**2.4 Green solution to soil pollution: DCP- agrarian booster**

Soil is a heavenly resource, a living, breathing and ever-changing dynamic ecosystem. The theory of Biorhexistasy, describes two crucial climatic phases of soil i.e., Biostasy, period of soil formation and Rhexistasy, periods of soil erosion [34]. The theory emphasizes on the role of climatic conditions that initiate pedogenesis and subsequent soil retrogression. For example, moist climates promote the chemical deterioration of rocks, leading to formation of soils and improvement in vegetation, which reflects the period of biostasy. On the other hand, dry climates and winds bring about displacement of soils and mechanical disintegration of exposed rocks, leading to the unfavorable period of rhexistasy or soil erosion and degradation. The two stages occur in cyclic form and control soil quality and vegetation. Extended periods of rhexistasy lead to ever-increasing soil degradation.

Thus, due to soil erosion, salination, and extreme acidification, large portions of arable land lose their fertility. The scale of this agrarian distress can be improved by the addition of HA, which promotes root growth and induces salt tolerance in plants, thus reversing the adverse effects of salt stress [35].

For economizing the addition of HA into soils, DCP can be used since it is freely available and inexpensive. Addition of DCP initiates the biotransformation of saline soils and enhances their humus content. Due to the rich microbial biota and chemically inert properties, DCP has been utilized as a soil conditioner and fertilizer since ancient times. Thus, we reiterate that DCP is soil's Green ambrosia and one of the best contenders for soil replenishing and rejuvenation.

### **2.5 Waste to green energy: DCP- biofuel**

As any other non-conventional and renewable green source of energy, DCP has been explored as biofuel and proves to be pseudo shale, boosting renewable energy sector. Feng et al. have developed a high-performance anode from carbonized cow dung for bio-electrochemical systems [36]. Kumar et al. found that in the generation of electricity, natural cow dung was found more suitable as it generated 150.9 mV Open Circuit Voltage (OCV) [37]. There is a review by Gupta et al., focusing on recent findings on cow dung harnessed for biofuel production and management of environmental pollutants and its usage in different areas such as medicine, agriculture, and industry [38].

### **2.6 Wastewater remediation: DCP - Humiresin**

The research work of Bagla et al., has examined and justified an innovative and concrete role of DCP in the bioremediation of toxic metal pollutants and hazardous radionuclides from the pool of various effluents using Radiotracer technique. Notable heavy metal pollutants like trivalent and hexavalent chromium, cadmium [39], mercury [40], silver [41], zinc [42] have been eliminated from aqueous systems using DCP as a biosorbent. Similarly, radionuclides commonly found in radioactive waste - 60Co, 90Sr and 137Cs [43, 44], have been removed from simulated systems of reactor and reprocessing waste.

Being freely and easily available DCP has an edge over processed natural adsorbent considering their cost, time, and energy efficiency. Also, DCP does not impart any foul odor to treated water, nor does it lead to increase in biomass, unlike other natural adsorbents. DCP used for heavy metal adsorption can be subjected

*Humic Substances*

processes.

properties.

as stress on environmental safety.

**2.3 Unearthed humus DCP- zero waste prototype**

The pedosphere or soil body is rich in organic matter, soil fauna, minerals, water,

Humus, the organic matter in soil, permits better aeration, enhances the absorption, releases nutrients, and makes the soil less susceptible to leaching and erosion, thus the agent of soil's vitality. Soils contain more organic carbon than the atmosphere and vegetation combined; therefore, mineralization of soil organic matter and release of carbon versus humification processes, could greatly affect carbon capture and stabilization, and consequently the global climate change. Carbon sequestration and storage in soils provide an important means of reducing green-

house gases in the atmosphere to mitigate predicted climate changes [28].

many different factors as HS are essentially time and climate dependent.

