Grantee Research Project Results
Final Report: An On-Site Biological Graywater Treatment System Suitable for a Small Business
EPA Grant Number: SU836015Title: An On-Site Biological Graywater Treatment System Suitable for a Small Business
Investigators: Houser, James , Swinson, Bobbie Jo , Gropper, Alexis , May, Erik , Downey, Erin , Wallach, Hannah , Martin, Jack , Trowbridge, Jamie , Johnson, Jennifer , Kenny, Jillian , Hauser, Katarina , Williams, Megan , Hambourger, Michael , Winkler, Robin , Roark, Stephanie
Institution: Appalachian State University
EPA Project Officer: Hahn, Intaek
Phase: I
Project Period: August 15, 2011 through August 14, 2012
Project Amount: $14,988
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2011) RFA Text | Recipients Lists
Research Category: Pollution Prevention/Sustainable Development , P3 Challenge Area - Sustainable and Healthy Communities , P3 Challenge Area - Safe and Sustainable Water Resources , P3 Awards , Sustainable and Healthy Communities
Objective:
Researchers at Appalachian State University proposed to create a biological on-site graywater treatment system for a small business in Boone, NC to help conserve fresh water and reduce the business water bill. The business was the salon Haircut 101. Phase I research was designed to show proof-of-concept. In Phase I our objective was to demonstrate that a biological treatment system, or “living system”, would be able to lower the concentration of contaminates in salon graywater coming from the sinks where hair treatments and shampooing occur. In addition we wanted to start the process of designing the actual prototype system that would be installed in Haircut 101. To this end we had the following objectives:
- Determine and cultivate appropriate plants for a living system.
- Collect and determine the chemical composition and quantity of salon graywater.
- Perform batch tests on plants using salon wastewater samples to determine removal efficiency and effects on plants.
- Prepare, operate and determine removal efficiency of pilot-scale living system.
- Design prototype systems for installation in the actual salon business site.
- Education and outreach about biological on-site graywater treatment systems.
Research was conducted to ascertain the type of plants best suited for a “living system”. Plants where purchased and grown in a hydroponic system within one of the University greenhouses. Our research utilized an existing “living system” constructed at the University’s biodiesel processing laboratory in a small greenhouse. The greenhouse was built with previous funding from the EPA P3 grant program to biologically treat wastewater from a biodiesel production facility. Due to upgrades at the facility, however, the system was available for research purposes. This system was ideal for the proposed research and testing purposes, offering a very efficient startup.
The tanks and ponds of the “living system” were cleaned out entirely in August 2011, and new plants and plumbing was installed. Wastewater collected from the salon in Objective 2 was the influent wastewater for the living system. The pilot-scale living system had the following configuration: 1) Salon wastewater was collected in a 350 gallon settling tank as it passed through a low maintenance filter to collect hair and larger solids. 2) Gravity flow then fed water from the settling tank through a fine screen into an open aerobic tank. This 120-gallon tank was filled with Lemna, commonly known as duckweed, which helped to encourage catabolic degradation of organic compounds and surfactant removal from the salon wastewater. 3)The water then flowed by gravity into a secondary open aerobic tank occupied by Pontederia cordata. 4) After leaving this tank water flowed by gravity into the first wetland cell which contained a diverse ecosystem of Juncus effuses, Typhaangustifolia, Loliummulti florum, and Medacago sativa. Water flowed vertically into the top of the wetland via distribution piping and simultaneously flowed horizontally via gravity as it filtered its way through a pea gravel substrate with this mixture of species. 5) Finally water flowed into the final open pond filled with floating aquatic plants including Pistia stratiotes (water hyacinth) and Eichhornia crassipes (water lettuce).
In addition to testing the removal efficiency of the overall system, individual plants were batch tested to determine their ability to reduce concentrations of contaminants in salon graywater. Plant health during these tests was monitored using qualitative criteria (e.g. color, size and robustness) and fluorescence measurements. Concentrations of contaminant in the salo graywater was determined with a Gas Chromatograph Mass Spectometer.
Interior Design students in the Department of Technology and Environmental Design developed prototype designs of the on-site “living system”, showing how the system could be aesthetically integrated into the business space.
An important objective of the research was to educate students and the public about environmental engineering that uses natural biological processes to prevent pollution and save resources and to assess the public’s perception of on-site treatment systems. To that effect confidential surveys were administered at the salon by researchers to obtain informative data on the acceptance of alternative graywater reclamation systems.
Summary/Accomplishments (Outputs/Outcomes):
Objective 1: Numerous plants were identified, purchased and successfully grown from both seedlings and seeds in the hydroponic system purchased for Phase I and in the “living system”. The plants used were Lemna, commonly known as duckweed, Pontederia cordata, Juncus effuses, Typhaangusto folia, Loliummulti florum, Medacago sativa, and the floating aquatic plants Pistia stratiotes and Eichhornia crassipes. An early infestation of aphids in the “living system” was controlled by a ladybug infusion.
Objective 2: Based off of water consumption records of the salon from November 15, 2007 until November 10, 2010, an average of 7,190 gallons of water are pulled from the city water supply per month (Public Utilities, 2010). To reduce the consumption by just half would save 43,140 gallons of water a year, a significant number for a small business.
Plumbing alterations were made at Haircut 101 allowing for wastewater from the shampoo bowls to be easily collected in five-gallon watertight containers by research students. The amount of water used for various salon services was measured. The chemical composition of the salon graywater was determined using a gas chromatograph mass spectrometer (GC Mass Spec). There were hundreds of chemicals identified in the graywater. For purposes of batch testing four classes of salon water were decided on based on salon service records and typical salon services. These were classified as color, perm, relaxer, and haircut.
