Calculate the amount of lime and soda required for the softening of 10^(6) L of a sample of boiler feed water with the following data: CaCO_3=1.4^@ Clark, MgCO_3=0.56^@ Clark, CaSO_4=0.42^@ Clark, MgSO_4=0.14^@ Clark, MgCl_2=0.035^@ Clark, and NaCl=0.035^@ Clark.

Calculate the amount of lime and soda required for the softening of 10

1.	Calculate the amount of lime and soda required for the softening of 10^(6) L of a sample of boiler feed water with the following data: CaCO_3=1.4^@ Clark, MgCO_3=0.56^@ Clark, CaSO_4=0.42^@ Clark, MgSO_4=0.14^@ Clark, MgCl_2=0.035^@ Clark, and NaCl=0.035^@ Clark.
Answer» Solution :`1ppm =0.07^@` Clark So, ppm of all constituents are `CaCO_3=20ppm, MgCO_3=8ppm, CaSO_4=6ppm`, `MgSO_4=22ppm, MgCl_2=0.5ppm, and NaCl=0.5ppm` `NaCl=0.5ppm` has no constibution for hardness so it has no contribution towards `CACO_3` equivalents, `CaCO_3=20` ppm as `CaCO_3`. `MgCO_3=8ppm=(8xx100)/(84)=9.523 ppm CaCO_3Eq` `CaSO_4=6ppm=(6xx100)/(136)=4.417ppmCaCO_3Eq` `MgSO_4=2ppm=(2xx100)/(120)=1.666ppmCaCO_3Eq` `MgCl_2=0.5ppm=(0.5xx100)/(95)=0.5263ppmCaCO_3Eq` `NaCl=0.5ppm=` no contribution to hardness. LIME REQUIREMENT: `=(74)/(100)` [Temporary Ca hardness `+2xx` Temporary Mg hardness ` +` permanent Mg hardness] `=(74)/(100)[20+2xx9.523+1.666+0.5263]` `=(74xx41.2383)/(100)=30.5163ppm` `=30.5163mgL^(-1)=30.4163xx10^(6)(mg)/(10^(6))L` Soda requirment `(106)/(100)` [Permanent Ca hardness `+` permanent Mg hardness `+` free acids `-HCO_3^(ɵ)`] `=(106)/(100)[4.417+1.666+0.5263]=7.0ppm=7.0mgL^(-1)` `=7.0xx10^(6)mg10^(6)L^(-1)=7.0kg`