FORM 2
THE PATENT ACT 1970
&
The Patents Rules, 2003
PROVISIONAL/ SPECIFICATION
(See section 10 and rule 13)
1. TITLE OF THE INVENTION
"Process for Continuous Production of Biogas from Biomass.'

2. APPLICANT
(a) NAME
(b) NATIONALITY
(c) ADDRESS

1. Kirloskar Oil Engines Limited
2. Gangotree Eco Technologies Pvt. Ltd. Indian Companies registered under the provisions
of the Companies Act,1956
1. Xaxmanrao.Kirloskar Path Khadki, Pune 411003, M.S. India. .
2. Flat no.l Susheeldatta Apts., Plot No.4, Padamarekha Society Karvenagar, Pune 411052, M.S., India.

3. PREAMBLE TO THE DESCRIPTION

PROVISIONAL
The following specification describes the invention.

COMPLETE
The following specification particularly describes the invention arid the manner in which it is to be performed.


6 OCT 1008

Technical Field
. Present invention relates to the process of production of biogas from biomass. More particularly it relates to a modified process in which the acidogenic and methanogenic micro organisms are retained in. their respective digesters. In the continuous process of biogas production, the two digesters are separated by introducing a balancing tank between them.
Prior art
Generation of biogas from biomass has been one of the options for getting over the progressively worsening energy crisis. Traditionally, this route has been only used for waste utilization or effluent treatment. Attention is continuously being given to find other routes to convert biomass into energy, such as, bio-diesel, ethanol and biomass gasification.
1. United States Patent 4022665
An improved two phase anaerobic digestion process in which an initial phase continually receives an organic feed for short detention times of less than two days under conditions which efficiently liquefy and breakdown the feed to lower molecular weight acids and other intermediates for conversion to methane. A succeeding phase is operated to treat the lower molecular weight acids and intermediates for detention times of about two to about seven days under conditions which efficiently lead to production of methane. The feed is loaded in the first phase at rates from about 1 to about 10 pounds of total organics per cubic foot per day; and the products from the initial phase are loaded in the succeeding phase at rates of about 0.1 to about 0.5 pounds total organics per cubic foot per day.


Drawbacks of Case One:
As there is no separation of Micro organisms, every time they get drained out through the output slurry. This limits the speed of the process.
2.United States Patent 4696746
A two phase anaerobic digestion process for production of methane from
organic carbonaceous material in which an active acid forming microbial
population is maintained in a first acid forming digestion phase and an active
methane forming microbial population is maintained in a second methane
forming digestion phase, the liquid effluent from the acid forming digestion
phase being passed to a first methane forming cJigester and gaseous product
from the acid forming digestion phase being passed to a second separated
methane forming digester for production of methane in the first and second
methane forming digesters of the methane forming digestion phase. The two
separated methane digestion phases provide increased overall methane
production.
Drawbacks of Case Two:
Micro organisms are not retained in their respective digesters. Every time
they get drained out with the output slurry, this limits the speed of the
process.
3. Indian patent no. 210309
A triphasic biomethanation process, to convert starch or sugary agricultural feed stock into a methane rich gas mixture for facilitating generation of biogas to be used as kitchen fuels, electrical power or transportation from renewable biomass in a cost-effective manner. The process brings about conversion of


starch-rich or sugar-rich biomass into methane through three stages, namely, hydrolysis, acidogenesis and methane formation. The present invention deploys enzymes/ physical/ microbial parameters to hasten the hydrolytic reaction in the first stage. It also deploys microbial consortia that have been enriched for a targeted feed in order to speed up the process of conversion. The formation of alcohol from starch is prevented, as a result of the consortia deployed, the conversion efficiency is substantially improved and the retention time is also reduced to cut the capital cost of the plant. Drawbacks of Case Three:
Though the process is divided into three stages, it is observed that no attempt has been made to retain the microbial consortia in the respective digesters. This limits the process speed, as every time the new bacteria needs to be generated.
4. U.S. Patent no. 5,529,692
A method for the biological processing of organic substances and more particularly for anaerobic biological hydrolysis for subsequent biomethanation, with pH value control, in the case of which the dissolved and/ or un dissolved organic substances supplied to a first reactor are at least subjected to slight acidification in such reactor, the major part of the un dissolved, at least partly acidified organic substances taken from the first. reactor are supplied to a second reactor for the performance of at least one solids hydrolysis step and the main part of the dissolved, at least partly acidified organic substances from the first reactor and from the second reactor are supplied to a third reactor for the performance of at least one methanation step.


