Liquid Waste Nitrification

Overview

File:Kendedabuilding.jpg

312x312px

The Kendeda Building, funded by the Kendeda Fund, was designed and constructed to achieve the Living Building Challenge. The challenge consists of seven petals: Place Petal, Water Petal, Energy Petal, Health & Happiness Petal, Materials Patel, Equity Petal, and Beauty Petal. The interest of the Liquid Waste Nitrification Project lies within the Water Petal. The Georgia Tech Kendeda Building achieves the water petal by "converting rainwater to drinking water, managing waste [grey] water to recharge the landscape, and minimizing stormwater runoff." However, a blackwater system is not present within this project. Instead, twelve composting toilets and four urinals were installed throughout the building to separate liquids and convert solids into a fertilizing soil which can be used for uptake by plants. The separated liquid, however, is stored within a storage tank and then collected and transported to a nearby waste water treatment plant.

Kendeda Wastewater System

The Kendeda Building's blackwater system employs waterless, Nepon foam-flush toilets and Gerber waterless urinals which drain into a set of Clivus Multrum M35 Automatic Composters located in the basement of the building.

The Clivus Multrum M35 Automatic Composter is a mesophilic composter which utilizes a long retention system for pathogen removal (NSF Certified: Standard 41). It is also equipped with a urine diversion system which introduces Nitrobacter and Nitrosomonas into the blackwater, then pumps the liquid end-product into a secondary storage tank. The solid waste is stored within the original tank where aerobic fecal decomposition takes place. The solid waste environment is carefully regulated by an automatic moistening system and 980 controller.

PROBLEM: The separated liquid blackwater is handled unsustainably, and fails to meet the standards of the Water Petal for which the building was designed.

The liquid storage tank is emptied on a monthly once basis. This requires a truck to be driven out to the Georgia Tech Kendeda Building, the liquid waste to be mechanically pumped out of the tank, the truck to be driven back to the waste water treatment plant, and finally the waste water treatment plant introduces the liquid waste into its pre-existing blackwater load, where it then follows through the typical waste water treatment cycle. Succinctly speaking, the blackwater removal method employed within the Kendeda Building is far more unsustainable than the conventional method.

File:Problem Diagram.png

Current Blackwater Treatment Protocol

Liquid Waste Nitrification Project

Project Objective: Engineer a complimentary system to the pre-existing blackwater infrastructure that treats the blackwater on site and successfully converts it into usable liquid fertilizer that can be used for the uptake of plants on and off campus.

Research Hypothesis: If liquid end-product storage tanks used in human waste decomposition practices are set to ideal nitrifying bacteria growth conditions, then nitrate by-product concentration should achieve optimal levels (per volume of liquid waste).

Research Procedure

Weekly Standard Operating Procedure

Sample Groups

SAMPLE GROUP	TEMP (℃)	pH	DO (% SAT.)	SALINITY (PPT)	PHOTOSYSTEM
CONTROL*
F1: SOMONAS	27.5℃	7.9	> 95%	< 1 ppt	UV Light
F2: BACTER	27.5℃	7.4	> 95%	< 1 ppt	UV Light
F3: JOINT	27.5℃	7.65	> 95%	< 1 ppt	UV Light

* Test conditions within Leachate Tank to develop CONTROL group properties

Georgia Institute of Technology Environmental Health & Safety Department Safety Procedure

Sample Collection

• PPE will be donned at the composter site and will include gloves, disposable lab coat, and safety glasses.

• Samples will be collected and placed inside of a Ziploc bag and then inside a transport container

• PPE will be doffed prior to leaving the composter site and placed inside the transport container

Sample Handling

• Infectious samples that have not been autoclaved will be handled inside of a BSC

• Spills and lab surfaces will be decontaminated with 70% Ethanol or other approved disinfectant

• Waste & discarded PPE will be disposed of inside a biohazard waste bin

• Infectious waste that hasn’t been autoclaved will be treated with 10% household bleach and poured down the drain

• Infectious samples will be stored in a properly labeled autoclave when not in use

