Implementing arsenic treatment
AdEdge Technologies, Inc. was selected in 2004 to implement full-scale arsenic treatment for the Chateau Estates mobile home community in Springfield, Ohio. The public water system has approximately 230 connections with an average daily flow of 45,000 gal per day (gpd).
The company was contracted by the U.S. EPA to perform a turnkey project, including design, fabrication, permitting, installation and startup of the treatment facility. To address the concerns of local residents, the host site worked closely with the Ohio EPA (OEPA) to permit and implement a cost-effective treatment solution as soon as possible. The AdEdge team prepared the design documents and obtained all regulatory permits from OEPA to install a two-stage treatment system that would reduce high iron and arsenic levels below new standards in the two wells serving the mobile home park.
The system utilizes AdEdge’s AD26 and granular ferric oxide (GFO) adsorption system using Bayoxide E33 . Building and system upgrades were also performed before the system was installed and placed into full-time operation during Sept. 2005.
The arsenic treatment train consists of a completely integrated packaged treatment system with two main modules to treat a 230 gpm design flow: an AD26 system for iron and manganese removal and an adsorption package unit (APU) for arsenic adsorption that is both skid-mounted and automated. The first module in the treatment train is the iron/manganese removal system, which consists of a triplex 30-in. diameter vessel system and AD26 media. The AD26 system is augmented with the chlorine feed module prior to the treatment system. This module injects, monitors and controls free chlorine to enhance iron and manganese oxidation and filtration prior to arsenic polishing.
The second component is an arsenic adsorption skid-mounted unit rated for 230 gpm that is configured in parallel operation. Raw water is pumped from the two groundwater supply wells through the AD26 pretreatment unit to hydropneumatic tanks. Next, it goes through the triplex APU adsorption system before entering the distribution. The 42-in. diameter APU vessels each contain Bayoxide E33 adsorption media, also known as GFO. AdEdge has used GFO media in over 50 small community and noncommunity public water system applications and in over 2,000 residential applications throughout the U.S. and Canada.
The skid-mounted systems are equipped with automatic controls, backwashing features, switches, gauges, flowmeters and sample ports for complete functioning packaged units. A PLC and color touch screen interface allow for simple user access and operation. Since operations began in late September 2005, results indicate a decrease in iron from 1.1 to 1.6 mg/L to <0.03 mg/L. Manganese was reduced to <0.01 mg/L while arsenic levels decreased from 28 parts per billion (ppb) to below detection at <2 ppb.