There are Bioenergy and Product Alternatives towards the use of Manures versus its use as a Fertilizer

Manure from livestock such as cattle has been used in the past as a natural based fertilizer. However, concerns related to health and environmental issues have made the use of manure as a direct fertilizer application a more difficult option. There are issues like possible disease transfer from harmful bacteria that culminate in the manure such as E. Coli & Salmonella. Pollution run-off and noxious or odorous compounds are also concerns. The amount of manure use on land and its timing of application are very important considerations. Too much application can cause nitrogen and phosphorus based non-point source pollution runoff. The majority of livestock feedlots or farms are small or modest in size and are scattered across the country unless they are feedlots that are direct sellers to meat packing facilities [2. MacDonald et al 1999 - USDA] -- (Link to Publication). Cattle and hogs are raised in several different facilities while chickens are raised at a location that is also nearby to a meat processing facility. Poultry farms average many thousands of broilers raised per farm each year. Dairy farms vary in herd size averaging 120 cattle per lot in 2006, most farms are midsize but many large dairy farms exist that house thousands of cattle at one time [3. MacDonald et al 2007] -- (Link to Publication). Atmospheric gases from the breakdown of manure can accumulate in higher concentrations to become an odor nuissance such as the case with ammonia or hydrogen sulfide. It can be difficult to find enough direct land fertilizer application uses within a short distance as higher amounts of manure collect within larger, confined feedlot areas. According to the USDA Billion Ton Study the number and size of confined feeding lots has increased especially with poultry products and they also recommend that manure be processed or used on the farm or within a short distance of where it was generated. Greater costs are incurred if manure is utilized at greater distances from a feedlot facility due also to transportation and storage.

There are many other options for using manure other than direct land application. Even direct use as fertilizer is an allowable method if it is well regulated as is the case with Organic Farming Operations. Its application must meet certain criteria. For example, manure must be applied on a plot of land for a duration of three years and also meet soil testing standards before crops can be sold as an organic commodity [Organic Farming Doc] -- Link to Documentation). Manure could also be mixed with other organic types of wastes to become a usable compost. Even in these situations, care must be taken with handling and storage of manure. Manure can still be effectively used for nutrient value if stored or used in well managed lagoon pools. These methods also reduce pathogens and odors eminating from it. Manure has been finding increasing applications in the bioenergy / biomaterials sectors of industry. There are a slew of possible applications for the use of manure as applied towards bioenergy as it can be converted into a biogas or biofuel using methods such as Anaerobic Digestion. In fact, more usable types of biofuels are produced from the combination of manure and an energy crop such as grass instead of just one of these sources used alone. These methods can also be applied towards the production of biomaterials such as bioplastic type compounds called PHAs (Polyhydroxyalkanoates) [Gungor et al 2009]. Conversion of manure into biofuel or biomaterials has great potential since less land requirements are needed as opposed to direct land application. These facilities can also be located nearby livestock or poultry feedlots and dairy facilities. These production processes are oftentimes well regulated and should not be an environmental or health concern as well as being a storage or transportation liability. It may also be possible to recycle the biomass (microbial, fungi or algae) into usable fertilizer material once it has already been used for bioenergy purposes.

REFERENCES

1. "Consolidation in U.S. Meatpacking - Developments in Meat Consumption and Livestock Production", Agricultural Economics Report No AER785 [1999], MacDonald J., Ollinger M., Nelson K., Handy C.

2. "Profits, Costs and the Changing Structure of Dairy Farming - Changes in Size and Location of U.S. Dairy Farms", USDA Economic Research Service Publication [2007], MacDonald J., O'Donoghue E., McBride W., Nehring R., Sandretto C., Mosheim R.

3. "Biogas Production : Current State and Perspectives", Applied Microbiology and Biotechnology Vol 85 pgs 849-860 [2010], Weiland P.

4. "Prefermentation of Liquid Dairy Manure to Support Biological Nutrient Removal", Bioresource Technology Vol 100 pgs 2124-2129 [2009], Gungor K., Muftugil M., Ogejo J.A., Knowlton K., Love N.

