Installation of Agitators in Open Vessels (e.g., Kettles)
Installation of agitators in open vessels should occur as follow (Moerman &
- • Stirrers, homogenizers, or mixers installed via the bottom side or a side wall require sealing of the shaft at the product side. The problem is that seals may wear with time resulting in leakage of product to the outside and product contamination. Parts of the seal may get lost in the product as a foreign body contaminant (Fig. 6.17). Moreover, when the seal gets damaged, product buildup around the shaft will occur, providing nutrients for microorganisms to grow. These microorganisms may subsequently flow back into the product.
- • Where mounting of the equipment outside the product zone is possible, the mixer used to mix open product should be fixed beside the equipment, not only to prevent the contamination of the product with dripping oil, but also to avoid the introduction of soil, and concomitantly spoiling microorganisms and pathogens into the product along with overhanging electrical cabling (Fig. 6.18).