Thickening DianeGarvey has experience with a wide variety of thickening technologies. The following is a description of a few ofthese projects. Thickening; State-of-the-Art Status Report - Technical Writer and Editor 1999-2000- As a subcontractor,worked on several EPA technical reports on; dissolved air flotation thickening,gravity thickening, belt press dewatering and thickening, centrifuge dewateringand thickening, recessed chamber and membrane filter press dewatering. Each report includes information on processdescription, applicability, advantages, disadvantages, operation, maintenance,costs and references. Eachtechnical report involved a literature survey and phone calls to operatingfacilities to verify long term performance and quantify operation andmaintenance demands. Gravity Thickening 1995 - Project Engineer for biosolids thickeningoptimization program for New Rochelle, New York. Sampled and tested biosolids for preliminarydesign of gravity thickening and storage. Using the WRC design method it was found that the existing thickener wasover designed and long detention time resulted in solids floating rather thansettling. Specialized laboratory testswere used to determine if WAS should be combined with primary solids to improvethickening and to determine optimum design for the solids collectionsystem. Automation and instrumentationallowed for a shorter detention time, a higher sludge blanket and optimizationof consolidation forces. Althoughconventional gravity thickening results in variable performance at best, thenewest design methodology and modern instrumentation allows improvedperformance with minimum energy demands and low operation and maintenance costs. Evaluation of ThickeningAlternatives 1997 - Leadinvestigator for Upper Montgomery Joint Authority municipal wastewatertreatment plant thickening evaluation. The benefits of thickening at this plantincluded increased detention time in digesters and reduced costs for haulingand land application or disposal of liquid biosolids. Alternatives evaluated included rotary drumthickening, gravity belt thickener, centrifuge thickening and a no actionalternative. The costs evaluatedincluded capital, O&M labor, monitoring, electricity, polymer, hauling costs,land application costs and tipping fees. The report also provided detailed information on operating experience atother facilities and demonstrated performance on similar types of wastewatersolids. InnovativeGravity Thickening 1992- Project Manager for residualsremoval facility for the Lower Bucks County Joint Municipal Authority, Levittown, Pennsylvania.This innovative design provided the client benefits from a simple in linepolymer blending and injection system, a spiral bottom collector,instrumentation and automation which allowed higher sludge blankets, lowerdetention times, smaller tank size and ultimately 8-10% solidsconcentrations. The thickened andpolymer conditioned solids were then fed to a recessed chamber filter press fordewatering. The resultant 40% solidscake saved the client money in reduced trucking and end use or disposalcosts. Ms. Garveys involvement includedtechnical and economic evaluation of the technology, planning, design,construction management, preparation of O&M Manuals, commissioning,startup, and process optimization services for this 10-mgd water treatmentplant thickening and dewatering facility. Dissolved Air Floatation Thickening 1993- Managerof dissolved air flotation (DAF) facility design and construction for the LowerBucks County Joint Municipal Authority, Levittown, Pennsylvania. Provided design and construction managementof a wastewater solids thickener for this 10‑mgd wastewater treatmentplant. During the design phase Ms.Garvey had the opportunity to visit over a dozen operating facilities andinterview the operators. The informationgathered was used to optimize design and facilitate reliability and ease ofoperation. |
