagulant. The purpose of this research is to know the value of BOD, COD, TSS, and pH of tofu liquid waste before and after the addition of PAC. The study was conducted by varying the concentration of PAC (10 mg/L, 30 mg/L, and 75 mg/L). The test results show that the tofu liquid waste has a BOD value of 3,890 mg/L, COD 9558.7 mg/L, TSS 2,905 mg/L, and a pH of 3.7. The use of PAC as a coagulant reduced the values of BOD, COD, TSS, and pH. PAC concentration of 75 mg/L can reduce BOD, COD, TSS, and pH values to 3,015 mg/L, 6,900 mg/L, 840 mg/L, and 3.59, respectively.

Understanding the effect of residual aluminum salt coagulant on activated sludge in sequencing batch reactor: Performance response, activity restoration and microbial community evolution

To investigate the effect of residual coagulant after coagulation pretreatment on activated sludge system of wastewater treatment plants (WWTPs), comparative evaluation of lab-scale sequencing batch reactors under different poly-aluminum chloride (PAC) concentrations (20 and 55 mg/L), presenting the performance differences of reactors. Results showed that the PAC concentration of 20 mg/L slightly enhanced the average removal efficiencies of chemical oxygen demand (COD) and total nitrogen (TN), up to 93.43% and 72.52%. Whereas, an inhibition effect was exerted at the PAC concentration of 55 mg/L, the average removal efficiencies decreased to 88.56% and 57.80% respectively. Similarly, the residual aluminum salts showed a concentration effect of low promotion and high inhibition on sludge activity index. The content of specific oxygen utilization rate (SOUR) and dehydrogenase (DHA) sharply decreased by 30.17% and 53.56% under the high PAC concentration of 55 mg/L. Activity recovery phase showed that the suppression of aluminum salt coagulant on biological system was reversible. High-throughput sequencing presented that the relative abundance of microbes showed obvious variations at different PAC concentrations, and certain bacteria in Chloroflexi and Bacteroidota exhibited better adaptability to the high PAC concentration environment. Nevertheless, the antagonism action between denitrifying genera and other genera as well as the downregulation of functional enzymes regarding nitrogen metabolism gave rise to the deterioration of denitrification under the high PAC concentration of 55 mg/L. This study revealed the influence mechanism of residual aluminum salt coagulant on activated sludge system, providing strategies for efficient decontamination and long-term stable operation of biological system in wastewater treatment plant under the condition of adding PAC.

Experimental application of a zero-point charge based on pH as a simple indicator of microplastic particle aggregation

Micro/nanoplastics – a useful but threatening material – continuously require fundamental research on its behaviors and properties for aggregation. Zeta potential (ζ) has been using as an indicator to determine the optimal aggregation for particle removal in water treatment processes. In the field work, however, an alternative method for streamlining these tasks and reducing the variability in processing efficiency is necessary. To improve practical utility in the field work, this study aimed at investigating applicability of the zero-point charge (ZPC) of the isoelectric point (IEP; ψpI) as an alternative indicator for aggregation in place of ζ. For the purpose, this study conducted laboratory experiments and model simulations. The experiments measured ψpI of microplastics in a trivalent-electrolyte aqueous solution using various concentrations of polyaluminum chloride (PAC) for reproducing the behavior of microplastics in natural water environments. As a result, ψpI for polyethylene (PE) and polyvinylchloride (PVC) were found to be pH 6.59 and 6.43, respectively. The removal rates (r) depended on the aggregation at the initial pH and optimal PAC concentration. The experimental attachment efficiency (αE), 0.14 to 0.4, showed a good correlation of over 95% with r, 0.04 to 0.84, both based on the pH change and PAC concentration and differing slightly with the type and size of the plastic. The highest αE was achieved with the highest r when ψpI was close to zero in the pH range of 6–8 using the optimized PAC concentration. Based on the experimental results, the model confirmed the applicability of ψpI instead of ζ as an indicator of the aggregation by simulating αE based on ψpI and ionic strength, which are themselves based on the change in pH. Therefore, this study provides some insights into behaviors of microplastics by using the isoelectric point (IEP, ψpI) as an indicator of aggregation of microplastics in place of ζ. The IEP method is limited by initial pH, optimal dosage of coagulant, and type and size of microplastics, but it will increase practical utility in the field.

