FIELD OF INVENTION
The present invention relates to the broad field of bioremediation. More specifically the
invention relates to an eco-friendly method and an apparatus for carrying out the same, in
which ligninous and other difficult-to-biodegrade waste such as coconut shell, thermocol
pieces, lantana, ipomoea, etc are treated by harnessing the special ability of termites to breakdown
and assimilate this kind of waste.
BACKGROUND OF THE INVENTION
Biowaste such as animal manure, vegetable and fruit discards, municipal and industrial
sludge, etc, can be biodegraded by composting, vermicomposting, or anaerobic digestion -
singly or in combination - to utilizable products. Waste paper can either be recycled to make
wrappers, paper boards, etc, or can be composted/vermicomposted after mixing it with
animal manure. But ligninous or ‘hard’ biowaste such as coconut shells, thermocol pieces,
twigs and branches of invasives like ipomoea or lantana, etc, resist composting,
vermicomposting, or anaerobic digestion. Nor are there any other options available to utilize
them or dispose them in a cost-effective and eco-friendly manner. Such waste continues to
pose an increasingly daunting challenge which has not been surmounted despite concerted
efforts. The amphibious weed Ipomoea (Ipomoea carnea) is one of the most productive of
macrophytes, growing profusely in water bodies and on adjoining marshy lands, often
jostling out most other plant species. It is known to exert allopathic effect on some plants and
has been shown to possess mammalian toxicity. Despite enormous efforts to destroy or
control this weed, it continues to thrive. Attempts to utilize it have met with more or less
equally feeble success. Such attempts have compassed a gamut: possible use as livestock
feed, building material, paper pulp, source of drugs, fuel etc. – but only very small quantities
of the weed is utilizable in one or the other manner. Even such utilization options are regionspecific
and serve a limited purpose in situations when better options are not available.
Even as huge quantities of ipomoea are generated when ipomoea dies or is mechanically
detached from land/water to reduce its infestation, in absence of any means of gainfully
disposing it, it is left to rot, generating methane and carbon dioxide which are both global
warming gases (GHGs). Of the two, methane is generated whenever anaerobic conditions
develop in the heaps of weed masses, which is quite often. As methane has 25 times greater
global warming potential than CO2, the consequences of the rotting of the weed in nature are
quite grave.
Hence a method which can handle such waste in an expensive and non-polluting manner is
the need of the hour.
As for termites, enormous research has been done, and is continued to be done, on their
biology, ecology, and eradication - the compendia of Lee and Wood (1971), Bose (1984),
Pearce (1998), Abe et al (2000), Hadlington and Stanton (2006), Konig and Verma (2006),
etc, are only illustrative examples of scores of books and other forms of reviews available in
the field. But there are very few studies on the culture and the utilization of termites and none
whatsoever on the use of termites per se in pollution control/waste management.
Moreover, as on date, vermicomposting is the only bioprocess in existence which utilizes a
multicellular animal as the main bioagent. Hence the need for a method such as the proposed
one which, promises to open new vistas, as it shows the potential of one or more family of
small-bodied animals for controlled processing of solid waste.
At present incineration is the only method available globally which can handle these types of
waste because biological methods such as composting, vermicomposting and anaerobic
digestion, which are capable of stabilizing non-ligninous biowaste in a cost-effective manner,
are incapable of treating waste of this kind. However, incineration leads to gaseous pollutants
which are difficult and expensive to treat and also generates difficult-to-dispose ash.
Accordingly, the present invention provides a novel method for eco-friendly treatment of
ligninous biowaste by harnessing naturally occurring termites. The present invention
addresses problematic wastes which defy composting/ vermicomposting or biomethanation
and are ‘pollutants’ in the real sense since they are not utilizable in the state they occur in a
waste, and the absence of options of their gainful utilization is a source of pollution.
Termites (which are exceedingly useful animals without whom our soils will become barren
and sterile), are under serious threat because of ‘development’. Their habitats are
continuously being destroyed. Also anti-termite poisons are used by anyone and everyone
and there is no penalty for harming termites (as there is for other forms of animal life). In
comparison, the proposed work actually supports termites by providing them access to food.
As that ‘food’ is anthropogenic waste, this invention helps humans as well as termites by the
proposed process. It is a truly green ‘affirmative action’ process which makes humans and
termites work towards a common good.
The proposed invention is neither specific to, nor confined to, the termites of India. It is
independent even of the termite species that naturally occur in Puducherry. Also it makes
non-destructive use of termites. Hence no consumption of termites, or their transportation
even within India or from city to city, is involved. Nor do we disturb their habitat in any
manner.
The present work consists of development of engineered systems which harness naturally
occurring termites to process a variety of hard/ligninous waste, and non-compostable portions
of invasive plants.
The present work is totally different in concept as well as execution from the studies reported
earlier. Firstly, it utilizes termitaria of different species naturally existing in the open.
