A methane explosion on March 24 at the Goshen (Ind.) Wastewater Treatment Plant was likely caused by methane buildup in the plant’s digester area. The explosion occurred around 5 a.m. before staff had arrived, so no one was injured.

“The damage is pretty extensive,” says Dustin Sailor, the city utility engineer. “When it ignited, it moved all four walls with the heaviest damage to the west and north. It happened so early in the morning, we’re just thankful nobody was here. It had to have been loud do that to a building.”

The methane reportedly leaked from an overflow pipe into the sewer system and built up in the plant’s sludge thickener building, where it ignited. Inspectors have narrowed down the ignition source to either the motor of the gravity belt thickener or a heater located in the same room as the thickener.

“The room going into the belt thickener had a sewer line that was not trapped,” says Sailor. “So when the gas from the bubbles came out, that was the easiest place for it to go into that building.”

Plant operation has not been hindered, but the building suffered extensive damage, including walls, doors, overhead lighting and most of the electrical. Supports have been installed to ensure the ceiling doesn’t collapse.

“We may make some changes to the structure and the electrical,” says Sailor. “But our goal is to make it a safer situation.”

Source: The Elkhart Truth, Goshen News

Joint Recycling Program Earns EPA Award
The Los Angeles County Sanitation District and the Inland Empire Utilities Agency, a Chino, Calif., municipal water agency, received an environmental champion award from the U.S. Environmental Protection Agency for a joint recycling program. The project has recycled more than 1 million tons of green waste and biosolids and produced more than 1 million cubic yards of compost since the plant opened in 2007.

“Sometimes, these partnerships are great in concept, but when you put them together, the governance issues get in the way,” says San Pedroza, spokesman for the sanitation districts. “Not in this case. The two agencies work together well.”

The two agencies formed the Inland Empire Regional Composting Authority and built a recycling plant that combines biosolids with food, yard and waste from horse stables to create a compost material that is sold to landscapers and other contractors.

The two agencies are working with the Association of Compost Producers to promote the program to other counties and states.

Source: Long Beach Press Telegram

Stanford University Breaks Ground on Resource Recovery Center
Construction on a $3 million resource recovery center began on March 25 at Stanford University. The university plans to test and scale up reclamation technologies on campus, which could then be used in California’s water-strapped cities.

Stanford’s student and faculty population produces about 1 mgd of wastewater, which Tom Zigterman, the associate director for water services and civil infrastructure, hopes to reduce.

“We could reclaim easily half of that,” he says. “Half a million gallons a day would make up for a shortfall in a drought restriction and also help us meet our future water supply needs going forward.”

The center will possibly focus on advanced treatment technologies that recover energy and high-value materials from wastewater, using portable units that can be tested by municipal systems. Researchers are hoping to push new technologies out faster, perhaps testing small systems within two years.

“It usually takes 10 years in this field to do something like this,” says Craig Criddle, a professor of civil and environmental engineering. “We need to work faster.”

Source: Stanford Woods, Environment & Energy Publishing

Omaha Reduces Odor Problem with Reused Pipes
A network of recycled sewer pipes and pumps will finally solve an industrial wastewater odor problem in Omaha, Neb. Planning for the $39 million project began in 2008, with the goal of reducing bacteria in the Missouri River. The system went online this month, connecting seven factories and pushing industrial wastewater to the city’s Missouri River Wastewater Treatment Plant.

The new system reuses piping from an old wastewater plant that was closed decades ago.

The city separated the industrial-area sewers from other Omaha sewer systems, sending industrial wastewater into two new water-treatment tanks where it will be treated as high-strength industrial wastewater. Improvements to the plant also include an increased ability to handle stormwater surges, which ensures wastewater goes through proper treatment.

“It is clear to us that achieving a 30 percent pollutant reduction with less than a $40 million expense in a $2 billion program makes this project a tremendous value for our ratepayers, a lot of bang for the buck,” says Marty Grate, Omaha’s environmental services manager.

Source: Omaha World-Herald

A Phosphorus Magnet?
Researchers from Germany’s Phosphorus Platform DDP, working through the Fraunhofer Institute for Silicate Research, have developed a method to remove and retrieve phosphorus from wastewater with superparamagnetic particles.

The process could help clean water and achieve appropriate discharge levels while recovering the mineral for fertilization applications.

The particles, which are non-magnetic under normal conditions, are added to phosphorus-polluted wastewater where they bond with phosphorus anions. When exposed to a magnetic field, the particles become magnetic and then they, along with the anions, are removed from the water simply using a magnet. The wastewater is left phosphorus-free, and the phosphorus is retrieved for secondary use.

The technology could be tweaked to remove other pollutants such as heavy metals.

Source: Red Orbit, Fraunhofer Press Release