Description:FIELD OF THE INVENTION
The present invention in general relates to the management and biodegradation of solid waste. Particularly, the present invention relates to a system and apparatus for management and degradation of human waste. More particularly, the present invention relates to a biodigester for management and biodegradation of human waste in high altitude regions.

BACKGROUND OF THE INVENTION
Ensuring proper sanitation is crucial for maintaining public health, as inadequate waste disposal is a major source of pathogenic contamination, affecting soil, water, and air. With the global increase in population and rapid urbanization, existing waste management infrastructure is under immense strain, demanding the development of more efficient, sustainable systems for human waste treatment. Anaerobic digestion, or methanization, is a biological process that decomposes organic material, including human waste, under anaerobic (oxygen-deprived) conditions. This process generates biogas, predominantly methane, which can be harnessed as a renewable energy source. Additionally, it produces biosolids (sludge) and grey water, which can be repurposed as fertilizers. Biodigesters are engineered systems designed to optimize this anaerobic digestion process. These systems can be deployed at varying scales, converting human waste into valuable resources such as biogas for energy and grey water for agricultural use.
Several biodigester technologies exist in the prior art, each addressing different aspects of waste treatment:
1595/DEL/2006 describes an anaerobic digester designed for public transportation systems. The digester uses a dual-stage process combining biological and chemical treatment to degrade human waste.
WO2012042526A1 describes a self-sustaining biodigester designed for onboard applications, which integrates anaerobic biodegradation with chemical treatment, ensuring safe disposal of human waste in various environments.
2375/DEL/2010 describes a modular, stainless-steel biodigester intended for use in public transport vehicles. The system is divided into six chambers, each separated by partitions, and features a biological treatment component, a chlorinator for chemical treatment, and a non-biodegradable waste elimination mechanism. The system facilitates microbial activity through immobilization matrices and disinfects waste prior to disposal.
US13876791A1 describes a public transportation sanitation system by employing anaerobic digestion to minimize environmental impact. The document describes that the system is particularly effective at preventing non-biodegradable materials from entering the system, enhancing the ecological sustainability of waste treatment processes.
US7560026B2 describes a two-stage anaerobic digester, combining mesophilic and thermophilic digestion stages. The system optimizes waste decomposition through precise temperature control, mild agitation, and heat recovery mechanisms.
Although several systems are available and offer significant advancements, however they are predominantly designed for tropical climates, operating effectively in temperature ranges between 20°C and 50°C. Further, the available systems focus on biogas generation and fertilizer production under mesophilic and thermophilic conditions. However, they are ill-suited for high-altitude or extremely cold environments, where ambient temperatures can drop below -30°C, often reaching -40°C. In such conditions, conventional biodigesters face operational challenges, including freezing of components, pipe blockages, and severe limitations in microbial activity, making effective sanitation nearly impossible. Given these limitations, human waste disposal in remote, high-altitude, and low-temperature regions remains a pressing issue. The slow rate of natural biodegradation in such environments exacerbates the problem, leading to unsanitary conditions and heightened health risks.
To address these challenges, there is an urgent need for an advanced biodigester capable of functioning in extreme low-temperature environments. The present invention responds to this need by offering an eco-friendly, cost-effective, and portable solution that can operate in high-altitude, sub-zero regions with minimal water consumption. Designed to be lightweight, efficient, and resilient, this biodigester represents a breakthrough in sustainable sanitation technology, ensuring reliable waste treatment even in the harshest environmental conditions.
SUMMARY OF THE INVENTION
This summary is provided to introduce a selection of concepts in a simplified format that are further described in the detailed description of the invention.

In an aspect of the present invention, there is provided a portable biodigester (100) for degradation of human waste, the biodigester comprising:
a primary compartment (101) and a secondary compartment (102) connected by a connecting bend pipe (111);
wherein the primary compartment (101) comprises plurality of chambers separated by perforated walls (117) for flow of digested waste; and wherein the primary compartment is provided with a commode (104) on top;
wherein the secondary compartment (102) comprises two chambers separated by a non-perforated wall (113), atleast one biogas release valve (106) for controlled venting of biogas; and
wherein the biodigester (100) is suitable for degradation of human waste at a temperature in a range of -30°C to -40°C.

In an embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, the biodigester, wherein primary compartment (101) and secondary compartment (102) comprises a combination of external and internal layers of insulation.