Secondly it does not depend on creating any bulky, cumbersome, labour-consuming and
expensive ‘hubs’ or ‘feeding stations’ necessary in the earlier methods. Thirdly it is not
confined to treatment of paper waste but, rather, addresses much more difficult wastes. The
proposed method relies on the use of inexpensive and non-hazardous trails and baits for
enticing and guiding termites towards the waste. Accordingly, the present invention puts forth
for the first time ever, a controllable, utilizable, and reproducible method with which termites
can be used non-destructively in waste treatment.
OBJECTS OF THE INVENTION
An object of the present invention is to provide a novel method for eco-friendly treatment of
ligninous biowaste.
Another object of the present invention is to provide a novel method for odour-free, nondestructive
treatment of ligninous biowaste.
Another object of the present invention is to harness naturally occurring biomaterials to
biodegrade ligninous and other hard-to-biodegrade biowaste.
Yet another object of the present invention is to harness naturally occurring termites to
biodegrade ligninous and other hard-to-biodegrade biowaste.
Yet another object of the present invention is to provide specifically designed termireactors to
harness naturally occurring termites to biodegrade ligninous and other hard-to-biodegrade
biowaste.
Yet another object of the present invention is to provide the termicast produced in
biodegradation of biowaste as a fertilizer.
SUMMARY OF THE INVENTION
The invention presents an absolutely novel method in which ligninous and other difficult-tobiodegrade
waste such as coconut shell, thermocol pieces, lantana, ipomoea, etc are treated
by harnessing the special ability of termites to break-down and assimilate this kind of waste.
The method involves use of already established termite species (to safeguard against infesting
any region with a possibly invasive species). It relies on drawing the termites towards the
waste (food) by using pheromone-based baits and trails which were hitherto being used for
killing the termites. These baits and trails have been developed by the inventors after trying
out a large number of substances. Based on the trials, inexpensive and non-toxic substances
have been identified which provide effective trails and serve as baits.
The method can be operated using a large number of different termite species that occur in
different regions and does not require bringing any new species in any region. Hence the
method utilizes only those termite species that are already established in a region and carries
no risk of introducing alien species which can become invasive.
In another aspect of the invention, a novel termireactor for harnessing the biodegradative
capability of termites is provided.
The proposed invention addresses problematic wastes which defy composting/
vermicomposting or biomethanation and are ‘pollutants’ in the real sense since they are not
utilizable in the state they occur in a waste, and the absence of options of their gainful
utilization is a source of pollution.
The invention puts forth for the first time ever, a controllable, utilizable, and reproducible
method with which termites can be used non-destructively in waste treatment.
BRIEF DESCRIPTION OF THE DRAWINGS AND TABLES:
The accompanying drawings and tables illustrate embodiments of the invention and, together
with the description, serve to explain the invention. These drawings are offered by way of
illustration and not by way of limitation.
Fig. 1 A depicts multi-module in-situ termireactor for subterranean termites; B: depicts an
individual module; C: depicts a module carry-case for porting; D: depicts an add-on harvester
assembly for harvesting the termites.
Fig. 2 depicts an in-situ termireactor for termite species that forage on or just below the
ground surface.
Fig. 3 depicts an in-situ multipurpose termireactor.
Fig. 4 depicts a termireactor orientation and operation for subterranean termites.
Fig. 5 A depicts trails attachable to all embodiments, B: Photograph of a termireactor with
trails attached to it.
Fig. 6: A, B: Ipomoea termireactors with termite tunnels made on the substrate, C: Ipomoea
termireactor showing termite tunnels, D: Close up of the substrate with the tunnels
Table 1: Extent of termigradation (%) of Ipomoea carnea (5 Kg) at 10-day intervals
Table 2: Extent of termigradation (%) of Ipomoea carnea (20 Kg) 15-day intervals, in the
reactors without trails and the reactors supported by trails
Table 3: Extent of termigradation (%) of Ipomoea carnea (50 Kg) 15-day intervals
Table 4: Extent of termigradation (%) of Ipomoea carnea (100 Kg) 15-day intervals
DETAILED DESCRIPTION OF THE INVENTION
The present invention is described with reference to the accompanying drawings and
embodiments; this description is not meant to be construed in a limiting sense. Various
alternate embodiments of the invention will become apparent to persons skilled in the art,
upon reference to the description of the invention. It is therefore contemplated that such
alternative embodiments form part of the present invention. It is understood that the
embodiments are provided for the purpose of illustrating the invention only, and are not
intended to limit the scope of the invention in any way.
It is to be noted that a person skilled in the art can be motivated from the present invention
and modify the various constructions of assembly, which are varying for different areas and
biowastes. However, such modification should be construed within the scope and spirit of the
invention.
Accordingly, the drawings depict only those specific details that are pertinent to
understanding the embodiments of the present invention so as not to obscure the disclosure
with details that will be readily apparent to those of ordinary skill in the art having benefit of
the description herein.
Unless defined otherwise, technical and scientific terms used herein have the same meaning
as commonly understood by one of ordinary skill in the art to which this invention belongs.
Some of the terms are defined briefly herebelow; the definitions should not be construed in a
limiting sense.
The term ‘Termigradation’ as used herein refers to the controlled use of termites in the
bioprocessing of solid waste.
