Economic value of biomass

The economic value of biomass is determined by the revenue from the various products on the market and the production costs (e.g., capital and operation costs) of the various products. In most of the cases products with a relative high market value are associated with high production costs, and vice versa. In addition, also the size of the market is relevant for the economic feasibihty of biorefining. In most of the cases, products with a high market value have a relative small market (e.g., speciality chemicals) and vice versa (e.g., liquid... 

Gasification of coal can produce synthesis gas (syngas) not only from coals having a wide range of heat values but also from low-value carbon feedstocks such as petroleum coke, high-sulfur fuel oil, municipal wastes, and biomass. This flexibility increases the economic value of these resources and lowers costs by providing industry with a broader range of feedstock options. 

The economics of biomass conversion needs to be considered as well, for the production costs of biofuels typically amount to 60-120 per barrel of oil equivalent. Influential factors include the cost of the biomass at the plant gate, the conversion efficiency, the scale of the process and the value of the product (e.g., fuel, electricity or chemicals). 

A thorough analysis of value chains and the development of alternative value chains starting from biomass derived feedstocks, including assessment of the economic viability of the transformation of the chains, is required. This should be followed by the identification of easy entry points for the implementation of novel value chains. Technical key issues are generic methods to cope with the variability of raw materials derived from biomass and higher susceptibility to contamination by microorganisms and suitable catalysts for biorefineries. 

The biorefinery approach is the most sound in terms of truly exploiting the potential of an aquatic biomass, and this concept is now becoming accepted on a worldwide basis. In the biorefinery approach, the economic and energetic value of the biomass is maximized, although it must be emphasized that fluctuations in the prices of fossil carbon (coal, oil, gas) raises uncertainty regarding the opportunity to produce biodiesel from aquatic biomass. For example, when the oil price is below US 120 per barrel it is uneconomic to produce biodiesel in this way. On the other hand, an aquatic biomass demonstrates an excellent potential for use as a source of specialty chemicals, with some components also having added value as animal feeds or fertilizers. 

The cost of transporting wood chips by truck and by pipeline as a water slurry was determined. In a practical application of field delivery by truck of biomass to a pipeline inlet, the pipeline will only be economical at large capacity (>0.5 million dry t/yr for a one-way pipeline, and >1.25 million dry t/yr for a two-way pipeline that returns the carrier fluid to the pipeline inlet), and at medium to long distances (>75 km [one-way] and >470 km [two-way] at a capacity of 2 million dry t/yr). Mixed hardwood and softwood chips in western Canada rise in moisture level from about 50% to 67% when transported in water the loss in lower heating value (LHV) would preclude the use of water slurry pipelines for direct combustion applications. The same chips, when transported in a heavy gas oil, take up as much as 50% oil by weight and result in a fuel that is >30% oil on mass basis and is about two-thirds oil on a thermal basis. Uptake of water by straw during slurry transport is so extreme that it has effectively no LHV. Pipeline-delivered biomass could be used in processes that do not produce contained water as a vapor, such as supercritical water gasification. 

Since, as shown in Fig. 5, changing the moisture level of wood chips from 50% to 67% increases the requirement for field biomass in direct combustion by 78% for a given output of heat and power, it is evident that water-based pipelining of wood chips cannot be economical for direct combustion, because the increase in field harvest cost associated with the higher biomass requirement is larger than any possible transportation cost saving. For straw, so much water is taken up that the LHV is effectively zero pipeline transport of straw to a direct combustion application would destroy the heating value of the fuel. 

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