In another embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the external layer comprises a layer of fiber-reinforced plastic (FRP) having a thickness of 1-2mm; and a layer of polyurethane foam (PUF) having a thickness of 56-58mm; and an internal layer of insulation comprises a layer of polyethylene grass mat (112) provided on the wall and at the bottom of the biodigester (100).

In yet another embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the primary compartment (101) and the secondary compartment (102) are 1000 mm in length, 1000 mm in width, and 700 mm in height, and wherein the primary compartment (101) and secondary compartment (102) comprises a nut welded stainless steel ring (108) with a silicon gasket (119) with an insulated air-tight lid (103) fixed by multiple bolts.

In still another embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the connecting bend pipe (111) is for passage of excess water or overflow water from the primary compartment (101) to the secondary compartment (102).

In yet another embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the primary compartment (101) and secondary compartment (102) comprises atleast one drain valve (105) for removing sludge.

In still another embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the commode (104) is a stainless-steel commode; and wherein the commode is an Indian or a western-style commode.

In an embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the commode (104) directs the waste to the primary compartment (101); and wherein the primary compartment (101) comprises blend of microbes for degradation of human waste.

In another embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the blend of microbes comprises anaerobic, aerobic and cold loving bacteria at a temperature ranging from 5oC- 55oC; and wherein the microbes degrade the waste.

In still another embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the secondary compartment (102) is provided with an overflow water pipe (114) for flow of fully digested wastewater.

In yet another embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the secondary compartment (102) is provided with forced drainpipe (115) for draining out the completely digested grey water; and wherein the secondary compartment (102) is further provided with a submersible pump (120) through an inverted U pipe.

In an embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the forced drainpipe (115) is insulated with a thermal insulation cap (121) and is covered with an insulated dome (107) to prevent freezing.

In another embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the biodigester (100) is provided with plurality of heating source maintaining an internal temperature in the range of 15-18°C; and wherein the plurality of heating source comprises primary heating source and secondary heating source.

In still another embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the primary heating source is circulating hot water generated during flushing process in the commode (104), and the secondary heating source comprises heating elements integrated within the walls (116) of the biodigester (100).

In an embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the biodigester (100) optionally comprises a tertiary heating element (110) provided in the primary compartment (102) having a capacity of 25 W each.

These and other features, aspects, and advantages of the present disclosure will become better understood with reference to the following description and appended claims. This summary is provided to introduce a selection of concepts in a simplified form. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
These and other features, aspects, and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
Figure 1 illustrates the schematic external view of the biodigester.
Figure 2 illustrates the schematic view of the internal components of the biodigester.
Figure 3 illustrates the schematic view of the anti-freeze arrangement.

DETAILED DESCRIPTION OF THE INVENTION
Those skilled in the art will be aware that the present disclosure is subject to variations and modifications other than those specifically described. It is to be understood that the present disclosure includes all such variations and modifications. The disclosure also includes all such steps of the process, features of the disclosure, referred to or indicated in this specification, individually or collectively, and any and all combinations of any or more of such steps or features.

Definitions: For convenience, before further description of the present disclosure, certain terms employed in the specification, and examples are collected here. These definitions should be read in the light of the remainder of the disclosure and understood by a person skilled in the art. The terms used herein have the meanings recognized and known to those of skill in the art, however, for convenience and completeness, particular terms and their meanings are set forth below.
The articles “a”, “an” and “the” are used to refer to one or more than one (i.e., to at least one) of the grammatical object of the article. The terms “comprise” and “comprising” are used in the inclusive, open sense, meaning that additional elements may be included. It is not intended to be construed as “consists of only”. Throughout this specification, unless the context requires otherwise the word “comprise”, and variations such as “comprises” and “comprising”, will be understood to imply the inclusion of a stated element or step or group of elements or steps but not the exclusion of any other element or step or group of elements or steps.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the disclosure, the preferred methods and materials are now described.