The aforementioned qualities of HS make it a very powerful tool not only in sustenance of WFE Nexus but its essential role in mitigation of climate change. This draws our attention towards requirement of highly appropriate method for the Selection of HS products as there are enormous variety of HS available globally. The quality and composition of any mined or extracted Humates or HS depends on

Under ideal conditions, the turnover time of organic carbon added in form of HS each year from plant and animal residues into the soil, averages approximately 30 years [29]. Due to this time constraint in production of fresh humus, we face many challenges ovulated due to multiple sites and over digging of soils. Also, soil humus development is highly affected by seasonal change, litter type and time, hot or cold climate and freeze–thaw cycle [30]. Studies by Dou et al. have explained that freeze–thaw cycles can even destroy the structure of newly formed humus [31]. Nonetheless, a good HS material can be destroyed by improper mining or processing. Hence the mining and the extraction of HS must be meticulously processed as any error or shift in parameters may change their physicochemical

Thus, it is fundamentally important to extract them with minimal change into its original structure [32]. The physical process of removing the ores or materials from the ground is disruptive to the environment and alarming questions regarding the statutory norms for safety are overwhelming. Also, the pre and post process for concentration of raw material and final product is time consuming and makes an essential call for the higher degree of purification. This leads to the generation of many undesirable chemical steps, adding to cost of actual extraction process as well

To solve this complicated situation, we bring the concept of Unearthed Humus, DCP – clean, economical, and essentially inert to any climatic condition, due to its generation in to the biotic environment of cow's rumen. It is with least contaminants as the process of Humification takes place during the period of 1 month of Sun drying, hence conditioning of any type is not required thanks to its biological matrix. These qualities of DCP projects the Zero Waste concept of Waste Management, boosting Green Chemistry principles. Zero Waste Management is the holistic concept of waste management which recognizes waste as a resource produced during the interim phase of the process of resource consumption [33]. The prime objective of this protocol is based on the sustainable avoidance and management of waste and

gases, that together support life. It comprises of weathered rocks from the lithosphere, trapped air pockets from the atmosphere, moisture from the hydrosphere, along with decomposing matter from the biosphere, and is thus known as an interface between these subsystems. Besides purifying water in terrestrial systems, soils process decaying matter from the biosphere and recycle nutrients back into the food chain. The pedosphere thus interconnects with other spheres and regulates life

**26**

to standard desorption and re-adsorption cycles and finally the spent DCP can be employed as a landfill material in deteriorated soils. Because of its strong chelating properties, any residual metallic ions are well-bonded to DCP and do not leach out under normal environmental conditions.

This study concludes that DCP is affordable and adaptable due to its Combo nature and its acceptability lies in its working mechanism based on HSAB concept of sorption [45]. DCP has a great potential in the field of water decontamination, industrial water treatment and in abatement of water pollution.

### **3. Dry cowdung powder - DCP: The best of waste**

DCP is naturally available bioorganic, complex, polymorphic humified fecal matter of cow and is enriched with minerals, carbohydrates, fats, proteins, bile pigments, aliphatic - aromatic species such as HA, FA, Ulmic acid and Humus etc. Many functional groups such as carboxyl, phenols, quinols, amide, enhance its biosorption properties.

The total characterization of DCP has been carried out for its physical, chemical as well as microbiological properties. DCP was provided by Keshav Shrushti, Research Centre on Cow products (Thane, India). Fresh cow dung was collected by efficient workers and due safety measures were taken to avoid any toxic and heavy metal contamination during collection. Cow dung is basically the feed residues digested by symbiotic bacteria residing within the animal rumen. The net effect of digestion in the rumen is the conversion of dietary materials to a mixture of fatty acids (mainly acetic, butyric and propionic acids), gases (primarily CO2 and CH4 which are voided by eructation) and microbial biomass [46]. The innate existence of different microbes, beetles and other dung related arthropods bring about humification of the organic matter present in cow dung [47].

There are different pigments and lipids in cow dung which are related to its color and typical odor. The bile pigment biliverdin is mainly present in cow dung (herbivore) giving it its green color. Also, bile salts give dung its emulsifying properties by which it confers hydrophilic coat to the droplets, otherwise of its hydrophobic nature [48]. It is also flourished with number of microorganisms as well as some classes of Arthropods. To ascertain passive biosorption by dead microbes, it is necessary to have an overall account of microbiological consortium of fresh dung.

