Natural Coagulant Aid Research Articles

Development and techno-economic analysis of Grewia biopolymer-based dual coagulant system for wastewater treatment at pilot scale

Use of Grewia biopolymer as a natural coagulant aid was explored in a dual-coagulant system (conventional coagulant + biopolymer) for wastewater treatment. Such use not only improved turbidity removal efficiency over a wide pH range (5–9) but also helped reducing the concentration demand of inorganic coagulants by 25–50 %. Response surface methodology was employed for investigating the interaction between factors (initial pH, coagulant, and biopolymer concentration) affecting coagulation/flocculation of aqueous laterite suspension, and process optimization for more than 80 % turbidity removal in the desired final pH range (6–7). Mechanisms potentially involved in coagulation/flocculation using biopolymer was elucidated. Techno-economic assessment indicated the feasibility of pilot-scale production of the biopolymer and its use in wastewater treatment. This study demonstrates that Grewia biopolymer has the potential to be used as a coagulant aid and will help researchers select appropriate markets for further cost reduction and successful implementation of biopolymer-based wastewater treatment.

Effect of Gum Arabic on the Clarity of Artificially Turbid Water and Ground Water Systems

The high cost of using synthetic polymers such as polyacrylamides in the water purification process, and their monomers toxicity produced from the polymer synthesis encouraged many researchers to find a good replacement to clarify turbid water. This work was carried out to determine the effectiveness of Gum Arabic (GA) as a natural coagulant aid in the treatment of artificially turbid water (water saturated with silica (SiO2), the main component of rocks) and ground drinking water systems, which is rich in rocks. The experimental results showed that the highest efficiency for GA as a water clearer was increased by increasing its content to 5 wt %. This was confirmed by a reduction in the turbidity from 1269 NTU to 56 NTU. Interaction kinetic fits specified that the two-phase decay model was found to be the proper fit (R2 ~ 1) for the kinetic data at 0.001, 0.01, 0.1 wt% of added GA. This proposes that at a low content of GA molecules, some SiO2 particles remain suspended in bulk solution, while only one phase decay fitted the data well when 1 and 5 wt% of GA were added, which means a complete GA-SiO2 interaction. Furthermore, the turbidity decay dependence on the GA content was noted as a minimum interaction lifetime (τ = 9 min) has been observed at 5 wt%. The physicochemical analyses have revealed that GA is effective in reducing turbidity, total dissolved solids, total alkalinity and total hardness of water and has the ability for water purification by owning unwanted minerals and hardness removal characteristics. This eco-friendly and economical natural polymer could be a promising material to use in groundwater treatment.

The Utilization of Pectin as Natural Coagulant-Aid in Congo Red Dye Removal

Coagulation using inorganic compounds such as aluminum sulfate is commonly used in water-wastewater treatment. However, there are some drawbacks to its utilization, such as a significant decrease in the treated water’s pH, non-biodegradable sludge, and a potential negative impact on human mental health (dementia and Alzheimer's). The use of inorganic coagulants can be minimized with the addition of natural-based coagulant-aid such as pectin. In this study, Congo red solution, a model dye substance, was coagulated by varying the pH (3–7) using alum coagulant to determine the best pH for coagulation. At the best pH, pectin was introduced at various doses (0–30 mg/L), and subsequently various dye concentrations (50–100 mg/L). The effect of pectin as coagulant-aid was compared with aluminum sulfate and pectin only; with a response of %removal and sludge volume. It was found that the Congo red dye coagulation had the best %removal at pH 6 indicating a charge neutralization mechanism. The addition of 15 mg/L pectin at an aluminum sulfate dose of 30 mg/L resulted in 97.7% dye removal with a sludge volume of 14 mL/L at a Congo red concentration of 50 mg/L. This value is higher compared to those of aluminum sulfate and pectin only which gave 75.6 and 3.19% removals, respectively. Furthermore, the addition of pectin as a natural coagulant-aid could halve the sludge volume due to the formation of denser flocs. The results show a promising potential of pectin as a natural coagulant-aid in water-wastewater treatment.

