Mass Balance Method Tracks Harmful Emissions
With the mass balance method, current levels of harmful chemicals, such as hydrofluorocarbons and chlorofluorocarbons, can be calculated and best predictions of future levels formulated. This information enables environmental scientists to better evaluate the rate of global warming based on the usage of emissions that contribute to the depletion of the ozone layer.
A mass balance method is used when determining the difference between the starting amount of a substance, such as refrigerant gas, and the end amount. This calculation determines how much of the chemical was used in daily operation and how much was discharged into the air.
A somewhat complicated equation is used to calculate the mass balance method, with the amount of chemicals entering a process are added to the different avenues in which these chemicals are used. Incorporating waste and accumulation, the result equates to the final amount of substance entering the atmosphere. For example, in terms of the refrigerant gas, the calculation takes the starting amount, transformation through the cooling process and the waste amount.
A facility may use the mass balance method to track the amount of substances used for a specific function. When accounting for pollutants, officials break down the substances by reference to how much enters the system, how much leaves the system, and how much is stored within.
The EPA requires the use of the mass balance method to monitor and track chemicals that have been identified as harmful. In particular contributors to air pollution, deterioration of the stratospheric ozone layer and global warming. The list includes methyl bromide, methyl chloroform, carbon tetrachloride, chlorofluorocarbons and hydrofluorocarbons.
The mass balance method is critical in designing and analyzing processes, such as refrigerant gas, as it moves its way through refrigeration, air-conditioning, or heating, ventilation and air conditioning systems. Simply put, whatever substances or chemicals enter a system must be accounted for, including what leaves the system and what accumulates within it. Therefore, in equation form, Input equals Output plus Accumulation.
There is a strict reporting procedure under the mass balance method. Facilities must report venting of hydrofluorocarbons and chlorofluorocarbons, including total inventory at the beginning and end of the reporting period, any purchases and any capacity changes.
The mass balance method incorporates several factors, such as the type and number of cooling equipment machines, refrigerant type, total refrigerant discharge and any leaks. The equation identifies mass flows that would have been difficult to measure otherwise, for example evaporated substances, leaks, or chemical reactions.