As mentioned above, abaca fiber is considered as the strongest natural fiber and is obtained from leaves (petioles) which are composed of elongated and slim cells (Umali and Brewbaker 1956). Classified as a hard fiber like coir, sisal, and hene — quin, it is highly prized for its exceptional mechanical (tensile) strength, flexibility, underwater durability, buoyancy, and long fiber length. These properties are due to its high Runkel ratio, i. e., the ratio of two times the fiber cell wall thickness over the fiber cell lumen width. It has been found that the fiber has higher tensile strength than its synthetic counterparts like nylon and rayon and that it is rotting resistant with its specific flexural strength almost equal to glass fiber (Moreno 2001; Bledzki et al. 2008). Moreover the lustrous and colored nature of the fiber makes it a pre­ferred natural fiber. Chemically the abaca fiber is composed of cellulose, pectin, and lignin of which the lignin content is as high as 15 % in addition to significant quanti­ties of ketones, triglycerides, o’-hydroxy-fatty acids (C22-C28), monoglycerides, fatty alcohols, and esterified derivatives of p-hydroxycinnamyl acids (ferulic acid;

4- hydroxy-3-methoxycinnamic acid and p-coumaric acid; 4-hydroxycinnamic acid) containing long-chain alcohols (C20-C28). It has also been found to contain diglyc­erides, steroid hydrocarbons, R-hydroxy-fatty acids, sterol esters, and glycosides in minor quantities (del Rfo et al. 2004; del Rfo and Gutierrez 2006). The excellent tensile strength and exceptional under water durability of abaca fibers has led to their usage in the production of many useful industrial and domestic products. The abaca fiber is used for making ships’ ropes, fishing lines, and fishing nets. It also finds their usage in the production of power transmission ropes as well as in well­drilling cables besides being used for production of cordage for naval and marine vessels. The durability and flexibility of abaca ropes is evident from the fact that a 1 in. (2.5 cm) abaca rope requires at least 4 metric tons (8,800 lb) to get broken (Borneman and John 1997). Moreover, the high-quality fiber obtained from abaca provides an excellent material for paper and pulp industry where it is processed into a variety of paper products like bank notes, security papers, cigarette papers, and filter papers. In textile industry, it is used in the manufacturing of bags, table mats, carpets, furniture fillings, and sausage casings besides being used in the production of lightweight but strong fabrics (from inner fibers without spinning) for hats, gar­ments, and shoes. The finest quality of abaca is Lupis and Sinamay. It has been estimated that the global consumption of abaca fiber accounts for about 80 % in the production of speciality paper products and about 14 % in cordage products while the remaining 6 % in other usages. The applications of abaca fibers can be summa­rized under the following headings (FIDA 2009; Moreno and Protacio 2012):

1. Paper andpulp industry: Filter paper, Cigarette paper, sausage skin, base paper, currency paper, envelopes, book binders, parchment paper, special art paper, adhesive tape paper, lens, vacuum cleaner bag, electrolytic condenser paper, high grade decorative paper, time cards, optical lens wiper, X-ray negative, oil filter, etc. hand-made paper like sheets, multi-purpose cards, balls, decorative items (flowers, photo frames, table clock, and lamp shades)

2. Fabrics and fiber crafts; bags, rugs, carpets, wallets/purses, placemats, door mats, fishing nets, special fabrics like Sinamay, dagmay, and pinukpok in addi­tion to coasters, wallpapers and baskets, some non-woven fabrics like diapers, gowns, etc.

3. Furnishing and household construction items: Furniture fillings, carpets, rugs, and mats. Tiles for roofs and floor, hollow blocks, fiber boards, etc.

4. Fuel: Musafel

5. Miscellaneous applications: Insulators for wires and cables, components of automobiles (particularly in reinforced form), preparation of wigs

The modern technology involves the use of abaca-reinforced polymers to make them more applicable for various purposes. The main focus is the use of thermoset­ting or thermoplastic matrices like polyesters or polypropylene (Shibata et al. 2002, 2003; Ochi 2006; Teramoto et al. 2004; Bledzki et al. 2007; Hadi et al. 2011) which led to the use of abaca fibers (reinforced) in under floor protection or passenger cars. This application involves a combination of abaca-reinforced polypropylene thermo­plastic and the technique has been patented by Daimler Chrysler’s researchers (Bledzki et al. 2006) and the manufacturing process has been initiated by Rieter Automotive, Switzerland. The experimental analysis of abaca-reinforced polypro­pylene polymer at various fiber lengths employing different methodologies (mixer — injection molding, mixer-compression, and direct compression process) has also revealed that increase in fiber length leads to an increase in the tensile or flexural properties with the effective method of reinforcement being mixer-injection pro­cess. Not only abaca, but the fibers obtained from other related members like Musa acuminate or Musa sapientum have been used to reinforce polypropylene to yield a valuable composite fiber (Faria et al. 2006; Bledzki et al. 2008). It has been sug­gested that the increases or enhancement of the durability or tensile strength of composite fibers is due to the changes in the Melt Flow Index (MFI) which can be altered by changing the level of three important variables like abaca fiber (length and composition), maliec anhydride (concentration), and the impact modifier (Hadi et al. 2011). The use of these natural fiber-reinforced green composites offers many advantages over the synthetic counterparts like dependency on renewable raw mate­rial, low production cost, specific mechanical strength, energy-efficient manufactur­ing, eco-friendly (low CO2 emissions), and more importantly biodegradability (Cao et al. 2006; Pervaiz and Sain 2003). The abaca fiber has been used to reinforce furan resin (a condensate of furfuryl alcohol produced from agricultural residues like corn cobs or rice hulls) to produce a green composite. The furan resin, being resistant to many acids, alkalis, or solvents, on reinforcing with cellulosic abaca fiber therefore provides an excellent and eco-friendly material for various industrial applications (Tumolva et al. 2009). It has been reported that the abaca fiber-reinforced PP (poly­propylene) composite has high tensile strength, high flexural strength, and good acoustic resistance besides being resistant to moulds, rot or UV damage and cost — effective (Proemper 2004). Moreover, comparison of abaca-reinforced PP compos­ite with other natural fiber-reinforced composites likes jute-PP composite and flax-PP composite has revealed its superior flexural strength and damping properties compared to other composites despite the fact that jute-reinforced PP composite showed higher tensile strength. Furthermore, the use of coupling agent (MAH-PP; maliec anhydride) has been found to significantly improve the tensile as well as flexural strength of abaca-PP composite (Bledzki et al. 2007). Similar investigations on the improvement in tensile strength and water absorption capacity of abaca — reinforced epoxy composites have also been made where the results have confirmed the efficacy of plasma treatment over conventional sodium hydroxide treatment. Plasma treatment exposure for 2.5 min has been found to result in 92.9 % improve­ment in tensile strength and reduction in water absorption capacity of the fiber epoxy-composite and has been attributed to increase in compatibility between abaca fiber and the epoxy matrix (Paglicawan et al. 2013) . Moreover, the heat-treated abaca-reinforced starch based biodegradable resin has also been prepared whose tensile strength has been found to be comparable to glass fiber-reinforced plastics (Takagi 2011). Abaca fibers are also blended with metallic threads and polyester to put them in multiple uses (FIDA 2012).

Owing to large hollow structure and waxy surface, kapok fiber shows the hydrophobic- oleophilic characteristics. The higher surface tension (7.2 x 10-4 N cm-1 at 20 °C against air) will drive out the water droplets, leading the surface of kapok fiber can­not get wet with the water droplets (Chung et al. 2008), making this fiber show poor affinity to hydrophilic coloring agents or dyes. For kapok fiber, the dyeing effi­ciency is relatively low, and the dyeing property of kapok fiber is worse than that of cotton fiber (Lou 2011). Pretreatment of kapok fiber is thus important to enhance the dyeing property of this fiber, but up to now, no mature processing or pretreat­ment techniques have been established except for the mercerization. Compared with cotton fiber, the alkali resistance of kapok fiber is rather poor, and accordingly, mild alkali treatment conditions are generally expected for kapok fiber in dyeing and finishing processes.

The experiment conducted in the southeastern part of Brazil revealed that macro­fauna of soil is affected by litter layer maintenance in management of unburned sugarcane in both quality and diversity. A comparison was carried out of macro­fauna between adjacent areas with a history of long-term preharvest burning; but harvested without burning for a time span of 4 years and a native forest; sugarcane cropped area for 50 years with burning preharvesting. This comparison showed that a significant reduction was observed in the number of individuals per hectare along with diversification by sugarcane burned for 50 years. Approximately 75 % of indi­viduals comprised sugarcane parasites such as Coleoptera larvae in the system of burned sugarcane (Leal et al. 2013). A significant rise, as compared to the native forest, in the levels of numbers of individuals was observed after 4 years of harvest­ing without burning. Ants and earthworms are the most benefited individuals from the change due to burning. It maintains a litter layer in the soil. After conducting a long-term straw maintenance, an increase of up to 3-4 times in the population of earthworm was observed, compared to the burned sites, in the Australian field experiments (Wood 1991). Commination and incorporation of litter are the few ser­vices that were provided by invertebrates of soil. Along with this, some other ser­vices include structural porosity building and maintenance, soil aggregation through burrowing, activities involving casting and nesting, and microbial activities and communities (Leal et al. 2013).

It has been studied that significant straw amount on the ground can help in the creation of ideal microclimate, in the system of unburned cane harvest, mainly involving humidity and temperature, for weed and pest development and also infes­tation by diseases. An increased importance is given to pests, weeds, and other diseases in the fields of sugarcane. This is due to damage caused by tillers, leaves, stalks, stalk base, and root systems. In addition, several other larger infestations also occur in older sugarcane generally (Hassuani et al. 2005).

A large number of insect species are involved in the sugarcane pest infestations. This infestation is dependent on time of the year as well as the region which can lead to serious economic damage. Sugarcane also provides sheltering for a large number of insect species such as arthropods and other microorganisms that are important in biological control of pests or involved in assistance of soil decomposi­tion of organic substances (Hassuani et al. 2005). An increase in the insect species of froghopper, Mahanarva fimbriolata and Diatraea saccharalis (Lepidoptera: Pyralidae), is associated with the harvesting of unburned cane. This gives rise to a technical challenge that needs to be solved in areas of sugarcane without burning. The sugarcane borer, D. saccharalis, infestation shows variable results independent of harvesting method. A serious problem is indicated by froghopper, M. fimbriolata, in harvesting of unburned cane demanding control method adoption. The entomo — pathogenic fungus Metarhizium anisopliae indicated a high control in the efficiency at a reduced cost with no harmful effect on the environment. As far as weed infesta­tion is concerned, chemical as well as biological changes may be caused by mulch in the soil. This may lead to weed suppression of Brachiaria plantaginea, Digitaria horizontalis, Panicum maximum. and Brachiaria decumbens. There are several species that are not affected by straw presence. Allelopathic compounds are released and this release is attributed by effect of mulch on the control of weed. Other effects attributed by mulch include physical effects including filtering and light wave­length and maintenance of temperature with minor fluctuations (Leal et al. 2013). Some of the weed infestation may be controlled by mulch straw left on the ground, whereas it is not enough for controlling others.

13.2.1 Internal and External Factors Required for Growth of Algal Biomass

13.2.1.1 Water

Being photosynthetic organisms, algae have comparatively simple requirements for growth. Water, containing the accurate amounts of salts and minerals, is a particu­larly essential component needed for algal cultivation. Based on the need for water, algae are basically categorized into aquatic or semiaquatic species. The standard quantity of water required for effective farming of aquatic algae is approximately 1.5 L/ha. This figure is valid considering the fact that growth occurs in an open pond and roughly 7-11 million liters of water is evaporated from that region annually. Algal production can be linked to the remediation of wastewater from both domes­tic and industrial sources. The wastewater, containing the essential elements, can be directly supplied to the algal culture. This allows nourishment of algae while simul­taneously treating wastewater.

13.2.1.2 Carbon

Algae require very high amount of carbon for efficient growth. Procuring carbon for algal growth costs up to 60 % of the total nutrients budget. Carbon can be obtained from multiple sources, which include (1) CO2 from the atmosphere (2) CO2 con­tained within industrial smoke (3) CO2 from soluble carbonates. For each kilogram of algae that is grown, approximately 1.65 kg of CO2 is used.

The CBSC can be deactivated by leaching of sulfonated species, formation of sul­fonic esters (Kang et al. 2013). Most usually there are five reasons behind catalyst deactivation, these are Sintering, Evaporation, Poisoning, Fouling, and Thermal
degradation often occurred by mechanical damage, high temperature, and corrosion by the reaction mixture. Hence study of leaching catalyst is important for the carbon-based catalysts. Since the functional groups of the carbon based sulfonated acid catalysts consisted of SO3H, COOH, OH, shows the leaching of SO3H and possibly COOH and OH into the reaction medium (Adrian 2012).

J. curcas apart from its use as a biofuel can be put to different uses (Fig. 17.3) (Shanker and Dhyani 2006; Kumar and Sharma 2008). The extract from oil has been used as an insecticide in the control of pests of potato, pulses, and cotton such as cot­ton bollworm (Kaushik and Kumar 2004). The glycerin, a by-product of the trans­esterification process, can be used to make high-quality soap. Press-cake derived from J. curcas can be used as animal and human feed after isolating toxic phorbol esters. The physic nut seed once boiled and roasted is eaten as food in Mexico (Delgado and Parado 1989). Press seed cake can be used as fertilizer owing to its high organic content. Jatropha since ages have found its use in medicine (Dalziel 1955). Seeds are used to treat jaundice, gout, eczema, arthirits, and dermatomucosal diseases. Plant extracts are used to treat cuts, burns, allergies, scabies, leprosy, leco — derma, and small pox. Curcacycline A and some alkaloids such as jatrophine, cur — cain, and jatropham obtained from Jatropha are believed to have antitumor properties (Van den Berg et al. 1995; Thomas et al. 2008) and are used in treatment of HIV and tumor. The roots are reported as an antidote for snake-bites. J. curcas is also used as hedging plant in agricultural fields for protection against damage by livestock.

Lignocellulosic biomass from agricultural and forest residues could prove to be an ideally inexpensive and abundantly available source of sugar fermentation into transportation fuel compared to bioethanol G1 from starch crops. Many techniques are used in the industrial ethanol production process. However, the biggest concern of the process is its effectiveness, low environmental impact, and cost-efficiency. Extensive research has been done on the development of advanced pretreatment, saccharification, fermentation, and purification technologies to prepare more digestible biomass and easy bioconversion of biomass into cellulosic ethanol. New technolo­gies such as catalytic processes are promising due to its high selectivity toward a
desired product although the balance between the overall cost and effectiveness is still being considered for industrial use. The utilization of fuel ethanol for transpor­tation has potential to substitute gasoline and contribute to a cleaner environment. Therefore, the fuel industry will benefit from the efficient utilization of lignocellu — losic biomass for bioethanol G2 production.

Bamboo fibers owe their hardness to the presence of cobble like polygonal cellulose nano grains with a diameter of 21-198 nm in their cell walls. These nano grains are basic building blocks of bamboo fibers. It is observed that nano grain structured fibers are not brittle (Zou et al. 2009). A continuous increase in hardness from center to outer surface is observed (Chand et al. 2006). Hardness of bamboo fibers is same in longitudinal as well as transverse directions. Measured hardness for parenchyma cell wall is 0.23 GPa. Hardness shows a decrease when moving from outer layer to inner layer (Yu et al. 2007). Research has also exposed that young bamboo culms are harder as compared to old culms and have high fracture toughness. The hardness of bamboo culms can be judged by crack deflection and crack bridging (Low et al.

2006) . The hardness of bamboo reduces due to steaming treatment (Lin et al. 2006). Tangled micro-fibrillated cellulose fibers when added to poly lactic acid/bamboo fiber composites, increase the hardness and prevent crack development (Naoya et al. 2004). Bamboo is 23 % harder than oak and 13 % harder than rock maple. Fracture toughness of bamboo is measured to be 56.8 MPa m1/2 (Amada and Untao 2001).

2.4.3 Impact Strength

Impact strength of bamboo fiber concretes is distinctly higher (Ramaswamy et al. 1983). The impact strength of steam exploded bamboo fiber filaments is very high (Tokoro et al. 2008). Bamboo fiber reinforced epoxy resins have impact strength of 63.54 KJ m-2 (Jain et al. 1992). The impact strength of poly lactic acid/bamboo fiber composites increases after addition of micro-fibrillated cellulose (MFC) (Naoya et al. 2004). The high percentage of alkali content in bamboo fibers reduces their impact strength (Kushwaha and Kumar 2009).

The important physical characteristic of the fibers is their fineness. For the determi­nation of the fiber fineness instrumental methods have been developed. Generally there are two methods for measurements of fineness: direct method for the measure­ment of the fiber cross-section, and second is an indirect method for the meas­urement of the length per unit weight. It has been observed that the direct method is not the practical one. The reason for this is nonuniformity of the cross-section of natural fibers which ultimately create difficulty in the computation and measure­ment of the area and diameter of the fibers. So by considering this factor several methods were formed for the determination of the fineness of most commonly used fibers like cotton and wool. The first method is the British Standard Method. According to this method, fibers are chopped to suggested length and weighed. The second method is Arealometer method (ASTM D1448-97) which uses a two chan­nel Wheatstone bridge in a tube. In this method a certain amount of cotton is drib­bled in one of the channels keeping the next one empty. When it is observed that the pressure drop is standardized in both sides, then the given series of equation deter­mines the fineness of the fibers. The SDL Fineness and Maturity Tester (Montalvo 2000) can also be used for the measurement of the fall in pressure across 4 g of

cotton at high and low air flow. On other hand in the Vibroscope method (ISO 2061-95),a tension is applied to the fiber up to the completion of the fundamental frequency. As noticed earlier, these are the traditional methods and are time­consuming and also require specific training. Generally bagasse comes under the category of coarse fiber and has limited access to the testing instruments. (Elsunni and Collier 1996)

7.3.1 Production and Morphological Characterization of A. comosus Leaves

First, differences were found in the amount of leaves of the plants from the first and the second crops. The first crop plants presented an average of 69 leaves, whereas the second crop plants had 105 leaves. Regarding the length of the leaves, a varia­tion of 30-130 cm was found in the first crop plants and of 30-140 cm in the second crop plants (Fig. 7.1). Distribution by leaf length showed that (1) for longitudinal classes between 50 and 100 cm, the first crop plants’ production is statistically higher than the production of the second crop plants; (2) however, the percentage of leaves in classes between 30-40 and 100-140 cm in plants of the first crop is statis­tically lower than the percentage shown by the second crop plant leaves for the same classes, and (3) classes from 20 to 30 cm and 40 to 50 cm and the 140 cm superior class did not show statistical differences in the frequencies or percentages of leaves between the plants from the first crop and from the second crop (Fig. 7.1). The dif­ferences found between the plants from both crops are similar to those mentioned by Perez et al (2011) and Aragon et al (2012)with regard to P3R5 and MD-2 varieties.

The justification these authors give is that the first crop plants are young and their leaves are not completely developed. Therefore, leaves with lengths less than 100 cm from the first crop are fewer than the leaves of the same length of the second crop. Meanwhile, the second crop plants are mature and their leaves are more devel­oped (Perez et al 2011; Aragon et al 2012), therefore concentrating in classes above 100 cm long.

Weight evaluation of the different parts of the A. comosus plant (Table 7.2) showed that the values varied for the first and second crop plants. Total plant weight, base weight, and leaf weight of the second crop plants were significantly higher than the weight of plant parts of the first crop (Table 7.2). However, a great similarity between both crops was found in the evaluation of the distribution of the weight

Fig. 7.2 Proposed scrapping machine model for A. comosus leaves from the first and the second crops from two different plantations. (a) General dimensions (b) structural parts (c) Drum dimen­sions and part and (d) Motor and broadcast of force percentages of the different parts of the pineapple plants; the weight of the bases of the plants did not exceed 28 % of the total plant weight (Table 7.2), while the leaves presented the highest weight (over 70 % of the total weight), which makes evident leaf dominance in A. comosus morphology. These percentages coincide with those reported by Perez et al. (2011) for the P3R5 variety and D’Eeckenbrugge et al.

(2011) and Aragon et al (2012) for the MD-2 variety. They determined that the weight of the base of the plant (stalk) is not above 30 % of the total plant weight. As for most Bromeliaceaes, A. comosus’s growth depends on the development of the small stalk and abundant rose-shaped leaves to satisfy photosynthesis require­ments, necessary for fruit production (Bartholomew et al 2003).