Performing Department
(N/A)
Non Technical Summary
Ammonia emissions are one of the major air quality concerns at the global, national and regional levels. Ammonia emissions from poultry farms account for 27% of the U.S. total atmospheric ammonia emissions. High ammonia levels are a concern both inside and outside the poultry house; it is a precursor of acid rain and significantly compromises poultry welfare. It is not just malodorous, but has significant hazardous effect on the health of caretakers. Ammonia levels are particularly important during winter in cooler climates where ventilation may be reduced to conserve heat. Therefore, there is a great need to reduce ammonia emissions from poultry farms to reduce the harm to animal and human health and the environmentIn this SBIR project, TDA Research, Inc. (TDA) is developing a sorbent and catalytic ammonia conversion system that integrates a high-capacity ammonia sorbent and an ammonia oxidation catalyst together into a single system to remove ammonia from poultry house air down from 20 Parts per Million (ppm) or more to the Parts per Billion (ppb) levels and then convert the adsorbed ammonia into benign gaseous nitrogen and water vapor, eliminating the need for disposal. TDA's ammonia removal system is a simple drop in solution that can be integrated into existing poultry (and other animal) farm air handling systems. TDA's system will control the NH3 emissions from poultry farms, keeping them to less than 1 Parts per Million (ppm) in the exit air. The process is continuous and simple, providing uninterrupted ammonia removal. This system could also be used to maintain low ammonia levels (less than 20 ppm, the recommended maximum ammonia level for chicken health is 25 ppm) in poultry houses (and other indoor animal housing facilities).The new technology is a simple, affordable, automated drop-in solution for mitigation of high ammonia levels found in poultry houses. It will not disrupt the regular day to day functioning of the farm as seen with other ammonia removal technologies. TDA's system uses an energy efficient system similar to ones long used in building HVAC (Heating, ventilation, and air conditioning) systems to increase the energy efficiency and provide humidity control. In the poultry farm case, the same system design is adopted to house ammonia removal sorbent and catalyst while reducing the size and pressure drop (concerns with current technologies). TDA's technology platform can potentially be expanded later to also control humidity inside poultry houses and other animal housing facilities.In the Phase I effort, we demonstrated a high regenerable ammonia adsorption capacity of > 3.4 mg/cc (i.e., 3.4 kg NH3 removed per m3 of sorbent) with a thermal swing of between adsorption at 30 and desorption at 250°C at a very high space velocity of 108,000 h-1. During the Phase II project, we will design and fabricate a sub-scale prototype of ammonia remoal unit to fully demonstrate the technology under simulated poultry air at TDA for a minimum of 1,000 hours. In Year 1 we will work with an academic Poultry Science Department to do multiple sub-scale test campaigns of 2-3 weeks each to obtain data on our prototype assembly's performance.
Animal Health Component
20%
Research Effort Categories
Basic
(N/A)
Applied
20%
Developmental
80%
Goals / Objectives
In this SBIR project, TDA Research, Inc. (TDA) is developing a bi-functional sorbent and catalytic ammonia conversion system that integrates a high capacity ammonia sorbent and an ammonia oxidation catalyst (together called SorboCAT) in a single system to remove ammonia from poultry house air down from 20 Parts per Million (ppm) or more to the Parts per Billion (ppb) levels and then convert the adsorbed ammonia into benign gaseous N2 and water vapor, eliminating the need for disposal.In the Phase I work, we successfully completed all of our bench-scale proof-of-concept demonstrations for both the sorbent and catalyst proposed for the SorboCAT (a bi-functional sorbent/catalyst) system, elevating the TRL to 3. In Phase II, we will further optimize and scale-up the sorbent and catalyst's production and improve its physical properties (such as crush strength and attrition resistance). We will scale-up and prepare a minimum of 1 kg of the sorbent, utilizing high throughput production equipment to accelerate the rate of production and/or batch size. We will prepare the sorbents and support them on engineered structures such as honey comb wheel or monolith, or into 3D printed structures for use in the wheels. We will carry out multiple adsorption/ desorption cycles to demonstrate the cycle life (running a minimum of 2,000 cycles). Finally, we will design and fabricate a sub-scale prototype of the SorboCAT unit (including the ammonia removal wheel and the integrated catalytic oxidizer) to fully demonstrate the technology under simulated poultry air at TDA for a minimum of 1,000 hours. In Year 1 we will work with University of Georgia (UGA) Poultry Science Department to do multiple sub-scale test campaigns of 2-3 weeks each to obtain data on the SorboCAT prototype assembly's performance. This subscale test campaign will involve birds at 1 bird/sq.ft. in the room, and monitoring their weight gain, feed conversion and the ammonia levels. In Year 2 UGA will assist in hosting a field test campaign that will include a minimum of 2 flocks of birds with each flock being about 5-6 weeks (about 1,600 hours). In these field trials, UGA will monitor and collect house environmental data (temperature, relative humidity, and ammonia concentration) in the poultry house; UGA has the ammonia sensors needed for this effort. Based on the results, a more detailed engineering and cost analysis will be completed. Upon Phase II completion, the expected technology readiness level (TRL) will be increased to 6.
