Title of Invention

DESIGN AND DEVELOPMENT OF LUBRICITY ADDITIVE DOSING SYSTEM FOR OPERATION OF BHEL-GE GAS TURBINES ON NAPHTHA FUEL WITH FLEXIBILITY TO OPERATE ON VARIOUS LUBRICITY ADDITIVES

Abstract The present invention is provided with an improved flexible lubricity additive dosing system adaptable to a gas turbine operating on naphtha fuel, comprising an unloading device having a portable motor driven barrel pump for transferring lubricity additive from a barrel to a storage tank, the storage tank being operably connected to the unloading device via a discharge hose, the barrel pump is connected to the portable motor drive via a flexible power cable, the storage tank provided with instrumentations for auto-change-over of gas turbine to alternate fuel, in response to alarming signals generated by the instruments provided in the storage tank based on the available levels of the lubricity additives in the tank and at least two motor driven dosing pumps for metering and dosing a predetermined quantity of lubricity additives into a fuel supply device of the gas turbine and a pulsation dampener for smoothening the additive flow into the system and a flow meter to measure the flow rate of lubricity additive to the gas turbine and providing a flow signal to a dosing control device; and a control device for calculating the dosing rate based on instantaneous naphtha flow rate into the gas turbine, the device transmitting corrective signals representative of the flow-rate once the flow-rate measured by the flow-meter mismatches the calculated dosing rate.
Full Text


FIELD OF THE INVENTION
The present invention relates to an improved flexible dosing system for injecting
"Lubncity additive" adaptable to Gas Turbines operating on Naphtha fuel. The
improved system can adapt several quality of "Lubricity additives" available in
the rnerket
Gas Turbines are required to operate on various types of fuels.
Whet ever,Naptha fuel is readily available and offer significant advantages in
availability and cost, becomes attractive for use as fuel in Gas Turbine systems.
While. Naphtha fuel may offer significant advantages, this fuel has the
characteristic of low lubricity. Accordingly, this particular characteristic of
Naphtha fuel does warrant additional treatment to assure long life of the Gas
Turbine, particularly of the fuel system components of the turbine
The operating life of a typical fuel system of the Gas Turbine depends on the
lubricating capability of the hydrocarbon fuels used in the Gas Turbine to protect
bearing and its mating surfaces.
To distribute the liquid fuel flow equally to the combustion chambers, prior art
Gas Turbines use mechanical flow dividers that have very tight tolerance of
internal mating parts to meter the fuel flow to the multiple combustion


chambers, ihese flow dividei* have been very successful n# providing a very
tight tolerance of flow division needed to provide uniform distribution of
temperatures from the combustion system and into the turbine section. As on
today, flow dividers are an essential feature of liquid fuel-fired gas turbines.
For the Gas Turbines operating on Naphtha fuel, a "Lubricity additive* is
generally to be dosed or injected into the Naphtha fuel for raising the lubricity
parameters to such ievels which are acceptable to the flow dividers.
The following operational constraints also need attention with respect to
selection of the dosing rate of the "Lubricity additive" into Naphtha fuel:-
(i) If the injection rate is too high, gumming of the flow divider will
occur and the flow divider will stop gripping the turbine,
(ii) If the injection rate is too low, the bearings of the flow divider will
seize, also tripping the turbine,
(iii) Lubricity properties of Naphtha formulations vary depending on the
particular production process adopted by different manufacturers,
(iv) the cost of "Lubricity additive* is considerably high in Gas Turbine
based plant, and any reduction in additive injection rate if achieved,
will lead to significant savings in operational cost of the plant.
Traditionally, Hitec-580 is used as the "Lubricity additive*. Tests have shown that
riitec-580 additive injection to produce a concentration of 60-75 ppm [weight by
weight] of Naphtha fuel flow rate into the Gas Turbine is the best overall rate.
Presently, the following »s recommended by the Gas Turbine manufacturers for
the injection of "Hitec-580 additive" for opeiation of Gas Turbines operating on
Naphtha fuel.


