# Calculate the Amount of Lime (85% Pure) and Soda (95% Pure) Required to Soften One Million Litre of Water Which Contains Caco3 = 12. 5ppml Mgco3 = 8.4ppml - Applied Chemistry 1

Numerical

Calculate the amount of lime (85% pure) and soda (95% pure) required to soften one million litre of water which contains CaCO3 = 12. 5ppml MgCO3 = 8.4ppml
CaCl2 = 22.2ppml ,  MgCl2 = 9.5ppml C02 = 33ppml HCI = Z3ppml  organic matter= 16.Bppm

#### Solution

 lmpurities(mg/lit) Multiplication factor CaC03 equivalent(mg/lit) Requirement CaC03=72.5 100/100 12.5xx 100/100 = 12.5  L MgC03=8.4 100/84 8.4 xx 100/84= 10 2L CaCl2 = 22.2 100/111 22.2 xx 100/111 = 20 S MgCl2 = 9.5 100/95 9.5 xx 100/95 = 10 L+S C02 = 33 100/44 33 xx 100/44=75 L HCl = 7.3 100/73 7. xx 100/73=10 L+S

Nacl  does not react with lime and soda.
LIME=74/100 [caC0_3  "equivalent of " 2 xx MgC0_3 + CaC0_3 + MgCl_2 + HCl+CO_2 ] xx

("volume of water")/ 100 xx 100/ (%"purity")

74 /100 =xx [2 xx 10 + 12.5 + 10 + 10 + 75] xx 10^6/1000 xx 100/ 85

= 111000 gms.

SODA =106/100  [caCO_3 " equivalent of " CaCl_2 + MgCl_2 ] xx ("Volume of water")/ 1000 xx 100/("%purity").

= 106/100  [20 + 10] xx 10^6/1000 xx 100/95.

= 33473.68 qms.

The lime requirement is 111000 gms and soda requirement is 33473.68 gms.

Concept: Softening of water by Hot and Cold lime Soda method and numerical problems
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2017-2018 (June) CBCGS

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