1. NOTES ON VISIT TO BIOGAS PLANT AT PADARTHA AT FOOD PARK
(As documented by S.Ananthanarayana Sharma, Ranjit Gupta Centre for
Documentation of Action Research, and further corrected by Mr. Saurabh
Mishra, Process Engineer, Biogas Plant, Patanjali BioResearch
Institute, Padartha Food Park, Hardwar and submitted to Dr.G.Paran
Gowda, Board member PBRI)
Time: 31
st
January 2013. From 12.50 to 14.30 hours
(Anant had spent a couple of days understanding the equipment flows,
earlier to this discussion).
People: -
Mr. Saurabh Misra, Process Engineer, PBRI
Mr. Aman Kumar, Manager (Operations) PBRI
Mr.Sanjay Rachelli, Officer - Projects,of Kirloskar Integrated
Technologies Limited (KITL) for a very brief discussion
CONTEXT TO THE VISIT:
S.Ananthanarayana Sharma,(Anant hereafter) Aman Kumar (Aman hereafter)
and Saurabh Mishra (Saurabh hereafter) had been involved in collating
the documents for the No Objection Certificate (NOC) from the
Uttarakhand Pollution Prevention and Control Board. This visit, was in
the nature of an orientation one - to get to understand the
technologies behind the newly erected 6000 cubic metre plant. Also
Anant had worked with smaller plants,(60 cubic metres)- as a part of
the biogas program with the milk cooperative AMUL in 1985-87. The
visit was to update his knowledge and pass on some of his insights to
Aman and Saurabh.
PLANT OPERATIONAL PLANNING:
KITL had planned the plant initially around some projects of organic
waste that would be generated as a result of the various food
processing industries of Patanjali Food and Herbal Park. However the
actual production and the consequent organic waste generated had not
been as per projections. The current thinking appears to be to shift
to purchased cow dung as feedstock - to make up for the deficit in
availability of raw material from the food park manufacturing units.
As per the NOC submitted, around 120MT was the planned input organic
waste. Presently around 20MT of organic waste can be expected from
Padartha food park operations. The present planning is to purchase
some 100 MT of cow dung per day for the plant operations.
The original plan envisaged production of around 0.6 to 1 MW of power,
from the scrubbed methane. However, the present operational planning:
is to delay commissioning of the electric power generation unit. The
scrubbed methane is to be fed by a pipe to the boiler unit, a few
hundred metres from the plant: as fuel for boiling water to convert to
steam for plant operations in the Food Park.
The planning for biofertiliser, did not appear to be completely
thought through in the original planning. There were some vague
references to adding rock phosphate to dried slurry to make
biofertiliser. The Patanjali Bio Research Institute (PBRI) has
successfully demonstrated a business model around sale of
biofertilisers. These live experiences are in the process of being
incorporated in the manufacturing design process - in terms of a plant
to reduce moisture from the slurry, and then transferring the contents
to open air lagoons, for drying - before mixing and packing.

2. The observations are presented, in terms of the movement of the
material, from the input cow dung and organic waste - to the output
methane and slurry for biofertiliser manufacturing.
Various photographs taken, are attached in a separate document which
can be cross referred to for clarification.
INLET TANK
There is a tin shed, with a large pit - which has an approximately 5
MT capacity mild steel .inlet tank: with a pipe and pump connected to
the mixing tank. The following action points can perhaps be discussed.
1. Is there a necessity for specifying dimensions for the organic
waste /biomass that is used to be feedstock? Example -
Saurabh’s statement that Aloe Vera waste should be pulverised
to less then 1mm size and Amla (Phyllanthus emblica - Indian
Gooseberry) should be chopped.This is necessary for proper
digestion in digester and smooth movement of slurry by pumps
installed.
2. If there is a scientific/technical merit in these statements,
is there a need for a “pre treatment shed”- with necessary
pulverising, chopping, and crushing equipment? The shed would
also be required for temporary storage and protection during
rains..
3. There are visible rust spots on the tin shed roof. KITL has
been apparently asked by Saurabh to paint the shed before
formally handing over the pant.
PIPING AND PUMP FROM INLET TANK MIXING TANK
The piping and the pump has been installed. All the pumps for shifting
the raw material from the inlet tank to mixing tank have been
completed as per Saurabh. The following action points can be
discussed?.
1) Water line has been s installed for moisturizing the feed in
inlet tank.Are there some technical norms of moisture content -
to facilitate easy flow of material from the inlet tank to mixing
tank?
2) As per Saraubh “flow parameters” are dependent on total solids
present in feed. During the commissioning period, the technical
specifications-like How much flow per hour? At what
concentration (in terms of moisture content)? should be
standardised.
MIXING TANK
Mixing tank is to be commissioned The water pipes for hot water has
been painted in black, to enable absorption of heat. There is a
submersible pump, which is installed near the water treatment plant
(which is a few hundred metres away) which is successfully pumping
water into the mixing tank. Some action points for discussion?
1) Technical specifications of mixing tank capacity, water
required? Biodigester will work on 5 to 6% T.S.We need to mix
water according to feed, accordingly.
2) Any provision of backup for water pumping, in case the existing
pump fails, in between mixing operations? There are two
submersible pumps. The necessity for another backup submersible
pump can be perhaps taken up after plant commissioning, depending
on the performance of the existing pump.