(i) I he initial flow rate of "Hitec-M>0 additive* is selected to provide a
concentration of 75 ppm [weight by weight] of Naphtha fuel flow
rate into new Gas Turbines, operating on Naphtha
fii) The flow divider shall be removed, disassembled and inspected at
frequent intervals for measuring the rate of deposition. If the initial
concentration of the additive results in excessive deposits, the
injection rate shall be reduced to 60 ppm [weight by weight]. The
evaluation process shall be continued and if the excessive deposits
continue to form, the injection rate shall further be reduced while
ensuring that there is no undue "wear" taking place m the bearings
of the flow divider.
(iii) Under no circumstances the dosing rate shall be lower than 30 ppm
^weight by weight], below which the resultant wear will lead to
very short life of the flow divider,
(iv) The cost of additive can be minimized by consistent inspection,
evaluation and tuning of the additive dosing rate to a minimum
extent required
In addition to Hitec 580, various other "lubricity additives" under different brand
names, are available for Gas Turbines operating on Naphtha fuel. Gas Turbine
users are aiso preferring the available choice in selection of "lubricity additive" to
procure the same at competitive prices thus leading to reduction in plant
operating costs.

Accordingly, various available additives have also been tested by the Gas Turbine
manufacturers, However, in line with the test results, the recommended
maximum and minimum dosage rate of various types of additives differ from
brand to brand, compared to the standard recommended dosaqe rate of 30-75
ppm for Hitee-580.
The details of various "lubricity additives" along with their recommended
minimum to maximum dosage rate is as per the following table.



From the above table, it can be construed that the 'Lubricity auditive* dosing
system - for operation of Gas Turbines on Naphtha fuel generally needs further
special treatment as below:
(i) The dosage flow rate of "Lubricity additive" shall be in accordance
with Naphtha fuel flow rate into the Gas Turbine on weight to
weight basis. In correspondence with the variations of load on the
(ias Turbine, the Naphtha flow rate into the Gas Turbine also
varies. The Gas Turbine generally responds instantaneously to any
variation of bad which is not: predictable. Hence, the "Lubricity
additive' dosing system need to be designed in such a way that the
flow rate of "Lubricity additive" should be instantaneously changed
in registration with the variations in flow rate of Naphtha fuel into
the Gas Turbine.
For typical Gas Turbines, the Naphtha flow rate depends on its density and
Calorific value. The density of Naphtha varies from 0.65 to 0.75 Kg/Lit. The
calorific value of Naphtha fuel is close to 10,000 Kcal/Kg. The turn down
requirement of Naphtha flow rate into the Gas Turbine is 41 on volume basis,
couesponding to the maximum and minimum flow rates of Naphtha into the Gas
Turbine.
(ii) In addition, the dosage rate of "Lubricity additive" in terms of ppm
is variable for a plant depending on an outcome of the balance of
wear and plugging with respect to the individual Naphtha
formulation used in the plant. Accordingly, the dosage rate of
"Lubn<: additive varies from ppm to depending on> the biand of "lubricity additive "selected.


The dosage rate of "lubricity additive" in terms of ppm is an
outcome of inspection of the dismantled flow divider and will be
maintained constant till the next inspection
However, the lubricity dosing system shall be capable of meeting
the probable variation in dosing rate in terms of ppm,in addition to
the variation in Naphtha flow due to changes in loads on Gas
Turbine.
For a typical Gas Turbine, corresponding to maximum and
minimum dosing rate variation of 100 ppm to 25 ppm, the turn
down requirement of "Lubricity additive" dosing is 4:1 on volume
basis
Further, the lubricity additive dosing rate is on weight to weight
basis with respect to Naphtha flow into Gas Turbine. The weight of
"lubricity additive" depends on the density of brand of additive
used. Accoidingiy, the turn down requirement of "Lubricity
additive" for a density variation of the additive of 0.8748 to 0.94 is
1.1:1, on volume basis,
Accordingly, for a typical Gas Turbine, the combined turn down
requirement of "Lubricity additive" is 17.6:1, meeting variations in
Gas Turbine load including variations in ppm level of dosing, and
variations in densities of lubricity additives.


Hence, the lubricity additive dosing system should be capable of
matching the wide variations in the "Lubricity additive" flow rate
required.
(iii) As the dosing quantity is very smali and trie same is sensitive in
terms of choking/wear of the flow divider, the dosing rate shall be
accurate Hence, there should he a feed back system to ensure that
the "Lubricity additive' dosage is as per the requirement only.
Further, the components of the system shall be accurate enough to
ensure accurate dosing,
Iiv) The viscosity oj "Liirbicity additive" is varying from as low as 20 Cst
to 256 Cst. depending on the brand of "Lurbicity Additive"
chosen.Normally, there will not be any operational problem for
dosing pumps for a lubricity level of 20 Cst. However, the dosing
pumps shall be capable of operating at high viscosity level of 256
Cst
(v) As the "Lubricity additive" is available in the standard barrels, there
shall be suitable provision for unloading the same into the system.
The "Lurbicity Additive" dosing systems- for the typical Gas Turbines operating
on Naphtha fuel in practice are normally designed tor one particular "Lubricity
Additive" ie.t Hitec-580 and for a particular dosing rate. These systems constitute
gear type "Lubricity additive* dosing pumps with automatic speed control of the
pumps with variable frequency drive.
The above system has a limited turn down of 7:1 only. Hence, this system can
not cater to dosage rates, densities, where a minimum turn down of 17 6:1 is required.


