Grantee Research Project Results
2014 Progress Report: An On-Site Biological Graywater Treatment System Suitable for a Small Business
EPA Grant Number: SU835330Title: An On-Site Biological Graywater Treatment System Suitable for a Small Business
Investigators: Swinson, Bobbie Jo , Martin, Jack , Houser, James , Hambourger, Michael , Bandala, Erick R. , Davis, Joseph , Edge, Chase , Martin, Benjamin , Neff, Eric , Johnson, Jennifer , Willett, Howard , Roden, Elizabeth , Bethman, Travis
Current Investigators: Martin, Jack , Houser, James , Hambourger, Michael , Bandala, Erick R. , Swinson, Bobbie Jo , Davis, Joseph , Edge, Chase , Martin, Benjamin , Neff, Eric , Johnson, Jennifer , Willett, Howard , Roden, Elizabeth , Bethman, Travis , deJong, Emil , Homes, Anna Maria
Institution: Appalachian State University
EPA Project Officer: Hahn, Intaek
Phase: II
Project Period: August 15, 2012 through August 14, 2014 (Extended to August 14, 2016)
Project Period Covered by this Report: August 15, 2013 through August 14,2014
Project Amount: $89,708
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet - Phase 2 (2012) Recipients Lists
Research Category: Pollution Prevention/Sustainable Development , P3 Awards , P3 Challenge Area - Safe and Sustainable Water Resources , P3 Challenge Area - Sustainable and Healthy Communities , Sustainable and Healthy Communities
Objective:
Throughout the Phase II research period, students will be involved in creating a website for the project, as well as hold educational seminars, give class presentations relating to the proposed project and design, and present papers at conferences while preparing a paper for journal submission. The salon setting also provides an ideal setting for educating the community about ecological design concepts, specifically grey water filtration scenarios.
The objectives for Phase II were the following:
- Objective A: Continue characterization of removal efficiencies of pilot-scale system.
- Objective B: Finish and test prototype design through consultation with salon owner.
- Objective C: Install and monitor prototype system on-site in salon.
- Objective D: Outreach project to local and University community.
- Objective E: Integrate process into University curriculum.
Progress Summary:
Prototype Development and Construction
Students in the Department of Technology and Environmental Design designed a number of potential systems upon which our first small full-scale prototype was built. The prototype was a two trough system with a 20 gallon storage reservoir. Our mid-term report explains the design and testing of this first prototype. A second prototype based on the design wishes of John Mena, the owner of Haircut 101, was developed for display at the P3 Sustainable Design Expo April 24th through 27th, 2014 (see Figure 2) .
This second prototype was based on a very simple three-trough system with one trough on top of the wall in the hair salon and the other two on opposite sides of the wall. We are now in the process of building Prototype 3 which will be an exact replica of the system to be installed in the hair salon. Modifications to Prototype 3 were based on hydraulic testing of Prototype 2 and design criterion dictated by the business owner. A detailed description of Prototype 3 and the final design is in the conclusions.
Figure 2. Students with prototype 2 at the 2014 P3 Design Expo
Plants and Growing Medium
Shade and greywater tolerant plants were tested, we found that ferns and begonias (Begonia sp.) were most tolerant of the conditions. The begonia has a particular beautiful flower, and grew well even in stagnant low DO water, and showed no signs of disease. The business owner has expressed interest in growing bamboo in the system and we will test bamboo in Prototype 3. The final system is designed to allow the owner to put any type of plants he wants into the system as pots holding plants are easily removed and replaced (which also allows for quick removal of compromised plants to prevent disease or pest transmission).
Summary of Analysis
A control test with uncovered troughs, no plants and salon water was performed. Then a test with covered trough and no plants was performed and lastly trials have been performed with plants in place. Batch trials were run up to 12 days with continual recirculation.
During the Phase II funding period our measurements of water quality were based on the recent NSF/ANSI 350-2011 standard "Onsite residential and commercial water reuse treatment systems." Following this standard, the following parameters were chosen for analysis - temperature, pH, turbidity, total suspended solids (TSS), biochemical oxygen demand (BOD5), and total coliform bacteria. These tests were taken as a reasonable subset of the specifications listed in the NSF/ANSI 350-2011 standard.