3. BUFFER TANK
The buffer tank is holding some cow dung and water mixture. There
seems to exist some technical norms, as per Saurabh, as under -
• pH value - 7.0
• Temperature - 35 to 42 degrees Celsius
• Dilution - Total Solids -6-8%
Some specific action points for discussion.
1) No written technical specifications/operations manual on mixing
tank capacity, operations, safeguards, etc. Saurabh stated that
KITL will give all the manuals during handing over of plant after
successful commissioning-which needs to be ensured.
2) There does not seem to exist any diagrams for piping, wiring,
etc. Saruabh states that KITL will give all the diagrams of
piping during handing over of plant after successful
commissioning- which needs to be ensured..
LABORATORY
A laboratory needs to be equipped to test the material, at various
process points, for pH value, temperature, Total Solids %age, BOD,
COD, etc. An action point for discussion?
1) The list of equipment, methods of testing, methods of drawing
samples, protocols for information sharing, etc Saurabh states
that KITL will give all the details.- which needs to be received
in some sort of time frame- to enable preparation of SOPs for
sampling, and analytical measurements.
PIPING FROM BUFFER TANK TO DIGESTER
Piping seems to have been commissioned to pump the initial cowdung
mixture to the digester.
DIGESTER
The digester is stated to have a capacity of 6000 cubic metres. There
are many pipes going in and out of the digester, as also around the
digester.
On top of the digester:
A number of pipes have been projected from the digester’s head. This
includes a yellow painted, large (8 inch diameter) pipe, which is
stated to be a sort of a flare? Another 6 inch diameter pipe, painted
white is stated to be a vent?
A water tank (with around 2000 litres capacity) has been mounted. This
tank is designed for cooling the stirring motors, as per Saurabh.
There seems to be some pipes which according to Saurabh, are supposed
to flow gas to some gas pressure gauge (manometer)
A large motor has been mounted exactly on top of the digester, which
is stated to be the machine for stirring the mixture within the
digester.
Another blue painted valve has been mounted. Saurabh stated that this
was a “Breather valve”, , which purpose is for safety.
A metal frame has also been erected, which function is stated to be
that of a lightening arrestor.
There is a complicated maze of piping, leading from the digester to
the degasifier and to the floating dome holder. Some pipes seem to be
for recycling material?
Bottom of digester
There are eight pipes, coming out of the digester at different
heights. These have been stated by Saurabh to be “sampling ports” for
taking samples of the digested slurry within the digester?

4. There is some gauge which is stated to be a pressure metre?
There exists some colour coding of pipes - in yellow, green, red, etc.
Output of digester
Usually biogas digesters have two main output - METHANE and SLURRY.
It appears that a large yellow painted pipe leading to the gas holder,
is for transporting methane gas?
Slurry seems to be led out by some black painted pipe? There is also
some complex piping from the digester to the degasser? This could
probably be slurry, which will overflow to the degasser, and then led
back after recycling?
Some action points for discussion with KITL during handing over..
1) Piping diagram, alongwith block/process flow diagram exclusively
for the digester.
2) Instrumentation in the digester.
3) An engineering diagram, with another specific cross section
diagram.: clearly specifying dimensions, and indicating the name
of the various parts/components installed.
4) Standard Operating Procedures and Operating manual for digester.
This should include simple diagrams with photographs, explaining
the various gauges, pipes, and pumps installed on the digester
walls and top.
DEGASSER
There is a tall hollow tubular column, installed next to the digester.
This was stated to be the degasser. This could be also some sort of a
decision point - for segregating slurry - back to the digester for
processing, and to the biofertiliser unit. There appeared to be a
green pipe, for connecting the digester and the degasser and red pipe,
for connecting the biofertiliser unit with the degasser?
It appears that the red pipe is the sole source of supply to the
biofertiliser unit (called separation unit?).(Known as decanter )
The list of pipes leading out of the degasser seems to be as under-
1) Four outlet pipes to mixing tank (?)
2) Big green pipe to digester
3) Big green pipes let to floor, presumably to effluent treatment?
4) Red pipe to to decanter for liquid solid separation. unit (for
biofertiliser?)
The degasser seems to be some new technology not commonly used in the
smaller biogas plants that are routinely installed. Hence some action
points for discussion with KITL at time of commissioning..
1) A short technical note, explaining clearly what is the “technical
value addition” of this degasser. And what is the technology, and
how does this work? Saurabh states that the primary function is
for managing overflow of digester.
2) An engineering diagram, with another specific cross section
diagram.: clearly specifying dimensions, and indicating the name
of the various parts/components installed.
3) Piping diagram, and instrumentation diagram exclusively for the
degasser. .
4) Standard Operating Procedures and Operating manual for the
degasser. This should include simple diagrams with photographs,
explaining the various pipes, going in and out of the degasser.
METHANE GAS HOLDER
There are two gas holders. This paragraph is on the first gas holder,
from the digester.