The present invention provides a biodigester (100) specifically engineered for deployment in high-altitude regions and environments subject to extreme cold, maintaining operational functionality at temperatures as low as -40°C. The biodigester (100) developed in the present invention is designed to function in odourless manner. The biodigester (100) described herein in the specification features a dual-compartment design consisting of a primary digester compartment (102) and a secondary digester compartment (103). Both compartments are constructed primarily from Fiber-Reinforced Plastic (FRP), chosen for its high compressive strength and resistance to environmental degradation. The FRP is combined with Polyurethane Foam (PUF) to form a composite material with superior thermal insulation properties, essential for maintaining the internal temperature required for efficient digestion. The structural integrity of the compartment is further enhanced by the use of a 2mm thick internal FRP layer, which provides mechanical strength, while the external PUF layer, measuring 58mm in thickness, offers insulation and great mechanical strength to the digester chamber. The internal walls of the compartments are lined with a Polyethylene Grass Mat (110), which serves as a substrate for the blended bacteria, preventing washout and ensuring continuous microbial activity. The overall dimensions of each compartment are 1000 mm in length, 1000 mm in width, and 700 mm in height. The compartments are installed subterraneously, providing additional thermal stability and protection from severe environmental factors. The biodigester (100) is designed for subterranean installation, leveraging geothermal insulation to further enhance thermal stability and protect the system from external environmental fluctuations. Waste input is managed through a sanitary commode (104) connected via a PVC pipe, ensuring efficient transfer of human waste into the primary compartment with minimal odor emission. The biodigester (100) developed in the present invention offers a robust, efficient, and sustainable solution for the digestion of human waste in extreme environmental conditions. Its high insulation capability, integrated temperature regulation, optimized effluent management, and streamlined design collectively contribute to its superior performance and adaptability, makes it an innovative advancement in the field of environmental engineering and waste management.
Thus, with accordance with the present invention, there is provided a portable biodigester (100) for degradation of human waste, the biodigester comprising:
a primary compartment (101) and a secondary compartment (102) connected by a connecting bend pipe (111);
wherein the primary compartment (101) comprises plurality of chambers separated by perforated walls (117) for flow of digested waste; and wherein the primary compartment is provided with a commode (104) on top;
wherein the secondary compartment (102) comprises two chambers separated by a non-perforated wall (113), atleast one biogas release valve (106) for controlled venting of biogas; and
wherein the biodigester (100) is suitable for degradation of human waste at a temperature in a range of -30°C to -40°C.

The biodigester (100) is constructed using a combination of high-performance insulation materials, including Fiber-Reinforced Plastic (FRP) and Polyurethane Foam (PUF). These materials enable the storage of thermal energy for longer period ensuring sustainable operation even in sub-zero conditions down to -40°C. The advanced insulation capacity is pivotal for maintaining the internal environment required for efficient microbial activity. The internal surfaces are lined with a polyethylene grass mat (110), which supports the adherence and proliferation of blended bacterial consortia, thereby preventing bacterial washout and ensuring sustained digestion processes.

In an embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein primary compartment (101) and secondary compartment (102) comprises a combination of external and internal layers of insulation.

In another embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the external layer comprises a layer of fiber-reinforced plastic (FRP) having a thickness of 1-2mm; and a layer of polyurethane foam (PUF) having a thickness of 56-58mm; and an internal layer of insulation comprises a layer of polyethylene grass mat (112) provided on the wall and at the bottom of the biodigester (100).

