DESC:FIELD
The present disclosure relates to fertilizers.
DEFINITIONS
As used in the present disclosure, the following terms are generally intended to have the meaning as set forth below, except to the extent that the context in which they are used, indicate otherwise.
Available phosphate: The term “available phosphate” refers to the phosphate content that is soluble in water and citrate solution.
Available potassium: The term “available potassium” refers to the potassium content that is soluble in water.
Biological yield: The term “biological yield” refers to the total amount of plant material produced by a crop.
Digestate powder: The term “digestate powder” refers to a powder that is sourced from biogas plant.
Flocculating agent: The term “flocculating agent” refers to a chemical additive that causes suspended solids to clump together into larger particles, or flocs.
Grain yield: The term “grain yield” refers to the amount of grains produced by a crop, such as wheat or rice, per unit area of land.
Straw yield: The term “straw yield” refers to the amount of dry stalks and leaves left after harvesting a crop.
Test weight per 1000 seeds: The term “test weight per 1000 seeds” refers to the weight of a specific quantity (1000 seeds) of a particular seed variety, typically measured in grams. Test weight is an indicator of seed quality (density or bulkiness of the seeds), seed viability, and overall performance (seed size, health, and maturity) in planting and crop production. A higher test weight generally indicates larger, denser, and healthier seeds, while a lower test weight could suggest the presence of smaller or less-developed seeds.
BACKGROUND
The background information herein below relates to the present disclosure but is not necessarily prior art.
Cattle dung is widely used as a fertilizer and as a fuel. Direct burning of dried cattle dung emits a lot of gaseous and solid waste material which leads to pollution. Biogas preparation from cattle dung by the inherently present microorganisms is another method being used generally for the preparation of fertilizer or fuel. In the process of preparing the biogas, the cattle dung is mixed with water and left for anaerobic digestion to produce bio-methane. The digested semi-solid slurry obtained from the biogas plant as a by-product is then used as a fertilizer.
Handling and application of the so-obtained semi-solid slurry when used as fertilizer has numerous disadvantages such as non-uniform distribution of nutrients, spillage loss, leaching loss and the like. Further, conventional solid fertilizers prepared from cattle dung lacks the required essential nutrients, resulting in lack of ability to resist against diseases, disorders and/or unfavorable conditions, and leading to poor yield. Further, addition of chemicals for controlling diseases and growth may be harmful to plants, soil and nature.
Therefore, there is felt a need to provide a granular fertilizer and a process for its preparation, that alleviates the aforementioned drawbacks, or at least provide a useful alternative.
OBJECTS
Some of the objects of the present disclosure, which at least one embodiment herein satisfies, are as follows:
It is an object of the present disclosure to ameliorate one or more problems of the background or to at least provide a useful alternative.
An object of the present disclosure is to provide a granular fertilizer.
Another object of the present disclosure is to provide a granular fertilizer that utilizes digestate obtained from a cattle dung biogas plant.
Still another object of the present disclosure is to provide a granular fertilizer that has essential nutrients for plant growth and development.
Yet another object of the present disclosure is to provide a granular fertilizer that is devoid of harmful chemicals.
Still another object of the present disclosure is to provide a process for the preparation of a granular fertilizer.
Still another object of the present disclosure is to provide a process for the preparation of a granular fertilizer that is simple, environmental friendly and economical.
Other objects and advantages of the present disclosure will be more apparent from the following description, which is not intended to limit the scope of the present disclosure.
SUMMARY
The present disclosure relates to a granular fertilizer. The granular fertilizer comprises a homogenized mixture of 45 mass% to 70 mass% of digestate powder, 25 mass% to 50 mass% of rock phosphate powder, 0.5 mass% to 15 mass% of protein hydrolysate, and at least one bacterium having bacterial count in the range of 107 CFU per gram to 1010 CFU per gram with respect to the total amount of the granular fertilizer.
In accordance with the present disclosure, the fertilizer has size in the range of 0.5 mm to 5 mm, crushing strength in the range of 0.6 kg per granule to 3 kg per granule, bulk density in the range of 0.5 g/cc to 1.6 g/cc, carbon to nitrogen ratio in the range of 15:1 to 22:1.
In accordance with the present disclosure, the granular fertilizer has available phosphate in the range of 8% w/w to 15% w/w; available potassium content in the range of 0.5 % w/w to 2 % w/w; the total nitrogen content is in the range of 0.4% w/w to 1.5% w/w, and total organic carbon content in the range of 8% w/w to 24% w/w.
In accordance with the present disclosure, a source of the digestate powder is separated solids from bio-slurry of cattle dung based biogas plant.
In accordance with an embodiment of the present disclosure, the bacterium is at least one selected from the group consisting of nitrogen fixation bacterium, phosphorus solubilizing bacterium, and potassium mobilizing bacterium.
In accordance with an embodiment of the present disclosure, the protein hydrolysate is selected from cereal protein hydrolysate and soy protein hydrolysate.
The present disclosure also relates to a process for preparing a granular fertilizer. The process comprises obtaining a biogas plant digestate slurry. A predetermined amount of a flocculating agent is mixed to the digestate slurry under stirring for a first predetermined time period followed by filtration to obtain a separated semi-solid digestate and a liquid portion. The separated semi-solid digestate is dried for a second predetermined time period to obtain the semi-dried mass with reduced moisture content. The semi dried mass is crushed to obtain a powder having a predetermined particle size. The predetermined amounts of rock phosphate powder, at least one bacterium culture, and protein hydrolysate are added to the powder to obtain a mixture, followed by homogenizing the mixture to obtain a homogenized mixture. The homogenized mixture is then granulated to obtain wet granules. The wet granules are dried at a predetermined temperature for a third predetermined time period to obtain the granular fertilizer.
In accordance with the present disclosure, a source of the digestate slurry is separated solids from a bio-slurry of a cattle dung based biogas plant.
In accordance with an embodiment of the present disclosure, the first predetermined time period is in the range of 2 minutes to 40 minutes, the second predetermined time period is in the range of 10 hours to 40 hours, the predetermined particle size is in the range of 50 µm to 200 µm, the predetermined temperature is in the range of 40 °C to 80 °C, and the third predetermined time period is in the range of 10 minutes to 30 minutes.
