Navigation Links
Pressure cooker on steroids treats human waste
Date:7/9/2013

DURHAM, N.C. -- Like alchemists, engineers from Duke University and the University of Missouri are developing a process to turn sewage into drinkable water, energy and useful byproducts at a cost of less than a nickel per person per day.

In addition to the technological aspects of the project, the researchers are investigating plans to make the technology economically self-sustaining in developing countries, since many areas with the greatest sanitation challenges are typically urban and low-income. The new approach will operate without connections to water, sewer or electrical lines.

The Bill & Melinda Gates Foundation is supporting the team's efforts with a $1.18 million grant as part of the Reinvent the Toilet Challenge. Researchers expect that a working prototype will have been constructed at Duke in 15 months. It will be tested first in the U.S. and then deployed in South Africa, India or Ghana, depending on the results of ongoing feasibility studies.

"We not only want to design and build the right piece of equipment to improve sanitation, but one that is well-integrated into its community, both economically and socially," said Marc Deshusses, professor of civil and environmental engineering at Duke's Pratt School of Engineering and principal investigator of the project. "We expect the end products of the process will be used by the communities to build businesses that make it self-sustaining."

The proposal is to produce a self-contained "toilet" unit that can be transported to locations overseas in a 20-foot container. The prototype will have the capacity to handle the daily fecal waste of about 1,200 users collected from community centers or neighborhood latrines directly piped or transported to the facility for processing.

Deshusses, who received a grant from the Gates Foundation in 2011 to develop a novel sanitation system for the developing world, describes the technology that powers the process as a "pressure cooker on steroids." The technology behind the proposal is known as supercritical water oxidation (SCWO).

"When you heat water above 705 degrees Fahrenheit under pressure, it becomes a 'supercritical fluid,' thicker than steam but less dense than water," said co-principal investigator William Jacoby, associate professor of biological engineering at Missouri and director of its Carbon Recycling Center. "When we add oxygen to the process, it quickly 'burns up' any carbonaceous materials, including human waste."

Jacoby said that the SCWO process has been used to treat hazardous wastes, such as polychlorinated biphenyls (PCBs) and chemical weapons.

"In terms of human waste, the process is faster than other treatment methods, and it produces hot, and potable, water and excess energy in the form of heat," Jacoby said.

The reaction produces clean water, heat, carbon dioxide, benign salts and nitrogen, which can be used by the community or turned into business opportunities to support the system, the researchers said. For example, the water could be used in community showers or clothes-washing facilities and the heat could generate electricity.

While one team of engineers works on the technical aspects of the project, another will work in parallel on developing business plans to make the endeavor feasible not only economically, but also from a regulatory and cultural standpoint.

"The technology to treat the waste is not necessarily low-tech, but it is very sustainable, with no adverse environmental impacts, so our challenge is to make it cost-effective and self-sustaining," said co-principal investigator Jay Golden, who directs Duke's Center for Sustainability & Commerce. He is also on the faculty of Pratt and Duke's Nicholas School of the Environment.

"By working with people on the ground, we'll develop a plan for linking the system and its byproducts to specific community needs," Golden said. "More broadly, we'll try to identify other regions where our model can be effectively duplicated."


'/>"/>

Contact: Richard Merritt
richard.merritt@duke.edu
919-660-8414
Duke University
Source:Eurekalert

Related biology news :

1. Efficacy of acupressure to relieve migraine nausea presented at International Headache Congress
2. Study links chemicals widely found in plastics and processed food to elevated blood pressure in children and teens
3. Researchers use graphene quantum dots to detect humidity and pressure
4. Cocktail of multiple pressures combine to threaten the worlds pollinating insects
5. Molecular hub links obesity, heart disease to high blood pressure
6. Prenatal exposure to pesticide DDT linked to adult high blood pressure
7. Omega-3s from fish vs. fish oil pills better at maintaining blood pressure in mouse model
8. Bioliq pilot plant: Successful operation of high-pressure entrained flow gasification
9. Blood vessels sniff gut microbes to regulate blood pressure
10. New risk factor identified for high blood pressure during pregnancy
11. Antioxidants may ease PAD blood pressure increase
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/7/2016)... June 7, 2016  Syngrafii Inc. and San ... relationship that includes integrating Syngrafii,s patented LongPen™ eSignature ... This collaboration will result in greater convenience for ... union, while maintaining existing document workflow and compliance ... ...
(Date:6/2/2016)... The Department of Transport Management (DOTM) ... million US Dollar project, for the , Supply ... Enrolment, and IT Infrastructure , to ... implementation of Identity Management Solutions. Numerous renowned international vendors participated ... was selected for the most compliant and innovative ...
(Date:6/2/2016)... Perimeter Surveillance & Detection Systems, Biometrics & ... & Other Service  The latest report from ... of the global Border Security market . Visiongain ... billion in 2016. Now: In November 2015 ... and hardware technologies for advanced video surveillance. ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... ... June 27, 2016 , ... ... medical technologies, services and solutions to the healthcare market. The company's primary focus ... distribution, manufacturing, sales and marketing strategies that are necessary to help companies efficiently ...
(Date:6/27/2016)... 27, 2016  Liquid Biotech USA ... of a Sponsored Research Agreement with The University ... (CTCs) from cancer patients.  The funding will be ... correlate with clinical outcomes in cancer patients undergoing ... then be employed to support the design of ...
(Date:6/24/2016)... discussions on a range of subjects including policies, debt and ... Poloz. Speaking at a lecture to the Canadian ... to the country,s inflation target, which is set by both ... "In certain areas there needs to be ... why not sit down and address strategy together?" ...
(Date:6/24/2016)... ... June 24, 2016 , ... While the majority of commercial spectrophotometers and fluorometers ... the 6000i models are higher end machines that use the more unconventional z-dimension of ... beam from the bottom of the cuvette holder. , FireflySci has developed several ...
Breaking Biology Technology: