PARTICLE BOARDS FROM COTTON STALK. Introduction

PARTICLE BOARDS FROM COTTON STALK A.J. Shaikh, R. M. Gurjar, P. G. Patil, K. M. Paralikar, P. V. Varadarajan & R. H. Balasubramanya Central Institute for Research on Cotton Technology, Mumbai, India Introduction Environmental concerns have, in recent years stimulated researches in the exploitation of renewable resources. Such researches make better economic sense when they relate to utilization of waste materials like cotton stalk. With its vast area under cotton cultivation, India is undoubtedly the largest producer of cotton stalk among world countries and stands to benefit immensely from commercial exploitation of this putative agrowaste. Profiled in this paper is CIRCOT s saga of R & D efforts that have revealed the economic potential of cotton plant biomass abundant in many Afro-Asian countries. King cotton rules the world of textiles despite inroads made by synthetic fibres. The economy of about 90 cotton growing counties is greatly influenced by cotton. Cultivated in over 30 million ha, the annual world cotton production is about 22 million tonnes constituting 36% of the total fibre production and consumption. In recent years, India has emerged as the second largest producer of cotton next to China. The cotton production in 2009-10 in India stands at 5.1 million tonnes as against China s 6.8 million tonnes. Other major producers are USA, Pakistan, Brazil, Uzbekistan, Turkey, Australia, Turkmenistan, Greece, Syria and Egypt. In area under cotton cultivation, India tops the world list (10.1 Mha) with China (5.4 Mha) and USA (3.1 Mha) closely following. In productivity, however, India lags behind most other countries though in recent years, there has been substantial improvement. Distribution of Cotton in India Two leading cotton growing States in India are Gujarat and Maharashtra which respectively account for 22% and 32% of total area under cotton in the country (Table 1). The average yield is much higher in Gujarat than in Maharashtra on account of better irrigation in the former. These two States together contribute over 50% of India s cotton crop. Table 1 : Cotton Crop in Different States in India (2009-10) State Area (Mha) Production (thousand Productivity (kg/ha) tonnes) Punjab 0.536 272 507 Haryana 0.520 221 425 Rajasthan 0.444 170 382 Gujarat 2.624 1615 615 Maharashtra 3.503 1139 325 Madhya Pradesh 0.646 306 474 Andhra Pradesh 1.319 816 619 Karnataka 0.395 153 383 Tamil Nadu 0.087 85 977 Others 0.078 34 436 Loose Lint - 204 - Total 10.152 5015 494 1

Cropping Season In the northern States of Punjab, Haryana and Rajasthan which are largely irrigated, cotton is harvested in the two months of October & November. Farmers in these areas cut away cotton plants even if some green bolls are still left, so as to clear the land early for the ensuing wheat crop. Stalks are removed in about a month s time. In other regions, which are mostly rainfed, harvesting of cotton takes place from October to February. Cotton stalks are uprooted from around February March and the process goes on till May-June since there is no pressure to vacate the field for any other crop. Low Income from Cotton Farming Relatively low yield in rainfed areas has rendered cotton farming somewhat unremunerative in India. Most farmers are unable to make a living out of cotton cultivation. Ways and means to increase the returns from cotton farming, therefore, need to be explored. Research on By-product Utilisation The diverse products available from cotton crop after the harvest of seed-cotton and ginning include seed, linters, hulls, oil and meal which are classified under the broad head by-produce. Cotton stalk is the other biomass available in the field after the harvest of seed-cotton. In general, there is lack of focus on judicious utilisation of cotton by-produce not only in India but also in all the Afro-Asian countries whose economies are influenced by cotton. The bulk of cotton seed is subjected to what is known as whole seed crushing for extraction of oil and cotton stalks are disposed of by burning in the field itself as otherwise they would harbour several insects and pests which would be harmful for the future crop. A small fraction of seeds is consumed as cattle feed while some of the stalks is used as domestic fuel. In whole seed crushing valuable components like linters, hulls, protein and large fractions of oil go unutilised instead of fetching the much-needed additional returns to farmers. Equally unacceptable is the burning off of cotton stalks that have in recent years proved to be of immense economic potential. Cotton Stalk It is estimated that about 25 million tonnes of cotton stalk is generated in India every year. Most of the stalk produced is treated as waste though a part of it is used as fuel by rural masses. The bulk of the stalk is burnt off in the field after the harvest of the cotton crop as pointed out earlier. Cotton stalk contains about 69% holocellulose, 27% lignin and 7% ash. In contrast to other agricultural crop residues, cotton stalk is comparable to the most common species of hardwood in respect of fibrous structure 3 and hence it can be used for the manufacture of particle boards, preparation of pulp and paper, hard boards, corrugated boards & boxes, microcrystalline cellulose, cellulose derivatives and as substrate for growing edible mushrooms. Technology for Particle Boards from Cotton Stalk Research work on the preparation of particle boards in CIRCOT dates back to 1979-80 when cotton stalk chips were used for the first time (Pandey and Mehta, 1979). Detailed studies have since been made to arrive at the appropriate process sequence and to identify process parameters that would ensure the required qualities for the particle board (Pandey and Mehta, 1980; Gurjar, 1994). The process involves the following steps : Chipping of stalks to 1.5-2.0 cm size; Rechipping to particles of 20 mesh size and 8 mesh size; Mixing of chips with synthetic binder such as urea formaldehyde or phenol formaldehyde; 2