In accordance with an embodiment of the present disclosure, the predetermined amount of the flocculating agent is in the range of 0.01 mass% to 0.2 mass% with respect to the total amount of the digestate slurry, the predetermined amount of the rock phosphate powder is in the range of 25 mass % to 50 mass % with respect to the total amount of the granular fertilizer, the predetermined amount of the bacterium culture is in the range of 107 CFU per gram with respect to the total amount of the granular fertilizer to 1010 CFU per gram with respect to the total amount of the granular fertilizer, the predetermined amount of the protein hydrolysate is in the range of 0.5 mass % to 15 mass % with respect to the total amount of the granular fertilizer.
In accordance with an embodiment of the present disclosure, the flocculating agent is selected from the group consisting of polyelectrolyte, carboxy methyl cellulose and polylignin flocculent.
In accordance with an embodiment of the present disclosure, the bacterium culture is at least one selected from the group consisting of nitrogen fixation bacterium, phosphorus solubilizing bacterium, and potassium mobilizing bacterium.
In accordance with an embodiment of the present disclosure, the protein hydrolysate is selected from cereal protein hydrolysate and soy protein hydrolysate.
In accordance with an embodiment of the present disclosure, the separated semi-solid digestate has a moisture content in the range of 35% to 82%; and the semi-dried mass has a moisture content in the range of 15% to 42%.
DETAILED DESCRIPTION
The present disclosure relates to fertilizer.
Embodiments are provided so as to thoroughly and fully convey the scope of the present disclosure to the person skilled in the art. Numerous details are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present disclosure. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present disclosure. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.
The terminology used, in the present disclosure, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present disclosure. As used in the present disclosure, the forms "a,” "an," and "the" may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms "comprises," "comprising," “including,” and “having,” are open ended transitional phrases and therefore specify the presence of stated features, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, elements, components, and/or groups thereof.
The terms first, second, third, etc., should not be construed to limit the scope of the present disclosure as the aforementioned terms may be only used to distinguish one element, component, region, layer or section from another component, region, layer or section. Terms such as first, second, third etc., when used herein do not imply a specific sequence or order unless clearly suggested by the present disclosure.
As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed elements.
The digestate obtained from the cattle dung based biogas plant has various challenges in utilizing it as a fertilizer. These challenges are no uniform distribution of nutrients, spillage loss, leaching loss, and the like. Efficient re-use of such natural mature that can further be sustainably and efficiently used in agriculture is required.
Further, the cattle dung-based fertilizers presently available in the market do not contain sufficient nutrients and minerals for healthy plant growth and development. At the same time, most of the conventional and popular fertilizers available in market are chemical-based. These chemicals are expensive, and may harm plants, soil and nature.
The present disclosure provides a granular fertilizer and a process for its preparation.
In an aspect, the present disclosure provides a granular fertilizer. The fertilizer comprises a homogenized mixture of 45 mass% to 70 mass% of a digestate powder, 25 mass% to 50 mass% of rock phosphate powder, 0.5 mass% to 15 mass% of protein hydrolysate, and at least one bacterium having bacterial count in the range of 107 CFU per gram to 1010 CFU per gram with respect to the total amount of the granular fertilizer.
In an exemplary embodiment, the granular fertilizer comprises a homogenized mixture of 50 mass% digestate powder, 40 mass% rock phosphate powder, 10 mass% protein hydrolysate, and at least one bacterium having bacterial count of 108 CFU per gram with respect to the total amount of the granular fertilizer.
In another exemplary embodiment, the granular fertilizer comprises a homogenized mixture of 55 mass% digestate powder, 44 mass% rock phosphate powder, 1 mass% protein hydrolysate, and at least one bacterium having bacterial count of 108 CFU per gram of the granular fertilizer. In accordance with the present disclosure, a source of the digestate powder is separated solids from a bio-slurry of a cattle dung based biogas plant.
The digestate from the cattle dung biogas plant is a commonly used organic fertilizer. In the biogas plant, the microbes already present in the cattle dung breaks down the organic matter during anaerobic digestion to form the digestate. The digestate is rich in fertilizer properties for plant growth and development. The digestate improves both plant growth and soil health. Nitrogen is inherently present in the digestate.
Rock phosphate is responsible for healthy root growth, early shoot growth, and seed formation. It improves the overall quality of the seed, grain, fruit and/or vegetable. It increases nutrient levels such as of calcium, magnesium, and the like, and also increases the carbon accumulation.
In accordance with an embodiment of the present disclosure, the protein hydrolysate is selected from cereal protein hydrolysate and soy protein hydrolysate. In accordance with the present disclosure, the cereal protein hydrolysate is selected from wheat protein hydrolysate, rice protein hydrolysate, oats protein hydrolysate, and maize protein hydrolysate. In an exemplary embodiment, the cereal protein hydrolysate is maize protein hydrolysate.
In an embodiment, the maize protein hydrolysate contains 2.5 % nitrogen, 0.5 % w/w ammonical nitrogen, 12 % hydrolyzed protein, 1 % w/w each of amino acids such as glutamic acid, serine, leucine, alanine, and pH in the range of 1 to 1.2.
Protein hydrolysate improves growth and development of plant roots and also improves overall health of the plant. Protein hydrolysate improves surface area of the root and its length, which in turn results in efficient nutrient, mineral and water intake to provide resistance to plants during adverse conditions.
In accordance with an embodiment of the present disclosure, the bacterium is at least one selected from the group consisting of nitrogen fixing bacterium, phosphorus solubilizing bacterium, and potassium mobilizing bacterium.
The commonly used nitrogen fixing bacterium are Azotobacter, Bacillus, Clostridium, and Klebsiella. They supply essential assimilative nitrogen to the plants that are present in an un-absorbable form in the air. Nitrogen is important for the synthesis of proteins by the plants.
Phosphorus solubilizing bacterium are beneficial bacterium capable of solubilizing inorganic phosphorus from insoluble compounds. Some examples of phosphorus solubilizing bacterium are Pseudomonas, Bacillus, Micrococcus, Aspergillus, and Fusarium.
Potassium mobilizing bacterium such as B. mucilaginosus, B. edaphicus, B. circulans, Pseudomonas, Burkholderia, Acidithiobacillus ferrooxidans, and Paenibacillus spp. solubilize inorganic potassium from insoluble compounds and provide them for plant intake. These microorganisms are also referred to as potassium dissolving bacterium. These microorganisms increase the resistance of crops in hot and dry condition, improve fruits/grain quality, increase sugar content and size of fruits.
