Optimizing the performance with improved capture efficiency

Background

The customer is prominent in the aluminum foil processing industry. They produce foil products with various thickness and quality margins for pharmaceutical and flexible packaging industries all over the world.

Process overview
Aluminum foil is produced by rolling slabs cast in a rolling mill to desired thickness. It is a heat sensitive process and large amount of thermal energy is released from various production stages. The fumes coming out from this process needs to be filtered for removal of harmful chemicals, hydrocarbons, and VOCs before it is vented to atmosphere.

Customer’s Requirement
Munters´ mist elimination systems are virtually everywhere there are liquids and gases that need to be separated. Munters´ systems have provided satisfactory results for many customers with similar applications.

For this project, the customer was looking to remove more than 95% of VOC from the exhaust gases with a low pressure drop in the system. They encountered high solvent loss in the form of carryover, which needed immediate attention. The existing system had limited space constrains to accommodate new equipment, and the flow thru this exhaust gas system was horizontal, which made the design a challenge.

Solutions provided
The Munters´ mist eliminator required an accurate hydraulic check and all the available Munters´ models were considered.

The inlet flow thru fume exhaust system was as high as 60,000 m³/hr. This exhaust air contained the liquid particles of the oil used in the rolling process. System dimensions were limited to fit where the mist eliminator needed to be installed along with supporting frames.

The Munters´ DH 5000 series mist eliminator was selected for horizontal flow. The droplets impinge onto the profiles, where they form a liquid film which is subsequently drained off because of gravity.

Specially shaped separating chambers ensure that the liquid is drained off correctly, while at the same time enhancing the separation of these very fine droplets. With accurate hydraulic calculations, we designed the mist eliminator to provide a required efficiency of more than 95% and a pressure drop of as low as 30 mm WC.