The term ‘Termireactor’ as used herein refers to bioreactors which enable termigradation.
The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover a
non-exclusive inclusion, such that a system, device that comprises a list of components
does not include only those components but may include other components not expressly
listed or inherent to such setup or device. In other words, one or more elements in a system
or apparatus proceeded by “comprises… a” does not, without more constraints, preclude the
existence of other elements or additional elements in the system or apparatus.
The present disclosure presents an absolutely novel method in which ligninous and other
difficult-to-biodegrade waste such as coconut shell, thermocol pieces, lantana, ipomoea, etc.
are treated by harnessing the special ability of termites to break-down and assimilate this kind
of waste.
The method involves use of already established termite species (to safeguard against infesting
any region with a possibly invasive species). It relies on drawing the termites towards the
waste (food) by using pheromone based baits and trails conventionally used to kill termites.
As these trails are a food source in themselves, the scouts and early workers eat through them
to reach the termireactor. In the method much stronger pheromone marking is likely than if
the termites were simply following a chemical trail. These baits and trails have been
identified as suitable for the method of the present invention by the inventors after trying out
a large number of substances. Based on the trials, inexpensive and non-toxic substances have
been identified which provide effective trails and serve as baits to lead the termites towards
the waste which is food for them.
The waste is kept in ‘termireactors’ designed by the inventors. These are placed in a way to
enable termites to easily access the waste. By developing appropriate baits and trails, and
appropriate termireactors, the overall method of waste decomposition has been made faster
than even the conventional processes of composting or vermicomposting which are used to
degrade simpler waste (but which cannot be used for ligninous solids).
Accordingly, the present invention also provides a novel termireactor to perform the method
of termigradation.
Unlike composting, this method is odour-free. Nor does it require energy that are essential for
composting (For example, aeration, periodic turning).
Towards the end of the ‘termigradation’, termites can be harvested and used as food for
humans and/or livestock. They provide high-quality animal protein and are consumed by
several communities in South India and elsewhere. Moreover the termicast produced in the
method has fertilizer value.
Overall the present invention needs much lesser material and energy inputs than most
bioprocesses such as even the relatively inexpensive ones like composting, vermicomposting
or anaerobic digestion. Nor does it generate gaseous, liquid, or solid waste.
The embodiments of the termireactors have been designed, based on the nature of the
substrate to be processed and the termite species to be harnessed for carrying out the
‘termigradation’. The broad principle followed in these designs has been:
1. Optimizing the reactor geometry to enable near complete utilization of the substrate
2. Ease of access to the substrate for the termites
3. Ease of portability, charging, and installation of the termireactors
4. Ease of removal of termigraded product from the reactors
5. Provision of harvesting the termites still present in the substrate
In one embodiment, there is a system of trails comprising of pipes (made of PVC or metals)
which can be attached to all the three types of termireactors.
In one embodiment of the present invention there is provided a novel method for eco-friendly
biodegradation of ligninous and other difficult-to-biodegrade hard biowaste, said method
comprising the following steps:
attracting naturally occurring termites by using pheromone based baits and trails to an
in-situ termireactor specifically designed to harness said naturally occurring termites;
allowing the termites to biodegrade said ligninous and other difficult-to-biodegrade
hard biowaste in said termireactor;
harvesting the termites to remove the biodegraded biowaste.
In another embodiment of the present invention there is provided a novel method for ecofriendly
biodegradation of ligninous and other difficult-to-biodegrade hard biowaste, said
method comprising the following steps:
attracting naturally occurring termites by using pheromone based baits and trails to an
in-situ termireactor specifically designed to harness said naturally occurring termites;
allowing the termites to biodegrade said ligninous and other difficult-to-biodegrade
hard biowaste in said ternireactor;
wherein said termite species are selected from a) subterranean termites, b) termites which
forage on, or just below, the soil surface and c) both above-ground and subterranean termites.
Another embodiment of the present invention provides novel in-situ termireactors [Fig. 1, 2
and 3] for carrying out eco-friendly biodegradation of ligninous and other difficult-tobiodegrade
hard biowaste, said termireactors designed specifically based on the nature of the
biowaste and the type of termites used in the method.
Multi-module in-situ termireactor, suitable for harnessing subterranean termites: In
another embodiment is provided a multi-module in-situ termireactor which is suitable for
harnessing subterranean termites. Figure 1 shows the components of this embodiment. The
termireactor consists of several modules (Figure 1A); the number of modules to be used
would depend on the quantity of substrate to be processed. Each module (Figure 1 B) is made
up of galvanized iron wire mesh. A protective covering, equipped with a handle, serves as a
lid to the module. The lid is lifted to charge (feed) the module and then replaced back. All the
modules of the reactor are thus charged, and then ported to the site and installed in belowground
pits.
After the designated termigradation time (10 – 20 days), the modules are lifted out and placed
in the carry case (Figure 1 C). The carry case consists of sliding removable panels on the
larger surface area sides of the case and two fixed panels on the other two smaller surface
area sides. The purpose of the carry case is to transport the module – which is made of wire
mesh on its five sides - in a way so as to prevent termite migration out of the container.
