scholarly journals Recycling of Reverse Osmosis (RO) Reject Water as a Mixing Water of Calcium Sulfoaluminate (CSA) Cement for Brick Production

2019 ◽  
Vol 9 (23) ◽  
pp. 5044
Author(s):  
Hwan Lee ◽  
Dongho Jeon ◽  
Haemin Song ◽  
Sung Won Sim ◽  
Dohoon Kim ◽  
...  
Keyword(s):  
Reverse Osmosis ◽  
Toxicity Characteristic Leaching Procedure ◽  
Cement Pastes ◽  
Calcium Sulfoaluminate ◽  
Reject Water ◽  
Ettringite Formation ◽  
Friedel’S Salt ◽  
Mixing Water ◽  
Strength Improvement ◽  
Leaching Procedure

This study explored the possibility of using reverse osmosis (RO) reject water as a mixing water for producing cementitious bricks using calcium sulfoaluminate (CSA) cement along with gypsum, and it investigated the changes in the properties of CSA cement pastes when RO reject water was used. The results were compared with those obtained using purified water and seawater. Overall, the use of RO reject water improved the cement paste’s strength. Given that the use of RO reject water very slightly affected ettringite formation but more significantly influenced the Al2O3-Fe2O3-mono (AFm) phases (i.e., monosulfate, kuzelite, and Friedel’s salt) and amorphous aluminum hydroxide (AH3), the strength improvement was likely mainly due to the formation of Friedel’s salt rather than ettringite formation. This study also demonstrated that the use of RO reject water for brick production satisfied the Korean Standards (KS) F 4004 and toxicity characteristic leaching procedure (TCLP); thus, it is recommended to use RO reject water as a mixing water to produce CSA cement bricks for use in construction.

scholarly journals Effects of Particle Size and Contact Time on the Reliability of Toxicity Characteristic Leaching Procedure for Solidified/Stabilized Waste

1998 ◽  
Vol 59 (2) ◽  
pp. 326-332 ◽  
Author(s):  
Michael A. Janusa ◽  
Jeffrey C. Bourgeois ◽  
Grant E. Heard ◽  
Nicole M. Kliebert ◽  
April A. Landry
Keyword(s):  
Particle Size ◽  
Contact Time ◽  
Toxicity Characteristic Leaching Procedure ◽  
Leaching Procedure

Collaborative Study of the Toxicity Characteristic Leaching Procedure (TCLP)

2009 ◽  
pp. 14-14-48 ◽  
Author(s):  
WB Blackburn ◽  
I Show ◽  
L Williams ◽  
DR Taylor ◽  
PJ Marsden
Keyword(s):  
Collaborative Study ◽  
Toxicity Characteristic Leaching Procedure ◽  
Leaching Procedure

scholarly journals Benchmarking of scaling and fouling of reverse osmosis membranes in a power generation plant of paper and board mill: an industrial case of a paper and board mill study

2020 ◽  
Author(s):  
S. Z. J. Zaidi ◽  
A. Shafeeq ◽  
M. Sajjad ◽  
S. Hassan ◽  
M. S. Aslam ◽  
...  
Keyword(s):  
Reverse Osmosis ◽  
Acid Treatment ◽  
Power Plants ◽  
Saturation Index ◽  
Thermal Power ◽  
Treatment Plant ◽  
Feed Water ◽  
Operational Parameters ◽  
Water Stream ◽  
Reject Water

AbstractThe present study reports the characterization of reverse osmosis (RO) technology at water treatment plant Cogen-2 in paper and Board mills, Pakistan. RO is a commonly used process to obtain de-mineralized water for high-pressure boiler operation in thermal power plants. Scaling and fouling in three-stage RO plants is a major challenge in chemical industry due to the use of raw brackish water in the power plant of paper and board mills. In our study, the feed water quality of RO was changed from soft water to raw water to make it economical. The cleaning frequency was increased three times than normal, which was unsafe for operation and it was required to control scaling and fouling to achieve the desired result. Differential pressures behavior of all stages for 2-month data was observed without acid treatment, and the results of Langelier Saturation Index (LSI) control parameters (temperature, pH, total dissolved solids, calcium hardness, and alkalinity) clearly showed the abnormality. To optimize scaling and fouling of RO, the LSI factor was controlled in total reject water for the next 2 months by acid treatment in feed water. Duration of chemical cleaning and membranes’ life has been extended by fouling and scaling control. Understanding the effect of operational parameters in RO membranes is essential in water process engineering due to its broad applications in drinking water, sanitation, seawater, desalination process, wastewater treatment, and boiler feed water operation. The product flow increased from 18.3 to 19.9 m3/h, and this was due to a decrease in the rejection flow from 8.2 to 6.7 m3/h. The total reject stream pressure also increased from 8.1 to 9 bar. A lower value of LSI of 1.6 is obtained in the reject water stream after the acid treatment.

Delayed ettringite formation in 4-year old cement pastes

1996 ◽  
Vol 26 (11) ◽  
pp. 1649-1659 ◽  
Author(s):  
R. Yang ◽  
C.D. Lawrence ◽  
J.H. Sharp
Keyword(s):  
Delayed Ettringite Formation ◽  
Cement Pastes ◽  
Ettringite Formation

Assessment of toxicity of heavy metal contaminated soils by the toxicity characteristic leaching procedure

2006 ◽  
Vol 28 (1-2) ◽  
pp. 73-78 ◽  
Author(s):  
Yefang Sun ◽  
Zhengmiao Xie ◽  
Jing Li ◽  
Jianming Xu ◽  
Zuliang Chen ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Contaminated Soils ◽  
Toxicity Characteristic Leaching Procedure ◽  
Leaching Procedure

Immobilization of ASH by Microwave Melting

1992 ◽  
Vol 269 ◽  
Author(s):  
Kazuki Morita ◽  
Vinh Q. Nguyen ◽  
Ron Nakaoka ◽  
John D. Mackenzie
Keyword(s):  
Electron Microscopy ◽  
Lithium Carbonate ◽  
Microwave Oven ◽  
Toxicity Characteristic Leaching Procedure ◽  
Leaching Rate ◽  
X Ray Diffraction ◽  
X Ray ◽  
Leaching Procedure ◽  
Pb Immobilization ◽  
Scanning Electron

ABSTRACTNon-radioactive ash was immobilized via microwave melting. The ash composed mainly of silica (SiO2), titania (TiO2), calcia (CaO), alumina (Al2O3), and carbon (C). The ash was melted with various additives, such as magnetite (Fe3O4), lithium carbonate (Li2CO3), sodium carbonate (Na2CO3), and boron oxide (B2O3) by using a 2.45 GHz, 750 W microwave oven. Samples with different ash and additive concentrations were melted when subjected to microwave radiation. Ease of melting was dependent on the carbon and magnetite concentrations. Melted samples were characterized by X-ray diffraction and scanning electron microscopy (SEM), and subjected to the Toxicity Characteristic Leaching Procedure in regard to lead (Pb) immobilization. Melted samples with more than 30 wt% additives has an undetectable leaching rate of less than 0.1 ppm of lead for TCLP test, which was found to be due to the reduction and evaporation of the lead during melting. More than 80 % of the lead was lost through evaporation leaving less than 0.1 wt% Pb in the melted glass.

Sign in / Sign up

Export Citation Format

Share Document