Characteristics of raw water sources and analysis of the optimal model of the mixing process with parameter design in clean water pump installations

The quality characteristics of raw water sources in the regional integrated drinking water supply system (SPAM) of Banjarbakula were investigated and found to maintain the supply of drinking water quantity and quality in accordance with drinking water standards. The optimum model for the mixing process of raw water and poly aluminum chloride (PAC) and pump stroke for the input of water sources from rivers to obtain a composition setting that is in accordance with the raw water sources of each region in the region was selected and determined. So the optimum parameter setting model between alum water, raw water and pump stroke for each raw water source is known and is regionally integrated as a result of a comprehensive study. The integration of Taguchi parameter design and response surface can complement each other and become two methods that go hand in hand in the process of optimizing clean water products. Parameter design provides a very practical optimization step, the basis for this formation refers to the factorial fractional experimental design. However, the absence of statistical assumptions that follow the stages of analysis makes this method widely chosen by researchers and practitioners. With the experimental design of the raw water mixing process, turbidity such as 5 lt/sec, 10 lt/sec, 15 lt/sec, 20 lt/sec and 25 lt/sec and % PAC concentration 5 ppm, 10 ppm, 15 ppm, 20 ppm and 25 ppm with a pump installation stroke of 5 %, 10 %, 15 %, 20 % and 25 % were used. In the process of adding PAC, always pay attention and observe the behavior of the attractive force of the floating particles (flock). The particles were then subjected to SEM (scanning electron microscopy) to determine the dimensions of the flock grains deposited

A rapid and simple protocol for concentration of SARS-CoV-2 from sewage

The aim of this study was to set up a simple protocol to concentrate SARS-CoV-2 from sewage, which can be implemented in laboratories with minimal equipment resources. The method avoids the need for extensive purification steps and reduces the concentration of potential inhibitors of RT-qPCR contained in sewage. The concentration method consists of a single step, in which a small volume (40 mL) of sewage sample is incubated with polyaluminum chloride (PAC)(0.00045 N Al3+ final concentration). Virus particles adsorbed to the precipitate are collected by low-speed centrifugation, after which the recovered pellet is resuspended with a saline buffer. PAC-concentrated samples are stable for at least one week at 4 °C. Therefore, they may be sent refrigerated to a diagnosis center for RNA extraction and RT-qPCR for SARS-CoV-2 RNA detection if the lab does not have such capabilities. The PAC concentration method produced an average shift of 4.5-units in quantification cycle (Cq) values compared to non-concentrated samples, indicating a 25-fold increase in detection sensitivity. The lower detection limit corresponded approximately to 100 viral copies per ml. Kappa index indicated substantial agreement between PAC and polyethylene glycol (PEG) precipitation protocols (k = 0.688, CI 0.457−0.919). This low-cost concentration protocol could be useful to aid in the monitoring of community circulation of SARS-CoV-2, especially in low- and middle-income countries, which do not have massive access to support from specialized labs for sewage surveillance.

Chemical coagulation-electro fenton as a superior combination process for treatment of dairy wastewater: performance and modelling

Dairy wastewater contains high levels of organic matter that would be a serious threat if being discharged to the environment without any treatment. This study investigated the influence of various parameters including the concentration of poly aluminum chloride (PAC) on the chemical coagulation process and the concentration of H2O2, pH of the solution, reaction time, voltage and distance of electrodes in the electro-Fenton (EF) process. The optimum conditions obtained in this study included PAC concentration of 100 mg/L, pH of 3, reaction time of 60 min, voltage of 20 V, H2O2 concentration of 1.5 g/L and electrode distance of 2 cm. This resulted in the removal efficiency of 90.3%, 87.25%, and 87% for chemical oxygen demand (COD), biochemical oxygen demand (BOD5), and total suspended solids, respectively. The estimated cost of the process in terms of 1 kg COD removal was about $1.16. Two experimental models, called the feed-forward artificial neural network (FF-ANN) and partial least squares (PLS), were developed to predict the behavior of the process in COD removal. The results confirmed that both FF-ANN and PLS were powerful tools in predicting COD removal in the EF process, as the correlation coefficients between the predicted COD and the actual COD for the PLS and FF-ANN models were 0.854 and 0.971, respectively. Sensitivity analysis of both models showed that the reaction time and electrode distance had the most influence on the output of PLS and FF-ANN, respectively. Therefore, this combined process can be regarded as a thought-provoking one for dairy wastewater treatment, and the FF-ANN model was a more powerful tool than the PLS one.

