Biomass systems

Under low-dose conditions, forest ecosystems act as sinks for atmospheric pollutants and in some instances as sources. As indicated in Chapter 7, the atmosphere, lithosphere, and oceans are involved in cycling carbon, nitrogen, oxygen, sulfur, and other elements through each subsystem with different time scales. Under low-dose conditions, forest and other biomass systems have been utilizing chemical compounds present in the atmosphere and releasing others to the atmosphere for thousands of years. Industrialization has increased the concentrations of NO2, SO2, and CO2 in the "clean background" atmosphere, and certain types of interactions with forest systems can be defined. 

Ibsen, K., Equipment design and cost estimation for small modular biomass systems, synthesis gas cleanup, and oxygen separation equipment, Contract Report NREL/SR-510-39943, NREL Technical Monitor, Section 2, May 2006. 

Tars have a tendency to cling to the filter surface and can undergo subsequent carbonization reactions that lead to fouling and plugging. Even in the absence of further decomposition, tars are difficult to remove from these materials. Examples of barrier filters suitable for biomass systems include rigid, porous-candle, or cross-flow filters constructed of metal or ceramic bag filters constructed of woven material, and packed-bed filters. 

The inherent complexity and chemical diversity of biomass predicts the recovery and purification of proteins from such a source will be an extremely challenging task. We have been studying this problem with a long-term research goal of identifying and establishing experimental conditions which may be applicable for protein purification from all biomass systems. 

There is a large biomass resource available to Canada in the forest. On a per capita basis Canada could well have the greatest contribution of biomass energy of any country, yet the present per capita consumption of energy is already beyond the capability of the present biomass system to satisfy the total demand. 

The basic advantage of the suspended biofilm membrane reactors over the suspended biomass system (either with dispersed cells or with floes) is that the former are able to retain much more biomass [22]. It substantially reduces the biomass wash out and allows a more stable operation with higher biomass concentration. A moving-bed-biofilm membrane reactor is illustrated in Figure 14.5. The biomass is immobilized inside and outside of the fluidized particles. The structure of the biofilm continuously... 

Forsberg, C. (2008), Meeting US Liquid Transport Fuel Needs with a Nuclear Hydrogen Biomass System , International Journal of Hydrogen Energy (2008), doi 10.1016/j.ijhydene.2008.07.110. 

Bioreactors employing plant cell cultures have use in chemicals production systems and in micropropagation (biomass) systems, as well. Factors related to the performance of these reactors from an engineering point of view have been addressed in this paper. Some preliminary data from our laboratory suggest how mass... 

DeLong, M. M. (1995). Economic Development Through Biomass Systems Integration, Vols. 1-4, Northern States Power Company, Minneapolis, MN (NREL/TP-430-20517). National Renewable Energy Laboratory, Golden, CO, December. 

Bema, G. (1998) Integrated Biomass System. Final report, AIR 1-92-8004-IT, European Commission, Luxembourg EUR 17541 EN. 

Tabto VI. RELATIVE ADVANTAGES AND DISADVANTAGES OF AQUATIC PLANT BIOMASS SYSTEMS RELATIVE TO TERRESTRIA PLANTS... 

Ashare, E., et al. "Cost Analysis of Aquatic Biomass Systems" Dynatech R/D Company Cambridge, Mass., 1978. 

Benemann, J.R. Energy from Aquaculture Biomass Systems Fresh and Brackish Water Aquatic Plants Office of Technology Assessment, in press. 

North American Aviation, Inc. A Study of the Use of Biomass Systems in Water Renovation. 1967 Final Report. 

To provide R D program recommendations for the U.S. Department of Energy Fuels from Biomass Systems Branch. 

Conventionally, the overall reactions for biomass conversion have been rationalized based on experimental observations, mainly through identification of the final products. However, the detailed mechanisms need further exploration. In particular, improvement of catalytic processes will depend on a better mechanistic understanding, and this represents a significant challenge due to the complexity of biomass systems. There is increasing recognition that sustainable catalytic processes must avoid the use of precious, scarce or supply-restricted metals. In the near future, this will require extensive research on reactivity of first-row transition metals as well as biochemical approaches. 

Together, these 14 chapters cover some of the most recent and important developments in biomass conversion systems research. We hope the book will serve as a useful guidebook for researchers and industrial practitioners working in biomass systems. 

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