As to assess the geothermal potential of a hydrothermal system, geo-chemical thermometers are well established. Among the various geochemical thermometers, the silica thermometer is very sensitive and widely used for determining the reservoir temperature of the geothermal system. The main input is dissolved silica in hot spring/ bore well waters. The quantity of the silica may vary from traces to hundred mg/lit.
In view of the importance of SiO2 in water samples, it is needed to discuss techniques for its determination.
Thanks Ashwani for your prompt response. This is very traditional method. I am interested for high concentration in hundreds mg/lit of Silica.
My Dear Virendra Kumar Saxena ji; Here are few links which may be helpful o you. Thanks
http://pubs.acs.org/doi/abs/10.1021/ac60323a021
http://pubs.acs.org/doi/abs/10.1021/j150516a002
http://www.sciencedirect.com/science/article/pii/0016703780902203
Sawan appreciate your reply. As mentioned the site has problem. However silica waterreaction can not work in the present context. In present case water is hot from 40 to 98 degree centrigate.And concentration of silica is even more than 300mg/l.
Thanks Ghanashyam, for suggesting a method ( ICP-OES ) for the estimation of dissolved Silica ( SiO2 ). In this connection, I would like to mention here that, silica in water has come from from various sources mainly either crystalline ( Quartz) or Amorphous ( chalcedony ). In particular Quartz case and also in high temperature reservoir system, silica usually formed in colloidal and also faces accuracy problem.In normal ground water, and in low concentration moll dictate silicate and ICP-OES may be effective but for low concentration.
Ghanashyam, I agree with you. But for accuracy point of view it is not advisable to do dilution or filtration.
1. Fournier,R.O and Rawe, J.J 1966 Estimation of underground temperature from silica constituents of water from hot spring and wells, Am. J. of Sciences, 264, 785.
2. Kennedy, G.C.,1950, A proportion of the system silica in water. Economic Geology, 45, 629.
silica in water samples is determined by VISIBLE spectrophotometric method
sir, i request you to please refer METHODS OF SEA WATER ANALYSIS by KLAUS GRASSHOFF ..... VERLAG CHEMIE WEINHEIM NEW YORK 1976
page number: 149-152
How about using simple Hach determination. See method 8185 and 8186. In case of very high concentrations you may use dilution usuallly Hach Method 8185 is pretty good for 0 - 75 mg/L.
hello Mr. Virendra Kumar Saxena, I am student in master 2 and looking for how silica can be estimated in water I found this forum. In fact I have no answer to you but a question, and I hope you could help me. I am analyzing river, spring and drain water samples, before the analysis I am freezing the samples, and to avoid precipitation I add HClO4. my question is if this is a good way to prepare the sample to analyze silica? I hope you can help me!
best regards from Paris.
Stefan, appreciate your remark and in interest in this subject. As Silica geothermometer is one of the best tool for evaluating the geothermal reservoir potential. During our study we determined SiO2 in large number of water samples by Molybdate blue method and By AAS
Silica analysis is important for the evaluation of Geothermal potential in high heat flow zone for power generation. Present methods are time consuming and give chances of error if storages for long time.
Dear Kumar,
I really appreciate for such an important question. I found really good comments in the responses.
Cheers,
Rahim