THE DESIGN AND ANALYSIS OF EXPERIMENTS. By Oscar Kempthorne. New York, John Wiley and Sons, Inc., 1952. 631 pp. $8.50. This book by a teacher of statistics (as well as a consultant for \"experimenters\") is a comprehensive study of the philosophical background for the statistical design of experiment. It is necessary to have some facility with algebraic notation and manipulation to be able to use the volume intelligently. The problems are presented from the theoretical point of view, without such practical examples as would be helpful for those not acquainted with mathematics. The mathematical justification for the techniques is given. As a somewhat advanced treatment of the design and analysis of experiments, this volume will be interesting and helpful for many who approach statistics theoretically as well as practically. With emphasis on the \"why,\" and with description given broadly, the author relates the subject matter to the general theory of statistics and to the general problem of experimental inference. MARGARET J. ROBERTSON

The Design and Analysis of Experiments

Application of low-cost adsorbents for dye removal – A review

https://cyberleninka.org/article/n/999493.pdf

New trends in removing heavy metals from industrial wastewater

Activation of persulfate (PS) and peroxymonosulfate (PMS) and application for the degradation of emerging contaminants

Landfill leachate treatment: Review and opportunity

The landfill leachate was taken from the Pulau Burung Landfill Site (PBLS), Malaysia. Filtration by limestone-zeolite (15 : 25) and limestone-GAC (15 : 25) with filtration rate = 0.01 m3/m2.minute showed that 70% and 85% of colour and 42% and 70% COD were removed, respectively. Maximum colour removal (93% and 92%) and COD removal (56% and 46%) were achieved by the addition of 2000 mg/L PAC and 9000 mg/L alum respectively. Filtration by limestone-zeolite (15 : 25) and limestone-GAC (15 : 25) followed by coagulation at optimum dosage of 800 mg/L PAC, was efficient to reduce colour (98% and 99%) and COD (70% and 86%) respectively.

Application of combined filtration and coagulation for semi-aerobic leachate treatment

This study examines the suitability of natural silica sand as a low-cost adsorbent for the removal of ammoniacal nitrogen and heavy metals, particularly iron and zinc, from semi-aerobic stabilized landfill leachate. Leachate samples were collected from the Pulau Burung landfill site (PBLS) in Penang, Malaysia. The above-mentioned contaminants are highlighted in this study because of their unsafe concentrations at PBLS. The effects of shaking time, settling time, and silica sand dosage on the study parameter removal efficiencies were investigated to predict the performance of the process. The adsorptions of ammoniacal nitrogen, iron, and zinc were judiciously described by Langmuir and Freundlich isotherm models. The optimum removal efficiencies of ammoniacal nitrogen, iron, and zinc obtained were 51%, 44.4%, and 39.2%, respectively, with a shaking time of 90 min, a settling time of 60 min, and with a dosage of 60 g (0.5 kg/L) of silica sand. Based on the coefficient of determination (R2) values obtained from Langmuir and Freundlich isotherm models, ammoniacal nitrogen, iron, and zinc adsorption were better fitted to the Freundlich model.

https://engagedscholarship.csuohio.edu/cgi/viewcontent.cgi?article=1386&context=encee_facpub

The Effectiveness of Silica Sand in Semi-Aerobic Stabilized Landfill Leachate Treatment

In this research, two types of sequencing batch reactors (SBRs) with 8 h of cycle times, namely non-powdered activated carbon (NPAC-SBR) and powdered activated carbon (PAC-SBR), were used for the treatment of raw leachates at Kulim and Pulau Burung landfill sites. To test the performance of SBRs, phenols, total iron, zinc, ammonia, nitrite, nitrate, color, suspended solids, chemical oxygen demand, biochemical oxygen demand, and total dissolved salts removal efficiencies and sludge volume index (SVI) were studied at both sites. The rates of phenols removal, for instance in NPAC-SBRs and PAC-SBRs at Kulim, were 25% and 55%, respectively, whereas those at Pulau Buring were 94.81% and 97.75%, respectively. PAC as adsorbent in PAC-SBRs enhanced the removal efficiencies of the aforementioned pollutants from leachates at both sites. In addition, PAC as adsorbent decreased the SVI values at Kulim (59.7 mL/g) and Pulau Burung (91.4 mL/g) leachates and improved the nitrification and denitrification processes.

Removal of phenols and other pollutants from different landfill leachates using powdered activated carbon supplemented SBR technology

In this research, the bioremediation of dispersed crude oil, based on the amount of nitrogen and phosphorus supplementation in the closed system, was optimized by the application of response surface methodology and central composite design. Correlation analysis of the mathematical-regression model demonstrated that a quadratic polynomial model could be used to optimize the hydrocarbon bioremediation (R 2 = 0.9256). Statistical significance was checked by analysis of variance and residual analysis. Natural attenuation was removed by 22.1% of crude oil in 28 days. The highest removal on un-optimized condition of 68.1 % were observed by using nitrogen of 20.00 mg/L and phosphorus of 2.00 mg/L in 28 days while optimization process exhibited a crude oil removal of 69.5% via nitrogen of 16.05 mg/L and phosphorus 1.34 mg/L in 27 days therefore optimization can improve biodegradation in shorter time with less nutrient consumption.

Response Surface Analysis to Improve Dispersed Crude Oil Biodegradation

A study was conducted to determine the removal efficiency of heavy metals (Ni, Cd, Pb and Zn) and colour from wastewater using cheap available materials in Malaysia such as charcoal, coconut shell carbon and a mixture of these carbons with limestone. As activated carbon is quite expensive, this study attempts to investigate the possibility of mixing activated carbon with these materials for cost saving. The suitability of using coconut shell after heating at 500°C in treating wastewater also formed the basis of the study. Batch studies were carried out in the laboratory with an initial concentration of heavy metals generally found in final effluents at 2 mg/L and colour at 400-ptCo. The results indicated that a mixture of activated carbon and limestone had removed 92% of heavy metals and 85% of colour from synthetic wastewater at a wide range of pH. When activated carbon was only used, 85% of heavy metals and 99% of colour were removed. For a mixture of charcoal with limestone, the removal efficiencies for heavy metals and colour were at 65% and 35%, respectively. The removal efficiency for heavy metals was further improved to 80% when charcoal was used, but for colour removal it was only 30%. The results of the study suggested that a mixture of activated carbon with limestone had significantly removed the amount of heavy metals and colour. Thus, the cost of the overall process can be reduced. This study also indicated that there is possibility of using coconut carbon and charcoal as an alternative absorbents for removing heavy metals and colour from wastewater. However, improvement on activation process is required.

/pdf/removal-of-ni-cd-pb-zn-and-colour-from-aqueous-solution-5b0h5x7lv5.pdf

Hamidi Abdul Aziz

Papers

Application of combined filtration and coagulation for semi-aerobic leachate treatment

The Effectiveness of Silica Sand in Semi-Aerobic Stabilized Landfill Leachate Treatment

Removal of phenols and other pollutants from different landfill leachates using powdered activated carbon supplemented SBR technology

Response Surface Analysis to Improve Dispersed Crude Oil Biodegradation

Removal of Ni, Cd, Pb, Zn and colour from aqueous solution using potential low cost adsorbent