Source: TDA RESEARCH, INC. submitted to
DESULFURIZATION OF BIOGAS DERIVED FROM ANIMAL MANURE
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
0218108
Grant No.
2009-33610-19707
Project No.
COLK-2009-00198
Proposal No.
2009-00198
Multistate No.
(N/A)
Program Code
8.11
Project Start Date
Jun 1, 2009
Project End Date
Jan 31, 2010
Grant Year
2009
Project Director
Alptekin, G.
Recipient Organization
TDA RESEARCH, INC.
12345 WEST 52ND AVENUE
WHEAT RIDGE,CO 80033
Performing Department
(N/A)
Non Technical Summary
TDA is developing a cost effective and flexible desulfurization technology to clean-up biogas generated from waste streams fuels that allow its use in highly efficient fuel cell-based combined heat and power systems. Better and efficient use of these under-utilized biowastes could replace major amounts of natural gas to reduce the U.S. dependence on foreign energy resources consumption of hydrocarbon in the U.S. and lead to significant reductions in CO2 emissions, a potent greenhouse gas.
Animal Health Component
(N/A)
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
4033910202010%
5113910200020%
5113910202010%
1413910200020%
1413910202010%
5115399200030%
Goals / Objectives
Animal farms generate by-product gases containing billions of Btu energy; this energy is either not used at all or used in old and inefficient processes. Better use of these under-utilized streams could replace significant amounts of natural gas, thereby reducing the U.S. dependence on foreign energy resources and significantly reducing emissions of carbon dioxide (CO2), a potent greenhouse gas. TDA Research Inc., in collaboration with FuelCell Energy Inc., proposes to develop a new, high capacity, expendable sorbent to remove sulfur species from ADG, thereby providing an essentially sulfur-free biogas that meets the cleanliness requirements of DFC power plants. Unlike the combustion engines, the fuel cells operate with very high efficiency even at small scale, offering significant benefits to the distributed CHP systems utilizing bio-waste.
Project Methods
TDA will develop a new sorbent that will operate downstream of a bulk desulfurization system (as a polishing bed) and remove any residual H2S and all other organic sulfur species from the biogas. This will be an enabling technology for the small-scale fuel cell-based CHP systems to operate on biogas feedstock as an alternative to natural gas. A successful sorbent - one that achieves a high sulfur capacity and removal efficiency - reduces the operating costs associated with sorbent replacement and the labor burden required for the change outs.

Progress 06/01/09 to 01/31/10

Outputs
OUTPUTS: TDA is developing a highly effective sorbent that can remove sulfur compounds from simulated biogas streams with very high capacity. Our sorbent bed is used as a polisher that is located downstream of a bulk desulfurization system to remove any residual hydrogen sulfide (H2S) and all other organic sulfur species (e.g., mercaptans, sulfide, disulfides). This will be a key technology that enables the use of biogas in distributed fuel cell CHP systems. In Phase I, we synthesized and tested a large number of sorbent formulations to identify the ones with high sulfur capacity and removal efficiency. TDA's sorbent achieved over 35% wt. capacity for H2S and over 4% wt. capacity for mercaptans and other organic sulfur compounds. The large pores of the support also allowed us to effectively remove the large disulfide species (e.g., dimethyl disulfide) that are difficult to remove using conventional microporous sorbents. The new adsorbent could reduce the sulfur concentration of the gas to less than 4 ppbv to ensure maximum protection to the fuel cell. We also demonstrated that we could regenerate the sorbent for multiple adsorption/regeneration cycles, which may be a potential advantage in larger installations (over 20 MW). PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: Because its properties are similar to those of natural gas, biogas produced by the anaerobic digesters (referred to as anaerobic digester gas or ADG) is often used to meet the heating demands of the farm, dairy or food processing facilities. In a potential CHP application, the biogas generated from manure is combusted in a boiler/steam turbine combination to generate both electricity and useful heat. The electricity demand varies greatly depending on the size of the facility and the nature of the process. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
In a preliminary engineering and cost analysis, we showed the economic viability of the new sorbent used as an expendable sulfur polishing bed for a fuel cell CHP system. For a typical 2,000 cow dairy, we estimated the added cost of desulfurization to be less than 0.36 cents/kWh. The overall impact of the gas clean-up system on the cost of electricity (COE) is small contributing less than 3.4% to the COE (based on a cost of the electricity in California for industrial use of 10.56 cents/kWh in 2009).

Publications

  • No publications reported this period