Preparation of a three-layered mat comprising coarser particles for the core layer and finer ones for the top and bottom layers; Pressing the mat between heated platens of a hydraulic press for specific time and pressure. The board thus made is cooled to attain dimensional stability and then cut to the desired size. By using different chemicals and additives, the boards can be made water proof, fire proof, termite resistant, etc. These boards have been found to meet BIS specifications in respect of quality characteristics. Due to the lower cost of raw material and reduced power required for its conversion into finished product, the cost of particle board made from cotton stalk will be much lower than that of boards made from wood. The data presented in Table 2 clearly show that the particle boards from cotton stalks possess all the desirable properties to be used for internal as well as external applications such as false ceiling, partitioning, paneling, etc. Table 2 : Properties of Three-Layered Particle Boards from Cotton Stalk Sr. No. Properties Unit Flat Pressed Three-layer/Multilayer Particle Board IS 3087-1985 Type I Type II Cotton Stalk Particle Board 1 Density Kg/m 3 500 900 ---- 750 2 Average Moisture % 5-15 --- 11 3 Water Absorption % i) 2 h soaking ii) 24 h soaking 10 20 40 80 20 40 4 Swelling Thickness % 8 12 9 5 Swelling due to surface % 6 9 6 Absorption 6 Modulus of Rupture (MOR) N/mm 2 i) Up to 20 mm 15.0 11.0 17.6 ii) Above 20 mm 12.5 11.0 7 Internal bond strength N/mm 2 i) Up to 20 mm 0.45 0.3 0.51 ii) Above 20 mm 0.40 0.3 8 Screw withdrawal strength Face Edge N 1250 850 1250 700 1400 860 9 Nail withdrawal strength N 1250 --- 1300 Process Parameters and Product Quality Increase in resin content results in improvement of product performance. Density of boards and modulus of rupture are found to increase while water absorption and surface swelling show progressive decline as the resin content is increased. Data in Table 3 demonstrate that by altering the process variables, it is possible to get particle boards of any desired quality. Table 3 : Properties of Particle Boards from Cotton Stalks with Urea Formaldehyde as Binder Resin Content (%) Thickness (mm) Density (kg/m 3 ) Modulus of Rupture Water Absorption 3 Swelling due to Surface Absorption (%) (N/mm 2 ) (%) 0 7.1 700 6.1 77 28 3 7.4 720 7.4 57 22 5 7.6 760 9.3 42 18 8 8.0 780 12.4 33 12 10 8.2 820 13.3 31 10 12 8.4 840 13.9 28 9 13.5 8.5 840 17.4 25 8

