Plant residues, utilization

These days, allelopathic plants as catch crops or trap crops found utilization in plant protection of tropical regions against parasitic weeds. They do not eliminate the parasite completely but decrease the seed bank in the soil. Other applications of allelopathy for weed control include the use of plant residues as a natural herbicide agent, e.g., water extracts, pellets, flours, by-products of crop processing, etc. The strategies for use of volatile compounds as soil fumigants are developed. 

There are at present 2 or 3 low Btu gasifier installations at the engineering demonstration phase. Over the next few years these units are expected to become commercially available for deployment, and will be utilized both within the forest industry and at other sites where wood waste and plant residue are available. 

Oil condensed from the released volatiles from the second stage is filtered and catalytically hydrotreated at high pressure to produce a synthetic cmde oil. Medium heat-content gas produced after the removal of H2S and C02 is suitable as clean fuel. The pyrolysis gas produced, however, is insufficient to provide the fuel requirement for the total plant. Residual char, 50—60% of the feed coal, has a heating value and sulfur content about the same as feed coal, and its utilization may thus largely dictate process utility. 

Staman et al. (2001) stated that in order to demonstrate that allelopathic interactions are occurring, one must, among other things, demonstrate that putative phytotoxins move from plant residues on or in the soil, the source, through the bulk soil to the root surface, a sink, by way of the rhizosphere. These authors hypothesized that the incorporation of phytotoxic plant residues into the soil would result in a simultaneous inhibition of seedling growth and a stimulation of the rhizosphere bacterial community that could utilize the putative phytotoxins as a carbon source. If true and consistently expressed, such a relationship would provide a means of establishing the transfer of phytotoxins from residue in the soil to the rhizosphere of a sensitive species under field conditions, presently, direct evidence for such transfer... 

The biggest disadvantage of all humid methods of gas cleaning is the formation of a large amount of liquid residue, which must be utilized or disposed of. If in the general scheme of the cleaning plant in the refinery, there is no plant for utilizing such residues, this method will only lead to transfer of pollutants from gas into water. 

Power generation plants worldwide utilize various types of fuels (Figure 3.1), including low-price fuels to boil water the steam so produced is directed toward a turbine, which turns a generator (International Energy Agency 2008). Solid and liquid fuels like coal and residual fuel oils are used to obtain the required temperatures. Municipal solid waste (MSW) is also used for energy production (Lee et al. 2007). The steam at the low-pressure exit end of the turbine is condensed and... 

Another sector for generation of tertiary bioresources is the maintenance of gardens, other green areas, and special installations with vegetation. In contrast to the secondary maintenance bioresources the plant residues are not genuine and/or often partly degraded before they arrive in a utilization facility. 

Particleboard. Particleboard is prepared using small dried-particles combined with a thermally curable adhesive or other suitable binder and bonded together under high heat and pressure into panels of the desired thickness. The raw materials used to produce particleboard consist of wood wastes from sawmills, primarily from milled or groimd wood chips, sawdust, and planer shaving. In some cases recycled cellulosic materials and plant residues such as wheat straw and bagasse are utilized as fiimish to make particleboard. Most particleboard is formed into flat panels. However, molded and extruded particleboard products such as furniture parts, molded door skins, and molded pallets are also produced. 

Utilizing autoradiography and plant residues labeled with Grossbard (1973a) studied the decomposition of these residues. Also using Waid et aL (1973) used an autoradiographic technique to detect active microbial cells in nature. 

Essentially all of the methane [74-82-8] is removed ia the demethanizer overhead gas product. High recovery of ethane and heavier components as demethanizer bottoms products is commonplace. The work that is generated by expanding the gas ia the turboexpander is utilized to compress the residue gas from the demethanizer after it is warmed by heat exchange with the inlet gas. Recompression and deUvery to a natural gas pipeline is performed downstream of the plant. A propane recovery of 99% can be expected when ethane recoveries are ia excess of 65%. 

In the United States, the largest concentration of atmospheric vanadium occurs over Eastern seaboard cities where residual fuels of high vanadium content from Venezuela are burned ia utility boilers. Coal ash ia the atmosphere also coataias vanadium (36). Ambient air samples from New York and Boston contain as much as 600—1300 ng V/m, whereas air samples from Los Angeles and Honolulu contained 1—12 ng V/m. Adverse pubHc health effects attributable to vanadium ia the ambieat air have aot beea deteroiiaed. lacreased emphasis by iadustry oa controlling all plant emissions may have resulted ia more internal reclamation and recycle of vanadium catalysts. An apparent drop ia consumption of vanadium chemicals ia the United States since 1974 may be attributed, in part, to such reclamation activities. 

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