Objective 3: The plants present in the “living system” were tested for efficacy in the phytoremediation of salon wastewater contaminants. Toxicology batch tests were performed with the four classifications of salon water outlined in Objective 2. Plant health was quantified by fluorescence measurements. Wastewater collected from the salon in Objective 2 was used for batch testing individual species’ remediation potential.
Removal efficiencies were seen to be between 30 to 85 percent over three days and 60 percent to complete removal over eight days.
The plants themselves seemed to thrive in the salon graywater samples. They became greener and more vigorous. Chlorophyll florescence readings quantitatively confirmed this qualitative observation
Objective 4: The retention time of the “living system” was approximately 22 to 26 hours (about a day long). Salon wastewater was released from its 325 gallon storage/settling tank into the “living system” full of non-salon graywater. Samples were taken every two hours for the first 12 hours, then every four hours until the 24 hour period. After the initial 24 hours samples were taken every 12 hours. The system was run for three days. All samples were taken from the 325 gallon settling tank as water from the outlet of the “living system” was pumped back to this tank before re-entering the inlet of the system. Taking into account the normal dilution of the 325 gallons of salon graywater with the approximate 500 gallons of water in the “living system”, removal of contaminates was observed to be up to 40 percent with one pass through the system (24 hours).
Objective 5: Appalachian State graduate and undergraduate Interior Design students in the Department of Technology and Environmental Design presented a number of scalable prototype designs for an indoor, point-of-use biological water treatment and reclamation system suitable for various small business settings. The designs were incorporated into the building itself; increasing the value of the establishment as “living” art, while functioning as a filtering and recycling system for graywater. The filtered water could then be reused for toilet flushing, laundry, irrigation, and possible other on-site uses as building codes allow
Objective 6: Educational materials on graywater treatment, recycling, and limitations of ecological systems were made available to the student body and community. Articles in the school newspaper as well as all three local newspapers informed much of the community about the research and stirred interest about alternative solutions to the growing water availability and treatment problem in Boone, NC. In addition, salons serve as a gathering place where many people come together to socialize and discuss current politics and trends. Environmental trends and policy are no exception. Researchers had the opportunity to interact with the community, namely the salon clientele, and educate on the importance of balanced economic, social, and ecological cycles. Confidential surveys were also administered at the salon by researchers to obtain informative data on the acceptance of alternative graywater reclamation systems. The results of those surveys show that 72% of survey participants think that water is important and must be conserved, while 44% of those surveyed are somewhat concerned about the water quality in Boone. 48% of those surveyed strongly agree that they feel completely comfortable with water from the shampoo sinks being used to flush toilets while an additional 14% agree (but not strongly).
Conclusions:
Batch testing of the individual plants found that they removed a significant amount of contaminants from the salon graywater samples without exhibiting any deleterious effects. In fact, the plants seemed to thrive in the graywater. The overall living system also did not exhibit deleterious effects from the salon graywater and appeared to remove constituents. There is no doubt that the plant-soil system removed significant amounts of pollutants from salon water samples. The exact fate of these compounds is unknown however, whether they are being adsorbed by soil and root surfaces or being incorporated and transformed within the plants themselves. Fluorescence studies and qualitative assessment of plants indicates that there is a growth benefit provided by salon water samples. It is still inconclusive as to how large the prototype system or how many times the water would have to be recirculated through the system to be considered adequately treated for re-use in toilets or laundry systems. The criterion for adequate treatment for such uses is not well established. We assume an aesthetic standard for toilets (e.g. clear, odorless and non-caustic water) and a functional criterion for laundering (e.g. non-caustic or detrimental to fabrics, as well as odorless and dye free). Determining an effective standard for such water re-use will be part of the Phase II determination.
Further studies on the pilot-scale greenhouse system will be performed as Phase I draws to a close in August 2012. Ultimately the prototype systems will need to be individually evaluated for effectiveness before final installation on-site. Parameters from the Phase I research, however, have permitted us to make the following approximate conclusions about prototype system size and retention time to match removal efficiencies of the pilot-scale system and batch tests. The system should be able to handle about 300 gallons of graywater per day and create a retention time of 24 to 48 hours which will probably indicate the need for recirculation through the system. By the end of Phase I testing these approximate estimates will be more refined.
Meanwhile, the survey illustrated that 72% of survey participants think that water is important and must be conserved, while 44% of those surveyed are somewhat concerned about the water quality in Boone, and over 60% feel comfortable with water from the shampoo sinks being used to flush toilets. The enthusiasm for this project among students has been tremendous and has involved students from multiple disciplines and programs. The owner of Haircut 101 has also been an enthusiastic partner and has expressed interest in the initial prototype designs for the on-site “living system”. The potential of creating a functional living work of art that helps conserve his water, save him money and add to the overall aesthetic ambience of his business is an exciting proposition.
Supplemental Keywords:
living machines, sustainable water management, water purification technologies, sustainable development, ecological water purification, pharmaceuticals in water, treatment technologies, sustainable urban planning, environmental planning, bioengineering, biofiltration technology, closed loop recycling, conservation, design for the environmentRelevant Websites:
Student receives EPA P3 grant for project to reclaim gray water from small businesses Exit
P3 Phase II:
An On-Site Biological Graywater Treatment System Suitable for a Small BusinessThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.