Bagasse
Encyclopedia
Bagasse is the fibrous matter that remains after sugarcane
Sugarcane
Sugarcane refers to any of six to 37 species of tall perennial grasses of the genus Saccharum . Native to the warm temperate to tropical regions of South Asia, they have stout, jointed, fibrous stalks that are rich in sugar, and measure two to six metres tall...

 or sorghum
Sorghum
Sorghum is a genus of numerous species of grasses, one of which is raised for grain and many of which are used as fodder plants either cultivated or as part of pasture. The plants are cultivated in warmer climates worldwide. Species are native to tropical and subtropical regions of all continents...

 stalks are crushed to extract their juice. It is currently used as a biofuel
Biofuel
Biofuel is a type of fuel whose energy is derived from biological carbon fixation. Biofuels include fuels derived from biomass conversion, as well as solid biomass, liquid fuels and various biogases...

 and as a renewable resource in the manufacture of pulp
Pulp (paper)
Pulp is a lignocellulosic fibrous material prepared by chemically or mechanically separating cellulose fibres from wood, fibre crops or waste paper. Wood pulp is the most common raw material in papermaking.-History:...

 and paper products and building materials.

Agave bagasse is a similar material that consists of the tissue of the blue agave after extraction of the sap.

Production, storage and composition

For each 10 tonnes of sugarcane crushed, a sugar factory produces nearly 3 tonnes of wet bagasse. Since bagasse is a by-product of the cane sugar industry, the quantity of production in each country is in line with the quantity of sugarcane produced.

The high moisture content of bagasse, typically 40 to 50%, is detrimental to its use as a fuel. In general, bagasse is stored prior to further processing. For electricity production, it is stored under moist conditions, and the mild exothermic reaction that results from the degradation of residual sugars dries the bagasse pile slightly. For paper and pulp production, it is normally stored wet in order to assist in removal of the short pith
Pith
Pith, or medulla, is a tissue in the stems of vascular plants. Pith is composed of soft, spongy parenchyma cells, which store and transport nutrients throughout the plant. In eudicots, pith is located in the center of the stem. In monocots, it extends also into flowering stems and roots...

 fibres, which impede the papermaking process, as well as to remove any remaining sugar.

A typical chemical analysis of bagasse might be (on a washed and dried basis):

Cellulose
Cellulose
Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to over ten thousand β linked D-glucose units....

 45–55%

Hemicellulose
Hemicellulose
A hemicellulose is any of several heteropolymers , such as arabinoxylans, present along with cellulose in almost all plant cell walls. While cellulose is crystalline, strong, and resistant to hydrolysis, hemicellulose has a random, amorphous structure with little strength...

 20–25%

Lignin
Lignin
Lignin or lignen is a complex chemical compound most commonly derived from wood, and an integral part of the secondary cell walls of plants and some algae. The term was introduced in 1819 by de Candolle and is derived from the Latin word lignum, meaning wood...

 18–24%

Ash 1–4%

Wax
Wax
thumb|right|[[Cetyl palmitate]], a typical wax ester.Wax refers to a class of chemical compounds that are plastic near ambient temperatures. Characteristically, they melt above 45 °C to give a low viscosity liquid. Waxes are insoluble in water but soluble in organic, nonpolar solvents...

es <1%

Bagasse is an extremely inhomogeneous material comprising around 30-40% of "pith" fibre, which is derived from the core of the plant and is mainly parenchyma
Parenchyma
Parenchyma is a term used to describe a bulk of a substance. It is used in different ways in animals and in plants.The term is New Latin, f. Greek παρέγχυμα - parenkhuma, "visceral flesh", f. παρεγχεῖν - parenkhein, "to pour in" f. para-, "beside" + en-, "in" + khein, "to pour"...

 material, and "bast", "rind", or "stem" fibre, which comprises the balance and is largely derived from sclerenchyma material. These properties make bagasse particularly problematic for paper manufacture and have been the subject of a large body of literature.

