Increasing MTBF for Pulp & Paper ClO₂ Applications, 20PEERS Conference

As with all industries, increasing the mean time between failures is very desirable. In the pulp and paper industry, shaft packing has been widely used. Packing is relatively inexpensive, with respect to its initial cost and ease of installation. The problem with packing is the required leakage to prevent damage to the packing and flush water requirements. In addition, since packing is in radial contact along the pump sleeve, there is significant power consumption. Typically, this power consumption is five times that of a mechanical seal.  

In the pulp and paper industry, there are many applications due to the hazard posed to personnel and the environment that packing or a single seal cannot be used. In these cases, a double seal with a barrier system is required. The barrier system pressure needs to be maintained higher than the highest potential seal chamber pressure to ensure leakage is into the process and not escaping to the environment. Due to the process temperatures (heat soak) and heat generated by the seal faces, these double seals require some type of cooling to prevent flashing at the seal faces. Typically, an API Plan 53A, would consist of a two to five gallon seal pot, with an internal cooling coil and external pressure source. In addition, the double seal will be equipped with a pumping ring to aide in the circulation on the barrier fluid.  

 Chlorine dioxide (ClO₂) is an unstable compound that is very toxic and explosive. Therefore, ClO₂ falls into the category of requiring a double seal with an API Plan 53. Most applications containing ClO2 also require special chemical compatibility with respect to the equipment used. 

This paper is a case study on successfully sealing ClO₂ applications that are both safe, reliable, and that require a simple support system.  

TAPPI conference proceedings and presentations, technical papers, and publication articles provide technical and management data and solutions on topics covering the Pulp, Paper, Tissue, Corrugated Packaging, Flexible Packaging, Nanotechnology and Converting Industries.

Simply select the quantity, add to your cart and your conference paper, presentation or article will be available for immediate download.