15 8.9 880 18.6 22 6 Uses of Particle Boards The applications of particle boards are many. The application areas identified include door panel inserts, partitions, wall panels, pelmets, furniture items, floor and ceiling tiles, etc. for residential houses, commercial buildings, schools, hotels, theatres, etc. In recent years, particle board is being used increasingly in place of commercial plywood in the preparation of printer blocks. In all the above applications, substitute materials for particle boards are timber, commercial plywood, marine plywood and block board in general and for false ceilings in place of plaster of Paris. The advantages of particle board are many : It is free from natural defects of wood, like tendency for warping. It is easier to fix. For instance, the factory-made panel doors from particle board are available in a ready-to-fix form. Similarly, for wall panelling, false ceilings, table tops, etc., pre-laminated or preveneered particle boards can be used with advantage. It is cheaper than substitute materials. With proper protective surface coating and edge covering, particle board can be made termite proof and fire resistant. It can take a variety of surface finishes, like laminations, veneers, paint, varnish, polish, etc. Attractive wall paper can also be used as surface finish for particle boards. Even though the process for the preparation of particle boards from cotton stalks was developed a decade ago, it was not accepted by the boards industry for commercial adoption. Some of the important reasons being Absence of cost effective supply chain mechanism Absence of pilot plant facility for fine tuning of technology and demonstration Non availability of data on techno-economic feasibility of the process. To address some of the above issues CIRCOT had submitted a project proposal to the Common Fund for Commodities (CFC), Netherlands, through the International Cotton Advisory Committee, USA for seeking financial assistance. The CFC realized the importance and potential of the project and sanctioned an amount of US$ 918,886 for undertaking the above study. Some of the important achievements made in the project are described below: Estimation of Availability of Cotton Stalk In Maharashtra, where cotton crop is grown mostly under rainfed conditions, stalks yield was as low as 1 to 1.5 tonnes per ha. The stalks yield from Karnataka ranged from 1 to 2.5 tonnes/ha in case of rainfed crop and up to 4 tonnes/ha from irrigated fields. The data clearly showed that the yield of cotton stalks from Maharashtra is the lowest. It was also noted that cotton type (variety/hybrid) plays a very important role besides conditions of growth. The information on State-wise availability of cotton stalks is given in Table 4. The survey revealed that in the North, the major part of cotton stalks is used as domestic fuel. However, farmers were ready to part with at least 50% the cotton stalk available with them for a payment of Rs. 400 to 500 (US $ 8 to 10 ) per tonne. In Gujarat the stalks are mostly burnt in the field itself. In Maharashtra, though farmers are using the stalks as household fuel, they were willing to sell it for as low as Rs. 300 to as high as Rs. 500 per tonne. In Karnataka, the survey showed that most of the farmers use cotton stalk as fuel. Some of them exchange the stalks for farm yard manure. They expressed their willingness to sell the stalks for a price of Rs. 500 per tone (1 US$ = Rs. 45/-) 4

Table 4 : Availability of Cotton Plant Stalks in India (2008-09) State Area (million ha) Availability of Stalks (million tonnes) 1. Gujarat 2. Maharashtra 3. Andhra Pradesh 4. Punjab 5. Haryana 6. Madhya Pradesh 7. Karnataka 8. Rajasthan 9. Tamil Nadu 10. Orissa 11. Others 2.39 3.12 0.96 0.59 0.53 0.63 0.37 0.35 0.13 0.06 0.04 7.17 6.24 2.40 2.95 1.76 1.60 1.26 0.74 0.70 0.27 0.12 0.07 Total 9.17 25.28 Collection and Cleaning of Cotton Stalk Cotton is a seasonal crop harvested in India from October to February. Cotton stalks which are available only between December and May will require storage over several months to ensure adequate raw material supplies to board manufacturers for the entire year's production. Cotton stalks are bushy in nature and have very low bulk density. Collection and transportation are, therefore, expensive. Further, on storage in stick form, cotton stalks get degraded by insect attack. Success of cotton stalks as an industrial raw material would depend on the establishment of a sustainable supply chain to reach them to the industry. The entire cost economics of board manufacturing technology and the acceptance of cotton stalk by industry will depend to a large extent on the cost of raw material in a readily usable form made available at the factory gate. Therefore, the logistics of economic collection of cotton stalks, chipping and transportation from field to industry, and its proper storage in different forms at various centres are crucial factors that decide the economic viability of this raw material. Trials were conducted in three successive seasons to arrive at the most economic mode of cotton stalk collection in and around Nagpur where the crop is raised under rainfed conditions. In this region after the picking of seed cotton, the stalks are not cleared from the field immediately since there is no subsequent crop. The study started right from the stage of sensitizing farmers about the utility of cotton plant stalks. It is comparatively easier to uproot the stalks immediately after the picking is over since the moisture still present in the soil facilitates uprooting. A metallic device available locally helped in uprooting the stalks effortlessly as compared to manual pulling. It has been observed that as many as 7-8 labourers could clear the stalk from one hectare of land in a day of 8 hours. Although there was no significant difference between manual pulling and uprooting with the help of the mechanical device in respect of speed, the drudgery involved in bending and pulling with hands could be avoided in the latter case. In view of this, the simple mechanical device is recommended for uprooting the stalks. The stalks thus collected should be left for 4 to 5 days in the sun during which time, the leaves are shed. The boll rinds can be removed by gently beating the stalks on a wooden mallet. The cleaned stalks could then be subjected to chipping at a nearby chipping centre. 5