Modeling and optimization of the coagulation/flocculation process in turbidity removal from water using poly aluminum chloride and rice starch as a natural coagulant aid.

The application of the coagulation/flocculation process is very important due to its simplicity in removing turbidity. Due to the disadvantages of using chemical coagulants in water and the lack of sufficient effect of natural materials alone in removing turbidity for proper performance, the simultaneous use of chemical and natural coagulants is the best way to reduce the harmful effects of chemical coagulants in water. In this study, the application of poly aluminum chloride (PAC) as a chemical coagulant and rice starch as a natural coagulant aid to remove turbidity from aqueous solutions was investigated. Effects of the above coagulants on the four main factors, coagulant dose (0-10mg/L), coagulant adjuvant dose (0-0.1mg/L), pH (5-9), turbidity (NTU 0-50), and each five levels were assessed using a central composite design (CCD). Under the optimized conditions, the maximum turbidity elimination efficiency was found to be 96.6%. The validity and adequacy of the proposed model (quadratic model) were confirmed by the corresponding statistics (i.e., F-value of 23.3, p-values of 0.0001, and lack of fit of 0.877 for the model, respectively, R2 = 0.88, R2adj. = 0.84, R2 pred = 0.79, AP = 22.04).

Influence of Particle Size and Zeta Potential in Treating Highly Coloured Old Landfill Leachate by Tin Tetrachloride and Rubber Seed.

Old leachate normally has a low organic compound content, poor biodegradability and is hard to biologically treat. The efficacy of tetravalent metal salts as a coagulant and the application of a natural coagulant as a flocculant in landfill leachate treatment is still inconclusive. Hence, this study aimed to evaluate the potential application of tin tetrachloride (SnCl4) as the main coagulant and the rubber seed (Hevea brasiliensis) (RS) as the natural coagulant aid as the sole treatment in eradicating highly coloured and turbid stabilised landfill leachate present at one of the old local landfills in Malaysia. The standard jar test conducted revealed that SnCl4 was able to eliminate 99% and 97.3% of suspended solids (SS) and colour, respectively, at pH8, with 10,000 mg/L dosages, an average particle size of 2419 d·nm, and a zeta potential (ZP) of −0.4 mV. However, RS was found to be ineffective as the main coagulant and could only remove 46.7% of SS and 76.5% of colour at pH3 with 6000 mg/L dosages, and also exhibited smaller particles (933 d·nm) with ZP values of −6.3 mV. When used as a coagulant aid, the polymer bridging mechanism in RS helped in reducing the SnCl4 concentration from 10,000 mg/L to 8000 mg/L by maintaining the same performances. The presence of 1000 mg/L RS as a coagulant aid was able to remove 100% of SS and 97.6% of colour. The study concluded that RS has the potential to be used together with SnCl4 in treating concentrated leachate with SS and colour.

A Study on Dragon Fruit Foliage as Natural Coagulant and Coagulant Aid for Water Treatment

Due to the heavy pollution all over the world, quality has decreased in nature. Water is the most essential in everyone’s life. The contamination of water with organic and inorganic matters are harmful to the society. Turbidity is caused by these matters which are colloidal and suspended solids and there is a requirement to remove these matters for the water to be useful. Coagulation and flocculation are the most generally picked strategies to reestablish acceptability and work on the tasteful appearance of water. This procedure brings about the colloidal particles destabilization and therefore, the addition in molecule size for the simplicity of sedimentation. Currently the treatment units are using chemical coagulants such as aluminum and iron salts which work most effectively. The most used coagulant, Alum has been a centre of debate as various researchers say it is linked to development of Alzheimer’s disease. Also, other chemical coagulants are evident of causing throat tightness, shallow ulcers on skin etc. In addition to these effects on human health, the chemical coagulants produce hazardous sludge which requires a costly disposal. Various naturally available materials have the properties that make them effective coagulants that are chemically neutral and purify water competitively with their coagulant counterparts. In this investigate, dragon fruit foliage is used as a natural coagulant and proved that it is competitive with chemical coagulant in removal of turbidity.