In an exemplary embodiment, the nitrogen fixation bacterium is Azotobacter, the phosphorus solubilizing bacterium is Bacillus, and the potassium mobilizing bacterium is Paenibacillus spp.
In accordance with the present disclosure, the granular fertilizer has size is in the range of 0.5 mm to 5 mm. In an exemplary embodiment, the granular fertilizer has the size of 3.2 mm. As per Fertilizer Control Order (FCO), minimum 90% material should pass through 4.0 mm sieve.
In accordance with the present disclosure, the granular fertilizer has crushing strength is in the range of 0.6 kg per granule to 3 kg per granule. In an exemplary embodiment, the granular fertilizer has the crushing strength of 2.1 kg per granule. In another exemplary embodiment, the granular fertilizer has the crushing strength of 2.64 kg per granule.
In accordance with the present disclosure, the granular fertilizer has bulk density is in the range of 0.5 g/cc to 1.6 g/cc. In an exemplary embodiment, the granular fertilizer has the bulk density of 0.64 g/cc. In another exemplary embodiment, the granular fertilizer has the bulk density of 0.8 g/cc. In still another exemplary embodiment, the granular fertilizer has the bulk density of 0.76 g/cc. In an embodiment, the granular fertilizer has the bulk density of 1.2 g/cc.
The size of the granular fertilizer in the range of 0.5 mm to 5 mm gives convenience in application by broadcasting or other means, as uniform distribution can be achieved. Homogeneity in nutrient content also is achieved by granulation in this size. The granules are having crushing strength in the range of 0.6 kg per granule to 3 kg per granule, reducing the possibility of powdering or aberration during storage and handling. Organic manure influences the bulk density of soil. A low bulk density of soil indicates more porous structure, more water penetration and more aeration, enhancing root growth. Organic fertilizer granules with low bulk density are expected to help improve the water holding capacity, aeration, and microbial activity of soil. The bulk density in the range of 0.5 g/cc to 1.6 g/cc is hence expected to improve soil physical properties.
In accordance with the present disclosure, the granular fertilizer has carbon to nitrogen ratio in the range of 15:1 to 22:1. In an exemplary embodiment, the granular fertilizer has the carbon to nitrogen ratio of 19:1. In another exemplary embodiment, the granular fertilizer has the carbon to nitrogen ratio of 18:1. In yet another exemplary embodiment, the granular fertilizer has the carbon to nitrogen ratio of 20:1.
In accordance with the present disclosure, the fertilizer has an available phosphate content in the range of 8 %w/w to 15 %w/w. The available phosphate can be, but not necessarily measured in terms of phosphorous pentoxide (P2O5). The available phosphate is the phosphate in plant available form. In an exemplary embodiment, the available phosphate content is 13 %w/w. In another exemplary embodiment, the available phosphate content is 8 %w/w. In still another exemplary embodiment, the available phosphate content is 9.5 %w/w.
The phosphorous pentoxide (P2O5) plays an important role in energy transfer and storage, photosynthesis, as well as in the transformation of sugar and starch. It is responsible for overall plant health and development, specifically during early stages of growth. It also helps maintaining soil fertility and quality.
In accordance with the present disclosure, the fertilizer has the available potassium content in the range of 0.5% w/w to 2% w/w. The available potassium content can be, but not necessarily measured in terms of potassium oxide (K2O). The available potassium is the potassium in plant available form. In an exemplary embodiment, the fertilizer has the available potassium content of 0.42% w/w. In another exemplary embodiment, the fertilizer has the available potassium content of 0.74% w/w. In still another exemplary embodiment, the fertilizer has the available potassium content of 1% w/w.
In accordance with the present disclosure, the fertilizer has a total nitrogen content in the range of 0.4% w/w to 1.5% w/w. In an exemplary embodiment, the fertilizer has a total nitrogen content of 1.05% w/w. In another exemplary embodiment, the fertilizer has a total nitrogen content of 0.84% w/w. In still another exemplary embodiment, the fertilizer has a total nitrogen content of 1.23% w/w. In yet another exemplary embodiment, the fertilizer has a total nitrogen content of 0.76% w/w.
In accordance with the present disclosure, the fertilizer has a total organic carbon content is in the range of 8% w/w to 24% w/w. In an exemplary embodiment, the fertilizer has the total organic carbon content of 19.73 %w/w. In another exemplary embodiment, the fertilizer has the total organic carbon content of 15.54% w/w. In still another exemplary embodiment, the fertilizer has the total organic carbon content of 22.36% w/w.
The granular fertilizer of the present disclosure is easy to handle and transport from one place to another.
In another aspect, the present disclosure provides a process for preparing granular fertilizer. The process comprises the following steps:
A biogas plant digestate slurry is obtained.
In accordance with the present disclosure, a source of the digestate slurry is separated solids from a bio-slurry of a cattle dung based biogas plant.
In an embodiment, the digestate slurry is a remaining digestate obtained from cattle dung-based biogas plant. The biogas plant utilizes anaerobic bacteria in the cattle dung for assimilation and digestion. The resultant digestate slurry of biogas plant contains 5% to 20 % solid and the remaining liquid contains dissolved nutrients.
A predetermined amount of a flocculating agent is mixed to the digestate slurry under stirring for a first predetermined time period, followed by filtration to obtain a separated semi-solid digestate and a liquid portion.
In accordance with an embodiment of the present disclosure, the flocculating agent is selected from the group consisting of polyelectrolyte, carboxy methyl cellulose, and polylignin flocculant. In an exemplary embodiment, the flocculating agent is polyelectrolyte.
In accordance with an embodiment of the present disclosure, the predetermined amount of the flocculating agent is in the range of 0.01 mass % to 0.2 mass % with respect to the total amount of the digestate slurry. In an exemplary embodiment, amount of the flocculating agent is 0.03 mass % with respect to the total amount of the digestate slurry.
In accordance with an embodiment of the present disclosure, the first predetermined time period is in the range of 2 minutes to 40 minutes. In an exemplary embodiment, the first predetermined time period is 3 minutes.
In an embodiment, the filtration is performed through a screw filtration unit to separate the liquid portion from the semi-solid digestate. The liquid portion is stored for further quality improvement and application as liquid fertilizer.