Three different models were attempted initially for economic collection and transportation of cotton stalks at three different locations near Nagpur: Among the various models attempted, the most suitable model is the third model which comprises uprooting of stalk, storage, manual cleaning, chipping by use of a tractor-driven chipper at a centralized chipping centre not farther than 5 km from the field and transportation of chips to the factory within 50 km distance by a truck. Transporting cotton stalks beyond 5 km before chipping and beyond 50 km after chipping so as to make it available in an appropriate form to the industry would not be an economically feasible endeavour. On an average, the cost of cleaned and chipped stalks to be made available at the factory gate situated within 50 km from the production centre (farm) would workout to about Rs.1500-2000 (US $ 30.0 40.0) per tonne of the raw material with 10% of moisture. Cost of Ready-to-use Cotton Stalk Chips Using the large volume of data on collection, chipping and transportation of cotton stalks, it has been possible to work out the economics of each of these operations. From this analysis the cost of cotton stalk chips made available at the particle board factory has been arrived at. Details are given in Tables 5 and 6. The raw material cost for particle board manufacture from cotton stalk thus works out to Rs. 1960 (US $ 39.2) per tonne of the ready-to-use material. Table 5: Cost of Collection and Chipping of Cotton Stalks Cost per tonne Operations Rupees US$ Uprooting and cleaning 500 10.0 Chipping 230 4.6 Tractor hiring 360 7.2 Total 1090 21.8 Table 6 : Total Cost of Ready-to-use Cotton Stalk Chips Delivered at Factory Site Operation Rupees Cost per tonne US$ Labour charges for uprooting, cleaning and chipping 1090 21.8 Transportation charges 320 6.4 Loading and unloading charges 50 1.0 Raw material cost 500 10.0 Total 1960 39.2 Transportation of Stalks and Chips A critical study of the logistics of cotton stalk collection, chipping and transportation has revealed the following facts : Transporting chipped cotton stalk is more economical than transporting the stalk as such. 6

It would be appropriate to employ bullock carts and tractor trolleys to carry cotton stalk to the chipping centre and use lorries to deliver the chips at the factory. Transporting distance plays a major role in deciding the effective cost of the raw material. Fifty kilometers should be considered as the maximum permissible distance for economic transportation of chipped material. Storage Trials In order to find out the shelf life of cotton stalks, a large quantity of the unchipped material was stored in the open, on a stone platform. Similarly, two lots of chipped cotton stalks packed in gunny bags were also stacked, one lot in the open and the other inside a godown. Observations were made every month for colour and insect attack, and chemical analysis was done once in a month to find out the changes if any in chemical composition (Table 7). The following facts emerged from this trial : Insect attack is rampant in unchipped stalks kept in shade or in the open. No significant change in the chemical composition occurs in the case of chips stored in godown. Chipped stalks are not susceptible to insect attack. A marginal reduction in holocellulose content is noticeable in chips stored in the open. Table 7 : Data from Chemical Analysis of Stored Cotton Stalk Chips Sl. No Month Moisture (%) Lignin (%) Holo Cellulose (%) Ether Extractives (%) A B A B A B A B 1 July 14.2 16.0 26.6 25.4 82.1 77.1 7.1 7.2 2 August 14.0 15.9 26.1 25.0 81.4 76.4 7.0 7.1 3 September 12.0 11.9 26.0 24.8 81.2 75.7 7.0 7.2 4 October 11.2 12.9 25.9 24.5 81.1 75.4 6.5 6.8 5 November 11.8 11.4 25.8 24.2 80.9 75.2 6.8 7.1 6 December 11.1 11.2 25.5 24.1 80.7 75.2 6.7 6.5 7 January 11.3 11.4 25.2 24.1 80.5 75.1 6.7 6.8 8 February 11.3 11.4 25.5 24.7 81.1 75.0 6.5 6.3 9 March 11.2 11.4 25.5 24.6 80.9 74.7 6.9 4.5 10 April 11.0 11.1 25.6 24.5 80.5 75.1 6.6 6.4 11 May 10.1 11.5 25.3 24.7 80.4 74.9 6.5 6.4 12 June 13.2 14.1 25.2 24.4 81.0 74.8 6.4 6.3 A : Stored in shed; B : Stored in the open Pesticide Residues in Cotton Stalk Cotton is a long duration crop and hence it is necessary to apply a number of pesticides at various stages of its cultivation. Broadly, the pesticides used on cotton can be divided into 3 classes: organochlorine, organophosphorous and synethtic pyrethroids. Pesticides with long photostability alone were considered in the present study. Cotton stalk samples were collected from the fields of Sirsa in Haryana State in northern India. Based on the history of pesticide application prevalent in that area, chemicals such as endosulphan, 7

quinol-phos, monochrotophos, dimethoate, cypermethrine and effective synthetic pyrythroids were selected for analysis. Cotton stalk samples with and without the bark were pulverised and analysed for the presence of the above pesticide residues. After standardization of the procedure for extraction of the pesticides from cotton stalk adopting procedures based on AOAC standards, the estimation was carried out by using a gas chromatograph fitted with ECD and MS detector systems. The minimum detection level of the procedure was 1 PPB. Interestingly the study did not reveal the presence of any of the pesticides on the cotton stalk analysed. Hence, it can be safely claimed that the boards made from cotton stalks are free from contamination by the above pesticides. A Model Cotton Stalk Supply Chain for a 20 TPD Particle Board Plant It is known that for producing 1 tonne of boards, about 1.5 tonnes of chips are required. Therefore for running a 20 TPD particle board plant, 30 tonnes of chips would be required each day. Our studies have shown that it is possible to get about 1.5 tonnes of ready-to-use chips from one hectare land around Nagpur. Hence if a factory is to run only on cotton stalks it is necessary to get the material from 6000 ha of farm land which will provide 9000 tonnes of chips for board production in a 20 TPD plant working for 300 days in a year. Storage CIRCOT study has shown that cotton stalks are normally uprooted in Nagpur area when the plant is almost dry (devoid of leaves). If such plants are uprooted and left in the field for three days and manually cleaned to remove the boll rinds before being subjected to chipping, the chipped material would be left with a moisture of around 12%. During transportation to the factory, the percentage of moisture stabilizes at about 10%. Considering that the chips have to be stored in the factory premises for at least one month, about 900 tonnes are to be stacked in its premises and the rest to be stored in 9 decentralised places by groups of farmers (say in 9 villages connected well with transport services). Chipping Stations It has been estimated that about ten chipping stations are required to be set up. Each chipping station must be provided with one tractor-driven mobile chipper (outsourcing). Each chipper has an output rate of about 500 kg/h and can provide about 3-4 tonnes per day and in a month it is possible to generate about 90-120 tonnes of chips. Each chipping station will have to store about 1000 tonnes of chips. These chips will be stored in three stockpiles of 3 metres height and each pile is to be covered by polythene sheets to prevent spoilage during rainy season. The stock piles will be adequately separated from one other so as to facilitate loading of chips in trucks. The bulk density of cotton stalk chips is about 0.14 g/cc. The average area occupied by a 3-metre high stockpile would be around 70 m 2. The space required in each chipping centre would, therefore, be around ¼ of an acre. Cotton Stalk Collection for Each Chipping Station As said earlier, about 1000 tonnes of chips are to be generated and stored in each chipping centre. For this, stalks must be collected from 600-700 hectares of land. Based on earlier trials at CIRCOT, four labourers can uproot and collect stalks from one acre in a day. This means, 10 persons are required to uproot the stalk available in 1 hectare. This also means that 10 persons would get employment for one week, only for uprooting. The same number of persons are required for cleaning the material as well. Chipping will employ four persons daily for one month. 8

Supply of Cotton Stalk Chips The chips will have to be transported to the factory under the direct supervision of the factory itself to ensure that supply takes place at the required rate. Establishment of 1 TPD Pilot Plant One-tonne-per-day (1 TPD) pilot plant was commissioned for preparation of particle boards. Accordingly a pilot plant of indigenous design was procured and installed at the Ginning Training Centre of CIRCOT at Nagpur (India). The layout of the pilot plant is shown in Fig. 5 while the process sequence is illustrated in the flow-chart in Fig. 6. The pilot plant comprises an array of several machines : Hammer Mill Drum Chipper Rechipper Rotary Dryer Glue Blender Mat Former Pre Press (cold) Hydraulic Hot Press Cutting Machine Sanding Machine The component machines except the last two are linked by conveyors that transfer the material from one stage to the next till the boards are formed. Fig. 5: Layout of Pilot Plant 9

Pilot Plant at GTC Nagpur Fig. 6 : Flow-chart of Particle Board Pilot Plant 10

Cotton Stalk Hammer Mill Dryer Rotary Screen Over Size particle Coarse Fine Silo Resin, Wax, Hardener etc Silo Glue Glue service Glue service Glue Mat Mat Fine particle layer Coarse particle layer Fine particle layer Carrier plate Cold press Hot Press Sanding M/c Trimmed Board Finished Board Raw Board Cut to size saw Board Making Trials on the Pilot Plant After commissioning of the plant, various trials were undertaken for standardizing the process parameters like concentration of resin, temperature, pressing time, etc., to get good quality particle boards from cotton stalks on the automatic pilot plant which is very similar to commercial plants. The details of various standardization trials undertaken on the pilot plant are given in Table 8 while the properties of particle boards prepared under optimized conditions are gathered in Table 9. The data in Table 9 clearly show that particle boards from cotton stalks meet the BIS specifications in respect of quality. Table 8: Standardization Trials (18 mm Particle Boards) on Pilot Plant Sl. No. Core (%) Face (%) Resin (Solid basis) (%) Wax (Solid basis) (%) 11 Pressing time 1 60-70 30-40 UF resin 1.0-1.2 3 min at high (8-10) Pressure (200 2 60-70 30-40 UF resin 0.8-1.0 kg/cm 2 ) Temperature ( 0 C)

3 60-70 30-40 UF resin (6-6.5) + Malamine (1-1.5) 4 50-60 40-50 UF resin (7-8) UF : Urea formaldehyde (7-8) + 0.8-1.0 1.0-1.2 8 min at low Pressure (100 kg/cm 2 ) 130-140 Table 9: Properties of Particle Board Made on Pilot Plant Using Optimised Conditions Parameters Urea Formaldehyde Bonded BIS Specification Cotton Stalk Boards Thickness (mm) 18 - Density (kg/m 3 ) 671 500-900 Modulus of Rupture 14.6 11.0 (N/mm 2 ) Internal Bond Strength 0.6 0.3 (N/mm 2 ) Screw /Nail Withdrawal 2118 1250 (Face Newton) Water Absorption (%) 2 h 28 40 24 h 31 80 Surface Absorption (%) 3 9 Material Balance After optimizing the process parameters on the pilot plant, regular production trials were undertaken and boards of various thicknesses, densities, etc. were made. On the basis of these production trials and the systematic data thus collected, a material balance for preparation of particle board from cotton stalks was worked out, as shown in the following chart. Material Balance for the Preparation of Particle Boards from Cotton Plant Stalks 12

Cotton Stalk chips (10 % moisture) (1 tonne) 5 % Material loss Rechipped Material (950 kg), 10% moisture 7 % loss Dried Material (884 kg), 3 % moisture 8 % material loss Particle Separation Loss (813 kg), 3 % moisture Resin + Wax Addition Finish Material (959 kg), 12 % moisture Mat Formation (911 kg) 5 % material loss 6 % loss Pressing of Board (856 kg), 6 % moisture Trimming & Sanding loss 20 % Finished Boards (685 kg), 6 % moisture The most significant facts that emerge from the chart are the following : One tonne of cleaned cotton stalk chips with 10% moisture yields 0.7 tonne of plain boards with 6% moisture. To prepare 1 tonne of plain boards with 6% moisture, about 1.4 tonnes of cleaned cotton stalk chips with 10% moisture are required. 13

