Calculation of atmospheric emissions from naphthalene storage tanks

To calculate the volume of emissions we must know the change in temperature of the gas space of the naphthalene storage tanks during operation. It is obvious that this temperature will depend on the temperature of the product. Knowing this relation we can determine the temperature of the gas space from the temperature of the liquid. These temperatures were measured at different points of the gas space and product with chromel-copel thermocouples with a KSP-4 potentiometer at different times and at different filling levels. The results of the measurements are presented. Analysis of the graphs indicate that the temperature of the gas space clearly depends on the temperature of the liquid and differs from it by 10-15°C. A change in product level in the storage tank changes the temperature by 2-4°C. Calculation of the mean daily volume of emission caused by by 'minor aspirations,' was carried out according to formula. For a storage tank with a volume of the gas space of 300 m3 and a sum of temperature rises of 2.3°C the mean daily volume of emissions is 1.9 m3. The volume of emissions to the atmosphere during 'reverse expiration' depends on the ratio between the rates of arrival of air into the storage tank during a reduction in liquid level in it and heating, i.e., its saturation with product vapors in the gas space. When these rates are equal there will be no 'reverse expiration'.