For the newly purchased glass filters, a preliminary filtration should be conducted using hot hydrochloric acid or chromic acid, followed by a thorough rinse with distilled water to remove any dust or impurities that may be present in the filter.
After each use or after a certain period of use, effective cleaning is required to prevent sediment from blocking the filter pores and affecting the filtration function. For the 6th disinfection filter, an immediate backflush with an effective cleaning solution should be performed after each use. Before the solution is fully filtered, remove the filter and soak it in the cleaning solution for approximately 48 hours (both sides of the filter film should be in contact with the solution), then remove it, flush with hot distilled water, and finally dry it.
The preparation of various chemical detergents can be referred to in the following table.
Sludge | Detergent |
Fat, grease | Carbon tetrachloride or other suitable organic solvents. |
White Protein Adhesive | Hydrochloric acid, hot ammonia, a 5-10% alkaline solution, or a mixture of hot sulfuric acid and nitric acid. |
Organic Matter | A warm, concentrated sulfuric acid solution mixed with chromic acid, or a solution containing a small amount of potassium nitrate and high concentration sulfuric acid, is left overnight. |
Cuprous Chloride, Iron Stain | Mixed with hot concentrated hydrochloric acid. |
Barium sulfate | 100°C concentrated sulfuric acid. |
Mercury Slag | Hot concentrated nitric acid. |
Mercuric sulfide | Hot aqua regia. |
Silver Chloride | Solution of ammonia or sodium thiosulfate. |
Aluminum and silicon slag | Following washing with concentrated sulfuric acid, rinse immediately with distilled water followed by acetone, repeating the rinse until no acid residue is visible. |
Bacteria | 5.72 mL of pure concentrated sulfuric acid, 2.00 grams of pure sodium nitrate, and 94 mL of distilled water, mixed thoroughly and evenly. |
The thickness of the glass filter is designed based on flow rate and certain mechanical strength. Therefore, when under positive or negative pressure, it is crucial to ensure that the pressure difference between the two sides of the filter does not exceed 1 cm². Additionally, due to the unique shape of the filter and the welding of the filter edge to the housing, heating or cooling must be performed slowly.
Glass filters are not suitable for filtering hot or cold concentrated phosphoric acid or concentrated alkali solutions. These reagents can dissolve the particles of the filter plate, causing the filter pores to expand or the filter plate to crack. Please note when using them.