Comprehensive Documentation of Research Procedure

1. Coordinate with Kendeda Building Manager, Marlin, on Collection Process
   1. Use proper PPE
      1. Disposable lab coat, disposable gloves, safety glasses
         1. Reference: Georgia Tech Environmental Health & Safety Department
   2. Collect Sample
      1. Collect 300mL of leachate w /50mL syringes [attached blunt needle]
      2. Place filled syringes in plastic bags
      3. Place plastics bag into a secondary container [cooler w/ hatches]
         1. Reference: Georgia Tech Environmental Health & Safety Department
   3. Remove PPE in compost room
      1. Dispose of PPE or place into secondary container
         1. Reference: Georgia Tech Environmental Health & Safety Department
2. Materials
   1. Biosafety
      1. Biohazard spill kit
      2. Biohazard tags
      3. 70% Ethanol
      4. Bleach
      5. Disposable gloves
      6. Disposable Lab Coats
   2. Lab Materials
      1. Test tubes [w/ vented caps]
      2. Stephenson’s Plates [Culturing Nitrifying bacteria]
      3. 12-Wells Microplates [IF]
      4. Sodium Bicarbonate
3. Laboratory Procedure
   1. Filter all samples
      1. Potential #1: Filter paper & vacuum pump/flask
      2. Potential #2: Centrifuge and pipet top liquid
      3. Potential #3: Graded granular soil [1] [2]
   2. Quantify Urea [start]
      1. Colorimetric Method [3] [4]
         1. Georgia Tech EAS Department Lab Procedures [5] [6]
      2. NMR [7]
         1. Contact: Dr. Leisen; Utilize NMRs on Georgia Tech Campus
      3. Mass Spectrometry [8]
         1. Pros: Achieve acceptable precision and accuracy (99.7∼109.7%)
      4. Calculate [Sodium Bicarbonate], [Urease], and [TAPSO] to add
         1. 2:1 ratio with [Urea]
   3. Quantify Ammonium [start]
      1. Ion-selective probe [Ideal Method]
      2. Spectrophotometric method [If conc. Isn’t high enough, use this method]
   4. Quantify Nitrate [start]
      1. HACH Kit [10mL, 2-hour duration]
   5. Quantify Nitrifying bacteria [9] [10] [start]
   6. Run tests for all beakers and keeping one as control
      1. Volume: 20 mL in 60mL beakers
      2. Salinity [Ideal: <1 ppt]
         1. TDS test
         2. Ion-selective probe
      3. pH [NaOH to ideal pH & TAPSO buffer to maintain] [11]
         1. Control: TBD
         2. Nitrobacter: 7.4
         3. Nitrosomonas: 7.9
         4. Combination: 7.65
      4. Catalyst: Urease
      5. D.O [Ideal: >95%] [12]
         1. Aquarium pump & stone
         2. Bubble air with filter
      6. Photosystem
         1. UV Light
   7. Autoclave
      1. 70 ℃, 30 minute
      2. Removes Pathogens: [E.coli, Proteus vulgaris, Pseudomonas aeruginosa, Klebsiella pneumoniae
4. Data Analysis Procedure
   1. Quantify Urea [End]
      1. Colorimetric Method [13] [14]
         1. Georgia Tech EAS Department Lab Procedures [15] [16]
      2. NMR [17]
         1. Contact: Dr. Leisen; Utilize NMRs on Georgia Tech Campus
      3. Mass Spectrometry [18]
         1. Pros: Achieve acceptable precision and accuracy (99.7∼109.7%)
      4. Calculate [Sodium Bicarbonate], [Urease], and [TAPSO] to add
         1. 2:1 ratio with [Urea]
   2. Quantify Ammonium [End]
      1. Ion-selective probe [Ideal Method]
      2. Spectrophotometric method [If conc. Isn’t high enough, use this method]
   3. Quantify Nitrate [End]
      1. HACH Kit [10mL, 2-hour duration]

Team Members

Name	Email Address	Major	Years
Aravind Ganesan	aravindgan@gatech.edu	Environmental Engineering	2019 - Current
Alison Thompson	athompson302@gatech.edu	Environmental Engineering	2019 - Current
Michelle Zheng	mzheng48@gatech.edu	Civil Engineering	2019 - Current