In an embodiment, the separated semi-solid digestate has a moisture content in the range of 35% to 82%. In an exemplary embodiment, the moisture content of the separated semi-solid digestate is 80 %.
The separated semi-solid digestate is dried for a second predetermined time period to obtain the semi-dried mass having reduced moisture content.
In accordance with an embodiment of the present disclosure, the second predetermined time period is in the range of 10 hours to 40 hours. In an exemplary embodiment, the second predetermined time period is 36 hours. In an embodiment, the second predetermined time is 12 hours.
In an embodiment, the separated solid digestate is dried in an oven at a temperature in the range of 65 oC to 70 oC for time period in the range of 10 hours to 15 hours to obtain the semi-dried mass. In another embodiment, the separated solid digestate is sun-dried for a time period in the range of 12 hours to 40 hours.
In accordance with the embodiments of the present disclosure, the semi-dried mass has a moisture content in the range of 15% to 42%. In an exemplary embodiment, the semi-dried mass has a moisture content of 40%.
The semi-dried mass is crushed to obtain a powder having a predetermined particle size.
In accordance with an embodiment of the present disclosure, the predetermined particle size of the crushed powder is in the range of 50 µm to 200 µm. In an exemplary embodiment, the predetermined particle size is 90 µm. The semi-dried mass is crushed for evenness.
In an embodiment, the crushing is done with the help of a pulveriser.
The predetermined amounts of rock phosphate powder, at least one bacterium culture, and protein hydrolysate are added to the powder to obtain a mixture, followed by homogenizing the mixture to obtain a homogenized mixture.
In accordance with an embodiment of the present disclosure, the predetermined amount of the rock phosphate powder is in the range of 25 mass % to 50 mass % with respect to the total amount of the granular fertilizer. In an exemplary embodiment, amount of the rock phosphate powder is 40 mass % with respect to the total amount of the granular fertilizer. In another exemplary embodiment, amount of the rock phosphate powder is 44 mass % with respect to the total amount of the granular fertilizer.
In accordance with an embodiment of the present disclosure, the bacterium culture is at least one selected from the group consisting of nitrogen fixation bacterium, phosphorus solubilizing bacterium, and potassium mobilizing bacterium. In an exemplary embodiment, the nitrogen fixation bacterium is Azotobacter, the phosphorus solubilizing bacterium is Bacillus, and the potassium mobilizing bacterium is Paenibacillus spp.
In accordance with an embodiment of the present disclosure, the predetermined amount of the bacterium culture is in the range of 107 CFU per gram with respect to the total amount of granular fertilizer to 1010 CFU per gram with respect to the total amount of the granular fertilizer. In an exemplary embodiment, amount of each bacterium culture is 108 CFU per gram with respect to the total amount of the granular fertilizer.
In accordance with an embodiment of the present disclosure, the protein hydrolysate is selected from cereal protein hydrolysate and soy protein hydrolysate. In an embodiment, the cereal protein hydrolysate is selected from the group consisting of wheat protein hydrolysate, rice protein hydrolysate, oats protein hydrolysate, and maize protein hydrolysate. In an exemplary embodiment, the protein hydrolysate is maize protein hydrolysate.
In accordance with an embodiment of the present disclosure, the predetermined amount of the protein hydrolysate is in the range of 0.5 mass % to 15 mass % with respect to the total amount of the granular fertilizer. In an exemplary embodiment, the amount of the protein hydrolysate is 1 mass % with respect to the total amount of the granular fertilizer. In another exemplary embodiment, the amount of the protein hydrolysate is 10 mass% with respect to the total amount of the granular fertilizer.
In accordance with an embodiment of the present disclosure, the homogenized mixture has a moisture content is in the range of 22 % to 25 %. In an exemplary embodiment, the homogenized mixture has a moisture content is 24 %.
The homogenized mixture is then granulated to obtain wet granules.
In an embodiment, granulation is performed by using an extruder granulator.
The wet granules are dried at a predetermined temperature for a third predetermined time period to obtain the granular fertilizer.
In accordance with the present disclosure, the predetermined temperature is in the range of 40 °C to 80 °C. In an exemplary embodiment, the predetermined temperature is 70 oC.
In accordance with an embodiment of the present disclosure, the third predetermined time period is in the range of 10 minutes to 30 minutes. In an exemplary embodiment, the third predetermined time period is 25 minutes.
The granular fertilizer of the present disclosure is an effective source of assimilable nutrients for all types of growing plants. The fertilizer additionally improves soil structure and regenerates the soil fertility.
The process for preparing the granular fertilizer of the present disclosure is sustainable, efficient, and economical. The process utilizes natural organic manure, thus contributing to sustainable system, healthy soil, plant, and thus a healthy environment. The process of the present disclosure is simple and easy.
The foregoing description of the embodiments has been provided for purposes of illustration and not intended to limit the scope of the present disclosure. Individual components of a particular embodiment are generally not limited to that particular embodiment, but, are interchangeable. Such variations are not to be regarded as a departure from the present disclosure, and all such modifications are considered to be within the scope of the present disclosure.
The present disclosure is further illustrated herein below with the help of the following experiments. The experiments used herein are intended merely to facilitate an understanding of the ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the experiments should not be construed as limiting the scope of embodiments herein. These laboratory scale experiments can be scaled up to industrial/commercial scale and the results obtained can be extrapolated to industrial/commercial scale.
EXPERIMENTAL DETAILS:
Process for the preparation of a granular fertilizer in accordance with the present disclosure
Maize protein hydrolysate was procured from M/s Pushpa J Shah, GIDC Ankleshwar, Gujarat. Nitrogen fixation bacteria Azotobacter, phosphorous solubilizing bacteria Bacillus, and potash mobilizing bacteria Paenibacillus spp. were obtained from in-house production plant of Gujarat State Fertilizers and Chemicals Limited, Vadodara, Gujarat.
Example 1
500 kg of digestate slurry was obtained from the cattle dung-based biogas plant. To the slurry, 50 liters of a polyelectrolyte solution (having 150 g of polyelectrolyte) was added under stirring for 3 minutes, followed by screw filtration to obtain a semi-solid digestate and a liquid portion. The separated semi-solid digestate had 80% moisture content. The solid digestate was sun-dried for 36 hours to obtain 250 kg of semi-dried mass having around 40% moisture content. The semi-dried mass was crushed to obtain a powder having a particle size of 90 µm. To the crushed powder, 80 kg rock phosphate, 400 ml nitrogen fixation bacteria broth containing 108 CFU, 400 ml phosphorous solubilizing bacteria broth containing 108 CFU, 400 ml potash mobilizing bacteria broth containing 108 CFU, and 2 kg maize protein hydrolysate were added to obtain a mixture.
