This is with reference to my previous log on this topic.

Background
Alcohol is stored in conventional storage tanks at site, which are non-insulated & low pressure fixed roof tanks. In this kind of storage system, there are three different types of losses of stored liquid.

1. WORKING LOSS

Losses due to displacement of inner air space during filling & evacuation. The material is lost each time during filling while fresh air intake results in additional evaporation inside the tank to maintain its partial pressure of liquid in vapor space.

2. BREATHING LOSS
Losses due to contraction and expansion of vapor space due to variation in day – night temperature. This also causes similar effect as explained above in item 1.

3. LOSSES DUE TO HEAT GAIN
Due to difference in ambient temperature & bulk liquid temperature, the material stored gets energy input through radiative & convective heat transfer from atmosphere. This is significant energy gain by the system compared to other two losses explained above.

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