Project Methods
This Phase II effort will be divided into 8 technical tasksTask 1. Sorbent/Catalyst Preparation & CharacterizationWe will optimize the chemical composition, physical properties and mechanical integrity of the sorbent and catalyst. We will use raw materials that are widely available in bulk quantities and at low cost in the synthesis process. The production process will then be optimized using scalable production methodology.Subtask 1.1 Synthesis: We will prepare several sorbent / catalyst formulations using various sources of active materials, zeolite substrates and additives (i.e., clays, binders. We will first screen these formulations and measure their physical properties including porosity, surface area, crush strength and active material content. The samples that meet physical screening criteria will be further tested to measure their ammonia adsorption capacity in Task 2.Subtask 1.2 Deposition on Engineered Supports: We will optimize methods for adding TDA's SorboCAT ammonia removal sorbent onto the structured/engineered structures so that they can be used in the sorbent wheels.Subtask 1.3 Sorbent Characterization: We will extensively characterize the sorbent. We will measure surface area by BET, crystalline structure by x-ray diffraction (XRD), surface morphology by SEM and bulk composition by x-ray fluorescence (XRF), as appropriate.Task 2. Sorbent/Catalyst TestingIn this task, we will carry out tests to identify (i) the ammonia removal capacity (adsorption), and (ii) oxidation of the adsorbed ammonia using various concentrations of ammonia in air. Ammonia concentration of less than 10 ppm is beneficial for the broilers (Naseem 2018). We will test NH3 concentrations in the range of 5-50 ppm.NH3 Adsorption Tests: We will monitor the concentrations of ammonia at the inlet and exit of a test cell to measure the ammonia removal efficiency. For these experiments, we will first use a test cell to evaluate the intrinsic activity of the sorbents in removing ammonia. The most promising samples will then be prepared on monolithic sorbent wheels and evaluated in test cells that incorporate different size reactors that allow us to carry out representative tests at the desired reactor geometry (e.g., bed depth, cross-sectional area, monolith wheel cell density). Obviously, the sorbent bed has a minimum depth requirement (i.e., sufficiently long gas-solid contact time) to achieve high ammonia removal efficiency, which must be balanced against pressure drop generated by ventilation blower. We will identify the flow area and bed configuration while ensuring full removal of ammonia. Humidity will be maintained at 50% RH +/- 10% depending on building temperature and pressure. We will carry out tests at temperatures ranging from 5 to 50°C. We will vary space velocity, temperature, humidity level and ammonia concentration to assess sorbent performance in parametric tests.NH3 Oxidation Tests: After the ammonia has been adsorbed, we will evaluate the oxidation performance of the catalyst. We will flow heated air (and NH3/air) through the sorbent and monitor the exit gas for ammonia conversion and product selectivity (unreacted NH3, NOx). In this subtask we carry our experimental conditions as mentioned above, but at temperatures of 100 to 250°C, as there will be a trade-off with conversion and selectivity. Our objective is to get >95% ammonia conversion with less than 100-200 ppm NOx.Task 3. Multiple Cycling & Long-Term TestingThe initial capacity screening and limited cycle testing of the sorbent candidates will allow us to identify a single-best structured sorbent formulation. We will fabricate sub-scale wheels for evaluation. We will carry out any necessary modifications to an existing bench-scale sorbent wheel test unit at TDA and test the NH3 sorbent wheel under representative conditions of practical operation. We will measure the NH3 capacity of the sorbent at optimum conditions: flow, cycle time, adsorption and regeneration temperature. We will then repeat the experiments for a minimum of 2,000 adsorption and regeneration cycles.Task 4. Prototype Design & TestingIn this task, TDA will design a sub-scale prototype of the closed loop NH3 removal unit with all auxiliary equipment that supports the operation of the system The unit will demonstrate not only the operation of the sorbent under simulated operation conditions, but also the effectiveness of the integrated heat exchanger (and confirm the heating and cooling rates) to provide and remove heat from the sorbent wheel to facilitate adsorption and regeneration within the designed cycle time.Task 5. Prototype Testing at UGA Poultry Research Center (UGA Experiment 1)When we run the test of the prototype unit, the broilers will be housed in one room at the UGA Poultry Research Center. The bird density will be 1 sq.ft/bird. Birds will have unlimited access to food and water. The birds will be placed on used litter which is the source of ammonia. The birds would continue to add manure and moisture to the litter driving the ammonia generation rate. The room's relative humidity will be set to maintain a level over 70% to help increase litter moisture and subsequent ammonia production. Temperature and relative humidity sensors will be placed in the room to monitor the room environment. Ammonia would be monitored using a ammonia sensor. The TDA unit will be installed and operated on a schedule of 48 hours on and 48 hours off to determine the how well the unit worked at reducing ammonia concentration. The study would continue for 3-5 weeks and be repeated in two trials.Task 6. Prototype Field Study at Industry Broiler Farm (UGA Experiment 2)We will conduct a field study on an industry contract broiler farm in Northeast Georgia. Two houses on the farm will be used. One will be the treatment house with the TDA SorboCAT unit installed and operating to reduce ammonia concentrations and the other would be a control house. The houses will be 40'x500' and have use pine shaving litter. The house and bird management will be operated according to the farmer and integrator broiler rearing protocols. Temperature, relative humidity, ammonia concentration and bird water consumption would be monitored throughout the flock. A minimum of two flocks would be monitored during the cold weather months (October-March). Temperature and relative humidty data would be monitored with temperature and relative humidity sensors and ammonia would be monitored using a ammonia sensor. Water consumption would be measured by using a pulse datalogger connected to the house water meter.Task 7. System Analysis and CostingBased on the material performance in the bench-scale tests, TDA will design the full size SorboCAT ammonia3 removal system. Key features will include: 1) size of the wheel/reactors housing the monolithic wheel sorbent, 2) thickness of the sorbent housing vessel and material of construction, 3) loading/distribution of wheel zones i.e., adsorption, oxidation, preheating, cooling zones and pressure drop, and 4) size the sub-systems such as blower, heat exchangers, and air heater. We will then carry out a cost analysis to assess the economic potential of the system. We will quantify the cost benefits of TDA's ammonia removal system and compare the cost against other ammonia control options such as additives to manure, acid scrubbers, biofilters etc.Task 8. ReportingTDA will submit progress reports as required in the USDA Phase II contract and a comprehensive final report will be provided at the end of Phase II.