- Wastewater Minimization and Treatment
Burns & McDonnell evaluated options to improve the performance of a Resource Conservation and Recovery Act (RCRA)-regulated refinery wastewater treatment unit. The objective of the modifications was conformance with the standards set forth in 40 CFR 60 and 61. The evaluation considered changes in the refinery and wastewater treatment unit.
Several options to reduce wastewater flow from 1,100 gallons per minute (gpm) to 800 gpm were identified; thereby, minimizing the cost of wastewater treatment plant modifications and making the refinery more water efficient. Options included automation of cooling tower and boiler blow-down, crude desalter modifications, condensate recovery, and reclamation of stripped sour water.
An initial front-end planning effort identified two methods of reducing benzene concentrations in wastewater: conversion of the ABTU(s) to an enhanced biodegradation unit (EBU) and installation of crude unit benzene stripper. The refinery elected to install a benzene stripper based upon economic considerations.
A second front-end planning effort was initiated to improve the organic compound removal efficiency of the wastewater treatment unit. Improvements recommended included increased off-test equalization capacity, secondary oil removal with dissolved gas flotation (DGF), and replacement of the ABTUs with moving bed biofilm reactors (MBBR). Front-end planning level 3 was completed for a 2,000 gpm DGF unit with the following ancillary equipment: pump stations, chemical feed systems, power distribution center and RTO.
- Regulatory support
- Wastewater minimization
- Front-end planning