5. A big (8 inch diameter) yellow pipe leading from the digester to the
gas holder, seems to be the sole source of input- which could be
methane gas? There seems to be some white painted Mild Steel tank -
which Saurabh stated was for removing moisture from gas before the
pipe enters the holder. There is a black V shaped pipe, outside the
gas holder, which too according to Saurabh could be for removing
excess water from gas holder. Some action points for discussion with
KITL.
1) Saurabh stated that the biogas holder will hold the raw methane
gas produced from fermentation process and supply the gas to the
scrubber with constant pressure. Air blower regulates the
variation between gas input and output, thus keeping the gas
pressure inside the biogas holder at a constant level. An
engineering diagram, with another specific cross section
diagram.: clearly specifying dimensions, and indicating the name
of the various parts/components installed.
2) Piping diagram, and instrumentation diagram exclusively for the
degasser. .
3) Standard Operating Procedures and Operating manual explaining the
various pipes, going in and out of the gas holder.
BLOWERS
Two large pumps have been installed next to the first gas holder. This
could be probably for pumping methane gas to scrubber.
Some action points for discussion with KITL.
1) A short technical note, specifying the precise nature of, the
regulation of the variation between gas input and output: to
keep the gas pressure inside the biogas holder at a constant
level Some numbers regarding the optimal pressure, method of
measurement, regulation of blower speed?
2) An engineering diagram, with another specific cross section
diagram.: clearly specifying dimensions, and indicating the name
of the various parts/components installed.
3) Piping diagram, and instrumentation diagram exclusively for the
blowers .
4) Standard Operating Procedures and Operating manual explaining the
various pipes, going in and out of the gas holder.
SCRUBBER
The scrubber is stated to be a “patented technology” developed by
KITL. The scrubber is a tall (10 metres) tubular column, with a base
of around 32 inches diameter. It appears to be made of fibre glass.
Two large 6 inch diameter yellow painted pipes: presumably are for
piping methane gas. There is a 3 inch diameter HDPE pipe with a valve.
There are two pumps. Saurabh said that “elemental sulphur” was to be
removed through this scrubber.
There is water tank, presumably for storing water from the Reverse
Osmosis (RO) plant. Apparently the planning for the food park to
provide RO water of around 5 cubic metres per day. The piping from
the RO plant to the scrubber has to laid by PBRI.
Some action points for discussion with KITL
1) The purpose of the scrubber, as per Saurabh appears to be for
removing the H2s which can corrode the engine if not separated.
Some numbers regarding the expected range of moisture content in
the input gas, the technical value addition, in terms of
moisture removal, and the output moisture level in the methane
gas could be forecasted? And later tested during commissioning?

6. 2) An engineering diagram, with another specific cross section
diagram: clearly specifying dimensions, and indicating the name
of the various parts/components installed.
3) Piping diagram, and instrumentation diagram exclusively for the
scrubber .
4) Standard Operating Procedures and Operating manual explaining the
various pipes, going in and out of the scrubber.
5) If possible, the patent document filed (which is a public domain
document) can be obtained to get some more details?
OTHER UNITS
There is a second methane gas holder, presumably to store
desulphurised methane from the scrubber. The scrubbed methane will
presumably sent by a newly laid pipe, to the boiler unit, which is
around 300 hundred metres away.
The electricity generation unit has some of the machinery installed.
Apparently this is not going to be commissioned with the digester.
Some action points for discussion with KITL.
1) After production of gas and testing of all systems, the
specifications of the methane gas that is to be sent to the
boiler, should be clearly stated.
2) A note explaining how the electric generation plant works in
theory. Which can be used later for experimentation by reknowned
scientists like Dr.G.Paran Gowda or IIT (Roorkee/Delhi)
professors

7. POSSIBLE BLOCK DIAGRAM FOR BIOGAS PLANT AS PER LIMITED UNDERSTANDING OF S.ANANTHANARAYANA SHARMA
BASED ON THE OBVERSATIONS ON 31 JANUARY 2013
Inlet tank
Mixing
tank
Buffer
tank
BIOGAS DIGESTER
DEGASSER
SEPARATION
UNIT FOR
BIOFERTILISER
METHANE
GAS Holder
Blowers
SCRUBBER
Scrubbed
Methane to
boiler