Issue link: https://www.e-digitaleditions.com/i/1386347
camfi lapc.com US Pharmacopeia 18 The most effi cient reverse pulse clean- ing systems use on-demand cleaning. A controller reads the dP across the fi lters and initiates a cleaning cycle au- tomatically when the dP reaches a tar- geted value, to return the dP to a stable level. A suitable receptacle stores the collected dust and allows emptying of the container when necessary without having to shut down the dust collector. However, the pulse cleaning process can cause pressure disturbances in dirty air ducting and in the process machine to which it's connected. Dust collection system suppliers can design a system to prevent such disturbances by using proactive strategies such as: • Reducing the compressed air pressure • Segmented fi lter designs • Off-line cleaning regimes • Automatic dampers All of these techniques can be de- signed into the system to help prevent pressure issues. Energy Effi ciency In continuous manufacturing, energy effi ciency is a primary consideration for the design of all ancillary equipment, in- cluding the dust collectors. Dust collec- tors consume energy in two main areas: the fan and the fi lter cleaning system. Fan. The fan produces negative pressure that effectively draws in the dust and air from the process equipment and re- moves the generated dust. Well designed dust collection systems have well-bal- anced and -designed ducting to minimize the fan's power consumption. Using vari- able-frequency drives and high-effi cien- cy motors can also reduce energy con- sumption signifi cantly. Filter cleaning system. Compressed air is expensive to generate. A more effi - cient fi lter cleaning process will have a lower average dP and will consume less compressed air. Consider the following factors when selecting an energy effi - cient dust collector for your application: Bag-in/bag-out containment systems use the safe change fi lter replacement method while the discharge uses continuous liner technology. • The fi lter media should effectively release accumulated dust during fi lter cleaning. Each type of fi lter media has unique characteristics that you need consider for each application. • The fi lter cartridge design should en- courage dust release during cleaning and maximize the amount of usable fi l- ter media. • The pulse cleaning mechanism should be designed to minimize compressed-air usage while still effec- tively cleaning the fi lters. Compact Design Small process machines and reduced fl oor space require small ancillary equipment. This includes dust collec- tors and the cartridge-style fi lters that dry dust applications typically use. Cartridge-style fi lters have a greater surface area and smaller footprint than bag fi lters. In addition, dust collectors typically need to incorporate a HEPA fi lter and a fan, which can take up valuable space in a production fl oor or suite. Using a fully integrated, compact dust collec- tion system is a space saving strategy that is sometimes a necessity. A more compact unit can also have much lower installation costs. Safety Features You must evaluate a continuous man- ufacturing process before implemen- tation to determine its potential health and safety risks. With dust collection, the main risks involve the potential exposure of workers to harmful dusts, cross contamination of other products, and fi res or explosions from com- bustible dust. A well-designed and well-maintained dust collection sys- tem can remove airborne dust from the workspace.