Water purification flocculating agent prepared from urea, and preparation method thereof

[0017] Example 1

[0018] In the embodiment of the present invention, a water purification flocculant prepared by using urea is weighed 4 kg of urea, 50 kg of polyaluminum ferric chloride, 15 kg of silica, 36 kg of lignin, 25 kg of sodium hydroxide solution, and 11 kg of alum.

[0019] The preparation method of the composite water purification flocculant prepared by using urea, the specific steps include:

[0020] 1) Dissolve urea and alum in water to prepare solution A for later use. The amount of water added is 1 time the total mass of urea and alum;

[0021] 2) Add polyaluminum ferric chloride to the sodium hydroxide aqueous solution at room temperature and stir for 10 minutes to obtain B solution;

[0022] 3) Heat solution B to 75°C, add lignin at this temperature, stir for 30 minutes, add silica, and continue stirring for 15 minutes to obtain solution C;

[0023] 4) Pour solution A into solution C, lower the temperature to 55°C, stir for 1 hour and then cool to room temperature to obta

[0024] Example 2

[0025] In the embodiment of the present invention, a water purification flocculant prepared with urea is weighed: 7 kg of urea, 56 kg of polyaluminum ferric chloride, 18 kg of silica, 42 kg of lignin, 32 kg of sodium hydroxide aqueous solution, and 14 kg of alum.

[0026] The preparation method of the composite water purification flocculant prepared by using urea, the specific steps include:

[0027] 1) Dissolve urea and alum in water to prepare A solution for later use. The amount of water added is twice the total mass of urea and alum;

[0028] 2) Add polyaluminum ferric chloride to the aqueous sodium hydroxide solution at room temperature and stir for 15 minutes to obtain B solution;

[0029] 3) Heat solution B to 78°C, add lignin at this temperature, stir for 40 minutes, add silica, and continue stirring for 15 minutes to obtain solution C;

[0030] 4) Pour solution A into solution C, lower the temperature to 55°C, stir for 1 hour and then cool to room temperature to

[0031] Example 3

[0032] In the embodiment of the present invention, a water purification flocculant prepared by using urea is weighed separately: 10 kg of urea, 63 kg of polyaluminum ferric chloride, 22 kg of silica, 47 kg of lignin, 38 kg of sodium hydroxide solution, and 18 kg of alum.

[0033] The preparation method of the composite water purification flocculant prepared by using urea, the specific steps include:

[0034] 1) Dissolve urea and alum in water to prepare A solution for later use. The amount of water added is 3 times the total mass of urea and alum;

[0035] 2) Add polyaluminum ferric chloride to the sodium hydroxide aqueous solution at room temperature and stir for 20 min to obtain B solution;

[0036] 3) Heat solution B to 80°C, add lignin at this temperature, stir for 50 minutes, add silica, and continue stirring for 15 minutes to obtain solution C;

[0037] 4) Pour solution A into solution C, lower the temperature to 55°C, stir for 1 hour and then cool to room temperatu