Cow dung consists of approximately 60 species of bacteria, including species from the following genera - Bacillus, Actinomycetes, Corynebacterium, Pseudomonas, Cellulomonas, Flavobacterium, Lactobacillus, Serratia, and Alcaligens [49, 50]. It also includes *Escherichia coli* and Staphyloccocus aureus along with roughly 100 species of protozoa and yeasts including Saccharomyces and Candida spp. Cow dung also contains certain fungi like Trichoderma and Aspergillus spp. Due to the profusion of diverse micro flora, it has considerable potential for biodegradation and biotransformation [51].

The presence of petroleum utilizing microbes is indicative of high percentage of Hydrocarbon in the environment and cow dung too has a great abundance of this microbiota [52]. The presence of these microbes is also dependent on the geographical and environmental milieu. This microbial consortium enables cow dung with considerable potentials for biodegradation and biotransformation of oil - petroleum products and other pollutants as well as it further contributes to plant production and in many biogeochemical processes [53].

In order to select any new material for a process, the material should fulfill the theory of 3A's, which stand for affordability, acceptability, and adaptability. DCP is affordable due to its free availability and its supply is not hampered by climatic

**29**

**Table 1.**

**Sr. No.**

*Dry Cowdung Powder - Novel Unearthed Humus: Sustains Water-Food-Energy Nexus*

present global application emboss that DCP is the ultimate *Best of Waste*.

**4. Physical and chemical characterization of DCP**

contents has been carried out by Radial Chromatography.

been obtained, **Table 3** shows the same.

4. Solubility Sparingly soluble in water

**Physio-chemical parameters**

7. Potash content (kg/ ha)

8. Total Carbohydrate content

*Proximate analysis of DCP.*

*4.1.2 The elemental composition by XRF and CHNSO Analyzer*

conditions. Most of every HS available requires pretreatments or conditioning for optimal results, unlike DCP, hence it is more time, energy and cost efficient and hence has an edge over other HS. DCP is acceptable owing to its biological matrix, full of microbe's nutrients and least contaminated by any pollutant or contaminants, thanks to its production in perfectly inert or biological niche of rumen. Its adaptability is learned by its combo nature and heterogeneous functionality due to presence of numerous organic and inorganic ligands. These descriptions with its

The total characterizations of DCP for its physical and chemical properties have been designed. The physical characterization has been carried out by proximate analysis **Table 1** as per the standard procedure given by American Public Health Association (APHA). The elemental, structural, morphological analysis, and thermal stability of DCP has been conducted at Sophisticated Analytical Instrument Facility- Indian Institute of Technology (SAIF- IIT), Mumbai. Physical parameters such as moisture content, ash content, mesh size, fiber content, etc. have been evaluated. Biochemical analysis of DCP for its amino acid, carbohydrate and other

The DCP has been characterized using XRF technology for its quantitative as well as qualitative elemental composition as shown in **Table 2.** For the complete elemental composition, complimentary to XRF technique, C, H, N, S, (O), has also

**Value Sr.** 

1. Color and Odor Brownish, Humus smell 9. Crude fiber content 13.25%

3. Mesh size 100 11. Thermal stability Stable till

5. Moisture content 10–11% & 8.93% 13. pH 7.14

2. Texture/ Appearance Powdered 10. Total Nitrogen

except soluble sugars

6. Ash content 25.07% 14. Conductance

**No.**

**Physio-chemical parameters**

content

resistance

(mmhos/cm)

(kg/ha)

12. Acid-Alkali

525.00 15. % Organic carbon 0.60

37.13% 16. Humus content

**Value**

7.10%

150°C

Quite high

2.92

35.84

*DOI: http://dx.doi.org/10.5772/intechopen.98476*

**4.1 Physical characterization**

*4.1.1 Proximate analysis*

*Dry Cowdung Powder - Novel Unearthed Humus: Sustains Water-Food-Energy Nexus DOI: http://dx.doi.org/10.5772/intechopen.98476*

conditions. Most of every HS available requires pretreatments or conditioning for optimal results, unlike DCP, hence it is more time, energy and cost efficient and hence has an edge over other HS. DCP is acceptable owing to its biological matrix, full of microbe's nutrients and least contaminated by any pollutant or contaminants, thanks to its production in perfectly inert or biological niche of rumen. Its adaptability is learned by its combo nature and heterogeneous functionality due to presence of numerous organic and inorganic ligands. These descriptions with its present global application emboss that DCP is the ultimate *Best of Waste*.