The rock phosphate contained 18 % P2O5, and each broth contained a CFU value of the order of 108 per gram. Maize protein hydrolysate is one of the cereal protein hydrolysate (CPH). The specification of the maize protein hydrolysate is as shown in Table 1.
Table 1: Specification of the maize protein hydrolysate in accordance with the present disclosure
Parameters Specification*
Total nitrogen 2.5 % w/w (min.)
Ammonical nitrogen 0.5 % w/w (max.)
Hydrolyzed protein 12 % w/w (min.)
Amino gram
(glutamic acid, serine, leucine, alanine) > 1 % w/w each
pH 1 to 1.2
*All the analyses were performed as per Fertilizer Control Order 1985 of Government of India, updated time to time
Further, the mixture was homogenized for 30 minutes to obtain a homogenized mixture having 24% moisture content. The homogenized mixture was then granulated in an extrusion granulator of 100 kg/hour capacity to obtain wet granules. The wet granules were further sieved to obtain granules having 2.5 mm to 4 mm in size. At last, the wet granules were dried in a rotating drum dryer equipped with a hot air blower with a contact temperature of 70 °C for 25 minutes to obtain the granular fertilizer. The so obtained granular fertilizer of the present disclosure had a particle size of 3.2±0.75 mm.
Examples 2 to 6
The experimental steps of Examples 2 to 6 were performed by following the similar procedure as provided in Example 1, except the amounts of ingredients used, which are provided in Table 2.
Table 2: Composition of the granular fertilizer in accordance with the present disclosure
Examples Solid Fraction
from Biogas Slurry (Crushed digestate powder)
(in Tons) Rock Phosphate
(in Tons) NPK Consortia
(in Liters) CPH*
(in Tons) Total Weight of
Granular Fertilizer
(in Tons)
1 0.1 0.08 1.2 0.02 0.2
2 16.7 13.3 66.7 0. 330 30.40
3 8.3 6.7 33.3 0.165 15.20
4 16.7 13.3 66.7 0.330 30.40
5 55.6 44.4 222.2 1.100 101.32
6 69.4 55.6 277.8 1.375 126.65
*CPH: cereal protein hydrolysate, NPK: Nitrogen phosphorous potassium

Specifications of the granular fertilizer of the present disclosure is as given in Table 3.
Examples TOC
(% w/w) pH
(1:5 solution) EC
(dS/m) Total N
(% w/w) Total P2O5
(% w/w) K2O (% w/w) C: N ratio Moisture
(% w/w) Bulk Density (g/cm3) Crushing Strength (kg/granule)
1 19.73 7.80 2.83 1.05 13.03 0.42 18.80:1 7.4 0.80 2.05
2 18.51 7.57 1.667 0.91 8.49 0.74 20:1 5.23 0.80 2.10
3 22.36 7.25 1.776 1.23 8.01 0.79 18:1 6.25 0.80 2.1
4 17.63 7.80 1.512 0.84 9.18 0.76 21:1 4.93 0.80 2.3
5 15.54 7.71 1.609 0.76 9.73 0.74 20:1 7.26 0.76 2.64
6 17.91 7.70 1.467 0.94 8.51 1 19:1 7.36 0.64 2
Table 3: Specifications of the granular fertilizer of the present disclosure
TOC: Total organic carbon; EC: Electrical conductivity; All the analyses were performed as per Fertilizer Control Order 1985 of Government of India, updated time to time
The product was dried at the end to reduce the moisture content. If not dried, the crushing strength cannot be achieved. If completely dried, the bacteria cannot survive. Hence, the preferred moisture content value of around 8% were desired.
The granular fertilizers of the present disclosure were compared with the conventional fertilizer and the commercially available fertilizers, and the results are provided below.
Effect of the granular fertilizers of the present disclosure on vegetative growth and yield attributes of wheat crop
Field experiments were conducted in a Randomized Block Design with 6 treatments and 4 replications. Wheat crop variety used was Research Parikh Sharbati (Parikh Seeds Pvt. Ltd.), plot size used was (L*W) 4*3 = 12 m2 (L: Length, W: Width), spacing (R*R) was 45*45 cm (Row to Row), wheat seed rate application was 150 gm/12 m2 plot.
According to soil analysis report, the recommended dose of fertilizer (RDF)/acre was Nitrogen (48 kg/acre), and Phosphate (28 kg/acre).
Fertilizer used for trial were: (1) diammonium phosphate (DAP) having phosphate content 46 %, and nitrogen content of 18 %, (2) urea having nitrogen content of 46%, and (3) the granular fertilizer of the present disclosure had phosphate content of 8%. The treatment details are given in Table 4.
Table 4: Various treatment trials to study the effect of the granular fertilizers on vegetative growth and yields
T1 100 % RDF (DAP and Urea)
T2 75 % RDF and 25% granular fertilizer of the present disclosure (80.93 kg/acre)
T3 75 % RDF and 25% granular fertilizer of the present disclosure (40.50 kg/acre)
T4 100 % phosphate through granular fertilizer of the present disclosure, and 100 % nitrogen through urea
T5 75 % RDF and 25% granular fertilizer of the present disclosure (25.29 kg/acre)
T6 Absolute control
RDF – Recommended dose of fertilizer, DAP - Diammonium phosphate
Table 5 illustrates dose rates application of the granular fertilizer of the present disclosure and recommended dose of fertilizer (RDF) in wheat crop trial.
