Separation of Emulsified Oil from Industrial Wastewater Using Poly Silicate Ferro-Aluminum Sulphate (PSFAS): A Novel Methodology for the Attainment of Very High Separation Efficiency

The large amount of wastewater generated from textile industries, petroleum industries, chemical industries contains heavy metals, suspended solids, hazardous waste, oils, fatty acids, dyes, pigment etc. It is very important to improve the quality of contaminated water before it discharges into the water sources or use. In the current work, an efficient methodology has been developed to separate emulsified oil from wastewater. The emulsified oil is tried to separate by using poly silicate Ferro aluminium sulphates, a flocculent. In addition to the above, the maximum separation efficiency for the devolved process is also revealed. Using PSFA, up to 93.5 % separation efficiency is achieved, and the discussed methodology can separate emulsified forms of the oil without altering the efficiency. The dissolved solid and metal content are also considered as the controlling parameters for the separation efficiency. The optimum TDS and the metal content must be maintained at 560 mg/L and 2 mg/L, respectively, to attain maximum separation efficiency.

Optimization of ACH Coagulant, Settling Time and Powdered Activated Carbon as Coagulant Aid with Economic Analysis

<p>Regular water treatment-plant (WTP) comprises of a number of units. Of course, problems exist throughout design and operation of the WTP units. Consequently, the current re-search aimed to minimize the shortcomings of the coagulation, sedimentation, and the adsorption methods through applying optimal process for these units. Additionally, eco-nomic analysis and the derivation mathematical models for the new coagulant (Aluminum Chlorohydrate (ACH)) and the traditional aluminum sulphate coagulant (Alum) were an-other objective of this work. Optimum coagulants for alum and ACH were obtained and presented for different raw water turbidities. The optimum settling time of 30 minutes and 40 minutes have been found for the settling of 1000 and 2000 NTU raw water sam-ples. Best dosages of 0.1 and 0.25 g/L of powdered actived carbon (PAC) were obtained for raw water turbidity of 419, and 1000 NTU which increased the removal efficiency of 28.95%, and 25.71%, respectively. Furthermore, the economic study for alum and ACH revealed that using ACH instead of alum led to reduction of cost by 32%. Commonly, it can be concluded that using ACH instead of alum is better because it is cheaper and more efficient. The predicted equations for the optimum dosages (Y) for alum (mg/L) and ACH (µl/L) dosages (X) were Y= 0.04 X + 14.42, and Y = 0.01 X + 0.72, respectively.</p>

Comparison of Alum and Sulfuric Acid to Retain and Increase the Ammonium Content of Digestate Solids during Thermal Drying

Aluminum sulphate (alum, Al2(SO4)3·nH2O) has successfully been used to reduce ammonia loss from poultry litter, cattle feedlots and manure composting, but has not yet been utilized in the thermal drying process of digestate solids. The objectives of the present study were to evaluate the effects of alum addition on ammonium nitrogen (NH4+-N) content and phosphorus (P) solubility in dried digestate solids in comparison to the addition of concentrated sulfuric acid (H2SO4). Manure-based (MDS) and sewage sludge-based (SDS) digestate solids were chosen to conduct a drying experiment at four pH levels (original pH, 8.0, 7.5 and 6.5) and using two acidifying agents (alum, concentrated H2SO4). Alum addition increased the final NH4+-N content significantly from 1.4 mg g−1 in the non-acidified control up to 18 mg g−1 and 10.8 mg g−1 in dried MDS and SDS, respectively, which were higher levels than obtained with the addition of concentrated H2SO4. Moreover, alum considerably lowered the water extractable phosphorus (WEP) in raw and dried SDS by 37–83% and 48–72%, respectively, compared with the non-treated control. In contrast, concentrated H2SO4 notably increased WEP in raw and dried MDS by 18–103% and 29–225%, respectively. The comparison between the two acidifying agents indicated that alum had the potential to be an efficient and easy-handling alternative to concentrated sulfuric acid, resulting in higher NH4+-N content and lower P solubility.

Optimizing NOM Removal: Impact of Calcium Chloride

Understanding the character of natural organic matter (NOM) and assessing its impact on water quality is paramount for managers of catchments and water utilities. For drinking-water producers, NOM affects disinfectant demand and the formation of by-products which can have adverse health effects. NOM content in raw waters also has an impact on water treatment processes by increasing required coagulant dosages, reducing the effectiveness of adsorption processes and fouling membrane systems. This study investigated the effects of calcium chloride (CaCl2) as a co-coagulant in Al3+ and Fe3+ assisted coagulation, flocculation and sedimentation processes for NOM-removal from raw water collected from Lake Bolmen, in southern Sweden. Jar tests were conducted at Ringsjö Water Works (WW), a surface water treatment plant (WTP), to investigate the potential reduction in primary coagulants aluminum sulphate (Al2(SO4)3) and ferric chloride (FeCl3). This work shows that CaCl2 can, in certain situations, reduce the need for primary coagulants, which would reduce the environmental impact and costs associated with primary coagulant consumption.