Coupling effect of ozone/ultrasound with coagulation for improving NOM and turbidity removal from surface water

This study investigates the effects of ultrasound–ozonation (US/O3) pretreatment combined with coagulation on the natural organic matter (NOM) and turbidity removal from surface waters.The influence of US/O3 alone and US/O3-coagulation on the removal of NOM and turbidity was measured by testing total organic carbon (TOC) fractionation and UV absorbance at 254 (UV254) and using a turbidimeter. Aluminum sulfate (alum), ferric chloride (FC), and poly aluminum chloride (PACl) were used as coagulants. The disinfection efficiency of the process was studied using total coliforms and bromate concentration was analyzed to examine the formation of disinfection byproducts (DBPs).The US/O3 process led to 84%, 33%, and 46% removal of the NOM, turbidity and TOC, respectively. However, a combination of US/O3 with coagulation increased the removal efficiency to 95% and 50% and 75%, respectively. The optimum working conditions of the US/O3-coagulation process was US frequency of 80 kHz, power intensity of 200 W/cm2, ozone dosage of 3 mg/L, reaction time of 8.06 min, PACl concentration of 0.81 mg/L, and 0.1 mg/L of coagulant aid. Chemical fractionation showed that the US/O3-coagulation could transform the NOM macromolecules into smaller and lighter compounds. No diagnosis of total coliform or E. coli was detected in samples treated by the US/O3-coagulation process. Moreover, treatment with this process did not increase the bromate concentration.According to the results, pretreatment with US/O3 significantly improves the coagulation process for NOM, TOC, coliform, and turbidity removal. Therefore, the US/O3-coagulation process has the potential to be considered as an efficient water treatment method.

Colloidal biliquid aphron demulsification using polyaluminum chloride and density modification of DNAPLs: optimal conditions and common ion effect.

Dense non-aqueous phase liquids (DNAPLs) entrapped and pooled in aquifers serve as a long term source of groundwater contamination because of their low solubility and high density. Density modification displacement (DMD) with colloidal biliquid aphrons (CBLAs) is a promising approach to prevent DNAPL downward migration during surfactant-based remediation processes. CBLA demulsification and quick release of internal light organic matter is the key to density modification of DNAPLs. In this work, it is reported for the first time that polyaluminum chloride (PAC) could destabilize CBLAs efficiently. The optimum conditions for demulsification of CBLAs by PAC were obtained; the effects of several specific ions in groundwater on demulsification of CBLAs by PAC were investigated. The results indicated that the CBLA was completely demulsified by PAC within 10 minutes and released light organic matter. It recorded the highest demulsification efficiency when the addition ratio (VPAC/VCBLA) was 2 : 1, concentration of PAC was 0.7 g L-1 and the PVR of CBLAs was 8. Most cations (sodium, magnesium and calcium ions) had inhibitory effects on demulsification of CBLAs by PAC with increasing ion concentration, but iron ions had no effect on it. Sulfate anions showed a stronger inhibitory effect on demulsification of CBLAs by PAC compared to chloride ions. With PAC as the demulsifier, CBLAs could be demulsified efficiently, irreversibly modifying the density of trichloroethylene in 5 minutes.

OPTIMIZATION OF THE ALUMINUM SULFATE AND PAC (POLY ALUMINUM CHLORIDE) COAGULANT ON TELLO RIVER WATER TREATMENT

Abstract- Tello River water used by PT. PLN SULTANBATARA for sanitation and process water. One of the process's water is boiler feed water. River water has fluctuative characteristics depending on the season that occurs such as turbidity and Total Suspended Solid (TSS). The presence of TSS in boiler feed water needs to be minimized as it can decrease boiler performance in generating heat. The concentration of TSS in river water can be removed by coagulation and flocculation method with the addition of coagulant. Excessive coagulant distribution will increase the concentration of dissolved solids (TDS) of water. Thus, it is necessary to determine the optimum concentration of coagulant based on initial TSS concentration of river water. The objective of this research is to determine the optimum concentration of Aluminum Sulfate (Al2(SO4)3) and PAC (Poly Aluminum Chloride) Coagulant in reducing TSS water of Tello River. The sample used in this research is Tello river water which has an initial TSS concentration of 150 mg/L. The coagulant used was Aluminum Sulfate and PAC with several concentration variation of 5% - 40% to the initial TSS concentration of river water. Analysis of TSS content of samples using Gravimetry method. The optimum concentration of coagulant Aluminum Sulfate and PAC was 35% and 25% to the initial TSS concentration of river water where the final concentration of TSS obtained was 20 mg/L and 15.5 mg/L with percent TSS removal of 86.67% and 89.6 %. Keywords: Total Suspended Solid, Coagulation, Aluminium Sulfate, Poly Aluminium Chloride (PAC)

Regulating the Interlayer Spacing of Graphene Oxide Membranes and Enhancing their Stability by Use of PACl.

