FORM -2
THE PATENTS A C T, 1970 (39 OF 1970)
COMPLETE SPECIFICATION
(SEC-10, RULE 13)
"METHOD FOR CHLORIDE REMOVAL FROM BIOMASS."
ABELLON CLEANENERGY LIMITED,
A Company Incorporated under The Companies Act, 1956
having its registered address at
3rd Floor, Sangeeta Complex,
Nr. Parimal Crossing, Ellisbridge,
Ahmedabad-380 006, Gujarat State, India,

Field of Invention
This present invention relates to removal of chloride from bio-mass for its further use as input for solid biofucl. Such biomass could be forest waste such as grasses, other forest by-producls such as bark, saw dust, agriculture residue such as sweet sorghum bagasse, 5sugarcane bagasse, coconut shells, groundnut shell, cotton stalk, straw etc. In particular the present invention describes a method of treating biomass input to remove chloride so as to converl it into a combustible fuel product in boiler and other industrial applications.
Background of the invention
10
Since fossil fuel has become a finite energy source, in the last decades many efforts have been put into the production of alternative energy materials. These alternative materials should not only be affordable and readily available, they also should be preferably derived from renewable sources. Among the existing renewable alternatives to fossil
15fuels, biomass has raised great interest. Wood or wood by-products, saw dust, farm field left over, cotton waste, grass cuttings, groundnut shell are prime examples of renewable energy materials while production of fuel briquettes or pellets. The main source of firewood has been found in native forests. It is simple to imagine that these sources are limited sources, and that an increase of wood fuel consumption would not only lead to an
20increase in the price of these raw materials but also to the loss of many forests since a tree needs a long growth period, which decreases the desirability of wood as a renewable energy source.
Enormous quantities of wood waste material are produced both by recycling and as 25byproducts of industrial and commercial activity. For example, there are number of lumber mills in the India, which continuously generate sawdust and wasted wood. As an alternative to wood-based products, other cotton waste, agriculture materials, such as sugar cane, groundnut shell, grass and field waste have been investigated.
30Biomass is a potentially carbon dioxide neutral and renewable energy resources. As biomass fuels are rich in ash compared to oil and natural gas, ash related problems have a strong impact on the lifetime, availability and operation of biomass combustion
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gasification systems and thus have great economic and ecological relevance. Chlorine and alkali metals compounds in biomass are problematic especially for some herbaceous and agricultural waste fuels. The combination of alkali metals like potassium and sodium under combustion and gasification conditions leads to the production of gaseous and 5condensing potassium and sodium chloride that are troublesome for boiler operation. The alkali metal compounds being extremely corrosive and deposit forming at combustion and gasification conditions create a great risk of failure, unexpected shut downs and costly repairs.
l0Addition of chemical materials (additives) as a practical and cheap treatment to counter the ash-related problems such as slagging of furnace walls, fouling and increased corrosion of super heater tubes due to the chlorine rich deposit has been tested. Different additives such as kaolin, dolomite have been identified as promising additives but the use of such commercially available additives is often not financially attractive because of
15their higher costs. Thus it is interesting for power generators to to search for alternatives to the commercial and effective products.
U.S. Patent Application No. 20080172933 describes a method of preparing fuel pellets using agriculture fiber feedstock wherein the method include a step of mixing feedstock
20such as agricultural whole grain and seed fiber with a sequestering agent for sequestering alkali metal vapors and raising the fusion point of the inorganic elements during combustion of the pellets. The sequestering agent may be calcium carbonate added in amounts up to about 0.5% by weight. The pellets contain additives comprised of ammonium nitrate, calcium, manganese, magnesium, aluminium, barium, iron, potassium
25and amorphous silicate, which sequester potassium and chlorides and alter the fusion point of the inorganic elements present in the fuel.
U. S. Patent No. 5,375,540 describes a combustion system capable of burning fuel pellets and also discusses the problems associated with trying to burn many natural biomass 30materials, including whole corn. The inventors acknowledge that these fuels present a serious problem of clinker formation from ash. They attempted to solve the problem by modifying the design of the burner.
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Many additives, such as those proposed in accordance with U.S. Patent No. 3,240,573, have an environmentally suspect origin and produce doubtful degradation products, since they constitute rest products from mineral oil and coal-refining processes, such as tar, 5asphalt products and synthetic waxes, for instance. According to U.S. Patent No. 3,240,573 polymer binders, such as formaldehyde-based binders, are also used.
The Johnston U.S. Pat. No. 4,236,897 mentions bagasse among a number of other
natural cellulosic materials, which may be pelleted by combining them with
l0thermoplaslic polymeric material.
. It is an object of the present invention to develop a process for treating biomass to remove water soluble chloride enabling manufacture of high quality pellets produced without the need for bonding agents such as polymeric thermoplastic materials or special
15combustion apparatus to handle ash fusion issues.
Del ail description of invention
The present invention involves a biomass treatment method and use of processed biomass 20materials in order to obtain solid biofuel pellets.
'Solid biofuels' is meant in accordance with the invention combustible, non-fossil substances, essentially substances which derive from the plant kingdom and which are not gaseous or liquid at temperatures beneath +100°C. On the other hand, the term 25biofuels does not include those, which are comprised substantially of fossil fuels or are otherwise derived from the mineral kingdom, such as coal, coke, brown coal and oil shale.
'Bio-waste' is meant in accordance with the invention as forest waste such as grasses, 30other forest by-products such as bark, saw dust, agriculture residue such as sweet sorghum bagasse, sugarcane bagasse, coconut shells, groundnut shell, cotton stalk, straw etc.
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This invention relates to a method of treating biomass to remove chlorides and use for producing solid biofuel, for instance in the form of pellets with a high energy content. Bio-mass in this case are material like for instance forest waste such as grasses, other 5forest by-products such as bark, saw dust, agriculture residue such as sweet sorghum bagasse, sugarcane bagasse, coconut shells, groundnut shell, cotton stalk, straw etc., either as such or in combination of other types of biomass.
Accordingly, the present invention provides a method of preparing fuel pellets from any
l0one or more of above mentioned input treated by washing with water. The water wash can be effected by suitable method such as dipping the material in water or spraying water on the material and subsequent removal of water. Further biomass can be warned on line by spraying water when it is being transported on a conveyor belt. The water used, to remove water soluble chloride portion of the said biomass is removed by suitable
15method such as, separation by gravity, vacuum filtration or by positive pressure of air or other suitable gas. As per another embodiment of the invention such a water wash treatment can be given to biomass after size reduction by shredding or grinding the biomass to powder form. Yet another embodiment of the present invention is treating biomass processed for size reduction and treatment by water in a reactor where biomass
20is packed as a bed and water is sprayed on bed of biomass. At the end of holding period water is removed by pressurizing the vessel from top. Further such treated material is used to manufacture pellets with or without binder in the suitable form such as compounds, composites, aggregates, agglomerates, granules, powder, pellet and briquettes of different size ranging from 1 mm and above and of different shapes, odor
25and color.
Example 1:
Different biomass samples were grind to about 1 centimeter or less and treated with water
to remove water soluble chloride. Biomass sample lOg was soaked in 90ml demineralized
30water for 30 minutes. Washed biomass was separated by filtration under vacuum and
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dried at 80 degree centigrade The chloride content of untreated and washed samples was determined by Mohr method. The analysis results are as described in Table - 1. Table 1

