[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

Arsenic removal from water/wastewater using adsorbents—A critical review

Physico-chemical treatment techniques for wastewater laden with heavy metals

https://cyberleninka.org/article/n/638974.pdf

Characteristics and adsorption capacities of low-cost sorbents for wastewater treatment: A review

by J. Biggs and C. Tang, Maidenhead, England,
Open University Press, 2007, 360 pp., £29.99, ISBN-13: 978-0-335-22126-4

Teaching for quality learning at university

Breakthrough curves for the removal of Ni(II), Zn(II), and Pb(II) from aqueous solutions using cation exchange resin (Dowex 50W) were determined at dynamic conditions in a fixed-bed column under ambient temperature. The experiments and data obtained were designed and analyzed using response surface methodology, respectively. Three operating parameters: flow rate (15–25 mL min−1), pH (3–9), and bed height (3–5 cm) were investigated. Fixed-bed adsorption models namely Thomas model and Bohart–Adam model were adopted to describe the dynamics of metal adsorption in the column. The obtained experimental data were fitted to these models based on the kinetic constant kBA (mg min cm−3), kTH (cm3 mg−1 min), the maximum amount of metal exchange N0 (mg cm−3), and the maximum adsorption capacities qtm (mg), accordingly. The Thomas model was found to best fit all the experimental conditions studied with correlation coefficients of 0.91, 0.97, and 0.92 for Ni(II), Zn(II), and Pb(II), respectively.

Removal of Ni(II), Zn(II) and Pb(II) from aqueous solutions using cation-exchange resin in fixed-bed column

This study presents treatment performance of cafeteria waste and polyhydroxyalkanoate (PHA) production in two stage process through an up-flow anaerobic sludge bed (UASB) and sequencing batch reactor (SBR). COD removal efficiency was found as follows: SBR, 93; and UASB - SBR, 95.4%. In addition, 30% ammoniacal nitrogen (AN) was noted at high aerobic condition and phosphate (PO 4) removal efficiency increased at high anoxic conditions. Volatile fatty acid (VFA) intermediates such as acetic acid increased from 505 up to 4315 mg.l-1 in effluent of UASB reactor and successfully consumed in SBR for PHA production. Acetic acid concentration was reduced significantly in SBR from 4315 to 50 mg.l -1. During this period, PHA production was increased to 68% over cell dried weight, confirming effectiveness of sequential UASB-SBR system in producing bioplastic from cafeteria waste.

/pdf/raw-material-resource-for-biodegradable-plastic-production-2zgf8drp4q.pdf

Raw material resource for biodegradable plastic production from cafeteria wastes

Nowadays, the volume of sewage sludge is increasing parallel with the increases in population of Malaysia. The cost to treat the sludge is very high and longer time is needed for the treatment. One of the methods that is generally use in Malaysia to treat the sludge is composting but unfortunately this method takes longer duration for the sludge to be treated for used as soil conditioner. Thus, soil amendment is introduced to improve the existing method. Sludge as soil amendment seems to become the ultimate solution for sludge management. This study was conducted to assess the suitability of sewage sludge as soil amendment for plant. Three samples have been prepared for each ratio of dried leaves and lime powder: dried sludge. Proportions of sewage sludge to the dried leaves as used in study are 1:2, 1:3 and 1:4. The results indicated the decreased in heavy metals in the sludge. The additional material for soil amendment is dried leaves and the best mixing proportion is 1:4.

Potential of sewage sludge as soil amendment

With the increasing environmental pressure to replace conventional plastics with biodegradable polymers, the reduction of production costs of the latter materials became critical [1]. Polyhydroxyalkanoates (PHAs) are considered to be good candidates for biodegradable plastics due to their large range application and capability of being produced from renewable resources [2-4]. These materials have attracted interest because of their potential use as biodegradable alternatives to petroleum-based synthetic plastics such as polypropylene and polyethylene [5]. However, the production cost of PHAs has limited their use in wide range applications [6]. Efforts have been made to produce PHAs by microbial fermentation organic waste (kitchen waste, olive oil and POME). The production of biodegradable polymers from oil palm industry can be seen as beneficial to the environment as well as contributing to sustainable development. Until recently, the remaining 90% (empty fruit bunches, fibers, fronds, trunks, kernels, POME) was discharge as waste, and either burned in the open air or left settle in waste ponds. By utilizing the POME and empty palm oil fiber bunch (EPFB) as carbon source and support matrix, the disposal of POME that needed further treatment could be reduced. In addition, the production of biodegradable polymers from POME can provide multiple benefits to the environment, and contribute to sustainable development [7,8].

Zaini Ujang

Papers

Removal of Ni(II), Zn(II) and Pb(II) from aqueous solutions using cation-exchange resin in fixed-bed column

Raw material resource for biodegradable plastic production from cafeteria wastes

Potential of sewage sludge as soil amendment

Polyhydroxyalkanoates (PHAs) production from complex polymer organic waste using anaerobic and aerobic sequence batch reactor

Performance of aerobic granular sludge at variable circulation rate in anaerobic-aerobic conditions.