Figure 1 D shows the harvester assembly, consisting of two components. The first one fits
into one of the larger surface area sides of the reactor module and carries a light source to
induce migration of termites into the dark collection. The other one fits on the other larger
surface area side of the reactor, and contains waste paper or used cardboard. Once fitted into
the harvester assembly, the two sliding panels of the carry case are removed and the light
source is turned on. This causes the termites present in the reactor module to move away
from the light source towards the darker zone, which is the cardboard substrate present on the
other side of the reactor module. The light source is left on till the animal migration is
complete. The removable panels are then repositioned in the carry case and the harvester
assembly is disengaged from the module. The termigraded product can then be harvested
from the reactor module by lifting the lid and emptying the reactor contents.
Thus in the above embodiment of the present invention there is provided a novel in-situ
termireactor [1] for carrying out eco-friendly biodegradation of ligninous and other difficultto-
biodegrade hard biowaste, wherein the termireactor comprises:
a) one or more modules [2]; each module made of galvanized iron wire mesh [ 3 ] and
a protective covering lid [ 4 ] equipped with a handle [ 5 ];
b) a carry case [ 6 ] to transport the module, said carry case comprising a first [ 7a ]
and a second [ 7b ] larger surface area side and a first [ 8a ] and a second [ 8b ]
smaller surface area side;
said termireactor specifically designed to harness naturally occurring subterranean termites to
biodegrade said biowaste.
In another embodiment of the present invention there is provided a novel in-situ termireactor
[1] for carrying out eco-friendly biodegradation of ligninous and other difficult-to-biodegrade
hard biowaste as described above, wherein each of said first [ 7a ] and second [ 7b ] larger
surface area side is fitted with a removable sliding panel [ 7c ] and each of said first [ 8a ] and
second [ 8b ] smaller surface area side is fitted with a fixed panel [ 8c ].
In another embodiment of the present invention there is provided a novel in-situ termireactor
[1] for carrying out eco-friendly biodegradation of ligninous and other difficult-to-biodegrade
hard biowaste, said termireactor further comprising a harvester assembly comprising:
a. a first component [ 9 ] that fits into one of the said first larger surface area sides [
7a ] of the termireactor module and carries a light source [11 ],
b. a second component [10 ] that fits into said second larger surface area side [ 7b ]
of the termireactor, and contains the biowaste substrate.
In another embodiment of the present invention there is provided a method for eco-friendly
biodegradation of ligninous and other difficult-to-biodegrade hard biowaste using an in-situ
termireactor [1] as described above, said method comprising the following steps:
a. charging the module [ 2 ] with the substrate to be processed and covering the same
with the lid [ 4 ] ,
b. porting thus charged modules of the reactor to the site of biodegradation in carry
case [ 6 ],
c. allowing the termites to act on the substrate to be processed,
d. installing the harvester assembly in below-ground pits with the charged modules
fitted in said harvester assembly,
e. removing the two sliding panels of the carry case and turning on the light source [
11 ] causing the termites present in the reactor module to move away from the
light source towards the component containing the biowaste substrate,
f. leaving the light source on till the termite migration is complete,
g. repositioning the removable panels in the carry case and disengaging the harvester
assembly from the module,
h. harvesting the biodegraded product from the reactor module by lifting the lid and
emptying the reactor contents.
In-situ termireactor for termites which forage on, or just below, the soil surface: In
another embodiment is provided an in-situ termireactor for termites which forage on, or just
below, the soil surface. The termireactor has been sized to maximize surface-area/volume
ratio within the limiting condition that adequate substrate depth should be maintained to
provide the requisite shading from sunlight as well as humidity (Figure 2). The reactor is
made of wire mesh on all side. Metal angles placed at strategic intervals provide the
scaffolding for wire mesh. Both the upper and lower faces of the termireactor serve as lids
and are fastened with the help of fasteners and can be unfastened and swung open at the
hinges to charge/empty the reactor. Two handles are provided for facilitating the transport of
the reactor.
Thus in the above embodiment of the present invention there is provided a novel in-situ
termireactor [ 12 ] for carrying out the method of the embodiment, wherein the termireactor
comprises of a module made of galvanized iron wire mesh [13] on all sides having metal
angles [ 14 ] to provide scaffolding for said wire mesh;
said termireactor specifically designed to harness naturally occurring termites which forage
on, or just below the soil surface to biodegrade said biowaste.
In another embodiment of the present invention there is provided a novel in-situ termireactor
[12 ] as described above, wherein said termireactor is sized to maximize surface-area/volume
ratio within the limiting condition that adequate substrate depth be maintained to provide the
requisite shading from sunlight as well as humidity.
In another embodiment of the present invention there is provided a novel in-situ termireactor
[12 ] as described above, wherein the upper [ 15 ] surface of the termireactor serves as a lid
and can be swung open at the hinges by unfastening the fasteners [ 17 ] and to charge/empty
the reactor.
In another embodiment of the present invention there is provided a novel in-situ termireactor
[12 ] as described above, wherein two handles [18] are provided for facilitating the transport
of the termireactor.