Use

Many research efforts have explored using bagasse as a renewable power generation source and for the production of bio-based material
Bio-based material
A bio-based material is simply an engineering material made from substances derived from living matter. These materials are sometimes referred to as biomaterials, but this word also has another meaning. Strictly the definition could include many common materials such as wood and leather, but it...

s.

Fuel

Bagasse is often used as a primary fuel source for sugar mills; when burned in quantity, it produces sufficient heat energy to supply all the needs of a typical sugar mill, with energy to spare. To this end, a secondary use for this waste product is in cogeneration
Cogeneration
Cogeneration is the use of a heat engine or a power station to simultaneously generate both electricity and useful heat....

, the use of a fuel source to provide both heat energy, used in the mill, and electricity, which is typically sold on to the consumer electricity grid.

The resulting CO2 emissions are equal to the amount of CO2 that the sugarcane plant absorbed from the atmosphere during its growing phase, which makes the process of cogeneration greenhouse gas-neutral. Florida Crystals Corporation, one of America's largest sugar companies, owns and operates the largest biomass power plant in North America. The 140 MW facility uses bagasse and urban wood waste as fuel to generate enough energy to power its large milling and refining operations as well as supply enough renewable electricity for nearly 60,000 homes. The facility reduces dependence on oil by more than one million barrels per year.

Ethanol
Ethanol
Ethanol, also called ethyl alcohol, pure alcohol, grain alcohol, or drinking alcohol, is a volatile, flammable, colorless liquid. It is a psychoactive drug and one of the oldest recreational drugs. Best known as the type of alcohol found in alcoholic beverages, it is also used in thermometers, as a...

 produced from the sugar in sugarcane is a popular fuel in Brazil. The cellulose-rich bagasse is now being tested for production of commercial quantities of cellulosic ethanol
Cellulosic ethanol
Cellulosic ethanol is a biofuel produced from wood, grasses, or the non-edible parts of plants.It is a type of biofuel produced from lignocellulose, a structural material that comprises much of the mass of plants. Lignocellulose is composed mainly of cellulose, hemicellulose and lignin...

. Verenium Corporation is building a cellulosic ethanol
Ethanol
Ethanol, also called ethyl alcohol, pure alcohol, grain alcohol, or drinking alcohol, is a volatile, flammable, colorless liquid. It is a psychoactive drug and one of the oldest recreational drugs. Best known as the type of alcohol found in alcoholic beverages, it is also used in thermometers, as a...

 plant based on cellulosic by-products like bagasse in Jennings, Louisiana
Jennings, Louisiana
Jennings is a small city in and the parish seat of Jefferson Davis Parish, Louisiana, United States, near Lake Charles. The population was 10,986 at the 2000 census....

. They are using a biotech approach to improve ethanol production above and beyond the midwest corn-based ethanol production method. This will allow regional cellulosic ethanol production, getting around the problem of ethanol transportation. The Verenium approach will deliver ethanol and E85 fuel to markets in California and the Northeast.

Paper

Around 5–10% of paper production worldwide is produced from agricultural crops, valuing agricultural paper production at between $5 and $10 billion. One of the most notable of these is bagasse. Paper production is the second-largest revenue stream from bagasse; the largest is electricity cogeneration. Using agricultural crops rather than wood does not have the advantage of reducing deforestation, as forests are often burned to allow for the production of agriculture. It is thought that bagasse has the added advantage over other forms of papermaking feedstock in that it requires fewer greenhouse gases to collect, compared to harvesting of wood chips, as the fibre has already been transported to the factory for extracting the sugar. However, there has not been a full lifecycle analysis to support this claim. Due to the ease with which bagasse can be chemically pulped, bagasse requires less bleaching chemicals than wood pulp to achieve a bright, white sheet of paper. The fibers vary in length depending on the country and cane variety but are typically about 1.3 to 1.7 mm long. Bagasse fibers are well suited for tissue
Tissue paper
Tissue paper is a lightweight paper or, light crêpe paper. Tissue can be made both from virgin and recycled paper pulp.-Properties:Key properties are: strength, absorbency, basis weight, thickness , brightness, stretch, appearance and comfort....

