Calculation of exhaust gas emissions
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There are several issues that need to be resolved, or suggestions would be greatly appreciated. 1. In a reactor used for batch production, after nitrogen purging is completed, ethanol (100 kg), water (2000 kg), TiO2 (150 kg), and barium hydroxide (1800 kg) are added. The temperature is raised to 200 degrees, and the reaction proceeds for 24 hours. During this time, nitrogen is used to maintain pressure equilibrium (i.e., the saturated vapor pressure of the liquid mixture inside the reactor). Once the reaction is complete, the mixture is cooled to room temperature, after which it is transferred to the next processing unit. Question: How is the exhaust emission calculated throughout the entire process? My current calculation method: displaced nitrogen emissions (using a displacement formula as a reference) ； When calculating the material input, it is determined how much was added and how much was removed. The calculation of the exhaust gas is based on the gas-liquid equilibrium formula under theoretical conditions. During the normal reaction process, this isn’t calculated yet; currently it is assumed that no emissions occur. However, gas should be released during the reaction process, so how should this amount be calculated? I would appreciate some guidance ； Finally, the material is transferred; the amount of material transferred and the amount of nitrogen added are taken into account. The amount of gas emitted is also calculated based on the gas-liquid equilibrium under ideal conditions. 2. For a container with continuous inflow and outflow, how is the discharge volume calculated? For example, in a intermediate tank containing water and methanol, material is fed into the tank from the previous processing stage, and then the material in the tank is pumped away; overall, there is a balance between inflow and outflow, but there are certainly fluctuations in the liquid level during this process. May I ask how to calculate the exhaust emissions for this unit operation?
The first issue is that it’s a dynamic process, so it’s impossible to accurately calculate the amount of gas emitted; gas is released when pressure decreases, and nitrogen gas (along with the reaction materials) is expelled when pressure increases. The second issue is that the pressure inside the tank is controlled using a nitrogen inlet valve and a nitrogen outlet valve – an equal volume of gas is released for every volume of material that enters the tank, assuming the tank is saturated with the material inside it.