In another embodiment of the present invention there is provided a method for eco-friendly
biodegradation of ligninous and other difficult-to-biodegrade hard biowaste using an in-situ
termireactor [12] as described above.
In-situ general purpose termireactor (can be used for both above ground and
subterranean foragers):
In another embodiment is provided an in-situ general purpose termireactor that can be used
for both above ground and subterranean foragers. The in-situ general purpose termireactor
can be employed for all species of termites (Figure 3). It is a cylindrical vessel made of wire
mesh with lids on both sides. It has angles to support the mesh, and also has a latching
mechanism. The orientation of the cylinder is kept vertical, with its flat surface touching the
ground, when the termigradation is done using subterranean termites (Figure 3 A). When
used with above-ground foragers, the cylinder is kept side-ways (Figure 3 B). Figure 4
illustrates how the reactor when used with subterranean termites (vertical orientation) is
charged, installed and emptied.
The trails attachment: Each of the termireactor embodiments described above can be fitted
on all sides with ‘trails’. These are narrow pipes in which paper, saw dust, or similar material
is partially filled to attract scout termites. The scouts forage through the bait to create strong
pheromone trails which then attracts termites from all sides. Figure 5 illustrates this provision
made in the third embodiment of the termireactors described here; the provision can be
similarly made in the other two embodiments as well.
Thus in the above embodiment of the present invention there is provided a novel in-situ
termireactor [19] for carrying out eco-friendly biodegradation of ligninous and other difficultto-
biodegrade hard biowaste, wherein the termireactor is a cylindrical vessel made of
galvanized iron wire mesh [20 ] comprising a first flat surface [ 21 ] and a second flat surface
[ 22 ] parallel thereto having lids [ 23, 24 ] on both the first and second flat surfaces,
said termireactor designed to harness both above ground and subterranean naturally occurring
termites to biodegrade said biowaste.
In yet another embodiment of the present invention there is provided a method for ecofriendly
biodegradation of ligninous and other difficult-to-biodegrade hard biowaste using an
in-situ termireactor [19] as described above, wherein
a. when the termigradation is done using subterranean termites, the orientation of
the cylindrical vessel is kept vertical, with its flat surface touching the ground,.
b. when the termigradation is done using above-ground termites, the orientation
of the cylindrical vessel is kept side-ways.
In yet another embodiment of the present invention there is provided novel in-situ
termireactors [Fig. 1, 2 and 3] for carrying out eco-friendly biodegradation of ligninous and
other difficult-to-biodegrade hard biowaste, wherein the termireactor can optionally be fitted
on all sides with trails comprising of narrow pipes of about 1 inch diameter and 5 m length [
25 ] partially filled with termite palatable material selected from paper, saw dust, or similar
material to attract scout termites.
In yet another embodiment of the present invention there is provided novel in-situ
termireactors [Fig. 1, 2 and 3] for carrying out eco-friendly biodegradation of ligninous and
other difficult-to-biodegrade hard biowaste, wherein said biowaste substrate is selected from
the group comprising ligninous and other difficult-to-biodegrade waste as coconut shell,
thermocol pieces, lantana, ipomoea and cardboard.
In yet another embodiment of the present invention there is provided a biofertilizer
comprising the termicast produced by method of biodegradation of ligninous and other
difficult-to-biodegrade hard biowaste by harnessing naturally occurring termites using an insitu
termireactor as claimed in any of the preceding claims.
The present invention is the first method of its kind which enables ligninous and other hardto-
biodegrade biowaste to be processed by controlled termite action and without the use of
any other chemical or any potentially toxic or invasive organism. It is also a method requiring
much lesser energy and supervisory inputs than other bioprocesses which aim to biodegrade
lignin thus making it an economically viable technology.
EXAMPLE 1
The method of the present invention was conducted as a field trial wherein about 10 Kg of
biowaste (a collection of ipomoea, pistia, water hyacinth, lantana) was decomposed in just 15
days. Similar or larger quantities of other biowastes (a collection of coconut shell, discarded
paper cups) were decomposed in 30 – 45 days. Hence the rate of this method is by far much
faster than the earlier known methods. It is also much faster than composting and
vermicomposting.
EXAMPLE 2
In an endeavour to find possible ways of gainfully utilizing large quantities of ipomoea in an
ecologically compatible and inexpensive manner it was subjected to the process of
termigradation of the present invention.
Four sets of experiments were conducted with different quantities of ipomoea. All the
reactors were charged with its twigs and placed near active termite mounds in the wooded
parts of the Pondicherry University campus. The first set comprised of six reactors with 5 kg
feed.
In the second set of experiments, a total of twelve termireactors were operated. All were
charged with 20 kg ipomoea. The first six reactors were placed near active termite mounds in
the wooded parts of the Pondicherry University campus. To enhance the rate of substrate
degradation, by attracting more number of termites to the reactor than coming naturally to the
reactor, six of the termireactors were supported by trails of paper waste and saw dust. These
trails, 8 in number, were laid alternatively and equidistance from each other going radially
outward upto 5 metres from each termireactor in all directions (Figure 5).
