And There's Sludge

One of the systems revisited at the plant was the sludge-handling system, which had gone through a number of changes and evaluations. An air dryer was added in 1991 to the air supply of the double-diaphragm sludge-press feed pump. Despite the fact that it was located inside the building, the pump would oc...

03/01/2001


One of the systems revisited at the plant was the sludge-handling system, which had gone through a number of changes and evaluations.

An air dryer was added in 1991 to the air supply of the double-diaphragm sludge-press feed pump. Despite the fact that it was located inside the building, the pump would occasionally freeze up during cold weather and the smaller air dryer originally installed was solely for the air supply to air-operated valves.

Another change made was that the original sludge-cake chute was replaced with one featuring baffles to better distribute the sludge cake into the roll-off container below the sludge press.

Sludges from the inclined plate settler, American Petroleum Institute (API) units and dissolved-air flotation units are mixed together in a sludge holding tank. It was found that by having the chrome wastewater settled and dewatered separately, the wastewater-treatment plant could be considered a small-quantity generator. Unfortunately, there was not enough floor space available to install a separate sludge press for the chrome sludge.

Additionally, a precoat system that was originally furnished for the sludge press is now used for acid-washing the sludge press because the sludge press has performed well without one. Another surprise is that the filter-press cloths have been changed only once since construction due to a longer than expected cloth life and the benefits of an acid-washing system.

Aisin's operators are now considering air-drying the sludge cake to reduce the disposal costs that are based on weight rather than volume.

Return to "Withstanding the Test of Time"





Consulting-Specifying Engineer's Product of the Year (POY) contest is the premier award for new products in the HVAC, fire, electrical, and...
Consulting-Specifying Engineer magazine is dedicated to encouraging and recognizing the most talented young individuals...
The MEP Giants program lists the top mechanical, electrical, plumbing, and fire protection engineering firms in the United States.
2017 MEP Giants; Mergers and acquisitions report; ASHRAE 62.1; LEED v4 updates and tips; Understanding overcurrent protection
Integrating electrical and HVAC for energy efficiency; Mixed-use buildings; ASHRAE 90.4; Wireless fire alarms assessment and challenges
Integrated building networks, NFPA 99, recover waste heat, chilled water systems, Internet of Things, BAS controls
Transformers; Electrical system design; Selecting and sizing transformers; Grounded and ungrounded system design, Paralleling generator systems
Commissioning electrical systems; Designing emergency and standby generator systems; VFDs in high-performance buildings
Tying a microgrid to the smart grid; Paralleling generator systems; Previewing NEC 2017 changes
As brand protection manager for Eaton’s Electrical Sector, Tom Grace oversees counterfeit awareness...
Amara Rozgus is chief editor and content manager of Consulting-Specifier Engineer magazine.
IEEE power industry experts bring their combined experience in the electrical power industry...
Michael Heinsdorf, P.E., LEED AP, CDT is an Engineering Specification Writer at ARCOM MasterSpec.
Automation Engineer; Wood Group
System Integrator; Cross Integrated Systems Group
Fire & Life Safety Engineer; Technip USA Inc.
This course focuses on climate analysis, appropriateness of cooling system selection, and combining cooling systems.
This course will help identify and reveal electrical hazards and identify the solutions to implementing and maintaining a safe work environment.
This course explains how maintaining power and communication systems through emergency power-generation systems is critical.
click me