Investigating the Efficiency of Natural Coagulant Aid (Tragacanth) with PAC in Removal of Turbidity and Coliform Bacteria from Karoon River Water

Investigating the Efficiency of Natural Coagulant Aid (Tragacanth) with PAC in Removal of Turbidity and Coliform Bacteria from Karoon River Water

Binary coagulation system (graphene oxide/chitosan) for polluted surface water treatment

In this study, chitosan (CS) is used as a natural coagulant aid alongside graphene oxide (GO) to remove turbidity and numerous pollutants from raw and artificially contaminated surface water. The coagulation capability of the system (GO/CS) was assessed with respect to a water sample's turbidity, pH, coagulant dose, settling velocity, and temperature. The presence of CS enhanced the coagulation capacity of GO at varied pH levels and no GO residue was detected in the water after the treatment. The proposed system achieved high turbidity removal efficiency (≥98.3%) for all turbidity levels. A mixture of GO (8 mg/L) and CS (2 mg/L) was ideal to remove algae (99.5%) and bacteria (≥95.0%). Furthermore, it demonstrated a high coagulation capacity to remove dyes, direct brown-2 (DB-2), methylene blue (MB), and Pb(II) ions from artificially contaminated surface water. Interestingly, the sludge exhibited an extraordinary adsorption capacity for DB-2, MB, and Pb(II) ions. The adsorption process followed the pseudo-second-order kinetic model, and was consistent with the Langmuir model, with an adsorption capacity of up to 667.8, 400.7, and 459.1 mg/g for DB-2, MB, and Pb(II) ions, respectively. Therefore, the presented binary coagulation system is of great potential economic value for the treatment of raw surface water and wastewater.

Synthesis and application of coagulant derived from <i>Durio zibethinus</i> for emerging contaminants removal from landfill leachate

As an alternative of coagulant based aluminium (Al) in landfill leachate treatment, starch-based coagulants have been synthesised from Durio zibethinus seed starch (DSS) and studied for its potential as a natural coagulant and coagulant aid in the presence of PACl to remove organic matter and heavy metal using coagulation and flocculation process. Leachate sample was sampled from Larut Matang landfill, Perak, Malaysia. The optimum DSS dosage was 360 g/L at pH 9. The addition of DSS as a coagulant aid improved the removal rate of colour, turbidity and zinc. However, the addition of DSS as a coagulant aid increased the concentration of manganese by 15%. It was assumed that PACl was more superior than DSS for the removal of turbidity, colour, COD and iron removal. In conclusion, DSS has the potential to be a coagulant aid in coagulation and flocculation based on their removal efficiency values.

Effectiveness of alhagi maurorum as natural coagulant aid in grey wastewater treatment study

The Alhagi Maurorum (AM) is used as a coagulant aid to support the action of coagulant factor in grey water treatment; alum could be accounted as the mean chemical coagulant and Alhagi Maurorum (in two separated forms: powdered and extracted liquid) as the coagulant aid. A series of experiments were managed to find the optimum dosage of AM and optimum pH condition so as to achieve higher removal efficiencies for the contaminants such as turbidity, chemical oxygen demand (COD) and total suspended solids (TSS) originated in synthetic grey wastewater. Using AM as an extracted liquid was better than the powdered form. The results showed that the combination of 40 mg/l of alum and 1.0 ml/L of extracted liquid AM achieved reduction efficiency for (Turbidity, COD and TSS) by (98%, 92%, 95%) at pH=10. The results showed the possibility of the application of AM as natural coagulant. The positive impact or possibility of the application of AM as natural coagulant

Enteromorpha prolifera polysaccharide based coagulant aid for humic acids removal and ultrafiltration membrane fouling control

