When doing experiments on the preparation of inorganic coagulant polyferric sulfate and the effect of sewage treatment in the laboratory, the experimental steps after the hydrolysis of polyferric sulfate are as follows:
1. Fe2+ detection in the product polymer ferric sulfate
Take 5mL polyferric solution, add it to a 250mL Erlenmeyer flask, dilute to 100~150mL, add 10mL sulfur-phosphorus mixed acid, add 5~8 drops of sodium diphenylamine sulfonate solution after cooling, and titrate with K2Cr2O7 standard solution to a stable purple.
2. Detection of alkalinity
a. Use a pipette to take 1.00 mL of polyferric solution and place it in a 250 mL conical flask
b. Use a pipette to accurately pipette 25.00 mL of hydrochloric acid, then add 20 mL of CO2-free distilled water and shake well, cover with a watch glass, and place it at room temperature for 10 minutes.
c. Add 10mL potassium fluoride solution and shake well. Add two more drops of phenolphthalein, and immediately titrate with sodium hydroxide standard solution to light red as the end point. (Or titrate to a pH value of 9.0~9.5) d. Use distilled water without CO2 as a blank test and repeat the above steps.
How to use polyferric sulfate in production and daily life:
When in use, liquid polymeric ferric sulfate is generally formulated into a 10%-50% aqueous solution (it can be directly added when the source water has high turbidity), and solid polymeric ferric sulfate is formulated into a 10%-30% aqueous solution. According to the specific situation, put the prepared solution according to the best conditions and dosage, and the best coagulation effect can be obtained after full stirring.
The dosage can be determined according to the different turbidity of the raw water to determine the best dosage. For general turbidity (turbidity of 100-500mg/L) water, use 30-50 kg of this product per thousand tons, non-drinking water high turbidity industrial wastewater can be appropriate Dosing amount.
When treating industrial wastewater, dilute the first-class polymer ferric sulfate to 1-2 times the aqueous solution. When the source water concentration is high and the treated water volume is large, it can be directly added. Then, according to the results of the laboratory simulation test, dosing according to the best process conditions and dosage, after full stirring, coagulation and sedimentation, clear effluent can be obtained.
The water purification plant can also be added after diluting 2-5 times. The dosage is determined according to the nature of the raw water through production debugging or beaker experiment depending on the proper amount of alum formation. The water plant can use other medicine dosages as a reference. Under the same conditions, the dosage of this product and solid polyaluminum chloride It is roughly equivalent, 1/2-1/3 of the amount of solid aluminum sulfate. If the original liquid product is used, it can be determined according to the concentration of the corresponding agent, roughly according to the weight ratio of 1:3.
A lot of practice has proved that ordinary polyferric sulfate can hardly achieve the expected purpose in most cases. Under normal circumstances, it is necessary to conduct a dosage form selection test according to the medium and location of use to determine the appropriate 23 Qian SC applied science and technology dosage form and initial usage before industrialization. Dynamic test to determine the best dosing point and the best dosing place. In order to facilitate the continuous expansion of the application range of polyferric sulfate in the field of mining and metallurgy.