Dear Haiyou, please help calculate the amount of caustic soda required to adjust the pH of the sewage tank! !
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Dear Haiyou, please help calculate the amount of caustic soda needed to adjust the pH of the sewage tank! ! The volume of wastewater in the sewage tank is approximately 460 M3, with a pH of around 3. How many kilograms of caustic soda are needed to adjust it to around 7?
At a water temperature of 25°C, with a caustic soda purity of 100% and other interfering factors ignored: (1/1000)*460*1000*（40/1000）=18.4 kg.
At 25°C, ignoring the influence of other factors and assuming a purity of 95% for the caustic soda: 0.001*460*40/95% = 19.37 kilograms
This post was last edited by zhaolijun on 2015-8-14 at 11:43. PH=3 means that the concentration of H(+) is 10^(-3), and the molar concentration is 1/1000 = 0.001 mol/L. To achieve complete neutralization, an equal amount of OH(-) is required, as well as an equal amount of sodium hydroxide (with a molar mass of 40 g/mol). The amount needed is therefore 0.001 mol/L * 460 tons * 40 g/mol; dividing this by the concentration of caustic soda gives (1/1000) * (460*1000) * (40/1000) / 95% = 19.37 kilograms
I added 25KG of caustic soda, but it doesn’t seem to be working?
I added 25KG of caustic soda, but the effect wasn’t very good.
1. Check whether the mixture is homogeneous, and determine the purity of the caustic soda； 2. Caustic soda needs to be dissolved before addition; a lower concentration facilitates better mixing ； 3. Are there pH buffering substances such as phosphates in the water? If so, they will have an impact on neutralization.
Gorou’s Bagua Stick, hello! Today I added 75KG of NaOH to the accident emergency pool. The purity is 99% in all cases. The volume of the water body is: 20*10*2.5 meters. The pH level, as measured with a pH test strip, is 4. There is no mixing or any other form of agitation; only a water pump is used for self-circulation. I don’t even know now whether to invest again or not. The leader wants to add it; I’m afraid it will turn alkaline. That’s just causing trouble for myself. Calculated as follows: (1/1000) mol/l * (500*1000) l * 40 g/mol = 2000 g = 2 Kg. Should we throw it again? Thank you!
Take a sample of water, add caustic soda to it in the appropriate proportion and stir; by measuring the pH value, you can determine whether the amount added is suitable.
1. It is best to conduct pilot tests, as this provides relatively higher accuracy. 2. What is the flow rate of the pump used for circulation? Determine the cycle period. Check the pH after every other cycle. 3. What is the area of the sewage tank? If it’s quite large, it’s best to add another pump cycle.
I’m referring to the area of the sewage tank, not its volume. . . .