Polyacrylamide (PAM) has been used as a coagulant aid in water treatment process for past decades, but it has caused great damages to human nervous system. Developing new coagulant aid with high biological safety is urgently demanded. This study provides a natural biomacromolecule coagulant aid with good biosecurity-Enteromorpha prolifera polysaccharide (Ep). Its coagulant aid efficiency and mechanism were investigated in terms of organics removal, floc properties and membrane fouling degree. In addition, contrast experiments were conducted with PAM to evaluate its potential of industrial applications. Results showed that organics removal could be increased by 23% when 0.3 mg/L Ep was used, which exhibited comparable aid effects to PAM. Due to the bridging-sweep aid role of Ep, flocs sizes, growth rate and recovery factor reached 470 μm, 62.6 μm/min and 0.492, respectively, while only 170 μm, 14.0 μm/min and 0.326 were obtained by PAM. Additionally, flocs exhibited more porous and multi-branched structures when Ep was applied, which caused less ultrafiltration membrane fouling (eventual J/J0 value = 0.52). As a result, Ep could be considered as a potential substitute of PAM, since better biosecurity, higher organics removal and lower membrane fouling could be obtained simultaneously by Ep addition.

Potential Use of Dimocarpus longan Seeds as a Flocculant in Landfill Leachate Treatment

Landfill leachate is a highly polluted and generated from water infiltration through solid waste produced domestically and industrially. In this study, a coagulation–flocculation process using a combination of Polyaluminium chloride (PACl) as a coagulant and Dimocarpus longan seed powder (LSP) as coagulant aid was used in treating landfill leachate. LSP has been tested as the main coagulant and as coagulant aid with PACl. As the main coagulant, the optimum dosage and pH for PACl were 5 g/L and 6, respectively, with removal efficiencies of 67.44%, 99.47%, and 98% for COD, SS, and color, respectively. For LSP as the main coagulant, results show that LSP is not effective where the removal efficiencies obtained for COD, SS, and color were 39.40%, 22.20%, and 28.30%, respectively, with the optimum dosage of 2 g/L and pH 4. The maximum removal efficiencies of COD, SS, and color were 69.19%, 99.50%, and 98.80%, respectively, when LSP was used as coagulant aid with PACl. Results show that using LSP as coagulant aid was found to be more effective in the removal of COD, SS, and color with less PACl dosage. The PACl dosage was decreased from 5 to 2.75 g/L when LSP was used as a coagulant aid. Cost estimation for using PACl alone and using LSP as the coagulant aid showed a reduction in the cost of approximately 40% of the cost of using PACl alone. Overall, this study confirmed the efficiency of LSP to be used as a natural coagulant aid in leachate treatment.

Garden cress mucilage as a potential emerging biopolymer for improving turbidity removal in water treatment

Abstract Agricultural anthropogenic processes have resulted in high turbidity to nearby river water. This study aims to study the possibility and mechanism of biopolymer extracted from garden cress (Lepidium Sativum sp.) seed as natural coagulant aid in a point source agriculture wastewater discharge. Various physico-chemical characterisation studies were conducted i.e. functional group, zeta potential and surface floc morphology. FTIR spectra results indicated the biopolymer was assigned to band peaks at for hydroxyl, carboxyl groups. Whilst, zeta potential was around −16 mV, describing its anionic nature. The morphologies study depicted that the addition of biopolymer produced a more compact and larger structure of the settled sludge. Influence of pH, dosage of Fe3+ and biopolymer were studied in synthetic kaolin and agricultural wastewater using factorial design. pH, dosage of Fe3+ and biopolymer significantly affect the turbidity removal in coagulation process with p-value

Effects of using Tamarindus indica Seeds as a natural coagulant aid in landfill leachate treatment

Uncontrolled landfill leachate generation portends danger to the environment and aquatic ecosystem, especially without prior treatment before discharge. The application of Al-based coagulants, such as polyaluminum chloride (PACl), has the potential of introducing Al residuals into water bodies. Therefore, an alternative natural coagulant was recommended to reduce the usage of Al-based coagulants. In this study, a coagulation–flocculation process using the combination of PACl as coagulant and Tamarindus indica seed (TiS) as coagulant aid was used in treating the landfill leachate from the Alor Pongsu Landfill Site in Malaysia. Some of the optimum operational conditions determined were the pH and dosage of the coagulant aid, and their effect was considered on parameters, such as suspended solids (SS), color, and COD, using standard jar test procedures. The combination of TiS flocculant reduced the dosage of PACl coagulant from 5,000 mg/L to 2,750 mg/L with removal efficiencies of 99.3%, 97.3%, and 67.4% for SS, color, and COD, respectively.