Further gear pumps have a ttindeiity fui lower throughput the ViitOiiity Ci
fluid is higher, thus calling for higher capacity of the pump when handling higher
viscosity Lubuciry additive", which further calls for much higher turndown
requirement.
In these systems manual unloading of "Lubricity additive" into the system
storage tank is practiced,, which is labor intensive,
Objects of the Invention;
It is therefore an object of the invention to propose an improved dosing system
for injecting lubricity additive adaptable to gas turbines operating on naphtha
fuel.
Another object of the invention to propose an improved dosing system for
injecting lubricity additive adaptable to gas turbines operating on naphtha fuel
which eliminates the disadvantages of the prior art
A further object of the invention to propose an improved dosing system for
injecting lubricating a&Mi^ adaptable to gas turbines operating on naphtha fuel
which is capable to cater for the variations in viscocities of different types of
available lubricity additives.
A still further object object of the invention to propose an improved dosing
system for injecting lubricity additive adaptable to gas turbines operating on
naphtha fuel which provides mechanized unloading of lubricity additives to the
storage tank of the system.


An yet another object of the invention to propose an improved dosing system for
injecting lubricity additive adaptable to gas turbines operating on naphtha fuel
which is faster, economic and accurate
Summary of the invention
Accordingly, there is provided an improved flexible lubricity additive dosing
system adaptable to a gas turbine operating on naphtha fuel, comprising an
unloading device having a portable motor driven barrel pump for transferring
lubricity additive front a barrel to a storage tank, the storage tank being
operably connected to the unloading device via a discharge hose, the barrel
pump is connected to the portable motor drive via a flexible power cable, the
storage tank provided with instrumentations for auto-change ■• over of gas
Turbine to alternate fuel, m response to alarming signals generated by the
instruments provided in the storage tank based on the available levels of the
lubricity additives in the tank. At least two motor driven dosing pumps are
provided for metering and dosing a predetermined quantity of lubricity additives
into a fuel supply device of the gas turbinp A pulsation dampener is arranged
for smoothenmg the additive flow into the system. A flow meter is disposed to
measure the follow rate of lubricity additive to the gas turbine and providing a
flow signal to a dosing control device, A control device is operably connected for
calculating the dosing late based on instaneous naphtha flow rate into the gas
turbine, the device transmitting corrective signals representative of the flow-rate
once the flow rate measured by the flow meter mismatches the calculated
dosing rate


BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
1. Figure 01: is schematic diagram of on-base liguid fuel system for a typical
Gas Turbine.
2. Figure 02: is schematic diagram of an improved flexible -"Lubricity
additive'7 dosing system"- for a Gas Turbine operating on Naphtha fuelf
according to the invention.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE
INJCENJION:
As shown in figure-2, the improved flexible "Lubricity additive" dosing system-
comprises the following components:
- an Unloading device (2,3,4);
a Storage Tank. (5);
- atleast two Motor driven dosing pumps (6);
a Pulsation Dampener (7) ;
- a Flow meter (8);
■ Inter connecting piping and instrumentation circuit; and
a Control device having Variable Frequency Drives.
The function and detailed descriptions of above components is as given below:
1,0, 0, Unloading device (2,3,4)


1.1.0. Function:
Normally, the "Lubricity additive" is available \r\ standard 200/250 liters
banels(l) (he function of the unloading device is to transfer the "Lubricity
additive" from the barrel (i) to a storage tank (5) of the "Lubricity additive'
dosing system.
1.2.0 Components Description:
Atieast one portable motor driven barrel pump (2) with a discharge hose (4) and
a flexible power cable with a plug arrangement is considered as a part of the
"Lubricity additive" dosing system.
(n case the level of the storage tank (5) is low, alarm will be generated in the
control room for operators intervention for unloading of "Lubricity additive' in to
the storage tank (5) of the dosing system, using the barrel pump(2). The pump
(2) can unload the banel (1) in about 5 minutes.
The storage tank(5) has sufficient reserve capacity for a dayf tiii the 'Lubricity
additive" is replenished manually.
2.0*0, Storage Tank (5)
2.1.0 Function:
""Lubricity additive" for ten days operational requirement of the Gas Turbine can
be accommodated in the storage tank (5).

