FIELD OF THE INVENTION
This invention relates generally to burner viewing systems. More particularly,
the invention relates to a system to continuously monitor the profile of
refractory opening near oil burner in circulating fluidized bed combustion
(CFBC) boilers to identify parametric causes of clinker formation for taking
corrective measures.
BACKGROUND OF THE INVENTION
In the prior arts of burner viewing system for CFBC boilers, view ports are
provided on the opposite side wall of the oil burner which enable the operator
to view the oil burner flame only when the burner is in service. With the
known burner viewing systems in CFBC boilers, it is not possible to cull out
the causes for the clinker formation. Clinker formation in the refractory
opening near oil burners in the CFBC boilers is hazardous and hence leads to
unwanted plant outages. As of now, there is no means to monitor
continuously the profile of refractory opening near the oil burner in the CFBC
boilers. Accordingly, there is a need to propose a system to identify the time
and parametric causes for clinker occurrence for taking corrective measures
to nullify the clinker formation near the oil burner in CFBC boilers.
OBJECTS OF THE INVENTION
It is therefore an object of the present invention to propose a system to
continuously monitor the profile of refractory opening near oil burner in
circulating fluidized bed combustion (CFBC) boilers to identify parametric
causes of clinker formation for taking corrective measures.

Another object of the present invention is to propose a system to
continuously monitor the profile of refractory opening near oil burner in
circulating fluidized bed combustion (CFBC) boilers to identify parametric
causes of clinker formation for taking corrective measures, in which means
are provided to view/record the operating parameters with reference to time.
A further object of the present invention is to propose a system to
continuously monitor the profile of refractory opening near oil burner in
circulating fluidized bed combustion (CFBC) boilers to identify parametric
causes of clinker formation for taking corrective measures, which provides
the data for ascertaining the causes for clinker formation on the refractory
near oil burner.
SUMMARY OF THE INVENTION
Accordingly, there is provided a system to continuously monitor the profile of
refractory opening near oil burner in circulating fluidized bed combustion
(CFBC) boilers to identify parametric causes of clinker formation for taking
corrective measures. According to the invention, means is installed in the
burner mounting seal box of CFBC boilers with an objective to monitor
dynamically the profile of refractory opening near oil burner in CFBC boilers.
The methodology broadly includes an optical system, image transfer
assembly, monitoring assembly and a software program to be included in the
existing BMS-PLC.

The optical system primarily consists of a set of lenses arranged so as to
provide the image of the refractory opening to the image transfer assembly.
The image transfer assembly comprises reflective surfaces oriented according
to the monitoring assembly so as to visualize the refractory opening profile in-
situ as well as the image in the reflective plates to be captured and
transferred as digital signal to the BMS-PLC by a Charge Coupled Device
(CCD). The software program to be included in the BMS-PLC is developed to
allow processing of the digital signals obtained through a viewer assembly for
further processing and analysis. The methodology has been designed to make
the vulnerable components maintainable.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
FIG. 1 : System of present invention to monitor the refractory opening near
oil burner in CFBC boilers.
FIG. 2 : Burner throat pipe according to the system of present invention.
FIG.3 : Optical system according to the system of the invention.
FIG. 4 : Viewer assembly according to the system of the invention
DETAILED DESCRIPTION OF THE INVENTION
According to the present invention and as shown in Figure-1, the system
comprises a plurality of burner throat pipe (4) to accommodate a plurality of
optical system (5) with an viewing angle 02 in the range of 45 to 55 Deg; a
plurality of viewer assembly (6) having a provision for circulating cooling air
and to mount a signal module (7); a seal box (2)

designed to support the burner throat pipe (4) as well as to contain
considerable volume of cold air; an oil burner (1) is mounted on the seal box
(2) whose spray angle is 9i in the range of 55 to 75 Deg, inside of the seal
box (2) refractory (3) is filled in, and the optical system (5) is oriented to view
the bottom portion of the refractory opening, wherein the profile of the
refractory opening is viewed through the optical system (5) and its image is
transferred to the viewer assembly (6), wherein the optical image made
available in the viewer assembly (6) is converted into digital signal using .said
signal module (7); a BMS-PLC system, having a software program receiving
the digital signal for continuous on-screen monitoring of the refractory profile
including storing of the operating parameters, wherein the PLC having data
retrieval facility so as to correlate the refractory profile, time reference and
the operating parameters, and wherein an analysis of the processed data
enable identification of the cause for the clinker formation at various stages.
The burner throat pipe (4) as shown in Figure - 2, has a pipe (8) with
counter flanges (11) to mount the burner (1). Inside the pipe (8), there is
provided a housing pipe (9) having an opening and a stub (10) welded to it.
The optical system (5) envisaged for the invention, as shown in Figure-3, has
a quartz glass (12), a set of lenses (13, 14), housed inside a casing pipe (15).
The set of lenses (13,14) and the quartz glass (12) are located inside the
casing pipe (15) using a plurality of retainers (16,17,18,19,20). The retainer
(19) is designed to provide a passage for cooling air. The connection of the
retainer (20) and the casing pipe (15) helps in fixing the set of lenses (13,14)
and the quartz glass (12) firmly.