KEYWORDS: Biogas, Anaerobic Digesters, Manure fertilizer use, Pathogens from manure, Composting, Non-point source pollution, Lagoon pools, Alternative manure uses, Bioelectricity from manure, PHA production, Poultry - Swine - Cattle - Dairy Manures, Odor control of manure

Desert Arid Energy Type Crops Prove good to be Drought and/or Salinity Tolerant

There are a variety of cultivated crops that could grow well in arid, desert lands and climates that could become bioenergy crops and also serve to make other products such as alternative feed for animals. There are three crops that are worthy of discussion due to their plant growth adaptibility to desert conditions and their possible use as alternative fuel or energy. Salicornia, Sweet Sorghum and Amaranth to some degree are well suited to desert environments in that some of them have special growth characteristics such as low water consumption or drought tolerance and are also well suited to high salinity water and soil conditions. The majority of these plants actually grow better in more favorable ecosystems and climate but have proven to have adapted well to desert soil, water and climate conditions. Growing bioenergy crops on marginal use lands is a hot topic that should be continued to be discussed in future generations. For example, another great bioenergy crop that can grow well in semi-arid tropical like areas is Jatropha which can be converted into biodiesel or jet fuel. The more promising of these three crops is Sweet Sorghum. It is a similar energy crop to sugarcane, in that the sugars that reside in the plant can be squeezed out of the stalk and then further fermented into ethanol. The cultivation of Sweet Sorghum into ethanol is promoted by organizations such as the Sweet Sorghum Ethanol Association. Sweet Sorghum is already being cultivated in Arizona on marginal lands for the purpose of production into ethanol. As far as water requirements, Sweet Sorghum has proven superior in water use efficiency compared to other sugar or ethanol producing crops which include corn, sugarcane and sugarbeets. Sweet Sorghum has been shown to require half of what sugarbeets need for crop production and one fourth of what sugarcane requires for water usage [ 1. Prasad et al 2007 ]. Other advantages of using Sweet Sorghum in desert environments is that it is an ideal crop that can be used on fallow land or in other words it could be used as a rotation crop on farm land that would not be able to support another type of crop due to its soil conditions. Sweet Sorghum also grows much more rapidly (ie has a shorter growth cycle) than both sugarcane or sugarbeets [Same Reference as above mentioned]. It also requires less amount of soil nitrogen for its cultivation.

Salicornia is another salt tolerant or halophyte energy crop that is beginning to gain more interest as an energy crop. Salicornia, like Jatropha previously mentioned, are one of the oilseed crops being considered to produce bio-derived jet fuel. One project called
The Sustainable Bioenergy Research Project accomplishes to produce jet fuel from Salicornia that is grown from seawater based fish farm waste effluent. Salicornia is also known as a very healthy plant due to its high protein and salt content. It contains around 30 % protein content and has a variety of healthy salts that can be sundried and used in foods. Salicornia has been known to have pharmalogical value with special medicinal properties. Other plant properties also make it an ideal candidate for other sustainable materials, alternative animal feed and soil remediation projects. Salicornia is so salt tolerant that it can be directly irrigated with seawater itself, which has been done in past research work [ 2. Glenn et al 1997 ]. It is therefore ideal to use with saline types of irrigation water such as brackish water since it can tolerate salinity levels (NaCl) of around 1 mol per kg of soil. Amaranth is another plant that grows in a variety of climates and conditions. There are many species or varieties of it, but it is known throughout the world to be a very healthy plant. The leaves can be consumed by humans or livestock, the plant contains grains that can be converted into a type of bread or also used in fermentation to produce alcohol. The bread made from amaranth is beneficial to people who require gluten free bread with a lot of other health benefits. The protein content of amaranth is also high for a plant source, being around 15 percent. It also contains amino acids that aren't present in other plant sources. As mentioned before, Amaranth provides grain meal that can be fermented by a variety of microorganisms, one type named Rhizopus oryzae can produce ethanol plus other organic compounds from amaranth [ 3. Bramorski et al 1998 ]. Certain species of Amaranth are known to grow quite well in dry, arid desert lands such as Palmer Amaranth. This type of Amaranth uses water very efficiently and has good drought tolerance. Overall, there are many species of plants that could grow well on marginal desert lands
that could provide both fuel, energy and/or food. These three plants have already been experimented with and have proven good candidates for desert crops due to salinity and drought tolerance.

