Final Report: Highly Efficient Water Management System for Lignocellulosic Biomass

EPA Contract Number: EPD12024
Title: Highly Efficient Water Management System for Lignocellulosic Biomass
Investigators: Kelly, John T.
Small Business: Altex Technologies Corporation
EPA Contact: Manager, SBIR Program
Phase: I
Project Period: March 1, 2012 through August 31, 2012
Project Amount: $79,490
RFA: Small Business Innovation Research (SBIR) - Phase I (2012) RFA Text |  Recipients Lists
Research Category: Small Business Innovation Research (SBIR) , SBIR - Sustainabile Utilization of Biomass


The energy requirement for the removal of biomass moisture in the form of liquid is small compared to the removal of water in the form of evaporated moisture. Altex has developed an innovative process, known as HEWMS, to remove moisture present in the biomass in liquid form. In this project, Altex has developed laboratory-scale equipment to prove the technical feasibility of the HEWMS process by showing the potential to remove moisture present in the biomass to a level suitable for field storage of biomass. Different biomass materials like switchgrass, miscanthus, yard waste and ethanol industry residues were tested successfully in the laboratory-scale equipment. Also, the energy reduction potential of HEWMS process for moisture management, compared to conventional drying, was calculated. The measured data were used to determine the economics of operation of HEWMS systems having processing capacities of 10,000 to 30,000 tons/year.

Summary/Accomplishments (Outputs/Outcomes):

For the switchgrass, miscanthus, yard waste and ethanol plant residues tested under this effort, moisture reductions of 52.4%, 72.0%, 50.7% and 63.0%, respectively, were obtained using the HEWMS process. These are substantial reductions achieved with energy use reductions of 53.2% to 60.5 %, versus conventional evaporative drying, as well as with corresponding priority pollutants and greenhouse gas reductions. Also, economic analyses for several cases showed that the HEWMS concept is economically feasible. Considering both capital and operating costs, HEWMS reduces drying costs per ton by 54%, 52%, and 47%, versus conventional drying for plant capacities of 10,000 tpy, 20,000 tpy and 30,000 tpy, respectively. These are substantial savings that will drive the commercial use of HEWMS.


Tests on dewatering of lignocellulosic materials and other biomass materials have shown the technical feasibility of the HEWMS concept. HEWMS can affect a broad range of biomass materials within the agricultural and forest industries. Therefore, HEWMS can address important evolving biofuels applications, such as ethanol and other advanced biofuels production. These would be very substantial future markets where HEWMS will have positive cost and greenhouse gas emissions reduction benefits. Specifically, if only 100 million tons of biomass were processed per year, greenhouse gas emissions benefits would be 105 million tons per year.
For further development and successful commercialization, HEWMS will be implemented as a modification to the successfully tested Altex BBADS biomass densification system. By coordinating HEWMS and BBADS, HEWMS can be moved toward commercialization more quickly at a lower cost.

Supplemental Keywords:

biomass, water management, lignocellulosic material, biofuel