, corrugating medium, newsprint
Newsprint
Newsprint is a low-cost, non-archival paper most commonly used to print newspapers, and other publications and advertising material. It usually has an off-white cast and distinctive feel. It is designed for use in printing presses that employ a long web of paper rather than individual sheets of...

, and writing paper
Writing paper
Printing and writing papers are paper grades used for newspapers, magazines, catalogs, books, commercial printing, business forms, stationeries, copying and digital printing. About 1/3 of the total pulp and paper marked is printing and writing papers....

.

Bagasse pulp and paper mills tend to be smaller than wood-based mills, although many world-scale factories exist.
TNPL is the Largest bagasse-based Paper Mill in the world, consuming about one million tones of bagasse every year. By using bagasse as primary raw material, TNPL  preserves over 40,000 acres (160 km2) of forest land from depletion every year

Most chemical bagasse pulp mills concentrate the spent reaction chemicals and combust them to power the paper mills and to recover the reaction chemicals.

Bagasse Foodservice Products

Bagasse is used to make disposable food containers, replacing materials such as styrofoam
Styrofoam
Styrofoam is a trademark of The Dow Chemical Company for closed-cell currently made for thermal insulation and craft applications. In 1941, researchers in Dow's Chemical Physics Lab found a way to make foamed polystyrene...

, which are increasingly regarded as environmentally unacceptable (see Polystyrene#Environmental impact). Bagasse is considered a renewable material because it is the waste material from sugacane, a crop that is harvested annually. In addition, several bagasse products have been certified 100% compostable by the Biodegradable Products Institute. Bagasse products have many qualities that allow them to be an evironmentally friendly substitute without sacrificing quality. These attributes include high water/oil temperature resistance, as well as safe for use in microwave and freezer.

Other Uses

Sugarcane bagasse has recently been used as the primary ingredient in 'Soex' brand Herbal Shisha. The shisha is sold as 100% tobacco-free, nicotine-free, and tar-free. The health effects of smoking sugarcane bagasse have not been studied.

Bagasse is also made into cattle feed whereby it is mixed with molasses. The resulting byproduct has been marketed in Australia as "cow candy".

Efforts were made in late 1998 to use bagasse as a sorbent material to clean up oil spills. Dr. Gary Breitenbeck, a soil microbiology and environmental researcher in the agronomy department of the LSU Agricultural Center, used milled bagasse to soak up spilled oil and created an environment that sustains the bacteria that digest the goo using ammonia. "Breitenbeck's process puts the bagasse, along with ammonia and air, in a reactor and pumps up the pressure to 1,000 pounds per square inch [equivalent to 6894.757 kilopascals ]. The high pressure drives the ammonia into the fibers and produces nitrogen compounds the microbes use to convert the hydrocarbons into humic material."

Bagasse is being used as a compost feedstock in post-earthquake Haiti where humanure toilets are being implemented. It is used as a cover material in toilet systems developed by SOIL and by GiveLove.org. The "compost sanitation" systems are based on the work of Joseph Jenkins and his book, the Humanure Handbook - A Guide to Composting Human Manure There are videos of Haitian Compost Sanitation that can be watched online free.

Health impact

Bagasse factories have historically had harsh working environments due to the process of milling the pulp. Factory workers have reported bleeding hands and arms. Workers must wear masks to prevent breathing in pulp fibres.

Workplace exposure to dusts from the processing of bagasse can cause the chronic lung condition pulmonary fibrosis
Pulmonary fibrosis
Pulmonary fibrosis is the formation or development of excess fibrous connective tissue in the lungs. It is also described as "scarring of the lung".-Symptoms:Symptoms of pulmonary fibrosis are mainly:...

, more specifically referred to as "bagassosis".

Further reading

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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