Grantee Research Project Results
Single-Stage Process for Biogas Purification
EPA Grant Number: SU840141Title: Single-Stage Process for Biogas Purification
Investigators: Lashaki, Masoud Jahandar , Meeroff, Daniel , Bloetscher, Fred
Institution: Florida Atlantic University - Boca Raton
EPA Project Officer: Spatz, Kyle
Phase: I
Project Period: December 1, 2020 through November 30, 2021 (Extended to June 30, 2022)
Project Amount: $25,000
RFA: P3 Awards: A National Student Design Competition Focusing on People, Prosperity and the Planet (2020) RFA Text | Recipients Lists
Research Category: P3 Awards , P3 Challenge Area - Air Quality
Description:
Biogas is a carbon-neutral source of renewable energy that may be produced by anaerobic digestion of agricultural waste, for example in small/rural communities, or collected in landfills. In addition to methane, biogas contains carbon dioxide and other ubiquitous impurities such as water vapor and hydrogen sulfide. Hence, biogas purification, to produce biomethane, is required prior to using it as transportation fuel or injecting it into natural gas grid. Whereas current biogas upgrading processes require multiple upstream units for desulfurization, drying, and biogas compression or cooling before carbon dioxide removal, we contend that FAU’s amine-modified silica adsorbents can concurrently separate all impurities.
Objective:
The objective of this research is to purify biogas in one single step using FAU’s made-to-order adsorbent materials. This research is of strategic importance to the U.S. energy security and well-being and prosperity protect the environment, and to support environmentally sustainable technologies. If funded, the senior personnel will incorporate the project into their community outreach activities and next year’s classes, namely Sustainability & Pollution Prevention and Air Pollution Control, both taught by the PI, and Civil, Environmental & Geomatics Eng. Design, taught by the Collaborators.
Approach:
Our proposed process drastically simplifies biogas upgrading using adsorbent materials engineered specifically to produce grid-quality biomethane. This innovative technology is comprised of concurrent removal of carbon dioxide, hydrogen sulfide and water vapor from the feed gas, followed by adsorbent regeneration and cooling in air before starting the subsequent cycle. Since the end users are the disadvantaged rural/small communities across the U.S. and landfill facilities which are operating through taxpayer’s money, cost efficiency is critical to ensure the viability of the technology. To address this critical piece, cost considerations have been factored in throughout the experimental design by choosing inexpensive silica as support, utilizing hot air as the cheapest purge gas available, and maximizing adsorbent lifetime through material design. While the proposed technology holds significant merit, there are scientific challenges to tackle, namely developing adsorbent materials capable of (i) simultaneous removal of all impurities from synthetic biogas, (ii) withstanding air oxidation at high temperature, (iii) achieving minimal pressure drop in the adsorption bed, (iv) stable long-term performance, and (v) successful field testing with actual biogas.
Expected Results:
Materials development lends itself to industrial engagement – after all, application should be the goal. In the last phase of the research, a large batch of the best-performing material will be tested for upgrading actual biogas generated by landfill facilities in Palm Beach County and Orange County, FL. Support letters from authorities in both counties are secured. Once developed and implemented, the process will replace current technologies, eliminating the need for (i) air injection in digester to prevent hydrogen sulfide formation, (ii) separate desulfurization unit, (iii) drying step, and (iv) biogas compression/cooling. Therefore, this integrated process will have a much smaller environmental footprint, with lower capital and operating costs compared to competing technologies. The research results will also contribute to lowering the emissions of air pollutants and odor-generating compounds, enhancing air quality and human health. Pollution prevention from this research is five-fold. If not used for biogas production, manure and organic waste in farms and landfills generate uncontrolled emissions of ammonia, hydrogen sulfide, nitrous oxide and methane, the last two being 250- and 25-fold more potent greenhouse gases than carbon dioxide, respectively (1). In addition, ammonia, hydrogen sulfide and nitrous oxide are well-known air pollutants with adverse human health impacts (2). Moreover, ammonia and hydrogen sulfide can cause severe odor issues in nearby communities (3). Once biomethane is produced, it replaces coal and oil, both of which not only emit more carbon dioxide per unit of energy produced (4), but also generate such air pollutants as sulfur oxides, mercury, particulates and hydrocarbons (5). In brief, the project outcomes will positively impact our socio-economic and environmental well-being, directly contributing to all sustainability pillars, namely economic, environmental and social.
Publications and Presentations:
Publications have been submitted on this project: View all 4 publications for this projectJournal Articles:
Journal Articles have been submitted on this project: View all 1 journal articles for this projectSupplemental Keywords:
green chemistry; treatment and emission control technologies; waste to energy; chemicals; toxics; clean technologies; sustainable development; global climate; southeast; Florida; FL; Atlantic coast; EPA Region 4Progress and Final Reports:
P3 Phase II:
Single-Stage Process for Biogas Purification | 2023 Progress 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.