In yet another embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the primary compartment (101) and the secondary compartment (102) are 1000 mm in length, 1000 mm in width, and 700 mm in height, and wherein the primary compartment (101) and secondary compartment (102) comprises a nut welded stainless steel ring (108) with a silicon gasket (119) with an insulated air-tight lid (103) fixed by multiple bolts.
The biodigester employs a commercially available blend of microbial bacteria, specifically selected and acclimated for this application. The digestion process is carried out in four sequential stages:
Hydrolysis: In this initial phase, hydrolytic bacteria break down complex organic polymers into simpler monomers, such as sugars, which can then be processed by other bacteria.
Acidogenesis: This phase involves the conversion of these monomers into volatile fatty acids, hydrogen, and carbon dioxide by acidogenic bacteria.
Acetogenesis: During this stage, acetogenic bacteria convert the volatile fatty acids into acetic acid, along with additional hydrogen and carbon dioxide.
Methanogenesis: The final stage involves methanogenic bacteria converting acetic acid and hydrogen into methane and carbon dioxide, resulting in the production of biogas.
The biogas generated is primarily composed of methane and carbon dioxide, while the residual solid material (sludge) and liquid (grey water) remain mineral-rich. These byproducts can be repurposed as fertilizer following appropriate post-treatment processes.
In an embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the connecting bend pipe (111) is for passage of excess water or overflow water from the primary compartment (101) to the secondary compartment (102).
In another embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the primary compartment (101) and secondary compartment (102) comprises atleast one drain valve (105) for removing sludge.
In yet another embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the commode (104) is a stainless-steel commode; and wherein the commode is an Indian or a western-style commode.
In still another embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the commode (104) directs the waste to the primary compartment (101); and wherein the primary compartment (101) comprises blend of microbes for degradation of human waste.
In an embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the blend of microbes comprises anaerobic, aerobic and cold loving bacteria at a temperature ranging from 5oC- 55oC; and wherein the microbes degrade the waste.
In another embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the secondary compartment (102) is provided with an overflow water pipe (114) for flow of fully digested wastewater.
In yet another embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the secondary compartment (102) is provided with forced drainpipe (115) for draining out the completely digested grey water; and wherein the secondary compartment (102) is further provided with a submersible pump (120) through an inverted U pipe.
In still another embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the forced drainpipe (115) is insulated with a thermal insulation cap (121) and is covered with an insulated dome (107) to prevent freezing.
Given the biodigester’s operation in extreme temperatures, a robust thermal management system is essential. The system maintains its internal temperature through a combination of passive and active heating methods. The biodigester is engineered with a MSH system to ensure optimal microbial growth for efficient digestion. The primary heating is achieved through hot water supplied during flushing via the commode (104), providing periodic and direct thermal regulation to maintain the necessary internal temperature. This foundational heating system ensures the digester operates efficiently under normal conditions.
The biodigester includes a secondary heating source, comprising heating elements integrated into the digester walls, which supplements the primary heating system to ensure precise thermal management. In extreme ambient conditions, an optional tertiary heating element is available as a backup, ensuring continuous operation when additional heat is necessary. The microbial blend is capable of functioning efficiently within a temperature range of 5°C to 55°C. To maintain optimal digestion, the multi-stage heating (MSH) system is engineered to sustain an internal temperature between 15°C and 18°C. Even under harsh environmental conditions, with external temperatures dropping as low as -30°C to -40°C, the total heat input required remains under 100 W, ensuring efficient energy use.
In yet another embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the biodigester (100) is provided with plurality of heating source maintaining an internal temperature in the range of 15-18°C; and wherein the plurality of heating source comprises primary heating source and secondary heating source.
In an embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the primary heating source is circulating hot water generated during flushing process in the commode (104), and the secondary heating source comprises heating elements integrated within the walls (116) of the biodigester (100).
In another embodiment of the present invention, there is provided a portable biodigester (100) for degradation of human waste, wherein the biodigester (100) optionally comprises a tertiary heating element (110) provided in the primary compartment (102) having a capacity of 25 W each.
Advantages of biodigester:
a) The biodigester developed in the present invention comprises high-quality insulation which helps in maintaining heat for longer periods, enabling efficient operation even at extremely low temperature.
b) The biodigester developed in the present invention is lightweight and have disassemblable components, weighing less than 60 kg for enhanced portability.
c) The biodigester is specifically designed to function efficiently at temperatures as low as -40°C, making it suitable for high-altitude and cold environments where traditional biodigesters fail due to freezing and inhibited microbial activity.
d) The biodigester's lightweight, modular structure allows for easy transportation and installation, even in remote locations. It supports both Indian and Western-style commodes, offering flexibility in use.
e) The biodigester of the present invention incorporates advanced insulation materials like Fiber-Reinforced Plastic (FRP) and Polyurethane Foam (PUF), which reduce heat loss and help maintain optimal internal temperatures for microbial digestion.
f) The biodigester uses a blend of anaerobic, facultative, and cold-loving bacteria to rapidly digest human waste, minimizing foul odors and the growth of harmful pathogens.
g) It is designed to operate without rotating elements and with minimal heat input (less than 100 W), resulting in reduced energy consumption compared to conventional systems.
h) The use of a grass mat matrix provides an ideal surface for microbial growth, accelerating the digestion process and preventing harmful bacteria from proliferating.
i) The biodigester can utilize various heating methods, including heating through wall, hot water flushing, and stand by electrical heating elements. This versatility ensures reliable operation powered by renewable energy, eliminating the need for complex external heating systems.
j) The MSH mechanism ensures optimal digestion in extreme conditions with under 100 W of energy, through hot water flushing (primary), through wall-integrated heating (secondary), and a back and a backup system (tertiary) for continuous, efficient operation.
EXAMPLES
The present invention illustrated, with the help of the following example, which is not intended to limit the scope of the invention and any such modification therein falls within the scope of this invention. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are intended to provide further explanation of the subject matter.

