Effects of Silica Polymization on Apparent Viscosity of Geothermal Water - Fundamental Study on Precipitation of Silica Scale -

二氧化硅聚合对地热水表观粘度的影响 - 二氧化硅垢沉淀的基础研究 -

• 批准号: 62550456
• 负责人: CHIDA Tadashi
• 金额: $ 1.28万
• 依托单位: TOHOKU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1987
• 资助国家: 日本
• 起止时间: 1987 至 1988
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-62550456/
• 关键词: Rate of silica polymization; Apparent viscosity; Silica deposition; Precipitation of silica; Decrease of permeability; Soluble silica; Polysilicic acid; 全ケイ酸濃度; シリカ; 貯留層の透水性低下; シリカの沈澱; モリブデン黄吸光光度法; スケール付着量; 見掛け粘度; 炭素綱板; 回転粘度計

This study discussed on (1) the rate of silica polymerization, (2) the relation between the apparent viscosity and the deposition to carbon steel and (3) the decrease of permeability caused by the precipitaion of silica. The conclusions are as follow:(1) The rate of decrease in soluble silica concentration is proportional to the surface area of polysilicic acid and the twice power of the oversatulated soluble silica concentration, when the experimental conditions are under pH8-9, temperature 30-50゜C, NaCl concentration 0 mol dm^<-3>, initial soluble silica conc. about 520ppm and total silica conc. about 570ppm.(2) As the apparent viscosity of solution increases, the quantity of silica deposition to carbon steel increases. Also as the precipitation is generated, the apparent viscosity of solution increaes rapidly. Then, the experiments conditions are; ph8-9, temp. 30゜C, NaCl conc. 0-1mol dmD1-3@>D1, initial soluble 250-1500ppm.(3) The effects of silica precipitation to the decrease of permeability depend on the particle diameter, when the experiments are carried out by using packed bed with glass beads. In the case of 0.3mm diameter beads, the permeability decreases generally. On the other hand, in the use of 1mm diameter beads, recovery of the permeability after the rapid decrease.

本研究讨论了(1)二氧化硅聚合速率；(2)表观粘度与碳钢沉积的关系；(3)二氧化硅沉淀引起的渗透率降低。结果表明：(1)当实验条件为ph8 ~ 9、温度30 ~ 50 C、NaCl浓度0 mol dm^<-3>、初始可溶二氧化硅浓度时，可溶二氧化硅浓度的下降速率与聚硅酸表面积和过饱和二氧化硅浓度的两倍幂成正比。约520ppm和总二氧化硅含量。大约570 ppm。(2)随着溶液表观粘度的增加，硅石沉积到碳钢上的量也增加。同时，随着沉淀的产生，溶液的表观粘度迅速增加。然后，实验条件为；ph8-9，温度30℃，NaCl conc。0-1mol dmD1-3@>D1，初始可溶性250-1500ppm。(3)采用玻璃微珠填充床进行实验时，二氧化硅沉淀对渗透率降低的影响与粒径有关。在直径0.3mm的情况下，渗透率普遍降低。另一方面，在使用直径1mm的微球后，恢复后的渗透率迅速下降。

项目成果

今野貴洋.新掘雄一.千田佶: 日本地熱学会 昭和62年度学術講演会講演要旨集. 51 (1987)

Takahiro Konno、Yuichi Shinbori 和 Kei Senda：日本地热学会 1985 年学术会议摘要 51 (1987)。