REFERENCES

1. "Ethanol Production from Sweet Sorghum Syrup for Utilization as Automotive Fuel in India", Energy and Fuels Vol 21 pgs 2415-2420 [2007] by S.Prasad, A.Singh, N.Jain, HC Joshi

2. "Water Requirements for Cultivating Salicornia Bigelovii Torr. with Seawater on Sand in a Coastal Desert Environment", Journal of Arid Environments Vol 36 pgs 711-730 [1997] by E.Glenn, S.Miyamoto, D.Moore, J.Brown, TC Thompson, P.Brown

3. "Production of Volatile Compounds by the Edible Fungus Rhizopus Oryzae during Solid State Cultivation of Tropical Agro-Industrial Substrates", Biotechnology Letters Vol 20 No 4 pgs 359-362 [1998] by A. Bramorski, P.Christen, M.Ramirez, CR Soccol, S. Revah

KEYWORDS: Energy and Food Crops, Desert Marginal Lands, Fallow Land, Palmer Amaranth, Gluten free grains, Salicornia, Brackish Water, Plant drought tolerance, Plant Salinity tolerance, Ethanol Production from Sweet Sorghum, Water Usage from Arid Desert Plants, Healthy Desert Plants, Desert Plants for Animal Feed

Photos taken from US Bureau of Land Management & NASA photo archives

Amaranth Biology Chemistry and Technology

Cover Crops can be effective on Farms or Orchards for Soil Reconditioning, Pest Protection & Other Reasons

There are some advantages for employing the use of cover crops in agriculture. Cover crops used to recondition soil are one of the primary reasons for its implementation. These types of crops enhance soil structure, moisture content, promotes soil nutrition and helps to prevent soil erosion as well. These properties are imparted to the soil when the crop is used as a mulch. This usually happens when the crop is mowed or harvested and the residual is left as fallow afterwards. In essence, cover crops can serve as a type of 'rotation crop' when the extended use of a primary crop tends to have the effect of depleting nutrients or soil condition. These soil properties can be restored through the use of cover crops. The soil reconditioning process happens as the crop is plowed and a certain amount is left on the ground to become a mulch later on. Cover crops are seeded varieties such as clover or various grass types. It is recommended that a dense cover crop be used to establish a mulch for the above stated reasons. In addition, a dense cover crop can also prevent the outgrowth of weeds. If the crop is dense enough, it could also serve as an energy crop such as those used to help produce biofuel or bioelectricity. For example, the use of Anaerobic Digestors could be a viable way to produce combined heat and power (CHP) on farms using cover crops such as grasses. The biogas made from an anaerobic digestor can serve as a natural gas source that can be used for either boilers or generators for either electricity, heat or both. The effectiveness of a cover crop can be related to how dense or thick it becomes.

Two measureable indicators of crop density are crop height and amount of ground cover (percent vegetation cover).In a past study used on vineyards, over 30 types of different cover crops were measured for their plant height and vegetation cover.The results of the study showed that around half of the crops had plant heights from 18 - 36 inches and many also had at least 70 % vegetation cover [ 1. Bugg 1996 ]. Cover crops also have the possible use in home gardening. The ability to convert cover crops into mulch material can be applied later on as a compost for the garden. The crop can also be used directly to improve soil conditions due to a variety of reasons. These plants promote the deposition of carbohydrate compounds near the roots from microorganisms, the roots also form an underground network the may allow for future plants to follow known as biodrilling [ 2. Pleasant 2009 ]. The use of cover crops also serves the purpose of pest protection, especially for citrus orchard, nut or vineyard crops. For example, the use of cover crops were employed
for the control of aphids that were comprimising specific pecan orchards. Many aphids in these types of orchards are resistant to insecticides to a specific type of cover crop was grown to help halt the growth of aphids by providing a habitat for ladybugs that feed on aphids [ 3. Bugg et al 1993 ]. Cover crops may not always be effective in eliminating pests, due to various factors that are not as controllable or if the crop is mismanaged. Overall, cover crops can be utilized by various types of farms, orchards or home gardening, which may be able to serve several functions at one time such as soil nutrition, prevent erosion, become an energy crop, and control weeds or insect pests.

REFERENCES

1. "Comparison of 32 Cover Crops in an Organic Vineyard on the North Coast of California", Biological Agriculture and Horticulture Vol 13 pgs 63-81 [1996] by R. Bugg, G. McGourty, M. Sarrantonio, W.T. Lanini, R. Bartolucci

2. "Cover Crops: Options, Tips and Advantages for the Home Garden" - Mother Earth News - Oct/Nov 2009 by Barbara Pleasant

3. "Sesbania exaltata Cory as a Warm Season Cover Crop in Pecan Orchards: Effects on Aphidophagous Coccinellidae and Pecan Aphids", Biological Agriculture and Horticulture Vol 9 pgs 215-229 by R. Bugg and J. Dutcher