Optimal Precipitation Of Zn+₂ and Ni+₂ From Aqueous Solution: Influence Of Rapid Mixing Parameters

Wastewater containing Zn+₂and Ni+₂is normally treated by chemical precipitation, coagulation, flocculation followed by clarification.The metal precipitation is influenced by chemical (wastewater pH, coagulant type and dose) and physical (rapid mixing speed and time) parameters. The process usually consists of the rapid dispersal of a coagulant into the wastewater followed by an intense agitation commonly defined as rapid mixing. This study focused on the most important parameters of rapid mixing design: mixing intensity and duration. Simulated aqueous solutions containing 50 ppm Zn+₂and 50 ppm Ni+₂were treated with aluminum sulphate, ferrous sulphate and ferric chloride coagulants at different doses and different rapid mixing times and speeds. Experimental results obtained indicate that ferric chloride at 30 mg/l dose was superior over aluminum sulphate and ferrous sulphate at the same dose in Zn+₂and Ni+₂removals. Rapid mixing time had a strong influence on the metal removal. An optimal combination of rapid mixing parameters was determined as: 60 s at 100 rpm for Zn+₂and 30 s at 80 rpm for Ni+₂removals. Scanning electron microscopy images for Zn+₂and Ni+₂flocs at optimum parameters of rapid mixing show that ferric chloride addition compacts the surface texture of the metals flocs. Flocs formed by Zn+₂are denser and larger than flocs formed by Ni+₂.

Optimal Precipitation Of Zn+₂ and Ni+₂ From Aqueous Solution: Influence Of Rapid Mixing Parameters

Wastewater containing Zn+₂and Ni+₂is normally treated by chemical precipitation, coagulation, flocculation followed by clarification.The metal precipitation is influenced by chemical (wastewater pH, coagulant type and dose) and physical (rapid mixing speed and time) parameters. The process usually consists of the rapid dispersal of a coagulant into the wastewater followed by an intense agitation commonly defined as rapid mixing. This study focused on the most important parameters of rapid mixing design: mixing intensity and duration. Simulated aqueous solutions containing 50 ppm Zn+₂and 50 ppm Ni+₂were treated with aluminum sulphate, ferrous sulphate and ferric chloride coagulants at different doses and different rapid mixing times and speeds. Experimental results obtained indicate that ferric chloride at 30 mg/l dose was superior over aluminum sulphate and ferrous sulphate at the same dose in Zn+₂and Ni+₂removals. Rapid mixing time had a strong influence on the metal removal. An optimal combination of rapid mixing parameters was determined as: 60 s at 100 rpm for Zn+₂and 30 s at 80 rpm for Ni+₂removals. Scanning electron microscopy images for Zn+₂and Ni+₂flocs at optimum parameters of rapid mixing show that ferric chloride addition compacts the surface texture of the metals flocs. Flocs formed by Zn+₂are denser and larger than flocs formed by Ni+₂.

Effects of Flame Retardant on the Flammability of Treated and Untreated Bagasse Papers

A comparative study of the proximate analysis, fire characteristics, and mechanical properties of the papers produced from pretreated and untreated bagasse was carried out. The bagasse collected was washed, dried, depithed and ground to pass through a 5 mm sieve using an electric milling machine. A portion was pulped without pretreatment, while others were pretreated (acetylation) before pulping and washing. After which different mass (0,2,4,6,8 and 10 g) of potassium aluminum sulphate, KAl(SO4)2.12H2O (alum) as flame retardant was added. The proximate analysis, fire characteristics and mechanical properties were determined. Results show that cellulose content increased with an increase in the concentration of potassium aluminum sulphate, while hemicellulose content increased from 24%-34% for flame retarded paper with 0-10 g concentration of alum. Lignin content also increased from 21.3%-63.2% for flame retarded paper with 0-10 g concentration of alum, respectively. Ash content varied with an increase in the concentration of potassium aluminum sulphate. Results from fire characteristics show that flame propagation and flame duration rate decreased with an increase in the concentration of alum, while ignition time and char formation increased in the concentration of alum. The mechanical properties, tensile strength, modulus and elongation at break were enhanced. Conclusively, pretreatment enhanced the properties of bagasse papers produced.