For each test, Standard Methods (Standard Methods for the Examination of Water and Wastewater, 20th ed, 1998, Washington DC. Clesceri, Greenberg, and Eaton editors) were followed - temperature (SM 2550 B); pH, electrometric (SM 4500-H+ B); turbidity, nephelometric (SM 2130B); total suspended solids (SM 2540 D); 5-day biochemical oxygen demand (BOD5), (SM 5210 B); and total coliform bacteria (SM 9221 B).
Meters were obtained and calibrated for measurement of temperature, pH, and nephelometric turbidity. Standard solutions were used as quality controls to ensure appropriate measurement of total suspended solids and biochemical oxygen demand. Coliform bacteria counts have not yet been undertaken. However, arrangements have been made to use equipment in the Department of Biology for these measurements after a UV-sterilization unit is installed on the prototype living system. These new analytical methods offer a straightforward method to reproducibly assess water quality before and after filtration through the prototype model. Sample results are shown in Figure 3 turbidity, pH, BOD and TSS for the prototype with plants and for turbidity and pH with no plants in the prototype (control) in Figure 4. Turbidity will be the main criterion for determination of water quality and when the greywater will be diverted to tanks for toilet flushing.
Color from dyes has proven to be a difficult constituent to remove from the salon greywater, and since the processed greywater according to code must be colored before sending it to the toilets for reuse, it is important to reduce color in the greywater to avoid off-colored water in the toilets (we would like to have a nice pastel blue). A visiting professor, Erick Bandala, from the Department of Chemical, Food and Environmental Engineering, at the Universidad de Las Américas, in Puebla, Mexico, has been working with one of our graduate students to explore incorporating the TiO2- mediated photocatalytic process into our prototype. Dr. Bandala has extensive experience with using this process to remove color from wastewaters in Mexico.
Figure 3. Turbidity, pH, BOD and TSS change in salon grey water after circulation through prototype with plants.
Figure 4. Turbidity and pH change in salon grey water after circulation through prototype with no plants (control).
Future Activities:
A final prototype design has been arrived at through consultation with the business owner and plumbing professionals. The final design as it will appear in the hair salon is shown in Figure 5. It is a very simple three trough system that will require no modification of the wall or existing space and which will be easy to remove if the owner wishes. Key modifications have been made to the latest prototype to address concerns that had come up in the testing of previous prototypes. One is the pump. Rather than having a pump that is continually running we are using a sump pump that will automatically switch on when water levels reach a certain height in the greywater storage tank and then automatically switch off once the tank has been emptied. Also, there is a turbidity sensor that will automatically open a switch valve that will send clean water to tanks for toiulet water storage (see Figure 6). In order to ensure that plant roots will always be in water even if the system is shut down for extended periods, there is a trough within each trough where the plants are placed. Water fills those troughs first and then overflows from them into the larger trough that is drained, hence there is always water in the plant troughs (Figure 7). A large problem we had with initial prototypes was lack of DO in the greywater. We believe we have resolved that issue through the use of an inlet pipe that uses the power of the pump to diffuse large amounts of air into the pipe discharge (see Figure 8). We are currently in the process of finishing our final prototype for testing and beginning the bidding process for final installation in Haircut 101.
Figure 6. Schematic of final system design for treatment of hair salon sink greywater for reuse in toilets
Figure 7. Prototype of trough within a trough system to maintain water levels for plants
Figure 8. Demonstration of inlet pipe aeration system driven by pump.
Journal Articles:
No journal articles submitted with this report: View all 5 publications for this projectSupplemental Keywords:
Living system, greywater treatment, sustainable water management, water purification technologies, sustainable development, ecological water purification, pharmaceuticals in water, treatment technologies, sustainable urban planning, environmental planning, bioengineering, biofiltration technologyProgress and Final Reports:
Original AbstractP3 Phase I:
An On-Site Biological Graywater Treatment System Suitable for a Small Business | Final ReportThe 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.