Progress 09/01/11 to 08/31/13
Outputs
Target Audience: We have met and spokenwith a number of municipal wastewater treatment plant and agriculteralanaerobic digestor opporators and project develpoersat meetings andwere selected to present atconferencessuch as the2013BioCycle West Coast Conference, 2013 California Water Environment Association Conference, Orange County/Islesponsored TAG meeting. We have also met with representitives from Waste Management, Inc., Caterpillar, and GE.We have received requests for proposals from biogas project developers such as Harvest Power, Anaergia, and Ag Power Group. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? Both Michael Matelich and Seth Burns developed professionally through interaction withdairy managementand technology providers in developing a successful demonstration project. Additionally, interaction with potential customers and presenting to various trade groups has provided addtional professional development for both Seth Burns and Michael Matelich. How have the results been disseminated to communities of interest? We maintain an informative webpage at www.biogasandelectric.com. We wrote and widelydistributed a whitepaperoutliningthe progress and results we obtained during the project period at our dairy-based demonstration project. We have attended a number of industry conferences as invitedspeakers and given presentations covering our process and results. We have also maintained an informative booth at several of these conferences. What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
Goals A & B The full scale NOxRx® demonstration facility was installed at a 3,500 head flushed lane California based dairy. The site was equipped with a stirred, covered lagoon type anaerobic digester of approximately 30 million gallons. A biogas stream of 75 - 150 scfm is produced by the digester. The biogaswas passed through a coiled-loop chiller to condense and remove water prior to combustion. The H2S concentration varies between 6,000 ppm and 15,000 ppm. No specific sulfide removal was employed prior to combustion. The full biogas stream is used to power a 300 kW Guascor lean burn CHP biogas engine.Biogas & Electricdesigned and installed a solution to treat the exhaust from the biogas engine. The results from Phase II are encouraging. Using untreated wastewater fromthis dairy based anaerobic digester, Biogas & Electric was able to reduce NOx to levels that meet the California Air Resource Board 2007 standard of 0.07 lbs. per MW-hr. or 2-3 ppm. This NOx level is better than Selective Catalytic Reduction (SCR) the current Best Available Control Technology (BACT) which is technically capable of reducing NOx levels to the 9-11 ppm level. Goal C The following table is an estimate of energy consumption used by the NOxRx® process: Voltage Amperage Watts Kw Oxidant #1 220 7 1540 1.5 Oxidant #2 220 7 1540 1.5 Exhaust fan – 3 HP 460 5 2300 2.3 (Drain) Sump Pump – 5 HP 460 7 3220 3.2 Supply Pump – 5 HP 460 7 3220 3.2 11.8 Table 3 - Energy Consumption of NOxRx® The energy demands for a NOxRx® solution will be dependent largely on how far wastewater needs to be pumped to and from the project, which varies from project to project. If electricity is $.07 per Kilowatt Hour, the operating cost of NOxRx® for the Bullfrog Farms installation can be calculated as follows: 11.8 Kw x 24 hours/day x $.07/Kw = $19.86/day or $7,248/year. The current leading technology is SCR or Selective Catalytic Reduction, requires H2S removal from the biogas prior to combustion. Bullfrog Farms has looked into H2S reduction solutions, and has determined that an H2S reduction system is prohibitively expensive for their operation. A cost comparison between SCR and NOxRx® can be summarized below: Selective Catalytic Reduction (SCR) NOxRx® CAPEX: $ 100,000 CAPEX: $ 250,000 H2S Removal System: $ 300,000 H2S Removal System: $ - OPEX: $ 25,000 OPEX: $ 7,250 Interest Rate: 6% Interest Rate: 6% Project Term (years): 10 Project Term (years): 10 Net Present Value: ($561,361) Net Present Value: ($289,210) Year Cash Outlay Year Cash Outlay 1 $ (425,000) 1 $ (257,250) 2 $ (25,000) 2 $ (7,250) 3 $ (25,000) 3 $ (7,250) 4 $ (25,000) 4 $ (7,250) 5 $ (25,000) 5 $ (7,250) 6 $ (25,000) 6 $ (7,250) 7 $ (25,000) 7 $ (7,250) 8 $ (25,000) 8 $ (7,250) 9 $ (25,000) 9 $ (7,250) 10 $ (25,000) 10 $ (7,250) Table 4 - Cost Comparison of SCR vs. NOxRx® Furthermore, many biogas project developers in the San Joaquin Valley have had difficulty with SCR systems reliably meeting the existing NOx regulations of 9-11 ppm, indicating that the technical limit of SCR is 9-11 ppm. NOxRx® has demonstrated reproducible operation for extended periods of time at 2 ppm NOx, indicating a technical limit of at least 2 ppm. Thus, NOxRx® is more economical, and it also more effective than SCR, the current Best Available Control Technology in many air districts across the nation. Goal D Host test site requirements and infrastructure limitations precluded continuous, unattended operation of the system, therefore this task could not be accomplished as written. However, effluent samples were obtained and analyzed after prolonged periods of attended operation (hours). Changes were detected in pH and ORP consistent with the amount of SO2 absorbed. No measurable differences were detected in otherwater chemistry (ie analysis for nitrate; only difference was pH and Sulfate).
Publications
|