Recipient Organization
Hansen Energy and Environmental, LLC
15600 N 4005 W
Garland,UT 84312-9542
Performing Department
(N/A)
Non Technical Summary
Hydrogen is considered a promising alternative clean energy source, which produces no green house gases. However, despite its clean and green nature when utilized in fuel cells and other devices, most hydrogen is currently produced primarily from non-renewable sources, such as natural gas, oil, and coal. Hydrogen can be produced through electrolysis and thermal decomposition of water, but the cost of production by these methods is even higher than those based on fossil fuels. Biological production of hydrogen, using microorganisms, is an exciting new area of technology development that offers the potential to produce usable hydrogen from a variety of renewable resource. Using anaerobic fermentation to produce hydrogen is actually a more cost-effective process and has considerable potential as an environmentally friendly practice because the process can utilize waste material or wastestreams with a negative value. The Andigen IBR anaerobic digester has the potential to
be the first flow-through system for the biological production of hydrogen. The purpose of this project is to examine the biological production of hydrogen using anaerobic digestion of food and agricultural waste when the methane forming bacteria are suppressed by pH.
Animal Health Component
20%
Research Effort Categories
Basic
80%
Applied
20%
Developmental
(N/A)
Goals / Objectives
The overall objective of this proposed Phase 1 project is to further develop technology for economical production of hydrogen from agricultural production and processing wastes. .The hydrogen will be produced by controlling the pH to suppress the methane forming bacteria. The pH will be controlled by using low pH food waste instead of chemicals, thus making the production of hydrogen more economical. A second objective will be to utilize the byproduct from hydrogen production, which is a liquid with a high concentration of volatile fatty acids (VFA), to produce methane in a pilot scale Induced Blanket Reactor (IBR). The 179 L (45 gallon) Pilot scale IBR was used in the development of high rate flow through digestion and is located at the USU Cane Dairy. Synthetic wastewater (manure) will be used for the initial lab scale trials. We will then conduct trials using real manure and food waste. Towards the end of the project period (5-6) months into project), we will add the
effluent from the hydrogen production into a pilot scale IBR commingling it with real manure to produce methane in order to obtain preliminary results for phase II of the SBIR. Because the research for phase I is in small scale all experiments will be batch digestion rather than flow-through digestion except for the final month when the effluent from the batch hydrogen production will be run through the pilot scale flow-through IBR. The objectives and sub objectives are: 1. Conduct hydrogen production fermentations using synthetic manure in lab scale and then real manure and cheese processing waste (lactose) in lab scale. The cheese whey will produce a biologically stressed mixed bacterial culture by lowering the pH to inhibit the production of methane. 2. Demonstrate quantity and quality of hydrogen that can be produced from these materials. 3. Commingle the effluent from the hydrogen production (high in volatile fatty acids) with dairy manure in a 179 L (45 gallon) pilot scale IBR
digester in order to extract more energy (methane) from the mixture. In other words this will be a two stage process producing two forms of gas 4. Obtain a goal of 50% digestion of the volatile solids when using real manure and lactose in the final two stage digestion process 5. Another goal would be to obtain a net energy gain by producing both hydrogen and methane from the same amount of substrate when compared to producing only methane 6. Complete a preliminary investigation of commercial and economic viability of using the IBR system for hydrogen production.
Project Methods
Most of the research will be conducted in the bio-engineering lab at Utah State University (USU) and/ or a pilot scale bioreactor facility at the USU Caine Dairy. Mark Greenwood will be hired by HEE to be the P. I. on the project. However, Dr. Carl Hansen (HEE vice president for research) will still oversee the entire project. Synthetic manure will be prepared according to work done previously. The synthetic manure will be of the same consistency as real manure but will be easier to work with during the preliminary research. Later in the project manure samples will be collected from the USU Caine Dairy or from other local dairies. Cheese processing waste can be obtained from Gossner Foods in Logan, Utah (a local cheese plant). A subaward has been made to Utah State University for the use of the facility(s), for equipment and supplies and for students who can sample bioreactor influent and effluent contents. Students will also perform analysis on the biogas containing
hydrogen and methane. Measurements will include chemical oxygen demand (COD), solids including volatile suspended (VSS) and total (TS), pH, biogas volume, hydrogen and methane content, Biogas hydrogen and methane content and VOA concentration will be measured using a gas chromatograph (GC) ((Hewlett-Packard, Wilmington, DE, Model 6890) equipped with a split inlet, thermal conductivity and flame ionization detectors) located at USU. COD, pH, and solids measurements will be done using standard methods. Analyses including, COD, VOA, biogas volume, and solids concentrations will be taken at least twice weekly unless the data shows more or less frequent sampling is appropriate. In order to determine the hydraulic retention time (HRT), COD, and/or VSS removal efficiency, influent flow rate will be measured volumetrically. The key bioreactor parameters, including hydraulic retention time, temperature and pH; will each be controlled and recorded. Because Phase I will still be in lab scale
during hydrogen production and then in small pilot scale during methane production the project will be carried out in batches in order to replicate the optimum gas producing conditions especially when moving from synthetic products to naturally occurring animal and food waste products. After progressing to the animal and food waste products optimum volumes and mixtures will be researched to prepare for an SBIR phase II project that will be a larger pilot scale continuous flow process for both hydrogen and methane production. The IBR is currently used successfully as a flow through system for methane production and can be accurately controlled by a computer. During phase I, each batch with different parameters will be replicated two or three times. Performance data including COD, VSS, and TS, pH, hydrogen production and methane production will be collected and analyzed to see which parameters will produce the most hydrogen. It is expected that at least six different experiments or
batches can be run in the six months of the project duration (three with synthetic manure and three with natural manure).