2.2.0. Components Description:
Aileast one 450 titers storage tank (5) is envisaged for a Gas Turbine (10) The
tank (5) is provided with required levei instruments for:
(i) alarming the operator in case of low level in the tank (5) for
replenishment of "Lubricity additive*,
(ii) auto change-over of operation of the Gas Turbine (10) to alternate fuei
and to trip the dosing pumps (6) in case of low-low-level in the tank
(5) It is not safe for the operation of Gas Turbine on Naphtha fuel
system (U) without dosing of "lubricity additive*. Further, non~
occuuence of level iow-iow alarm will act as a start permissive for
starting the dosing pump (6).
3.0.0. Motor Driven Dosing Pumps (6):
3.1.0. Function:
To dose the required quantity of "Lubricity additive" into Gas Turbine fuei supply
system, according to the fuel flow rate, while the Gas Turbine is operating on
Naphtha fuel.
3.2.0. Components Description.
As the dosing requires accurate metering, positive displacement plunger pumps
are ideal choice. Fuither, with plunger pumps it is possible to have a higher turn
down in flow rate by combined effect of stroke length variation along with
variable speed operation of the pump.

Accordingly,, atieast two motor driven plunger type reciprocating pumps (1
working f 1 standby) of suitable capacity and head are considered for the
system.
Blither, check valves ^witti double ball witliout spring) ate envisaged as a special
design in these pumps (6), to cater to higher viscosity requirement of 256 Cst.
These check valves are suitable for operation on low viscosity of 20 Cst also.
The pump (t>) has manual stroke iength setting provision with a turn down ration
of 10:1. ie., the stroke length can be varied from 10% to 100%. The flow rate of
the. pump is proportional to the stroke length set.
Further, for a given stroke iength setting, the flow rate can be varied by
changing the speed of operation of the pump (S).
4.0.0. Pulsation Dampener: (7)
1.3.0 Function:
To smoomen the pulsating flow in the system
4.2.0. Components Description:
As the flow characteristic of a reciprocating pump, is pulsating, a pulsation
dampener (?) is provided on the discharge line of the pumps (6), so that
smoother flow is ensured in the downstream system Further, the flow meter(8)
provided in the system also requires a non-pulsating Row for effective operation.

5.0.0 Flow Meter: (8)
5,1.0 Function:
To measure and indicate the flow rate of "Lubricity additive* being dosed into
Gas Turbine Fuel system and to provide the fbw signal to the dosing control
device (9).
6.0.0. Interconnecting Piping and Instrumentation:
6.1.0. Function:
All the required inter connecting piping and instrumentation like safety valves,
gauges and transmitters are provided as shown in Rgute-2 for monitoring and
safe operation of the system.
7.0,0. Control device with Variable Frequency Drives (9);
7.1.0. Function:
The control device of "Lubricity additive" dosing system, does the following
functions, namely.
(i) Control the speed of the dosing pumps(6), based on signal from a
feed back means (not. shown)
(li) Auto start of the standby dosing pump (6)r in case of failure of the
running pump (6).
(iii) Other controls

(i) Controlling speed of the dosing pump* (6)
The dosing pump (6) has manual stroke iength setting provision with a turn
down ration of 10:1 ie., the stroke iength can be varied from 10% to 100%. The
flow rate of the pump (6) is proportional to the stroke length set.
Further, for a given stroke iength setting, the flow rate can be varied by
changing the speed of operation of the pump.
The initial stroke iength of the pump (6) is set as per the "ppm level'of dosing
required and the flow rate of the pump (6) is further tuned by automatic speed
variation of the pump based on the feed back signal with respect the Naphtha
flow rate into Gas Turbine (10), which depends on the load on the Gas Turbine
at that instance,
The initial manual stroke length setting for various ppm levels of dosing and for
various "Lubricity Additives" is given in the following table for a typical Gas
Turbine. For this application, the selected capacity of the pump is 0-2 Liters per
hour,