5Example 2;
In another experiment biomass samples were shredded to about 1 to 2.5 inch size and used. Shredded sample of each biomass 100 g was soaked in tap water 900 ml for different time interval in order to optimize duration of wash treatment. Samples were taken at different time intervals, separation and drying and chloride estimation was lOcarried out as described in example 1. The analysis results are as described in Table 2.
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Table 2


We Claim,
1. A method for removal of chloride /potassium from bio mass for producing
high quality pellets of bio-fuel the high energy content produced without using bonding 5agents such as polymeric thermoplastic materials or special combustion apparatus to handle ash fusion issues, the said method comprising the following steps,
a) treating a bio mass by washing with water by dipping the material in water
or spraying water on the material and subsequent removal of water;
b) washing bio mass on line by spraying water when it is being transported on
10a conveyor belt to remove water solublechloride portion of the said bio mass;
c) removing water soluble chlorine by gravity separation followed by vacuum filtration or by positive pressure of air or other suitable gas;
d) drying the treated biomass by solar drying, in an oven and/or by blowing hot air;
15e) the treated biomass obtained at step ( d ) used for manufacturing solid
biofuel pellets with or without using binder.
2. A method as claimed in claim 1, wherein the bio mass size reduced by
shredding or grinding the biomass to powder form can be recycled two to three times, 20
3. A method as claimed in claim 1, wherein the compounds composites
aggregates agglomerates, granules, powder, pellets and briquettes of different size ranging from 1 mm and above and of different shapes odor color,
254. A method as claimed in claim 1, wherein the bio mass grinded to about 1 ,
centimeter or less and treated with water soluble chloride, bio mass sample 10 g was soaked in 90 ml de-mineralized water for 30 minutes, washed bio mass was separated by filtration under vacuum and dried at 80 C centigrade,
30
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5. A method as claimed in claim 1, wherein the bio mass selected from a
forest waste such as grasses other forest by products such as bark, saw dust wasted wood
agriculture residue such as sweet sorghum bagasses, sugarcane bagasse, coconut shells
groundnut shell, cotton stalk, straw, grasses,
5
6. A method for removal of chloride /potassium from bio mass for producing
high quality pellets of bio-fuel the high energy content produced without using bonding
agents such as polymeric thermoplastic materials such as here in described with reference
to foregoing examples.