Reverse Osmosis Demineralization Replacement

Project Description

Port Townsend Paper had an in-situ separate train demineralizer water system feeding three separate boilers. Their system was old, unreliable, and prohibitive repair and maintenance costs facilitated a full system replacement. A technology provider was selected to provide a single pass system capable of flows from 500 to 800gpm. Sacre-Davey’s primary scope of work was integration of these units within the mill and detailed design for ancillary system requirements. Multimedia Filtration and Reverse Osmosis (RO) Water Demineralization Replacement System. Sacre-Davey Engineering successfully completed all aspects of the design packages utilizing 3D modeling software, multidisciplinary industrial boiler feedwater expertise, and mill management/operator communication to successfully provide an integration solution for the demineralization replacement system.

Scope of Work

The SDE engineering team produced an IFC (issued for construction) package that included all work necessary to demolish existing systems and install each new equipment skid (activated carbon filters, sand filters, and reverse osmosis) for proper operation of the demineralization process. This included process, mechanical/piping, structural, electrical and instrumentation/controls.

Challenges

Two adjacent rooms were selected by the mill to place the equipment skids as the existing system was still in operation. Site investigation confirmed that the rooms were very small for the size of the skids and that they had very limited structural support. Limited room meant additional pipe routing and instrument location challenges for the engineering team.

A secondary challenge was to provide an in parallel commissioning, start-up and “hot” switchover plan.

Solutions

SDE’s solution was two-fold: provide an accurate and representative 3D model to isolate and identify interferences and relocate smaller equipment to adjacent unused areas maximizing room spacing. Helical piles were specified to support the 100-year-old floor and where piles could not physically be installed, structural foam was employed. Additionally, SDE utilized previous hot switchover experience to schedule tie-in activities and provide operations with detailed step-by-step procedures.