Out of the total turn down requirement of l/.u.t, once the stroke length of
dosing pump (6) is set based on Naphtha fuel density and required ppm level of
dosing, the "lubricity Additive* flow rate only needs to be controlled with respect
to Naphtha fuel flow rate into Gas Turbine corresponding to operating load on
the Gas Turbine. The remaining required turn down for meeting this requirement
is in the range of 4:1.
Variable Frequency Drives are considered as part of a power supply system to
the motors of the dosing pumps (6) for automatic changing the speed of the
pomp (6), with respect to venations in Naphtha fuel flow into Gas Turbine (10),
variable frequency drives have a turn down of 7;i for changing the speed of the
metering pump, which is well above the required turn down of 4:1.
The Naphtha flow rate into the Gas Turbine (10) is measured by a Naphtha flow
meter (14). The Naphtha flow signal is fed into a "Lubricity additive: dosing
control device (9).
This control device (9) constitutes a dedicated PLC based pane! or the plant DCS.
In the control device 'Lubricity additive* dosing rate is calculated for a given
*ppm level'based on instantaneous Naphtha flow into the Gas Turbine (10) and it
is used as a variable set point for the control op Lubricity additive" dosing rate.

The "Lubricity additive" being dosed into a Gas Turbine fuel system (15) is
measured by the "Lubricity additive" flow meter (8) and compared with the set
flow rate, and a corrective signal will be provided to the variable frequency drive.
Based on this signal, the variable frequency drive will vary the frequency of
power supply to the motor of the dosing pump (6), thus changing the speed of
the pump (6) and the flow rate of the dosing pump (6) is tuned to the
requirement, by the control device (9).
(ii) Auto Change over of dosing pumps
Corresponding to the "Lubricity additive" dosing flow required, as calculated by
the control device (9), a flow level at 20% lower than required is identified by
the control device as low rate of closing, In case of low rate of dosing, due to
failure of running of the dosing pump (6)r as measured by the "Lubricity
additive" flow meter (8), the control device (9) will start the stand-by pump (6)
and trip the running pump (6), thus ensuring a continuity of dosing. In case the
>tand-by pump (6) does not start in pre-set time, that is low-flow condition
prevails, a signal will be provided to the Gas Turbine control system (12) to
change over to alternate fuel by actuating a change-over valve (13), for safe
operation of the Gas Turbine (10).
(ii) Other controls.
The control system provides additional controls as required namely,
(a) Start permissive for Gas Turbine to start on Naphtha fuel only
after ensuring "Lubricity additive* dosing system is operative.
(b) Other alarms for monitoring the system.

WE CLAIM
1. An improved flexible lubricity additive dosing system adaptable to a gas
turbine operating on naphtha fuel, comprising:
- an unloading device (2,3,4) having a portable motor driven barrel
pump (2) for transferring lubricity additive from a barrel (1) to a
storage tank (5), the storage tank (5) being operably connected to
the unloading device via a discharge hose (4), the barrel pump (2)
is connected to the portable motor drive via a flexible power cable
(3), the storage tank (5) provided with instrumentations for auto-
change-over of gas turbine to alternate fuel, in response to
alarming signals generated by the instruments provided in the
storage tank (5) based on the available levels of the lubricity
additives in the tank (5);
- atleast two motor driven dosing pumps (6) for metering and dosing
a predetermined quantity of lubricity additives into a fuel supply
device of the gas turbine (10);
- a pulsation dampener (7) for smoothening the additive flow into
the system;
- a flow meter (8) to measure the flow rate of lubricity additive to
the gas turbine (10) and providing a flow signal to a dosing control
device (9); and
- a control device (9) for calculating the dosing rate based on
instantaneous naphtha flow rate into the gas turbine (10), the
device (9) transmitting corrective signals representative of the flow-
rate once the flow-rate measured by the flow-meter (8)
mismatches the calculated dosing rate.

Characterised in that the system is capable of dosing lubricity additive for
multiple rates of lubricity additive and for multiple loads of gas turbine by
controlling the rate of flow through controlling the speed of the dosing pumps
without interruption.
2. The system as claimed in claim 1, wherein the operating speed of the
dosing pumps (6) is controlled by atleast one variable frequency drive
allocated to a power-source providing power to the motors o the pump
(6), the variable frequency drive being capable of automatically changing
the speed of the pumps.
3. An improved flexible lubricity additive dosing system adaptable to a gas
turbine operating on naphtha fuel as substantially described and
illustrated herein with reference to the accompanying drawings in Fig.2.


