Biofilter Helps Resolve Odor Complaints

Sponsored by

The Hillsborough County Water Department's South County Regional Wastewater treatment facility in Sun City, Fla., began an expansion designed to increase its treatment capacity from 3.0 MGD to 4.5 MGD during the mid 1990's. Although structures to increase capacity were the focus of the project, odor control was given special consideration.

The existing plant headworks had been the source of odor complaints from the residents of the Sun City Retirement Village and also other residents and travelers who transit the area of the plant located along the Interstate 75 corridor. Odors associated with the plant had been an issue at local home owner association meetings with their respective county commissioner and had been scrutinized by the local regulatory officials.

The preliminary design for the plant expansion included a packed tower chemical scrubber for odor removal from the facility's headworks and anaerobic selector basins. Water department staff approached the design engineers to consider biofiltration technology for odor removal instead of a scrubber.

Department staff had purchased and installed several pre-manufactured Biocubetrademark Biofilters at pumping stations and the applications had been successful. After documenting the biofilters' performance, staff requested that a similar unit be installed at the treatment facility.

The Biocube biofilter installed at the South County Regional AWT facility has been fully operational for approximately two years. The system sees and treats an average of approximately 100 parts per million of hydrogen sulfide to achieve a 99 percent removal rate. It is estimated that selection of biofiltration for odor control over wet chemical scrubbing has saved the department in excess of $230,000 in chemical costs so far.

How It Works

The entire system operates under an induced vacuum. Air is pulled from the odorous process into a Moisture Integrator where the humidity and temperature are adjusted for optimum metabolic activity.

The Moisture Integrator consists of three trays partially filled with water. Air enters the inner cavity of the center tray, and bubbles up through a thin layer of water. An electric immersion heater heats the water when needed for freeze protection or to increase efficiency. The humidified air leaves the Moisture Integrator saturated with water vapor. The air enters the top of the biofilter and flows down through the biologically active media.

At the base of each tray a plenum evenly distributes air to maximize media productivity. The contaminants are absorbed into the liquid film surrounding the media particles. The microbes that oxidize the contaminant live in this liquid film. The oxidation process uses oxygen out of the air stream and enzymes produced by the microbes to convert H2S and other odorous compounds to sulfate, water and carbon dioxide.

The deodorized air and a small amount of water exit the bottom of the biofilter. The water and air are separated from one another in a Moisture Separator. Collected water is automatically drained off to a sanitary drain once the Separator is full. The dry air is pulled into a blower and discharged to the atmosphere through a small stack.

According to the company, overall hydrogen sulfide reduction of 99 percent or greater can be achieved with inlet concentrations up to 1000 ppm. The Biofilter media lasts over 10 times as long as activated carbon, at less than half the cost per pound.

Sponsored by

TODAY'S HEADLINES

California Water Services Co. files General Rate Case for all state districts

The California Water Service Company has filed a General Rate Case requesting authorization from the California Public Utilities Commission to increase rates to add revenues of $94.8 million in 2017, $23.0 million in 2018 and $22.6 million in 2019.

Navajo Tribal Utility Authority enters agreements to halt water pollution

The Environmental Protection Agency and the Navajo Nation EPA have announced a pair of settlements with the Navajo Tribal Utility Authority to bring its wastewater treatment facility in Window Rock into compliance with the federal Clean Water Act and Navajo Nation Clean Water Act.

2015 Buyer's Guide

WaterWorld's annual Buyer's Guide provides a handy, searchable reference of products and services to help water and wastewater industry professionals successfully plan, design, operate, and maintain their systems.

WateReuse to host 30th annual WateReuse Symposium in September

WateReuse will host its 30th Annual WateReuse Symposium on Sept. 13-16 at the Sheraton Seattle Hotel in Seattle, Wash. The event will bring together water managers and industry leaders to learn what's happening in water reuse policy, operations, technology, and public perception.

FOLLOW US ON SOCIAL MEDIA

  

 


© 2015. PennWell Corporation. All Rights Reserved. PRIVACY POLICY | TERMS AND CONDITIONS