Silica Scale Prevention for Advanced Energy Utilization of Geothermal Brine

地热卤水先进能源利用的硅垢预防

• 批准号: 09650824
• 负责人: NAKAMURA Masaaki
• 金额: $ 2.05万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09650824/
• 关键词: Geothermal Brine; Silica Scale; Silica Removal; Seeding Method; Silica Gel Seed; シリカモノマー; シード添加; シリカポリマー

We have proposed a seeding method using silica gel to remove silica from geothermal brines and applied to prevent silica scale on the heat exchanging surfaces.(1)The effects of the seed particle diameter, initial specific surface area and initial pore diameter on silica removal are experimentally examined using a model geothermal brine. The effects of the particle diameter on the quantity of the final precipitated silica and on the final specific surface area are hardly seen. The quantity of precipitated silica per unit surface area increases with increasing initial pore diameter, and the silica precipitation rate coefficient increases with decreasing particle diameter and with increasing initial pore diameter.(2)The effects of pH and some operational conditions on the silica removal performance are investigated. When the initial silica concentration is 0.5 kg-SiO2-m^<-3>, the silica removal ratio increases with increasing initial pH in the range of 5-9. When the initial pH is the same, the silica removal ratio increases with increasing temperature and with decreasing initial silica concentration. While the silica removal ratio is not affected by the pre-seeding time in the case of lower initial silica concentrations, it increases with decreasing pre-seeding time in the case of higher initial silica concentrations.(3)Model geothermal brines based on a component of dissolved salts in the actual geothermal brines were used, and the effect of dissolved salts on the silica removal performance by a seeding method using silica gel is examined. Potassium and sodium ions increase the silica supersaturation degree by their salt-out effects, and as a result promote silica removal. Calcium and ferric ions promote silica removal by production of their silicates in addition to the salt-out effect. Boric acid has little effect on silica removal.

我们提出了一种用硅胶去除地热盐水中的二氧化硅的方法，并应用于防止换热表面的二氧化硅结垢。(1)利用模拟地热盐水实验考察了种子粒径、初始比表面积和初始孔径对二氧化硅去除的影响。颗粒直径对最终沉淀二氧化硅的数量和最终比表面积的影响几乎不可见。单位表面积二氧化硅析出量随初始孔径的增大而增大，二氧化硅析出率系数随粒径的减小和初始孔径的增大而增大。(2)考察了pH和一些操作条件对二氧化硅去除性能的影响。当初始二氧化硅浓度为0.5 kg-SiO2-m^<-3>时，二氧化硅去除率在5 ~ 9范围内随初始pH的增大而增大。初始pH相同时，二氧化硅去除率随温度的升高和初始二氧化硅浓度的降低而增加。在初始二氧化硅浓度较低的情况下，二氧化硅去除率不受预播时间的影响，而在初始二氧化硅浓度较高的情况下，二氧化硅去除率随预播时间的减少而增加。(3)采用基于实际地热盐水中溶解盐组分的模拟地热盐水，考察了溶解盐对硅胶播种法去除二氧化硅性能的影响。钾离子和钠离子通过盐析作用增加二氧化硅过饱和度，从而促进二氧化硅的脱除。除盐出效应外，钙和铁离子还通过生成硅酸盐来促进二氧化硅的去除。硼酸对二氧化硅的去除效果不大。

项目成果

Hajime Sugita: "Effect of Aluminum Ion On Silica Removal from Geothermal Brine by Seeding Method Using Silica Gel" Journal of Chemical Engineering,Japan. 31(3). 462-464 (1998)

Hajime Sugita：“铝离子对使用硅胶播种法从地热盐水中去除二氧化硅的影响”化学工程杂志，日本。

H.SUGITA,Y.BANDO and M.NAKAMURA: "Effects of pH Operatinal Conditions on Silica Removal from Geothermal Brine by Seeding Method Using Silica Gel (in Japanese)" Kagakukogaku Ronbunshu. Vol.24, No.4. 552-557 (1998)

H.SUGITA、Y.BANDO 和 M.NAKAMURA：“pH 操作条件对使用硅胶播种法从地热盐水中去除二氧化硅的影响（日语）” Kagakukogaku Ronbunshu。

H.SUGITA,S.SAKURAI,Y.BANDO and M.NAKAMURA: "The Effect of Characteristics of a Seed on Silica Removal from a Model Geothermal Brine by a Seeding Method Using Silica Gel (in Japanese)" J.Soc.Powder Technol., Japan. Vol.35, No.5. 338-345 (1998)

H.SUGITA、S.SAKURAI、Y.BANDO 和 M.NAKAMURA：“种子特性对通过使用硅胶的播种方法从模型地热盐水中去除二氧化硅的影响（日语）”J.Soc.Powder Technol

杉田 創: "シリカゲルシード添加法による地熱水からのシリカ除去に及ぼす溶存塩の影響" 化学工学論文集. 24(6). 969-971 (1998)

Hajime Sugita：“通过硅胶种子添加方法溶解盐对地热水去除二氧化硅的影响”化学工程杂志 24(6) 969-971 (1998)。

H.SUGITA,Y.BANDO and M.NAKAMURA: "Removal of Silica from Geothermal Brine by Seeding Method Using Silica Gel" J.Chemical Eng., Japan. Vol.31, No.1. 150-152 (1998)

H.SUGITA、Y.BANDO 和 M.NAKAMURA：“使用硅胶播种法从地热盐水中去除二氧化硅”J.Chemical Eng.，日本。