The present invention is provided with an improved flexible lubricity additive
dosing system adaptable to a gas turbine operating on naphtha fuel, comprising
an unloading device having a portable motor driven barrel pump for transferring
lubricity additive from a barrel to a storage tank, the storage tank being operably
connected to the unloading device via a discharge hose, the barrel pump is
connected to the portable motor drive via a flexible power cable, the storage
tank provided with instrumentations for auto-change-over of gas turbine to
alternate fuel, in response to alarming signals generated by the instruments
provided in the storage tank based on the available levels of the lubricity
additives in the tank and at least two motor driven dosing pumps for metering
and dosing a predetermined quantity of lubricity additives into a fuel supply
device of the gas turbine and a pulsation dampener for smoothening the additive
flow into the system and a flow meter to measure the flow rate of lubricity
additive to the gas turbine and providing a flow signal to a dosing control device;
and a control device for calculating the dosing rate based on instantaneous
naphtha flow rate into the gas turbine, the device transmitting corrective signals
representative of the flow-rate once the flow-rate measured by the flow-meter
mismatches the calculated dosing rate.

Documents:

190-kol-2006-abstract.pdf

190-kol-2006-claims.pdf

190-kol-2006-correspondence.pdf

190-KOL-2006-CORRESPONDENCE1.1.pdf

190-kol-2006-description (complete).pdf

190-kol-2006-drawings.pdf

190-kol-2006-examination report.pdf

190-KOL-2006-EXAMINATION REPORT1.1.pdf

190-kol-2006-form 1.pdf

190-KOL-2006-FORM 18.1.pdf

190-kol-2006-form 18.pdf

190-kol-2006-form 2.pdf

190-KOL-2006-FORM 3.1.pdf

190-kol-2006-form 3.pdf

190-KOL-2006-FORM-27.pdf

190-kol-2006-gpa.pdf

190-KOL-2006-GPA1.1.pdf

190-KOL-2006-GRANTED-ABSTRACT.pdf

190-KOL-2006-GRANTED-CLAIMS.pdf

190-KOL-2006-GRANTED-DESCRIPTION (COMPLETE).pdf

190-KOL-2006-GRANTED-DRAWINGS.pdf

190-KOL-2006-GRANTED-FORM 1.pdf

190-KOL-2006-GRANTED-FORM 2.pdf

190-KOL-2006-GRANTED-SPECIFICATION.pdf

190-kol-2006-reply to examination report.pdf

190-KOL-2006-REPLY TO EXAMINATION REPORT1.1.pdf

190-kol-2006-specification.pdf


Patent Number 250576
Indian Patent Application Number 190/KOL/2006
PG Journal Number 02/2012
Publication Date 13-Jan-2012
Grant Date 10-Jan-2012
Date of Filing 07-Mar-2006
Name of Patentee BHARAT HEAVY ELECTRICALS LIMITED
Applicant Address REGIONAL OPERATIONS DIVISION (ROD), PLOT NO: 9/1, DJBLOCK 3RD FLOOR, KARUNAMOYEE, SALT LAKE CITY, KOLKATA-700091, HAVING ITS REGISTERED OFFICE AT BHEL HOUSE, SIRI FORT, NEW DELHI-110049, INDIA
Inventors:
# Inventor's Name Inventor's Address
1 SYED TANWIRUL HASAN RIZVI BHARAT HEAVY ELECTRICALS LIMITED,(A GOVERMENT OF INDIA UNDER TAKING) HPEP-RAMACHANDRAPURAM, PROJECT ENGINEERING DIVISION, ADMINISTRATIVE BUILDING, HYDERABAD -502 032 ANDHRA PRADESH INDIA
2 MULINTI SIVA PRASAD BABU BHARAT HEAVY ELECTRICALS LIMITED,(A GOVERMENT OF INDIA UNDER TAKING) HPEP-RAMACHANDRAPURAM, PROJECT ENGINEERING DIVISION, ADMINISTRATIVE BUILDING, HYDERABAD -502 032 ANDHRA PRADESH INDIA
3 RAMAVAJJULA CHENGA VENKATA SUBRAHMANYA PRASAD BHARAT HEAVY ELECTRICALS LIMITED,(A GOVERMENT OF INDIA UNDER TAKING) HPEP-RAMACHANDRAPURAM, PROJECT ENGINEERING DIVISION, ADMINISTRATIVE BUILDING, HYDERABAD -502 032 ANDHRA PRADESH INDIA
PCT International Classification Number B01D 1/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA