硅酸鈉是無機硅化合物行業(yè)中產(chǎn)量大的基礎(chǔ)原料,廣泛地應(yīng)用于化學(xué)、造紙、焊接、洗滌日化、鑄造、冶金、催化、涂料、包裝等行業(yè)。由于硅酸鈉本身具有一定的堿性,同時其水溶液有緩沖pH值作用,而且水解產(chǎn)生的膠束結(jié)構(gòu)的硅酸具有分散、乳化、懸浮油墨以及鈍化金屬離子的作用,因此硅酸鈉在造紙廢紙脫墨及常規(guī)過氧化氫漂白中有著廣泛的應(yīng)用。
Sodium silicate is a high-yield basic raw material in the inorganic silicon compound industry, widely used in industries such as chemistry, papermaking, welding, washing, daily chemical, casting, metallurgy, catalysis, coatings, packaging, etc. Due to the alkalinity of sodium silicate itself, as well as the buffering effect of its aqueous solution on pH value, and the micelle structure of silicic acid produced by hydrolysis, which has the functions of dispersing, emulsifying, suspending ink, and passivating metal ions, sodium silicate has a wide range of applications in deinking paper waste and conventional hydrogen peroxide bleaching.
但是直接應(yīng)用于造紙中的硅酸鈉也有不足之處,在脫墨與過氧化氫漂白應(yīng)用中會在設(shè)備和管道內(nèi)形成硅垢,對漿料流送產(chǎn)生阻礙,縮短停機清洗及更換設(shè)備部件的周期,降低生產(chǎn)效率。
However, sodium silicate, which is directly used in papermaking, also has shortcomings. In deinking and hydrogen peroxide bleaching applications, silicon scale can form in equipment and pipelines, hindering the flow of slurry, shortening the cycle of shutdown cleaning and replacing equipment components, and reducing production efficiency.
硅酸鈉在堿性條件下是相對穩(wěn)定的,隨著在脫墨或漂白應(yīng)用過程中的pH值的降低,硅酸鈉逐漸失去穩(wěn)定性,與漿液中的鈣離子等結(jié)合成硅酸鹽沉淀粘附到金屬表面,形成垢層。
Sodium silicate is relatively stable under alkaline conditions. As the pH value decreases during deinking or bleaching applications, sodium silicate gradually loses its stability and combines with calcium ions in the slurry to form silicate precipitates that adhere to the metal surface, forming a scale layer.
在過氧化氫漂白中添加硫酸鎂或?qū)⒘蛩徭V和過氧化氫與硅酸鈉、氫氧化鈉分前后順序加入,可防止結(jié)垢的發(fā)生。
Adding magnesium sulfate or sequentially adding magnesium sulfate and hydrogen peroxide with sodium silicate and sodium hydroxide in hydrogen peroxide bleaching can prevent scaling.
當(dāng)鈣離子與鎂離子同時存在時,硅酸鈉優(yōu)先與鎂離子反應(yīng)生成硅酸鎂沉淀,這種沉淀物是軟性的,滑石狀,并不粘附于不銹鋼表面,但是硅酸鈣沉淀卻會在金屬表面形成垢層。
When calcium ions and magnesium ions coexist, sodium silicate preferentially reacts with magnesium ions to form magnesium silicate precipitates. This precipitate is soft, talc like, and does not adhere to the surface of stainless steel. However, calcium silicate precipitates form a scale layer on the metal surface.
另外,通過加入氫氧化鈉來降低硅酸鈉的模數(shù),在廢紙脫墨中同樣也起到控制結(jié)垢的目的。
In addition, reducing the modulus of sodium silicate by adding sodium hydroxide can also control scaling in waste paper deinking.
The above is the problem of sodium silicate in papermaking application introduced by Chengzhi Industry. We hope to provide you with good help. If you have any doubts or needs, please feel free to come to the website at any time http://qxu1539600089.my3w.com Consult us!