Particle boards produced on pilot plant Commercial Trials CIRCOT s particle board technology subjected to refinement on the pilot plant was tried on an industrial scale in large board manufacturing units. In the first instance, about 30 tonnes of ready-to-use cotton stalk chips were supplied to M/s Ecoboard Industries Ltd. at Velapur near Pandharpur in central India followed by a second lot of 50 tonnes. The chips were delivered from Nagpur, and boards of 13.5 x 6 size were prepared with different thicknesses (9 mm, 12 mm & 18 mm) and surface finishes. Laminated boards thus manufactured were used for making different furniture items and also for panelling some rooms in CIRCOT, Mumbai, GTC of CIRCOT, Nagpur, DOCD, Mumbai and ICAR Headquarters, New Delhi. Tests results shown in Table 10 indicate that it is possible to prepare good quality boards in the existing industry without any modification. Table 10 : Properties of Cotton Stalk Boards Made in Industrial Trials Properties Interior Grade Boards BIS Specification 12 mm 18 mm Density (kg/m 3 ) 713.1 699 500-900 Modulus of Rupure (N/mm 2 ) 15.4 12.0 11.0 Tensile Strength (N/mm 2 ) 0.9 0.5 0.3 Water Absorption (%) 2 hours 20.4 56 40 Water Absorption (%) 24 hours 42.2 95 80 Screw Withdrawal (N)Face 1762 1610 1250 Techno-economic Feasibility of Particle Board Plants The technical feasibility of particle board manufacture from cotton stalk was examined on the basis of industrial trials conducted at M/s Eco-board Industries Pvt. Ltd., Pune and Archid Ply Industries, Mysore. In both the industries, the trials were successful and good quality boards suitable for lamination were manufactured. No technical problems were encountered during the processing and no changes or modifications in the existing plant were found necessary. For an examination of the economic viability of cotton stalk as raw material for particle board manufacture, a 30-tonne trial was undertaken at M/s Eco-board Industries Pvt. Ltd., Pune having installed capacity of 200 tonnes/day but running at 60% capacity utilization. In these trial boards of 9 mm, 12 mm and 18 mm were prepared. The data in Table would substantiate the fact that particle board production from cotton stalks in an established board manufacturing unit is indeed an economically viable proposition. 14

Thickness Density (g/cc) Production cost per sq. ft. Selling Price per sq. ft. Profitability % Rs. US $ Rs. US $ 9 mm 0.73 13.94 0.28 17.1 0.34 22. 7 12 mm 0.72 15.00 0.30 18.63 0.37 24.2 18 mm 0.72 19.25 0.38 24.53 0.49 27.4 Cost Estimation for a Particle Board Plant of 10 TPD Capacity On the basis of extensive information gathered from wide ranging R & D efforts under the project, it has been possible to work out the profitability of particle board plants. For a 10 TPD plant the capital investment comprising land, buildings and plant & machinery will work out to over Rs. 58 million (US $ 1.16 million) while the production cost after duly considering depreciation, interest on investment etc would be around Rs. 38.76 million (US $ 0.78 million). The cost of production per tonne of particle board would be about Rs. 12,920 (US $ 258). At current selling price levels for particle boards, the return on investment will work out to about 19%. Details are given below in tabular form. Production Highlights : Production capacity : 10 TPD (384 boards of 8 x4 x12 mm), Raw material used :15 TPD of cleaned chips/day No. of days of production in a year : 300 No. of shifts per day : 3 Total production in a year : 3000 tonnes Project Cost and Production cost in case of a 10 TPD Plant A Capital Investment Rs. (Million) US $ 1. Land & Building Land : about 1 hectare 2.50 50000 Building : (Area : About 10,000 sq.ft., raw material 4.50 90000 storage) 2. Plant and Equipment 42.20 844000 3. Auxiliary and service Equipments, Margin money for 90.00 180000 working capital Total Project Cost 58.20 1164000 B Cost of Production 1. Raw Material & Utility 20.50 410000 2. Labour & Supervision 3.51 70200 3. Repairs, Maintenance & Overheads 2.80 56000 (I) Total Manufacturing Cost 26.81 536200 (II) General Expenses 1.75 35000 (III) Depreciation & Interest 10.20 204000 Total cost of production B (I+II+III) 38.76 775200 Cost of production per tonne of board Rs.12,920 258 15

