Tuesday, June 23, 2009

Sludge Drying Beds

Sludge drying bed is used as the last step of dewatering system. Sludge of the system is dewatered on these beds by evaporation and drainage. Moreover, cationic polymer can be added to get faster and easier dewatering process. The polymer accelerates the particle agglomeration, increasing the total amount of water that can be drained and reducing the amount of water that needs to be evaporated.

Close sand sludge drying bed is used in this dewatering process. This type of beds includes gravel, sand and sludge layers. Also, at the bottom part, under the gravel layer, there are plastic pipes for the under drainage. Closed sand drying bed is chosen do to EPA.


Cindy said...

EPA has changed the comment period for public definition of solid waste.


40 CFR Parts 260 and 261

Definition of Solid Waste Public Meeting; Extension of Comment Period

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice of Public Meeting and Request for Comments; Extension of comment period.

SUMMARY: EPA is announcing an extension to the comment period for the public meeting notice published in the Federal Register on May 27, 2009 regarding the Agency's recent regulation on the definition of solid waste under Subtitle C of the Resource Conservation and Recovery Act (RCRA). The comment period is being extended 30 days to August 13, 2009. EPA is currently reviewing a petition filed with the Administrator under RCRA section 7004(a) requesting that the Agency reconsider and repeal the recently promulgated revisions to the definition of solid waste for hazardous secondary materials being reclaimed, and is soliciting comments and information to assist the agency in evaluating the petition.

DATES: Persons may submit written or electronic comments by August 13, 2009. The administrative record of the meeting will remain open for submissions until August 13, 2009.

This information came from http://www.CyberRegs.com

Magic Flute said...

hello, thank u so much for usefull posts u maid. but im searching for design consideration of "temprory storage of petroleum refinery wastes", could u plz guide me?