Biomass wheat straw

A report on the continuous flash pyrolysis of biomass at atmospheric pressure to produce Hquids iadicates that pyrolysis temperatures must be optimized to maximize Hquid yields (36). It has been found that a sharp maximum ia the Hquid yields vs temperature curves exist and that the yields drop off sharply on both sides of this maximum. Pure ceUulose has been found to have an optimum temperature for Hquids at 500°C, while the wheat straw and wood species tested have optimum temperatures at 600°C and 500°C, respectively. Organic Hquid yields were of the order of 65 wt % of the dry biomass fed, but contained relatively large quantities of organic acids. 

Potential resources of xylans are by-products produced in forestry and the pulp and paper industries (forest chips, wood meal and shavings), where GX and AGX comprise 25-35% of the biomass as well as annual crops (straw, stalks, husk, hulls, bran, etc.), which consist of 25-50% AX, AGX, GAX, and CHX [4]. New results were reported for xylans isolated from flax fiber [16,68], abaca fiber [69], wheat straw [70,71], sugar beet pulp [21,72], sugarcane bagasse [73], rice straw [74], wheat bran [35,75], and jute bast fiber [18]. Recently, about 39% hemicelluloses were extracted from vetiver grasses [76]. 

Recent studies have proven ethanol to be an ideal liquid fuel for transportation and renewable lignocellulosic biomass to be an attractive feedstock for ethanol fuel production by fermentation (1,2). The major fermentable sugars from hydrolysis of lignocellulosic biomass, such as rice and wheat straw, sugarcane bagasse, corn stover, corn fiber, softwood, hardwood, and grasses, are D-glucose and D-xylose except that softwood... 

Ocio, J. A. and Brookes, P. C. (1990a). An evaluation of methods for measuring the microbial biomass in soils following recent additions of wheat straw and the characterization of the biomass that develops. Soil Biol. Biochem. 22, 685-694. 

Olsson, M. (2006). Wheat Straw and Peat for Fuel Pellets - Organic Compounds From Combustion. Biomass Bioener., 30, 555-564. 

The renewable energy resource biomass also can be used in a gasification process to produce hydrogen fuel. Biomass includes organic materials such as wheat straw, animal wastes, forest residues, and special crops like switchgrass or willow trees that are grown to be used as energy sources. 

The major technical barrier associated with biomass combustion systems is the formation of tenacious deposits on heat transfer surfaces caused by the unique high-temperature chemistry of biomass ash. Many types of biomass used in combustion systems contain alkali metal species sodium, potassium, and calcium. The ash content of woody biomass is quite low and not a problem. The ash content of agricultural residues such as wheat straw, rice straw, com stover, and alfalfa stems can be quite high, on the order of 5 percent or up to 20 percent for rice straw and rice husks. The presence of alkali metals in conjunction with the high silica content of some biomass ashes can lead to molten ash at combustion temperatures.553-658 In some cases, the K, Si, and A1 contents are such that very low melting-point eutectic mixtures can form. The materials can be fluid at combustion temperatures, but form glasslike deposits on colder downstream surfaces such as heat exchanger tubes. 

The prices of some pertinent examples of agriculture-based raw materials (biomass) are compared with oil and coal in Table 8.1. It is obvious that the cheapest source of carbon is agricultural waste, i.e. waste plant biomass such as corn stover, wheat straw and sugar cane bagasse, which consists primarily of lig-nocellulose. 

It has been estimated [3] that enough waste plant biomass is generated in the United States to produce all of the organic chemicals currently manufactured by the US chemical industry and supply a significant fraction of its liquid transportation fuel needs. For example, one ton of wheat straw affords ca. 600 kg of carbohydrates and ca. 200 kg of lignin. The former can be converted, by fermen-... 

The samples used in the study comprised various biomasses and a selection of Danish straws. The analyses of the fiiels used in the study are presented in Tables 1 and 3, and the chemical composition of ash, together with a summary of the thermobalance sintering tests, in Tables 2 and 4. The Danish wheat straw qualities were selected on the basis of growth site, fertilising and weathering conditions [9],... 

Kurkela, E., Laatikainen-Luntama, J., Stihlberg, P. Moilanen, A. (1996). Pressurised fluidised-bed gasification experiments with biomass, peat and coal at VTT in 1991-1994. Part 3. Gasification of Danish wheat straw and coal. Espoo VTT. 41 p. + app. 5 p. (VTT Publications 291). 

Ergudenler A., Ghaly E- (1992) Quality of gas produced from wheat straw in a Dual-Distributor type Fluidised bed Gasifier. Biomass and Bioenergy, 3(6), 419-430. 

A number of biomass fuels and refuse derived fuels (RDF) have been gasified and subsequently combusted in the Vamamo plant. The fuels cover a broad range of nitrogen content, from 0,1% in sawdust to 1% in wheat straw. 

In this work, we have used ash samples form three different agricultural biomass fuels, wheat straw, olive-oil residue, and com cob. Experiments were performed on ash from untreated biomass feedstocks, as well as from biomass samples pretreated according to two different pretreatment methods, i.e., fractionation (Arvelakis ct al., 1996) and leaching (Jenkins et al, 1996 Turn et al, 1997). 

Ergudenler A. and Ghaly A. E., Agglomeration of silica sand in a fluidised bed gasifier operating on wheat straw . Biomass and Bioenergy, 4(1993) 135-147. 

The pyrolysis of wheat straw could be expected to be described by a superposition model, i.e. described by a number of parallel first order reactions, representing the decomposition of the biomass constituents (cellulose, hemicellulose and lignin) [4,5]. In this work, a superposition model has been used, in which the pyrolysis is assumed to be described by N independent first order reactions (for i=l, 2,..., N) ... 

Lignocellulosic biomass refers to plant-derived material such as bagasse, com stover, wheat straw, rice straw, wood chips and switch grass. It is an abundant and renewable resource which is also potentially carbon-neutral and potentially economically viable if appropriate processing methods can be developed to extract and... 

Despite the variety of sources, all lignocellulosic material is composed primarily of cellulose, hemicellulose and lignin [22], Agricultural wastes such as bagasse, com stover and wheat straw are thus a relatively cheap source of these three biopolymers. The major challenge to using lignocellulosic biomass as a feedstock is the development of cost-effective methods to separate, refine and transform it into chemicals and fuels [20],... 

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