Table 5: Dose rates application of the granular fertilizer of the present disclosure and recommended dose of fertilizer (RDF) in wheat crop trial
Sr. No. Treatments Required quantity of material for 12 m2 plot
RDF dose rate (gm)/12 m2 plot
DAP Granular fertilizer Urea
basal Urea
at 20 DAS
T1 100 % RDF (DAP and Urea) 180.40 - 84.06 154.63
T2 75 % RDF and 25% granular fertilizer (80.93 kg/acre) 135.30 239.88 62.96 115.92
T3 75 % RDF and 25% ranular fertilizer (40.50 kg/acre) 135.30 120.08 62.964 115.92
T4 100 % phosphate through granular fertilizer and 100 % nitrogen through urea - 1.037 154.56 154.56
T5 75 % RDF and 25% granular fertilizer (25.29 kg/acre) 135.30 74.98 62.96 115.92
T6 Absolute Control - - - -
DAP – Diammonium phosphate, RDF – recommended dose of fertilizer; DAS – Day after sowing
Table 6 illustrates initial and after crop harvest soil properties of the experimental site according to soil testing report.
Table 6: Initial and after crop harvest soil properties of the experimental site according to soil testing report
Treatments TOC
% P2O5 (kg /acre) K2O (kg /acre) pH (1:2) EC (1:2) S (ppm) Zinc
(ppm) Iron (ppm) Manganese
(ppm) Copper
(ppm)
Initial soil status
- 0.65 9.00 82.00 7.70 0.36 8.00 0.49 1.30 5.20 0.51
After crop harvest soil status
T1 0.65 07.00 176 7.55 0.35 09.60 0.74 10.61 07.90 2.04
T2 0.89 10.00 196 7.45 0.41 08.80 0.65 10.31 10.10 2.03
T3 0.70 11.00 200 7.21 0.34 07.40 0.81 13.00 15.31 2.28
T4 0.62 07.00 210 7.40 0.28 08.80 0.75 12.45 09.81 2.17
T5 0.67 10.00 206 7.24 0.28 09.20 1.08 12.15 12.44 1.74
T6 1.22 09.00 224 7.68 0.42 10.80 0.88 10.67 09.75 1.87
Average 0.89 9.10 193.20 7.35 4.39 9.89 0.81 12.59 10.92 2.03
TOC: Total organic carbon content
It can be observed that the soil status was improved in terms of total organic carbon content, phosphate content, potassium content, zinc content, iron content, manganese content, and copper content after crop harvest when the crops were treated.
Measurement of various parameters after various treatment trials are illustrated in Table 7.
Table 7: Measurement of various parameters after various treatment trials
Treatments Plant height (cm) at harvest stage No. of effective tillers/ meter row Spike length (cm) Spike weight (gm) Test weight/ 1000 seed (gm) Straw yield kg/12 m2 Grain yield kg/12 m2 plot Biological yield (kg)/12 m2 plot Harvest index %
T1 65.00 161.33 8.69 1.85 30.26 6.27 3.86 10.13 38.00
T2 68.60 191.00 8.74 2.15 32.91 6.84 4.50 11.34 39.64
T3 67.40 155.67 8.63 1.97 31.76 5.75 3.01 8.76 34.69
T4 68.35 167.33 8.40 1.83 30.02 6.01 4.17 10.18 41.09
T5 66.70 163.00 8.34 1.96 32.34 6.18 2.59 8.76 29.54
T6 60.35 120.67 7.24 1.43 29.43 3.03 1.55 4.58 33.47
Average 66.07 159.83 8.34 1.87 31.12 5.68 3.28 8.96 36.07
SE(m) 1.119 8.38 0.29 0.11 0.53 0.31 0.24 0.33 2.48
C.D. at 5% 3.405 26.76 0.93 0.34 1.70 1.00 0.75 1.06 NS
C.V. 3.388 9.56 6.04 10.00 2.96 9.53 12.43 6.41 11.92
CD- Critical difference, CV- Coefficient of variation
Harvest Index was calculated using Eq. (1):
Harvest Index %= (Total grain yield/biological yield) x 100 ……………… Eq. (1)
The maximum plant height (68.60 cm) at harvesting stage of wheat crop plant was recorded under treatment T2 and followed by treatment T4. Among the treatments, maximum number of effective tillers per meter row (191.00) at before harvest stage of wheat crop plant was recorded under treatment T2 and followed by treatment T4. The maximum spike length (8.74 cm) was recorded under treatment T2 and followed by treatment T1 only. The maximum weight of spike (2.17 gm) was recorded under treatment T2 and followed by treatment T3.
Among the treatments, test weight per 1000 seed weight (32.91) was recorded under treatment T2 and followed by treatment T5. The maximum wheat crops biological yield (11.343 kg/12 m2 plot) was recorded under treatment T2 and followed by treatment T4. The maximum wheat crop grain yield (4.501 kg/12 m2 plot) was recorded under treatment T2 and followed by treatment T4. The maximum harvest index % of wheat crop (41.09 % /12 m2 plot) was recorded under treatment T4 and followed by treatment T2.
Based on the data analysis and the conclusions of the trials of the experiment of Rabi season on wheat crop, it can be concluded that treatment T2 was found beneficial in enhancing the growth of the crop, test weight and yield of wheat seed. The treatment T2 and treatment T4 increased maximum wheat grain yield and biological yield. The soil chemical properties such as carbon content, phosphorous content, potassium content, pH, electrical conductivity (E.C.), and micronutrients remained unaltered due to application of the granular fertilizer of the present disclosure.
The granular fertilizer of the present disclosure reduces the use of DAP and urea, and provide better results when combined with DAP and urea (treatment T2 and T4).
Effect of the granular fertilizers of the present disclosure and the commercially available fertilizer on vegetative growth and yield attributes of wheat crop
Field experiments were conducted in a Randomized Block Design (RBD) with 10 treatments and 3 replications.
For these experiments, the granular fertilizer of the present disclosure was compared with a commercially available fertilizer GSFC PROMTM. Wheat crop variety used was Research Parikh Sharbati (Parikh Seeds Pvt. Ltd.), plot size (L*W) was 4*3 = 12 m2 (L: Length, W: Width), spacing (R*R) was 45x45 cm (Row to Row), wheat seed rate application was 150 gm/12 m2 plot. According to soil analysis report (iv) and recommended dose of fertilizer (RDF)/acre: - nitrogen (48 kg/acre), phosphate (28 kg/acre), and potassium (0 Kg/ acre).
Fertilizers used for trials were: (i) diammonium phosphate (DAP) having phosphate content 46%, nitrogen content 18 %, (ii) urea having nitrogen content 46%, (iii) granular fertilizer of the present disclosure having phosphate content of 8%, and (iv) commercially available GSFC PROM having phosphate content 8%. Table 8 illustrates treatment details of various trails.