Drawbacks of Case Four:
As there is no separation of Micro organisms for acid digester as well as for methane digester, the consortia get lost, every time they get drained out through the output slurry. This limits the work force for conversion of biomass into methane and thus limits the speed of the process.
5. U.S. Patent no. 4,781,836
An improved process for the biomethanation of an organic substrate includes treating the substrate in a first reactor to form organic acid anions, passing an aqueous preparation containing dissolved organic anions through an anion exchanger so that the organic acid anions are adsorbed and separated from the remainder of the aqueous preparation, desorbing the organic acid anions and passing the desorbed acids to a second reactor containing methanogenic bacteria which convert the acids to methane. In a preferred embodiment, a bicarbonate solution is produced in the second reactor and it is used to desorb the organic acid anions and regenerate the anion exchanger into the bicarbonate form. . Drawbacks of Case Five:
In this isolated case where introduction of an ion exchange column overcomes such a loss of microbial population, the feed streams have to be interrupted when the ion exchange resins get saturated with volatile fatty acids.
Deficiencies of prior art:
a. Most designs of biogas plants running in a continuous mode have exit streams that continuously drain microbial cells from the digesters.


b. Whereas the acidogenic micro-organisms are able to make up the cell
loss through fast multiplication, the methanogenic micro organisms
cannot do so, being slow multipliers.
c. Most digester failures result from depletion of methanogenic micro¬
organisms.
d. In an isolated case (5) where introduction of an ion exchange column
overcomes such a loss of microbial population, the feed streams have
to be interrupted when the ion exchange resins get saturated with
volatile fatty acids.
Objective of the present invention:
Objective of the present invention is to provide a method to avoid digester
failures because of depletion of methanogenic micro-organisms.
Further more object of present invention is to have a continuous, fast and efficient process for biomass conversion.
Statement of present invention
According to the present invention "Process forr continuous production of. Biogas from Biomass" acidogenesis and methanogenesis takes place in two separate digesters. This saves process time as well as saves micro organisms i.e. are acidogens and methanogens from draining out of the digester. By this method micro organisms used are subjected to optimum favourable conditions required for their activity and growth. Further a balancing tank is introduced between the two digesters which allow only acids formed in acidogenic digester to pass through and enter into the methanogenic digester.


Due care is taken that no microbial cells from acidogenic digester are passed into methanogenis digester. Rather microbes present in slurry are retained to their corresponding digesters after passing through the balancing tank.
Description of present invention
The foregoing objects of the invention are accomplished and the problems and shortcomings associated with prior art techniques and approaches are overcome by the present invention as described bellow in the preferred embodiment.
Present invention "Process for continuous production of Biogas from Biomass" involves two separate digesters connected though balancing tank. Contents of both the digesters are circulated through balancing tank with the help of separate channels. Said channels are made of dialyzing membrane. These channels only allow diffusion of volatile fatty acids coming into balancing tank through channel from acidogenic digester to the channel of methanogenic digester. Micro organisms are retained back into channels and are recirculated to their corresponding digesters. The volatile fatty acids are passed on to the balancing tank and thereafter to the methanogenic reactor by the concentration gradient created. Once in the methanogenic digester, the volatile fatty acids are converted to methane and carbon dioxide. Detailed descriptions of the preferred embodiment are provided herein; however, it is to be understood that the present invention may be embodied in various forms. Therefore, specific details disclosed herein are not to be interpreted as limiting, but rather as a basis for the claims and as a representative basis for teaching one skilled in the art to employ the present invention in virtually any appropriately detailed system, structure or matter.


The embodiments of the invention as described above and the methods disclosed herein will suggest further modification and alterations to those skilled in the art. Such further modifications and alterations may be made without departing from the spirit and scope of the invention;
Advantages of present invention
The method gets over the problems faced in the prior art of suboptimal conditions of a single digester and the risk of digester failure.
As the micro organisms are retained in their respective digesters, the process speed is improved. This results in reduction of capital cost, over the conventional digesters, for getting the same output.
As the process of biogas production is continuous i.e. without any break, we get the uniform and continuous source of energy.
Date 4th October, 2008
M.D. Bhate Agent for applicant