Profitability of a 10 TPD Particle Board Plant Rs. (Million) US $ 1. Gross Annual Income 49.77 995400 2. Annual Cost of Production 38.76 775200 3. Annual Return (2-3) 11.01 220200 4. Return on Investment (ROI) 19% 19% * Selling price per unit (8 x4 x12 mm) @ Rs. 13.5 per sq. ft. = Rs. 432.00 (US $ 8.64) Cost Estimation for a Particle Board Plant of 20 TPD Capacity A similar exercise has been done in respect of a 20 TPD plant for which the capital investment including cost of land, buildings and plant & machinery works out to over Rs. 75 million (US $ 1.50 million). The production cost, after taking into consideration depreciation, interest on investment etc., works out to about Rs. 74.60 million (US $ 1.49 million). The production cost per tone of particle board would be about Rs. 12430 (US $ 249). The return on investment would be about 33.5% which is significantly higher than for a 10 TPD plant. Details are shown in tabular form. Production Highlights : Production capacity : 20 TPD (770 boards of 8 x4 x12 mm) Raw material used :29 TPD of cleaned chips/day No of days of production in a year : 300 No. of shifts per day : 3 Total production in a year : 6000 tonnes Project Cost and Production cost in case of a 20 TPD Plant A Capital Investment Rs. (Million) US $ 1. Land & Building Land : about 1 hectare 2.50 50000 Building : 25,000 sq.ft. 9.05 181000 2. Plant and Equipment 50.00 1000000 3. Auxiliary and service Equipment 2.50 50000 4. Margin money for working capital, preoperative 11.17 223400 expenses, contingency etc. Total Project Cost 75.22 1504400 B Cost of Production (80% capacity utilization) 1. Raw Material & Utility 41.50 830000 2. Labour & Supervision 5.50 110000 3. Repairs & Maintenance 2.70 54000 4. Plant overheads 1.00 20000 (I) Total Manufacturing Cost 50.70 1014000 (II) General Expenses 3.10 62000 (III) Depreciation & Interest 20.80 416000 Total cost of production B (I+II+III) 74.60 1492000 Cost of production per tonne board Rs. 12430 249 Profitability of a 20 TPD Particle Board Plant Rs. (Million) Us $ 1. Gross Annual Income 99.79 1995800 2. Annual Cost of Production 74.60 1492000 3. Annual Return (2-3) 25.19 503800 4. Return on Investment (ROI) 33.5% 33.5% * Selling price per unit (8 x4 x12 mm) @ Rs. 13.5 per sq. ft. : Rs. 432.00 (US $ 8.64) 16

Conclusions from the Techno-economic Study A particle board plant with an installed capacity of 10 tonnes per day and involving a capital investment of about Rs. 60 million (US $1.6 million) can ensure a profitability of about 20% with cotton stalk used as the raw material. A plant with a higher capacity of 20 TPD can bring higher returns of up to 33%. For sustainable supply of raw material, an agency should be identified for organizing collection and chipping of cotton stalks and delivering the chips at the particle board factory. Existing particle board plants manufacturing boards from hardwood, bagasse, etc. can use cotton stalk as an additional raw material. Post Project Scenario The successful completion of the project in 2009 encouraged many farmers, entrepreneurs and board industries particularly in Maharashtra and Gujarat to collect stalks for use in board making. a) M/s. Godavari Particle Board Palnt (10 TPD) near Nanded in Maharashtra have been using cotton stalks for the preparation of particle boards. They are preparing blended boards also (cotton stalks and bagasse). They are able to collect about 500-1000 tonnes of cotton stalks through an organized collection mechanism. This exercise provided employment specifically to landless labourers. About 100 farmers are involved daily in collection, chipping and transportation. b) A 100 TPD particle board plant based on cotton stalks was commissioned in 2009 by M/s. Rushil Decor Ltd. In Dhrangadhra village in Surendranagar District, Gujarat. Their annual requirement of cotton stalks is 50,000 tonnes. They have identified six cotton stalk collection centres, each centre covering an area of 8000 ha to 25,000 ha in a distance of about 15-20 km. They identified contractors, panchayat representatives, self help women groups and Rural Development Agencies to undertake this job. This plant with innovation collection mechanism generated 4,00,000 man days employment annually benefitting 1000 farmers and 5,000 landless labourers. c) Based on CIRCOT technology, CIRCOT in collaboration with MITCON consultancy services prepared a bankable project proposal for setting up of a 10 TPD particle board manufacturing plant from 100% cotton stalk at Washim, Maharashtra. Ministry of Social Welfare, Govt of Maharashtra sanctioned a loan of 680 lakhs to Tulsai Magasvargiy Audyogik Sahakari Sanstha (TMASS), Washim. The construction of the plant is in progress and expected to be over by June, 2011. About 100 farmers will be involved in the procurement and supply of cotton stalks and about 150 persons will be involved in direct and indirect employment. Apart from this, M/s. Aurobindo Laminations in Nagpur are using cotton stalks in making particle boards. Acknowledgement The authors wish to acknowledge the following: 1. CFC, Netherlands for the financial assistance. 2. ICAC, USA for constant help, guidance, supervision and encouragement. 3. ICAR, for providing all the infrastructural facilities for effective monitoring, guidance and permission to participate in the meeting and presentation of data. 4. To all my project colleagues, specially to Dr. S. Sreenivasan, Former, Director, CIRCOT for constant and continuous support and guidance. 5. To. M/s. Eco-Boards, M/s. Jolly Boards, M/s. Archid Ply and other industries for permitting to undertake commercial trials. 17

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