Photos taken from the Picasa Web Album

KEYWORDS: Natural Pest Protection, Cover Crops for Vineyards & Citrus Orchards, Cover Crop Density and Height, Rotation Crops, Fallow, Reconditioning Soil, Cover Crops for Bioenergy, Preventing Soil Erosion, Mulches, Composts, Soil Nutrition, Grass & Clover Cover Crop Plants, Natural Weed Control

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Biofuel vs Bioelectricity : Grasses mostly used for Biofuel Production, Bioelectricity for Biorefineries and Possible CHP on Farms

It is estimated that millions of acres will be set aside for the purpose of growing energy crops such as switchgrass in future years. Debates are common as to whether it would be more efficient to use switchgrass to produce electrical power (bioelectricity) versus it's use in producing cellulosic based ethanol for vehicles. Several factors should determine the use of grasses for bioenergy purposes. One of the most important factors, which many scientists agree upon, is the location of the bioenergy farms in relation to the nearest Biomass Conversion Facility (BCM). In fact the USDA offers a Biomass Crop Assistance Program for farmers that intend to grow, harvest, collect and transport bioenergy crops to selected BCM's. The more common Biomass Conversion Facilities most likely will be ethanol biorefineries. Since many BCM's will have a large manufacturing capability, the most common application for bioelectrical power - should be for biorefineries. Thermochemical manufacturing processes common to an Integrated Biorefinery should allow for ample sized power plants to be built along with the refinery, which would also use biomass (ie grass) as a (shared) power source. If the biorefinery is large enough, it may produce ample amounts of electrical power. For example, a Biomass operated Integrated Gasification Combined Cycle (BIGCC) power plant that can produce at least 100 MW of electrical power can also provide additional heating needs for ethanol processing and also put back a net of around 20 MW of electricity back into the power grid for an estimated 40 million gallon per year ethanol capacity manufacturing plant [1. De Kam et al 2009].

Switchgrass also has the potential to produce an array of different chemicals, other than ethanol, such as mixed alcohols and organic acids. This allows different types of biorefineries to coexist using the same biomass source. The manufacture of these kinds of chemicals also allow for the production of hydrogen which would be used to make electrical fuel cell power. A power plant such as an IGCC is designed to operate on a number of different fossil fuel and/or biomass sources. In the near future, ethanol biorefineries based on corn should be retrofitted to allow the production of cellulosic ethanol from grasses. A larger amount of ethanol should be produced from switchgrass versus corn or sugarcane in the USA. Several years ago a DOE study determined that ethanol made from grasses are more efficient to produce than using corn and should produce enough ethanol to help satisfy vehicle fuel demand. This is no small task, since it is estimated that 1 ton of grass produces around 80 gallons of ethanol. It was then estimated that 30 % of petroleum used for gasoline could be displaced at 2004 consumption levels if there were around 600 cellulosic ethanol biorefineries that produced around 100 million gallons of ethanol per year [2. Houghton, Weatherwax & Ferrell 2005] -- (Link to Publication). In summary, grasses most likely will be used to produce electrical power and biofuels/chemicals simultaneously. Switchgrass could also be used on local farms to help produce further electrical power and biogas. The use of Anaerobic Digesters are commonly used in farms in Europe and are significant in use since they are another source of natural gas that can be used for Combined Heating and electrical Power (CHP). In 2007, 6 million tons of oil equivalents (called Mtoe) - as related to overall power generation, was produced from biogas in Europe with Germany being the largest energy biogas producer with the thousands of farms implementing biogas digester units [3. Weiland 2010].

REFERENCES

1. "Biomass Integrated Gasification Combined Cycle for Heat and Power at Ethanol Plants", Energy Conversion and Management vol 50 no 7 pg 1682-1690 [2009], De Kam MJ, Morey RV, Tiffany DG

2. "Breaking the Biological Barriers to Cellulosic Ethanol : A Joint Research Agenda - A Research Roadmap from the Biomass to Biofuels Workshop Sponsored by the US Department of Energy", Office of Energy Efficiency and Renewable Energy, Office of the Biomass Program, December 7-9 2005, Houghton J., Weatherwax S., Ferrell J.

3. "Biogas Production : Current State and Perspectives", Applied Microbiology and Biotechnology Vol 85 pgs 849-860 [2010], Weiland P.

Photos taken from NREL (Department of Energy) Photographic Information Exchange Archive

KEYWORDS: Cellulosic Ethanol, Anaerobic Digerstors, Integrated Gasification Combined Cycle Power Plants, Biogasifiers, Biorefineries, Biomass Conversion Facilities, Biogas, Power Cogeneration, Switchgrass, Petroleum Displacement

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