In the third set of experiments the termireactors were loaded with 50 Kg of the substrate:
triplicates were used with and without trails. Lastly four termireactors scaled to 100 kg feed
were explored: two with trails and two without trails. The extent of substrate consumption by
termites was quantified once in every ten days in reactors with 5 kg feed and once in fifteen
days in all the other reactors. The reactors were observed daily and the species present each
time were identified.
Table 1: Extent of termigradation (%) of Ipomoea carnea (5 Kg) at 10-day intervals
Days
Reactor Termigradation
A B C D E F During each run Cumulative
0-10 21.8 23.6 20.1 18.4 18.1 18.8 20.1±2.2 20.1±2.2
11-20 14.3 15.0 20.3 17.9 17.5 18.4 17.2±2.2 37.4±1.8
21-30 15.5 15.5 17.3 16.1 15.5 16.6 16.1±0.7 53.5±2.4
31-40 13.2 13.3 11.0 8.5 8.4 8.5 10.5±2.4 63.9±3.7
41-50 8.9 8.4 8.5 8.7 8.8 8.6 8.7±0.2 72.6±3.5
51-60 6.9 6.4 4.0 5.9 6.1 6.0 5.9±1.0 78.5±3.3
61-70 3.7 3.4 4.2 3.7 3.9 3.7 3.8±0.3 82.2±3.3
71-80 3.8 3.2 2.0 3.3 3.4 3.3 3.2±0.6 85.4±3.1
81-90 1.7 1.5 1.6 2.8 3.0 7.4 3.0±2.2 88.4±2.7
91-100 1.2 1.1 1.0 1.5 1.5 0.9 1.2±0.3 89.6±2.5
Table 2: Extent of termigradation (%) of Ipomoea carnea (20 Kg) 15-day intervals, in the reactors without trails and the reactors
supported by trails
Days
Reactors without trails Termigradation Reactors supported by trails Termigradation Increase (I) or
decrease (D) in
termigradation
by use of trails,
significant to
confidence
level
A B C D E F
During
each run
Cumulative A B C D E F
During
each run
Cumulative
0-15 37.4 38.2 39.4 33.2 33.6 31.4 35.5±3.2 35.5±3.2 59.3 60.1 60.2 46.6 47.3 47.3 53.5±7.0 53.5±7.0 I 99.5
16-30 25.2 26.9 25.4 21.9 21.4 20.7 23.6±3.0 59.1±5.7 27.3 27.1 27.0 27.4 26.6 27.1 27.1±0.3 80.7±7.2 I 99
31-45 14.5 15.7 16.8 11.8 11.2 10.9 13.5±2.5 72.6±8.2 8.2 8.0 7.6 14.8 14.7 14.8 11.4±3.7 92.0±3.4 D 70
46-60 10.8 11.4 12.0 4.0 4.6 4.9 8.0±3.8 80.6±11.9 - - - 7.6 8.2 7.7 7.8±0.3 96.7±0.2 D 80
61-75 6.6 5.2 4.6 9.7 8.4 10.5 7.5±2.4 88.1±9.6 - - - - - - - -
76-90 2.9 1.8 1.2 8.1 7.7 6.4 4.7±3.0 92.8±9.6 - - - - - - - -
90-105 - - - 6.9 6.1 5.3 6.1±0.8 98.9±2.8 - - - - - - - -
Table 3: Extent of termigradation (%) of Ipomoea carnea (50 Kg) 15-day intervals
Days
Reactors without trails Reactors supported by trails Increase (I) or
decrease (D) in
termigradation
by use of trails,
significant to
confidence level
Reactor Termigradation Reactor Termigradation
A B C During
each run
Cumulative A B C During
each run
Cumulative
0-15 27.4 25.6 28.9 27.3±1.6 27.3±1.6 39.7 40.1 43.8 41.2±2.2 41.2±2.2 I 99.5
16-30 19.7 18.1 22.4 20.1±2.2 47.1±3.8 27.1 27.8 29.7 28.2±1.3 69.4±3.5 I 99.5
31-45 12.6 11.8 13.7 12.7±0.9 59.8±4.8 18.2 18.8 20.5 19.2±1.2 88.6±4.8 I 99.5
46-60 6.9 6.1 7.8 6.9±0.8 66.7±5.7 10.4 10.9 4.2 8.5±3.7 97.1±1.4 I 60
61-75 10.9 9.3 10.1 10.1±0.8 76.8±6.0 - - - - - -
76-90 9.1 7.9 7.1 8.0±1.0 84.8±5.6 - - - - - -
91-105 6.4 6.1 5.5 6.0±0.4 90.8±5.4 - - - - - -
106-120 3.6 4.8 2.9 3.8±0.9 94.6±4.4 - - - - - -
Table 4: Extent of termigradation (%) of Ipomoea carnea (100 Kg) 15-day intervals
Days
Reactorswithout trails Reactors supported bytrails Increase (I) or
decrease (D) in
termigradation by
use of trails,
significant to
confidence level
Reactor Termigradation Reactor Termigradation
A B
During
each run
Cumulative
C D
During
each run
Cumulative
0-15 29.7 28.9 29.3±0.6 29.3±0.6 42.7 45.4 44.1±1.4 44.1±1.4 I 95
16-30 20.1 19.6 19.9±0.4 49.2±0.9 26.5 28.6 27.6±1.5 71.6±3.3 I 90
31-45 14.2 13.5 13.9±0.5 63.0±1.4 19.8 20.9 20.4±0.8 92.0±4.1 I 95
46-60 10.1 9.3 9.7±0.6 72.7±2.0 6.7 3.2 5.0±2.5 96.9±1.7 D 90
61-75 9.2 8.5 8.9±0.5 81.6±2.5 - - - - -
76-90 7.5 6.8 7.2±0.5 88.7±3.0 - - - - -
91-105 6.1 5.5 5.8±0.4 94.5±3.4 - - - - -
All quantities are reported on ‘dry weight basis’; it is the equivalent of fresh weight of the
substrate oven dried at 105°C to constant weight.