A guiding pin (21) helps to mount the retainer (19) in the pre-determined
position ensuring the flow of cooling air to form an air curtain, which helps in
cleaning as well as cooling the quartz glass (12). An image plate (23) is
mounted on a fixing tube (22). The image plate (23) is so arranged to have
the image through the set of lenses (13, 14). A plurality of mounting flanges
(24, 25) are provided with locating holes and welded to the fixing tube (22).
The locating holes in the mounting flanges (24, 25) help in positioning the
image plate (23) in a pre-determined position.
As shown in Figure-4, the viewer assembly (6) has a housing (26), wherein
an image plate (29) is positioned with the help of a support base (28), a
retainer (30) and a guide pin (31). The housing (26) is provided with a
cooling air stub (27). A set of flanges (32) are welded to the housing (26).
The locating holes in flanges (32) and the guide pin (31) help in fixing the
image plate (29) in a pre-determined position. The image of the refractory
opening can be viewed through a viewing glass (33) provided in the housing
(26). A signal module (34), can be mounted on the housing (26) for
converting the optical image into digital signal and making the digital signal
available at BMS-PLC. By suitably including a program in BMS-PLC logics,
required parameters on the clinker formation can be obtained and analyzed.

WE CLAIM :
1. A system to continuously monitor the profile of refractory opening near oil
burner in circulating fluidized bed combustion (CFBC) boilers to identify
parametric causes of clinker formation for taking corrective measures,
comprising :
the system comprises a plurality of burner throat pipe (4) to
accommodate a plurality of optical system (5) with an viewing angle θ2 in
the range of 45 to 55 Deg; a plurality of viewer assembly (6) having a
provision for circulating cooling air and to mount a signal module (7); a
seal box (2) designed to support the burner throat pipe (4) as well as to
contain considerable volume of cold air; an oil burner (1) is mounted on
the seal box (2) whose spray angle is θ1 in the range of 55 to 75 Deg,
inside of the seal box (2) refractory (3) is filled in, and the optical system
(5) is oriented to view the bottom portion of the refractory opening,
wherein the profile of the refractory opening is viewed through the optical
system (5) and its image is transferred to the viewer assembly (6),
wherein the optical image made available in the viewer assembly (6) is
converted into digital signal using said signal module (7); a BMS-PLC
system, having a software program receiving the digital signal for
continuous on-screen monitoring of the refractory profile including storing
of the operating parameters, wherein the PLC having data retrieval facility
so as to correlate the refractory profile, time reference and the operating
parameters, and wherein an analysis of the processed data enable
identification of the cause for the clinker formation at various stages.

2. The system as claimed in claim 1, wherein the burner throat pipe (4)
comprises a pipe (8) with counter flanges (11) to mount on the burner
(1), and wherein the inside of said pipe (8) is provided with a housing (9)
having an opening with a stub (10) welded.
3. The system as claimed in claim 1, wherein the optical system (5)
comprises a quartz glass (12), a set of lenses (13,14) housed inside a
casing pipe (15) by means of a plurality of retainers (16-20), and wherein
a first image plate (23) for capturing the images of the refractory profile
and a retainer ring (9) through the lenses (13,14) is mounted on a fixing
tube (22).
4. The system as claimed in claim 1, wherein the viewer assembly (6)
comprises a housing (26) accommodating a second image plate (29) and
having a viewing glass (33), and wherein a signal module (34) is mounted
on the housing for converting the optical images to digital signals which
are transmitted to the BMS-PLC.
5. The system as claimed in claim 3, wherein the image plate (23) is made of
SS 304 with #8 mirror finish and is inclined to 45 Deg.
6. The system as claimed in claim 3, wherein the retainer ring (19) is
designed to provide air to cool the optics and form an air curtain to keep
the optics clean.
7. The system as claimed in claim 4, wherein the viewer assembly, has a
cooling air stub (27) welded.

8. The system as claimed in claim 1, wherein the BMS-PLC has a software
program built-in to store the image of refractory profile and operating
parameters with reference to time.

ABSTRACT

The invention relates to a system to continuously monitor the profile of
refractory opening near oil burner in circulating fluidized bed combustion
(CFBC) boilers to identify parametric causes of clinker formation for taking
corrective measures, comprising : the system comprises a plurality of burner
throat pipe (4) to accommodate a plurality of optical system (5) with an
viewing angle θ2 in the range of 45 to 55 Deg; a plurality of viewer assembly
(6) having a provision for circulating cooling air and to mount a signal
module (7); a seal box (2) designed to support the burner throat pipe (4) as
well as to contain considerable volume of cold air; an oil burner (1) is
mounted on the seal box (2) whose spray angle is θ1 in the range of 55 to 75
Deg, inside of the seal box (2) refractory (3) is filled in, and the optical
system (5) is oriented to view the bottom portion of the refractory opening,
wherein the profile of the refractory opening is viewed through the optical
system (5) and its image is transferred to the viewer assembly (6), wherein
the optical image made available in the viewer assembly (6) is converted into
digital signal using said signal module (7); a BMS-PLC system, having a.
software program receiving the digital signal for continuous on-screen
monitoring of the refractory profile including storing of the operating
parameters, wherein the PLC having data retrieval facility so as to correlate
the refractory profile, time reference and the operating parameters, and
wherein an analysis of the processed data enable identification of the cause
for the clinker formation at various stages.