PrekotAC as a new filter aids material for fabric filter in air filtration system

Fabric filter has a short life span due to wear and tear influenced by the operating conditions of the system. Treatment of fabric filter using pre-coating material is one of the simplest technique to overcome this problem where it works as a filtration aids that will coat a layer of inert material onto the surface of the fabric. Pre-coating acts as a barrier to block and remove undesired particles from gas stream but allowing a uniform air flow passing through the filter media. The morphology of dust cake that accumulated on the surface of the filter media depends on several properties of the particles such as shape and size. Hence, study presents the characterization of a newly formulated filtration aids known as PrekotAC consisting of a different combination of pre-coating material PreKot™ and activated carbon. The aim is to determine the best combination of PrekotAC admixtures as a filtration aids suitable for a fabric filtration system. Various characteristics of the formulated admixtures such as its particle size distribution, bulk density, moisture content as well as its morphology were investigated and presented in this paper

The characteristics of a formulated filter aids for fabric filters

The characteristics of a formulated filter aids material known as PrekotAC were investigated in this study. PrekotAC does not merely act as a flue gas cleaning agent but also as an efficient dust separation material to be used in a fabric filter system. PrekotAC was formulated based on the combination of PreKot™ and activated carbon with four different weight ratios of 10:90, 20:80, 30:70 and 40:60, respectively. The relationship between pressure drop and the characteristics of the newly formulated filter aids in terms of filtration velocity, permeability and material loading across a filter media was investigated. The results showed that pressure drop across a filter media decreases as the amount of PreKot™ content in the mixture increases. It was observed that the formulation of PrekotAC 40:60 gave the lowest pressure drop compared to the other combinations. The characteristics of the PreKot™ itself, which are fluffy and multi-cellular in nature help to form a porous filter cake layer during the filtration process. Furthermore, the particle size distribution of the formulated PrekotAC which is well balance leads to the formation of a porous cake with high permeability even under high filtration velocity or material loading conditions

Performance of PrekotAC Filter Aids on Pressure Drop across Two Different Filter Media

A study on the performance of formulated PrekotAC filter aids on pressure drop across two different types of filter media, i.e polytetrafluoroethylene (PTFE) and polyimide (P84) was carried out in a laboratory scale fabric filtration system. Filter aids is applied in order to prolong the lifespan of the fabric filter by reducing the pressure drop across a filter cake. PrekotAC which is a combination of 90%wt activated carbon and 10%wt PreKotTM was tested under various material loadings of 0.2, 0.4, and 0.6 mg/mm2 at a constant filtration velocity of 5 m/min across its cake and filter media. The results showed that PrekotAC presents a lower pressure drop across the P84 compared to PTFE filter media under various material loadings. This is because of its different characteristics that effect the porosity of the filter media and allow a higher volumetric airflow passing through, resulting in lower pressure drop compared to PTFE filter media. In addition, the diversity in terms of particle size distribution of the formulated PrekotAC that increase its permeability property helps to reduce the pressure drop across the media and its filter cake. Thus, PrekotAC has a promising characteristic as a two in one filter aids, a pre-coating and adsorbent material for fabric filtration system

Filter aids influence on pressure drop across a filtration system

Filter aids is commonly used to reduce pressure drop across air filtration system as it helps to increase the efficiency of filtration of accumulated filter cake. Filtration velocity is one of the main parameters that affect the performance of filter aids material. In this study, a formulated filter aids consisting of PreKot™ and activated carbon mixture (designated as PrekotAC) was tested on PTFE filter media under various filtration velocities of 5, 6, and 8 m/min at a constant material loading of 0.2 mg/mm2. Results showed that pressure drop is highly influenced by filtration velocity where higher filtration velocity leads to a higher pressure drop across the filter cake. It was found that PrekotAC performed better in terms of reducing the pressure drop across the filter cake even at the highest filtration velocity. The diversity in different particle size distribution of non-uniform particle size in the formulated PrekotAC mixture presents a higher permeability causes a lower pressure drop across the accumulated filter cake. The finding suggests that PrekotAC is a promising filter aids material that helps reducing the pressure drop across fabric filtration system