The ‘termigradation’ ─ or the rate of consumption of the substrate by termites ─ is seen to be
the highest during the initial 10-15 days (Tables 1-4). By the 30th day about half of the feed
was termigraded in all reactors without trails and about 70% in reactors with trails.
In all the reactors supported with trails, > 90% of the feed was consumed within 60 days,
whereas the consumption was 80.6, 66.7 and 72.7% in the reactors with 20 kg, 50 kg and 100
kg of feed respectively which were not supported by trails. The enhancement in the
termigradation efficiency due to the trails was statistically significant (Tables 1-4) as revealed
by the Student’s t-test (Microsoft Excel, 2010). This happened till the bulk of the substrate
had been consumed in reactors with trails. Thereafter termite activity reduced sharply in these
reactors and less substrate was consumed than in the reactors without trails. Termites were
seen to feed upon ipomoea by constructing tunnels (Figure 6). After assimilation of the weed,
only a small residue of particulates was found in the reactors. Hypotermes obscuriceps was
the species present throughout but occasionally Macrotermes convulsionarius was observed.
Independent of the initial feed quantity and whether or not the reactors were supported with
trails, ~ 50% of the substrate was consumed within a month in all the reactors. This time-span
can be considered very short as compared to the conventional forms of composting or
vermicomposting of biodegradable waste which take much longer. More significantly,
whereas periodic supervision for maintaining moisture, turning of substrates (needed in
composting), and resultant energy/material inputs, that are necessary in those conventional
processes, the same are not required in termigradation. Hence this is a much less expensive
method with much lesser ‘footprint’.
This also demonstrates the applicability of the method of the present invention across a wide
range of scales, as reactors of capacity ranging from 5Kg to 100 Kg were successfully used.
ADVANTAGES OF PRESENT INVENTION:
1. By developing appropriate baits and trails, and appropriate termireactors, the overall
method of waste decomposition has been made faster than even the conventional
processes of composting or vermicomposting which are used to degrade simpler waste
(but which can’t be used for ligninous solids).
2. Hence the proposed method relies on the use of inexpensive and non-hazardous trails and
baits for enticing and guiding termites towards the waste.
3. Versatile method, capable of handling a wide variety of waste which (unlike paper) defies
composting and vermicomposting
4. Faster and more efficient: sizeable decomposition is achieved for several substrates in just
15 days and most others in 30 – 45 days.
5. Process control is possible by enhancing, reducing, or removing the baits and trails.
6. The feed is placed in well- ventilated reactors with access to ambient soil all around. This
creates an environment very similar to the one termites prefer, especially in terms of
dampness, humidity, proximity to soil, and protection from light.
6. Can be scaled up without any loss of process control or cost-effectiveness.
7. Further, unlike composting, this method is odour-free. Nor does it require energy that are
essential for composting (eg aeration, periodic turning).
8. Towards the end of the ‘termigradation’, termites can be harvested and used as food for
humans and/or livestock. They provide high-quality animal protein and are consumed by
several communities in South India and elsewhere. Moreover the termicast produced in
the method has fertilizer value.
9. The proposed method has been engineered to exercise process control. It also has
attributes of much greater versatility, speed, simplicity, and inexpensiveness. It is also
scalable.
10. Overall this method needs much lesser material and energy inputs than most bioprocesses
- even the relatively inexpensive ones like composting, vermicomposting or anaerobic
digestion. Nor does it generate gaseous, liquid, or solid waste.
We Claim:
1. A novel method for eco-friendly biodegradation of ligninous and other difficult-tobiodegrade
hard biowaste, said method comprising the following steps:
a. attracting naturally occurring termites by using baits and trails to an in-situ
termireactor specifically designed to harness said naturally occurring termites;
b. allowing the termites to biodegrade said ligninous and other difficult-tobiodegrade
hard biowaste in said termireactor;
c. harvesting the termites to remove the biodegraded biowaste.
2. The method as claimed in claim 1, wherein said termite species are selected from a)
subterranean termites, b) termites which forage on, or just below, the soil surface and c)
both above-ground and subterranean termites.