Graphene oxide (GO) is an ideal membrane material for water treatment due to its outstanding physicochemical properties and unique lamellar structure. However, the separation performance and practical application of GO membranes are mainly affected by the interlayer spacing and stability in aqueous solutions. Here, we report a novel and facile approach to fabricating GO membranes with adjustable interlayer spacing and high stability in aqueous solutions through cross-linking with polyaluminum chloride (PACl). With this approach, the lamellar spacing can be adjusted by changing the OH/Al ratios (B values) of the PACl, and the GO nanosheets can be tightly bonded by the strong electrostatic effect that PACl provides between them. The average interlayer spacing of the GO layer could be varied approximately in the range of 0.80-1.09 nm. The PACl-GO membranes demonstrated excellent stability in water and inorganic/organic solutions when the concentration of PACl was 0.1, 1, and 10 mM, remaining unchanged for at least 2 weeks. Moreover, the PACl-GO membranes featured exceptional sieving capabilities for model and natural organic substrates, while it was also observed that increasing the interlayer spacing of the PACl-GO membranes increased both the membrane flux and the separation performance of organic matter.

OPTIMIZATION OF THE ALUMINUM SULFATE AND PAC (POLY ALUMINUM CHLORIDE) COAGULANT ON TELLO RIVER WATER TREATMENT

Abstract- Tello River water used by PT. PLN SULTANBATARA for sanitation and process water. One of the process's water is boiler feed water. River water has fluctuative characteristics depending on the season that occurs such as turbidity and Total Suspended Solid (TSS). The presence of TSS in boiler feed water needs to be minimized as it can decrease boiler performance in generating heat. The concentration of TSS in river water can be removed by coagulation and flocculation method with the addition of coagulant. Excessive coagulant distribution will increase the concentration of dissolved solids (TDS) of water. Thus, it is necessary to determine the optimum concentration of coagulant based on initial TSS concentration of river water. The objective of this research is to determine the optimum concentration of Aluminum Sulfate (Al2(SO4)3) and PAC (Poly Aluminum Chloride) Coagulant in reducing TSS water of Tello River. The sample used in this research is Tello river water which has an initial TSS concentration of 150 mg/L. The coagulant used was Aluminum Sulfate and PAC with several concentration variation of 5% - 40% to the initial TSS concentration of river water. Analysis of TSS content of samples using Gravimetry method. The optimum concentration of coagulant Aluminum Sulfate and PAC was 35% and 25% to the initial TSS concentration of river water where the final concentration of TSS obtained was 20 mg/L and 15.5 mg/L with percent TSS removal of 86.67% and 89.6 %. Keywords: Total Suspended Solid, Coagulation, Aluminium Sulfate, Poly Aluminium Chloride (PAC)

OPTIMIZATION OF THE ALUMINUM SULFATE AND PAC (POLY ALUMINUM CHLORIDE) COAGULANT ON TELLO RIVER WATER TREATMENT

- Tello River water used by PT. PLN SULTANBATARA for sanitation and process water. One of the process's water is boiler feed water. River water has fluctuative characteristics depending on the season that occurs such as turbidity and Total Suspended Solid (TSS). The presence of TSS in boiler feed water needs to be minimized as it can decrease boiler performance in generating heat. The concentration of TSS in river water can be removed by coagulation and flocculation method with the addition of coagulant. Excessive coagulant distribution will increase the concentration of dissolved solids (TDS) of water. Thus, it is necessary to determine the optimum concentration of coagulant based on initial TSS concentration of river water. The objective of this research is to determine the optimum concentration of Aluminum Sulfate (Al 2 (SO 4 ) 3 ) and PAC (Poly Aluminum Chloride) Coagulant in reducing TSS water of Tello River. The sample used in this research is Tello river water which has an initial TSS concentration of 150 mg/L. The coagulant used was Aluminum Sulfate and PAC with several concentration variation of 5% - 40% to the initial TSS concentration of river water. Analysis of TSS content of samples using Gravimetry method. The optimum concentration of coagulant Aluminum Sulfate and PAC was 35% and 25% to the initial TSS concentration of river water where the final concentration of TSS obtained was 20 mg/L and 15.5 mg/L with percent TSS removal of 86.67% and 89.6 %. Keywords: Total Suspended Solid, Coagulation, Aluminium Sulfate, Poly Aluminium Chloride (PAC)