User Data Package and Operation Test Report for the Implementation of the Sodium Sulfide/Ferrous Sulfate Process at Navy IWTPS.
Abstract
The ferrous sulfate/sodium sulfide (FS/SS) process is a treatment technology for the reduction of hexavalent chromium and precipitation of heavy metals in industrial wastewater treatment plants (IWTPs). When the ferrous ion, as ferrous sulfate, is mixed with sulfide, the hexavalent chromium is rapidly reduced to its trivalent state at a neutral pH and then precipitated. FS/SS technology can be used to replace the current hydroxide treatment chemistry. This report presents the results and lessons learned from full-scale implementation of FS/SS. The FS/SS treatment process reduced the volume of sludge generated by 20 to 30 percent, reduced the amount of treatment chemicals, and resulted in over $35,000 annual savings. Furthermore, metal sulfides tend to be two to three orders of magnitude less soluble than their corresponding metal hydroxides. This gives cleaner effluent, which helps the facility meet environmental requirements. Further benefits include the removal from the shop area of the high pressure sulfur dioxide cylinder (used in the hydroxide process), a faster and more reliable chrome reduction method, neutral pH operation that extends tank and equipment life, and less acid and caustic chemicals stored on the shop floor. As Navy activities do more with less, the FS/SS process can help meet increasingly stringent standards.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1997
- Accession Number
- ADA323448
Entities
People
- Edward Durlak
Organizations
- Naval Facilities Engineering Systems Command