Enhancing Electrocoagulation Process Efficiency Using Astraglus Gossypinus Tragacanth in Turbidity Removal from Brackish Water Samples

Colloidal particles are the main cause of turbidity in an aquatic environment. Water turbidity maintains pathogenic microorganisms against disinfection. In addition to increasing the consumption of antiseptic substances, mainly it causes a lot of aesthetic and non-sanitary problems such as the formation of toxic and carcinogenic side constituents in the treatment of water. In this study we investigated the efficiency of the use of tragacanth of Astraglus gossypinus (Catira) on the effectiveness of the electrocoagulation process in the removal of turbidity from brackish water. In this descriptive-analytic study, direct bentonite injections of 2 to 8 g/L were used to provide opacity. In the following, the effect of applying coagulant aid of Tragacanth of Astraglus gossypinus plant with values of 0.25 to 1.5 g/L on the efficiency of the electro-coagulation process equipped with iron electrodes in the removal of opacity from brackish water samples were examined in potential difference from 5 to 30 volts, and pH from 2 to 9 over a period of 60 min. Variation of turbidity was determined using the turbidity sensor in accordance with standard reference methods. The results showed that the highest opacity removal efficiency is about 99 for each 1 kg of opacity due to the addition of 7 g/L bentonite under neutral pH conditions, Tragacanth dose of 1.5 g/L, 8 g/L dose of NaCl, and voltage of 30 V for 30 min, along with the average consumption of iron and electrical energy of 0.18 kg and 0.53 Kwh, respectively. Thus, the use of Astraglus gossypinus tragacanth for removing turbidity as a natural coagulant aid dramatically improves the electrocoagulation process efficiency in the removal of turbidity from brackish water samples and reduces current costs of the electro-coagulation process.

Effect of Opuntia ficus indica mucilage on copper removal from water by electrocoagulation-electroflotation technique

Electrocoagulation-electroflotation (EC-EF) process assisted with the mucilage of Opuntia ficus indica (OFI) plant was investigated in order to enhance copper removal efficiency. EC-EF tests with aluminum electrodes were conducted for the treatment of a synthetic copper solution of 100mg/L, to estimate the influence of the mucilage on removal of copper metal ions, aluminum and hydrogen Faradaic yields, settling process and specific electrical energy consumption. It was mainly found that: (i) copper removal efficiency reached 100% in <5min with 30mg/L OFI mucilage at pH7.8; (ii) OFI mucilage affected aluminum and hydrogen Faradaic yields at high removal efficiencies; (iii) copper sludge settling rate rises with increasing mucilage concentrations, and was enhanced by 15%; (iv) OFI mucilage reduced specific energy consumption at a fixed current density along with removal efficiency increase. Furthermore, the formed flocs, in the presence or not of mucilage, were identified by scanning electron microscope analysis (SEM). This work promotes the use of OFI mucilage as an active natural coagulant aid for the removal of copper species from water, by suggesting the substitution of chemical coagulants that are often added to the EC-EF technique.

New Natural Coagulant Aid in Water Treatment

Natural source of coagulant is certainly being considered in addressing the disadvantages associated with the use of inorganic coagulants. Annona muricata is hypothesized to be new material as natural coagulant aid in coagulation-flocculation process. On the other hand, due to the high lipids content in microalgae, namely, Chlorella vulgaris is used in producing renewable energy, i.e. biodiesel. Coagulation-flocculation is an effective method in microalgae harvesting. Thus, in this study, a novel natural coagulant aid extracted from fruit waste in algae harvesting. It is aimed to (1) to extract natural coagulant aid (hereafter is known as biopolymer) extracted from Annona muricata seeds in algae harvesting, and (2) to evaluate the operational conditions of coagulation-flocculation process by utilizing the biopolymer. As a result, it is observed that acid extraction and extraction through sodium chloride does not show any yield. On the other hand, the harvesting efficiency showed positive response as coagulant aid at 20 mg/L.