Example 1: Working of Portable Biodigester
The portable shelter developed in the present invention is experimentally tested in the real field. The average value of the different test parameters is shown in the Table 1. The tested values of treated greywater align well with standard parameters, making it suitable for agricultural use or safe disposal without harming the environment. Further, the design assures that the bio digester functions in an odorless manner and uses less water. The structure of biodigester weighs much within the 50-60kg threshold, thus making it easily relocatable.
Table 1: The Average Test Parameters:
Sl. No Test parameter Units Grey water
1 TDS mg/l 1166
2 pH -- 7
3 COD mg/l 288
4 BOD mg/l 115
5 TURBUDITY NTU 137
6 DO mg/l 5.7

, Claims:We Claim:

1. A portable biodigester (100) for degradation of human waste, the biodigester comprising:
a primary compartment (101) and a secondary compartment (102) connected by a connecting bend pipe (111);
wherein the primary compartment (101) comprises plurality of chambers separated by perforated walls (117) for flow of digested waste; and wherein the primary compartment is provided with a commode (104) on top;
wherein the secondary compartment (102) comprises two chambers separated by a non-perforated wall (113), atleast one biogas release valve (106) for controlled venting of biogas; and
wherein the biodigester (100) is suitable for degradation of human waste at a temperature in a range of -30°C to -40°C.

2. The biodigester (100) as claimed in claim 1, wherein primary compartment (101) and secondary compartment (102) comprises a combination of external and internal layers of insulation.

3. The biodigester (100) as claimed in claim 2, wherein the external layer comprises a layer of fiber-reinforced plastic (FRP) having a thickness of 1-2mm; and a layer of polyurethane foam (PUF) having a thickness of 56-58mm; and an internal layer of insulation comprises a layer of polyethylene grass mat (112) provided on the wall and at the bottom of the biodigester (100).

4. The biodigester (100) as claimed in claims 1-3, wherein the primary compartment (101) and the secondary compartment (102) are 1000 mm in length, 1000 mm in width, and 700 mm in height, and wherein the primary compartment (101) and secondary compartment (102) comprises a nut welded stainless steel ring (108) with a silicon gasket (119) with an insulated air-tight lid (103) fixed by multiple bolts.

5. The biodigester (100) as claimed in claim 1, wherein the connecting bend pipe (111) is for passage of excess water or overflow water from the primary compartment (101) to the secondary compartment (102).

6. The biodigester (100) as claimed in claims 1-5, wherein the primary compartment (101) and secondary compartment (102) comprises atleast one drain valve (105) for removing sludge.

7. The biodigester (100) as claimed in claims 1-6, wherein the commode (104) is a stainless-steel commode; and wherein the commode is an Indian or a western-style commode.

8. The biodigester (100) as claimed in claims 1-7, wherein the commode (104) directs the waste to the primary compartment (101); and wherein the primary compartment (101) comprises blend of microbes for degradation of human waste.

9. The biodigester (100) as claimed in claims 1-8, wherein the blend of microbes comprises anaerobic, aerobic and cold loving bacteria at a temperature ranging from 5oC- 55oC; and wherein the microbes degrade the waste.

10. The biodigester (100) as claimed in claims 1-9, wherein the secondary compartment (102) is provided with an overflow water pipe (114) for flow of fully digested wastewater.

11. The biodigester (100) as claimed in claims 1-10, wherein the secondary compartment (102) is provided with forced drainpipe (115) for draining out the completely digested grey water; and wherein the secondary compartment (102) is further provided with a submersible pump (120) through an inverted U pipe.

12. The biodigester (100) as claimed in claim 11, wherein the forced drainpipe (115) is insulated with a thermal insulation cap (121) and is covered with an insulated dome (107) to prevent freezing.

13. The biodigester (100) as claimed in claims 1-12, wherein the biodigester (100) is provided with plurality of heating source maintaining an internal temperature in the range of 15-18°C; and wherein the plurality of heating source comprises primary heating source and secondary heating source.

14. The biodigester (100) as claimed in claim 1-13, wherein the primary heating source is circulating hot water generated during flushing process in the commode (104), and the secondary heating source comprises heating elements integrated within the walls (116) of the biodigester (100).

15. The biodigester (100) as claimed in claims 1-14, wherein the biodigester (100) optionally comprises a tertiary heating element (110) provided in the primary compartment (102) having a capacity of 25 W each.