Table 8: Treatment details of various trials
Treatments Details
T1 100 % RDF (DAP and Urea)
T2 75 % RDF and 25% granular fertilizer (80.93 kg/acre)
T3 75 % RDF and 25% GSFC PROMTM (80.93 kg/acre)
T4 75 % RDF and 25% granular fertilizer (40.50 kg/acre)
T5 75 % RDF and 25% GSFC PROMTM (40.50 kg/acre)
T6 100 % phosphate through granular fertilizer and 100 % N through urea
T7 100 % phosphate through GSFC PROMTM and 100 % nitrogen through urea
T8 75 % RDF and 25% granular fertilizer (25.29 kg/acre)
T9 75 % RDF and 25% GSFC PROMTM (25.29 kg/acre)
T10 Absolute control
RDF – Recommended dose of fertilizer, DAP – Diammonium phosphate
Table 9 illustrates dose rates application of the granular fertilizer of the present disclosure, GSFC PROMTM and RDF in wheat crop trial.
Table 9: Dose rates application of the granular fertilizer of the present disclosure, GSFC PROMTM and RDF in wheat crop trial
Treatments Required quantity of material for 12 m2 plot
RDF* dose rate (gm.)/12 m2 plot
DAP PROMTM Granular fertilizer of the present disclosure Urea
basal Urea
at 20 DAS
T1 180.40 - - 84.06 154.63
T2 135.30 - 239.88 62.96 115.92
T3 135.30 239.88 - 62.96 115.92
T4 135.30 - 120.08 62.964 115.92
T5 135.30 120.08 - 62.964 115.92
T6 - - 1.037 154.56 154.56
T7 - 1.037 - 154.56 154.56
T8 135.30 - 74.98 62.96 115.92
T9 135.30 74.98 - 62.96 115.92
T10 - - - - -
DAS – days after sowing, RDF – recommended dose of fertilizer, DAP – diammonium phosphate
100 % PROMTM, 100% granular fertilizer of the present disclosure, 100 % DAP and 50 % urea as basal dose application before seed sowing time as per need above calculation according to soil testing report. Remaining 50 % urea application at 20 days after sowing.
Initial and after crop harvest soil samples collected were analyzed for pH, electrical conductivity (EC), organic carbon, available phosphate, available potassium, and micro-nutrients. The results are illustrated in Table 10.
Table 10: Initial and after crop harvest soil properties of the experimental site according soil testing report
Treatment TOC % P2O5 (kg /acre) K2O (kg /acre) pH (1:2) EC (1:2) S (ppm) Zinc
(ppm) Iron
(ppm) Manganese
(ppm) Copper
(ppm)
Initial soil status
- 0.65 9.00 82.00 7.70 0.36 8.00 0.49 1.30 5.20 0.51
After crop harvest soil status
T1 0.65 07 176 7.55 0.35 09.60 0.74 10.61 07.90 2.04
T2 0.89 10 196 7.45 0.41 08.80 0.65 10.31 10.10 2.03
T3 0.71 09 148 7.07 0.31 12.40 0.38 12.78 11.20 1.94
T4 0.70 11 200 7.21 0.34 07.40 0.81 13.00 15.31 2.28
T5 1.13 09 206 7.15 0.30 12.70 0.70 15.96 10.20 2.19
T6 0.62 07 210 7.40 0.28 08.80 0.75 12.45 09.81 2.17
T7 1.38 08 252 7.22 0.25 10.00 0.81 15.52 10.45 2.23
T8 0.67 10 206 7.24 0.28 09.20 1.08 12.15 12.44 1.74
T9 0.89 11 114 7.48 0.40 09.20 1.30 12.44 12.02 1.83
T10 1.22 09 224 7.68 0.42 10.80 0.88 10.67 09.75 1.87
Average 0.89 9.10 193.20 7.35 4.39 9.89 0.81 12.59 10.92 2.03
TOC: Total organic carbon content
Measurement of various parameters after various treatment trials are illustrated in Table 11.
Table 11: Measurement of various parameters after various treatment trials
Treatments Plant height (cm) at harvest stage No. of effective tillers/ meter row Spike length (cm) Spike weight (gm) Test weight (gm) Stover yield (kg/12 m2 plot) Grain yield (kg/12 m2 plot) Biological yield (kg)/12 m2 plot) Harvest index %
T1 65.00 161.33 8.68 1.85 30.26 6.27 3.85 10.12 38.00
T2 68.60 191.00 8.74 2.15 32.91 6.84 4.50 11.34 39.64
T3 67.70 180.67 8.48 1.89 31.05 6.29 3.00 9.30 32.61
T4 67.40 155.67 8.63 1.97 31.76 5.75 3.01 8.76 34.69
T5 67.25 157.00 8.32 1.88 31.24 6.27 2.98 9.26 32.39
T6 68.35 167.33 8.40 1.83 30.02 6.00 4.17 10.17 41.09
T7 67.45 166.67 8.70 2.17 30.13 6.51 3.09 9.61 32.52
T8 66.70 163.00 8.34 1.95 32.34 6.17 2.58 8.76 29.54
T9 66.35 157.33 8.69 2.10 32.69 5.50 1.99 7.49 27.23
T10 60.35 120.67 7.24 1.43 29.43 3.02 1.55 4.58 33.47
Average 66.52 162.07 8.42 1.92 31.18 5.86 3.07 8.94 34.11
SE(m) 1.05 8.95 0.28 0.12 0.58 0.44 0.18 0.45 2.42
C.D. 3.07 26.78 N/A 0.36 1.74 1.33 0.54 1.34 7.27
C.V. 3.17 9.56 5.95 11.062 3.23 13.16 10.23 8.69 12.33

The treatment methods were focused on the effect of the granular fertilizer of the present disclosure and GSFC phosphate rich organic manure (PROM) with 75 % RDF fertilizer basal dose was application and observed plant growth and grain yield attributes of wheat crop.
