(90c) Novel Aboveground Neutralization System

Part of a billion-dollar project at one of the chemical manufacturing facilities in the US gulf coast, two new ion exchange (IX) trains were added with six other existing. The existing neutralization system processes regeneration wastewater from the existing IX trains. The system was experiencing problems achieving the desired pH due to inefficient design of the pit system. Existing pit system processes dilute as well as acid/caustic rich streams from IX regeneration. Due to inadequate pit volume and sensitivity of pH fluctuation with addition of acid/caustic made pit operations very inefficient. Complete regeneration of one train was not feasible. This impacted the production capacity of the demineralized water further affecting the process plant capacity. Moreover, the problem intensified after the addition of two new IX trains. Initial proposal from the plant was to add three aboveground tanks to hold larger regeneration volumes, but the major drawback was high cost and larger plot space requirement. By diverting some of dilute wastewater streams to disposal, a single above ground tank neutralization system with an eductor was proposed to save capital cost and plot space. Inadequate volume problem was solved by diverting some of the dilute streams to disposal and only neutralizing water streams with measurable acid and caustic contents. Based on rigorous literature research, there is a great need for debottlenecking methods and optimization of existing neutralization setups in the industry. Improving neutralization process, IX regeneration stream analysis, and reducing environmental impact are some of the key objective of this project.