Biomass production inputs

Microbial processes in terms of sludge (biomass) production, BOD and nutrient removal have been focused on when dealing with biological wastewater treatment. Therefore, and because the sewer is the system for input to the wastewater treatment plant, there is a basis as well as a perspective to establish a process concept for the sewer that can be integrated with the activated sludge processes. 

Soil-related data (HM and BC content in soil parent materials) were included in calculations to account the values of HM weathering. Also we considered the influence of soil types on forest biomass productivity. Runoff data (at scale 0.5 x 0.50 were directly used to get input data on drainage water fluxes, Qie. Forest-type-related data (wood biomass growth and HM content in wood biomass) inserted into our database were subdivided depending on either coniferous, deciduous or mixed forests. 

Fuel biomass production, though, requires a commitment of land, a consistent supply of water, energy input to develop and maintain, and can directly compete with food production. 

The bacterial population faced with the "autumn-input" was derived from an anoxic population (fermentative bacteria, sulfate reducers) which prevailed during summer stagnation. Within this population the input of freshly produced organic material caused a drastic shift. Bacteria primarily reacted with a strong increase in cell volume (biomass production). Deviating from its "normal" distribution (cf. above), the size spectrum was dominated by medium and large-size cells. Following the final breakdown and sedimentation of the autumn phytoplankton bloom, the bacteria subsequently responded with cell division (increase in cell number). 

Normal weathering processes that occur in nutritious soils release nutrients, but they are often not available at rates that promote maximum biomass yields. Fertilization is usually necessary to maximize yields. Since nitrogenous fertilizers are currently manufactured from fossil fuels, mainly natural gas, and since fertilizer needs are usually the most energy intensive of all the inputs in a biomass production system, a careful analysis of the integrated biomass production-conversion system is necessary to ensure that net energy production is positive. Trade-offs between synfuel outputs, nonsolar energy inputs. 

Fermentation biomass productivities usually range from 2 to 5 g/(l h). This represents an ojq gen demand in the range of 1.5 to 4 g 0/(1 h). In a 5(X)-m fermenter, this means achievement of a volumetric oxygen transfer coefficient in the range of250 to 400 h . Such oxygen-transfer capabilities can be achieved with aeration rates of the order of 0.5 WM (volume of air at STP/volume of broth) and mechanical agitation power inputs of 2.4 to 3.2 Kw/m (1.2 to 1.6 HP/ 100 gal). 

The overriding importance of carbon inputs for microbial and organic phosphorus was also demonstrated in agroforestry trials in Kenya, in which fallow biomass production did not respond to phosphorus fertilization, and increases in organic and microbial phosphorus were similar between unfertilized and fertilized systems (Smestad et al., 2002 Bunemann et al., 2004). Thus, increased inputs of organic materials have the potential to enhance levels of soil organic phosphorus. 

Published production costs for both herbaceous and woody biomass show broad variations that are both understandable and inevitable (3.6,7., 58). A given contractor will want to present his speciality crop in the best possible light relative to the dollar inputs needed to obtain a million Btu s in biomass form. This topic has been reviewed in detail ( ). It was concluded that most biomass researchers greatly underestimate the cost of biomass production, excluding from their calculations significant indirect costs, long-term repercussions on ecosystem resources, future competition for land and water, and both the cost and efficiency of biomass conversion systems. 

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