3. A novel in-situ termireactor for carrying out the method as claimed in claims 1 and 2, said
termireactor designed specifically based on the nature of the biowaste and the type of
termites used in the method.
4. A novel in-situ termireactor [ 1 ] for carrying out the method as claimed in claims 1 and
2, wherein the termireactor comprises:
a. one or more modules [ 2 ]; each module made of galvanized iron wire mesh [ 3 ]
and a protective covering lid [ 4 ] equipped with a handle [ 5 ];
b. a carry case [ 6 ] to transport the module, said carry case comprising a first [ 7a ]
and a second [ 7b ] larger surface area side and a first [ 8a ] and a second [ 8b ]
smaller surface area side;
said termireactor specifically designed to harness naturally occurring subterranean
termites to biodegrade said biowaste.
5. The in-situ termireactor [1] as claimed in claim 4, wherein each of said first [ 7a ] and
second [ 7b ] larger surface area side is fitted with a removable sliding panel [ 7c ] and
each of said first [ 8a ] and second [ 8b ] smaller surface area side is fitted with a fixed
panel [ 8c ].
6. The termireactors [1] as claimed in claim 4, further comprising a harvester assembly
comprising:
a. a first component [ 9 ] that fits into one of the said first larger surface area sides [
7a ] of the termireactor module and carries a light source [11 ],
b. a second component [10 ] that fits into said second larger surface area side [ 7b ]
of the termireactor, and contains the biowaste substrate.
7. A method for eco-friendly biodegradation of ligninous and other difficult-to-biodegrade
hard biowaste using an in-situ termireactor [1] as claimed in claims 2 to 6, said method
comprising the following steps:
a. charging the module [ 2 ] with the substrate to be processed and covering the same
with the lid [ 4 ] ,
b. porting thus charged modules of the reactor to the site of biodegradation in carry
case [ 6 ],
c. allowing the termites to act on the substrate to be processed,
d. installing the harvester assembly in below-ground pits with the charged modules
fitted in said harvester assembly,
e. removing the two sliding panels of the carry case and turning on the light source [
11 ] causing the termites present in the reactor module to move away from the
light source towards the component containing the biowaste substrate,
f. leaving the light source on till the termite migration is complete,
g. repositioning the removable panels in the carry case and disengaging the harvester
assembly from the module,
h. harvesting the biodegraded product from the reactor module by lifting the lid and
emptying the reactor contents.
8. A novel in-situ termireactor [12 ] for carrying out the method as claimed in claims 1 and
2, wherein the termireactor comprises of a module made of galvanized iron wire mesh
[13] on all sides having metal angles [ 14 ] to provide scaffolding for said wire mesh;
said termireactor specifically designed to harness naturally occurring termites which
forage on, or just below the soil surface to biodegrade said biowaste.
9. The in-situ termireactors [12 ] as claimed in claim 9, wherein said termireactor is sized
to maximize surface-area/volume ratio within the limiting condition that adequate
substrate depth be maintained to provide the requisite shading from sunlight as well as
humidity.
10. The termireactor [12 ] as claimed in claim 9, wherein the upper [ 15 ] surface of the
termireactor serves as a lid and can be swung open at the hinges by unfastening the
fasteners [ 17 ] and to charge/empty the reactor.
11. The termireactor [12 ] as claimed in claim 9, wherein two handles [18] are provided for
facilitating the transport of the termireactor.
12. A method for eco-friendly biodegradation of ligninous and other difficult-to-biodegrade
hard biowaste using an in-situ termireactor [12].
13. A novel in-situ termireactor [19] for carrying out the method as claimed in claims 1 and
2, wherein the termireactor is a cylindrical vessel made of galvanized iron wire mesh
[20 ] comprising a first flat surface [ 21 ] and a second flat surface [ 22 ] parallel thereto
having lids [ 23, 24 ] on both the first and second flat surfaces,
said termireactor designed to harness both above ground and subterranean naturally
occurring termites to biodegrade said biowaste.
14. A method for eco-friendly biodegradation of ligninous and other difficult-to-biodegrade
hard biowaste using an in-situ termireactor [19] as claimed in claim 12
a. when the termigradation is done using subterranean termites, the orientation of the
cylindrical vessel is kept vertical, with its flat surface touching the ground,.
b. when the termigradation is done using above-ground termites, the orientation of
the cylindrical vessel is kept side-ways.
15. The in-situ termireactor as claimed in any of the claims 3-13 wherein the termireactor can
optionally be fitted on all sides with trails comprising of narrow pipes of about 1 inch
diameter and 5 m length[ 25 ] partially filled with termite palatable material selected from
paper, saw dust, or similar material to attract scout termites.
16. The in-situ termireactors as claimed in any of the claims 3-14, wherein said biowaste
substrate is selected from the group comprising ligninous and other difficult-tobiodegrade
waste as coconut shell, thermocol pieces, lantana, ipomoea and cardboard.
17. A biofertilizer comprising the termicast produced by method of biodegradation of
ligninous and other difficult-to-biodegrade hard biowaste by harnessing naturally
occurring termites using an in-situ termireactor as claimed in any of the preceding claims.