Application of Moringa oleifera coagulant protein as natural coagulant aid with alum for removal of heavy metals from raw water

Presence of aluminum residues in treated water has various health and environmental consequences such as neurotoxicity and possibly Alzheimer’s disease. This study investigated the effects of coagu-lation/flocculation/sedimentation processes using alum as a coagulant in conjunction with Moringa oleifera coagulant protein (MOCP) as coagulant aid on alkalinity and hardness as well as removal of metal ions and turbidity from turbid water. In this study, MOCP was synthesized and used as a new method of treating turbid water. A conventional jar test apparatus was utilized for the tests. Optimal dosage for MOCP was found at pH of 7–7.5 for all turbidities. Maximum turbidity removal of 99 was achieved. MOCP significantly reduced the required dosage of alum. The values of TOC in treated water in low, medium and high turbidity were 0.55, 0.5 and 0.65 mg L–1, respectively. The efficiency of metal ion removal in the present study was as follows: Fe2+ > Cu2+ > Zn2+ > Mn2+. We demonstrated that this method is an efficient approach for optimization of the coagulation-flocculation process in the treatment of raw water. © 2018 Desalination Publications. All rights reserved.

Optimum of Treatment Condition for &lt;i&gt;Artocarpus heterophyllus&lt;/i&gt; Seeds Starch as Natural Coagulant Aid in Landfill Leachate Treatment by RSM

Landfill still remains the most commonly employed treatment for municipal solid waste disposal around the world, which generates a high-strength wastewater with complex constituents referred to as landfill leachate. As consequences, if not properly treated and safely disposed, leachate can migrate into soil and subsoils which might cause severe damage to eco-system of land, surface water and groundwater. Aim of this paper is to establish the optimum parameters of starch-based coagulant as an alternative coagulant to remove suspended solid (SS), colour, turbidity, carbon oxygen demand (COD), and ammoniacal-nitrogen in leachate treatment by using RSM method. Leachate was collected from Matang Landfill Site, Perak, Malaysia. In this paper, the efficiency of Jackfruit seeds starch (JSS) act as a coagulant aid is established by using Kategunya method with percentage yield of 33.67%. The starch obtained is then used together with polyaluminium chloride (PAC) in leachate sample. The removal efficiency was determined by a series of experiments using jar test. By using three independent variables including pH, dosage of PAC and dosage of JSS for Central Composite Design (CCD) of RSM, optimum removal of response parameters is carried out. As a result, optimum removal of COD at pH 5, 523.32 mg/L of PAC, 400 mg/L of JSS gives Prob.&gt;F significantly with only 4.32% error. The results showed that, addition of JSS as coagulant aid also helps to reduce the dosage of PAC as well as JSS in leachate. As a conclusion, JSS can be used as a coagulant aid to PAC.

Extraction and application of starch-based coagulants from sago trunk for semi-aerobic landfill leachate treatment.

Malaysia is one of the highest starch producers. In this study, sago starch was utilized as a natural coagulant aid to reduce the dosage of aluminum-based coagulant in leachate treatment. The potential of native sago trunk starch (NSTS) and commercial sago starch (CSS) was evaluated as sole coagulant and coagulant aid in the presence of polyaluminum chloride (PACl) in the removal of color, suspended solids (SS), NH3-N, turbidity, chemical oxygen demand, organic UV254, Cd, and Ni. Leachate was sampled from Pulau Burung Landfill Site, one of the semi-aerobic landfills in Malaysia. The optimum dosage for PACl in the presence of NSTS or CSS as coagulant aid was reduced from 3100 to 2000 mg/L. In the presence of 2000 mg/L PACl with 6000 mg/L NSTS and 2000 mg/L PACl with 5000 mg/L CSS, the removal performance for color, SS, and turbidity are 94.7, 99.2, and 98.9%, respectively. Similar results were obtained with the use of 3100 mg/L PACl alone. Therefore, CSS and NSTS can be used as coagulant aid.