It was observed that the maximum plant height (68.60 cm) at harvesting stage of wheat crop plant was recorded under treatment T2 and followed by treatment T6. Among the treatments, maximum number of effective tillers per meter row (191.00) at before harvest stage of wheat crop plant was recorded under treatment T2 and treatment T3. The maximum spike length (8.74 cm) was recorded under treatment T2 and followed by treatment T7. The maximum weight of spike (2.17 gm) was recorded under treatment, T7 and treatment T2. Among the treatments, test weight per 1000 seed weight (32.91) was recorded under treatment, T2 and treatment T9. The maximum wheat crops biological yield (11.343 kg/12 m2 plot) was recorded under treatment T2 and treatment T6. The maximum wheat crop grain yield (4.501 kg/12 m2 plot) was recorded under treatment T2 and treatment T6. The maximum harvest index % of wheat crop (41.09 % per 12 m2 plot) was recorded under treatment T6.
The results of the experiment of Rabi season on wheat crop indicated that the treatment T2 was found beneficial in enhancing the growth of the crop, test weight and the yield of wheat seed. The treatment T2 and treatment T6, increased maximum wheat grain yield and the biological yield. The soil chemical properties (total organic carbon %, phosphate content, potassium content, pH, electrical conductivity and micronutrients remained unaltered due to application of the granular fertilizer of the present disclosure and GSFC PROMTM fertilizer products.
The granular fertilizer of the present disclosure reduces the use of DAP and urea, and provide better results when combined with DAP and urea (treatment T2 and T4). Further, the granular fertilizer of the present disclosure provides better results than the commercially available fertilizer.
TECHNICAL ADVANCEMENTS
The present disclosure described hereinabove has several technical advantages including, but not limited, the realization of, a granular fertilizer, that:
• is easy to handle and easy to transport; and
• is low in cost as it utilizes cheaper raw material;
and
a process of preparing a granular fertilizer, that:
• utilizes cheaper raw materials; and
• is simple, environment friendly and economical.
The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
The foregoing description of the specific embodiments so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge/lane, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.
Any discussion of devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge/lane in the field relevant to the disclosure as it existed anywhere before the priority date of this application.
The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.
While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation. ,CLAIMS:WE CLAIM:
1. A granular fertilizer comprising a homogenized mixture of:
(a) 45 mass% to 70 mass% a digestate powder;
(b) 25 mass% to 50 mass% of rock phosphate powder;
(c) 0.5 mass% to 15 mass% of protein hydrolysate; and
(d) at least one bacterium having bacterial count in the range of 107 CFU per gram to 1010 CFU per gram with respect to the total amount of said granular fertilizer.
2. The fertilizer as claimed in claim 1 is characterized by at least one of the following:
• size in the range of 0.5 mm to 5 mm;
• crushing strength in the range of 0.6 kg per granule to 3 kg per granule;
• bulk density in the range of 0.5 g/cc to 1.6 g/cc;
• carbon to nitrogen ratio in the range of 15:1 to 22:1;
• available phosphate content in the range of 8% w/w to 15% w/w;
• available potassium content in the range of 0.5 % w/w to 2 % w/w;
• total nitrogen content in the range of 0.4% w/w to 1.5% w/w; and
• total organic carbon content in the range of 8% w/w to 24% w/w.
3. The fertilizer as claimed in claim 1, wherein a source of said digestate powder is separated solids from bio-slurry of a cattle dung based biogas plant.
4. The fertilizer as claimed in claim 1, wherein said bacterium is at least one selected from the group consisting of nitrogen fixing bacterium, phosphorus solubilizing bacterium, and potassium mobilizing bacterium.
5. The fertilizer as claimed in claim 1, wherein said protein hydrolysate is selected from cereal protein hydrolysate and soy protein hydrolysate.
6. A process for the preparation of a granular fertilizer, said process comprising the following steps:
(i) obtaining a biogas plant digestate slurry;
(ii) mixing a predetermined amount of a flocculating agent to said digestate slurry under stirring for a first predetermined time period followed by filtration to obtain a separated semi-solid digestate and a liquid portion;
(iii) drying said separated semi-solid digestate for a second predetermined time period to obtain a semi-dried mass having reduced moisture content;
(iv) crushing said semi-dried mass to obtain a powder having a predetermined particle size;
(v) adding predetermined amounts of rock phosphate powder, at least one bacterium culture, and protein hydrolysate to said powder to obtain a mixture, followed by homogenizing said mixture to obtain a homogenized mixture;
(vi) granulating said homogenized mixture to obtain wet granules; and
(vii) drying said wet granules at a predetermined temperature for a third predetermined time period to obtain said granular fertilizer.
7. The process as claimed in claim 6, wherein a source of said digestate slurry is separated solids from a bio-slurry of a cattle dung based biogas plant.
8. The process as claimed in claim 6, wherein
• said first predetermined time period is in the range of 2 minutes to 40 minutes;
• said second predetermined time period is in the range of 10 hours to 40 hours;
• said predetermined particle size is in the range of 50 µm to 200 µm;
• said predetermined temperature is in the range of 40 °C to 80 °C; and
• said third predetermined time period is in the range of 10 minutes to 30 minutes.
9. The process as claimed in claim 6, wherein
• said predetermined amount of said flocculating agent is in the range of 0.01 mass% to 0.2 mass% with respect to the total amount of said digestate slurry;
• said predetermined amount of said rock phosphate powder is in the range of 25 mass % to 50 mass % with respect to the total amount of said granular fertilizer;
• said predetermined amount of said bacterium culture is in the range of 107 CFU per gram with respect to the total amount of the granular fertilizer to 1010 CFU per gram with respect to the total amount of the granular fertilizer; and
• said predetermined amount of said protein hydrolysate is in the range of 0.5 mass % to 15 mass % with respect to the total amount of said granular fertilizer.
10. The process as claimed in claim 6, wherein said flocculating agent is selected from the group consisting of polyelectrolyte, carboxy methyl cellulose, and polylignin flocculant.
11. The process as claimed in claim 6, wherein said bacterium culture is at least one selected from the group consisting of nitrogen fixation bacterium, phosphorus solubilizing bacterium, and potassium mobilizing bacterium.
12. The process as claimed in claim 6, wherein said protein hydrolysate is selected from cereal protein hydrolysate and soy protein hydrolysate.
13. The process as claimed in claim 6, wherein
• said separated semi-solid digestate has a moisture content in the range of 35% to 82%; and
• said semi-dried mass has a moisture content in the range of 15% to 42%.
Dated this 01st Day of January 2025

_______________________________
MOHAN RAJKUMAR DEWAN, IN/PA – 25
OF R. K. DEWAN & CO.
AUTHORIZED AGENT OF APPLICANT