Water Hardness Removing Chemical

I would like to know how it is possible to reduce water hardness to zero.

I got a sample from a supplier, prepared the 50% solution and added 5 ml of it to reverse osmosis (RO) with salt rejection = 1.
Initial water hardness was 700 ppm and after adding the chemical it dropped to 0 ppm.
Moreover, there was no sludge forming.

How is this possible? Has anyone ever used such an efficient chemical? 
What were the best results you have ever managed to achieve? 

Taxonomy

• Purification
• Reverse Osmosis
• Chemicals
• Inorganic Chemicals
• Water Purification
• Total Dissolved Solids (TDS)

5 Answers

1. I think there was already a formed precipitate or compound but this compound is dissolved so you can not see it. I do not know the name or if it is mineral or organic. regards

2. Hardness reducing chemicals are basically phosphates & orthophosphates. They react with Ca, Mg & silica to form a water soluble compound. Antiscalant in RO used for membrane protection. Hardness makes up to TDS, as TDS removed during RO so hardness also. For ultra pure water, Nil tds you need DM plant. But if you want cheaper method ;can use water softener,  practically u will achieve hardness 3-5 ppm.

3. you dont need to add chemical to reverse osmosis for reducing hardness reverse osmosis chemical is antiscalant and sodium meta bi sulfate for hardness you dont need to add chemicals .

   my suggestion to you is,dont add chemical which reduces hardness to RO without addition of chemical,analyse the permeate water and you will get 0 ppm of hardness.

   1 Comment

   1. RO membrane has limit for  Hardness Removal.

4. Chemicals that do not form a precipitate on removing water hardness include; brand name - Calgon (Sodium Hexametaphosphate (NaPO3)6) and tetrasodium diphosphate, Na4P2O7. As you said, there was no sludge formation (I guess you mean precipitate), you can check to confirm any of these two chemicals. I hope this terse information helps. Cheers.

    

    

   1 Comment

   1. Thank s sir,I will check as you said, and Ph of the chemical is 2.

      Am doing EDTA test for Hardness.

       

5. He gave you EDTA-Na , which is the titration substance for Hardness analysis (Titriplex). It is really make complex with calcium and magnesium, but also with all other metals which are soluble in water  and -be carefull- also unsoluble into water, which means that it is very corrosive .

   Regards !