An experimental study in using natural admixture as an alternative for chemic...
LPG – Liquefied Petroleum Gas & Gas Detection System
1. LPG – Liquefied Petroleum Gas
& Gas Detection System
– LPG & Gas Detection System,
Installation, Testing & Commissioning,
design, Calculation.
Prepared By: Monzer Salahdine
2. Introduction
LPG System used to supply :
LPG: Liquefied Petroleum Gas
I. Building – residential – kitchens.
II. Restaurants, industrial kitchens.
III. Laboratories, medical collages.
IV. Boilers.
V. Cars.
3. Introduction
LPG, Gas detection Systems:
I. LPG – Mechanical: Piping, Solenoid, Outlets.
II. Gas Detection System, Sensors, Panels.
LPG, Code and Standards:
1. NFPA 58: Liquefied Petroleum Gas Code.
4. Schematic Module
PIPES ASSETS
LPG & Gas Detection System as below procedure:
TESTING &
COMMISSIONING
MAINTENANCE
& OPERATION
MaintenanceInstallation & Commissioning
5. Introduction
What is LPG:
A - Liquefied petroleum gas or liquid petroleum gas (LPG or LP gas), also referred to as simply
propane or butane, is a flammable mixture of hydrocarbon gases used as a fuel in heating appliances,
cooking equipment, and vehicles.
B - Varieties of LPG bought and sold include mixes that are primarily propane (C3H8), primarily
butane (C4H10) and, most commonly, mixes including both propane and butane.
C - LPG has a typical specific calorific value of 46.1 MJ/kg compared with 42.5 MJ/kg for fuel oil and
43.5 MJ/kg for premium grade petrol (gasoline). However, its energy density per volume unit of 26
MJ/L is lower than either that of petrol or fuel oil, as its relative density is lower (about 0.5–0.58,
compared to 0.71–0.77 for gasoline).
6. Introduction
What is LPG:
D - As its boiling point is below room temperature, LPG will evaporate quickly at normal
temperatures and pressures and is usually supplied in pressurized steel vessels. They are typically filled
to 80–85% of their capacity to allow for thermal expansion of the contained liquid. The ratio between
the volumes of the vaporized gas and the liquefied gas varies depending on composition, pressure, and
temperature, but is typically around 250:1. The pressure at which LPG becomes liquid, called its vapor
pressure, likewise varies depending on composition and temperature; for example, it is approximately
220 kilopascals (32 psi) for pure butane at 20 °C (68 °F), and approximately 2,200 kilopascals (320 psi)
for pure propane at 55 °C (131 °F). LPG is heavier than air, unlike natural gas, and thus will flow
along floors and tend to settle in low spots, such as basements. There are two main dangers from this.
The first is a possible explosion if the mixture of LPG and air is within the explosive limits and there is
an ignition source. The second is suffocation due to LPG displacing air, causing a decrease in oxygen
concentration.
E - Commercially available LPG is currently derived from fossil fuels. Burning LPG releases carbon
dioxide, a greenhouse gas. The reaction also produces some carbon monoxide. LPG does, however,
release less CO, 2 per unit of energy than does coal or oil. It emits 81% of the CO
2 per kWh produced by oil, 70% of that of coal, and less than 50% of that emitted by coal-generated
electricity distributed via the grid. Being a mix of propane and butane, LPG emits less carbon per joule
than butane but more carbon per joule than propane.
7. Introduction
Odor Of LPG:
In their natural state, LPG (Propane and Butane) and Natural Gas
(Methane) are all odorless gases. The distinctive smell that people
associate with these gases is actually added to them as a safety
measure.
For many decades, the gaseous fuels industry has added odorants to
LPG and Natural Gas so that people can detect gas leaks with nothing
more than their noses. Without the addition of an odorant, leaking
gas could collect without being detected. This would create a
dangerous condition that could lead to an explosion or fire.
8. Introduction
LPG – schematic – residential example:
Gas Detector Of LPG at low level ( LPG heavier than
air).
Gas Detector Of Natural Gas and Coal gas at High
level (Air heavier than Natural Gas & Coal Gas).
10. Training Module
In case of gas leakage inside the area (Kitchen, Lab), the gas sensor will
be activated.
When sensor activated, it will send a signal to the control panel which
will treat it as leakage inside the lab.
The panel will give signal to the solenoid valve to close immediately
(safety issue) to make sure no more gas flow to the area.
The panel will give another signal to the siren light (alarm, mean there
is leakage).
The panel will give signal to fire alarm system which will deactivate the
main solenoid valve of LPG of entire building(safety issue).
The panel will give signal to BMS system to notify to the operator
(maintenance team) that there is a gas leakage.
The operator (maintenance team) has to check if there is leakage or any
of outlet open and to close it immediately.
When make sure that no more gas leakage inside the lab, the operator
to make reset for the panel which will activate the system and the gas
flow inside the lab, and to reset the solenoid manually.
In case of fire alarm in the building, the main solenoid will be shut off
(safety issue), once signal not disappear the system will be automatic ally.
11. Schematic Module
LPG Station
Main LPG panel, including solenoid and
regulator( up to 20 PSI) Solenoid Valve
SUB LPG Panel
Outlets
Including Solenoid
& Regulator( up to
5 PSI)
Liquid Gas
6.9 Bars
5 PSI
Outlets
1.5 to 2.5 PSI
10-20 PSI
13. Pipes
Pipes for LPG: black steel seamless SCH80, galvanized steel,
polyethylene (under ground) Or Copper Pipes Type K & L:
Black steel Pipes – seamless SCH 80, threaded
installed in double containment pipes for protection
or welding without double containment.
Copper Pipes Brazing and threaded for the fittings
( valves, Outlets).
14. Solenoid Valve
It is electrical control valve energized from
control panel to shut off the gas in case there is
leakage.
Solenoid valve is normally close, once the panel
energized the panel send signal to solenoid to
open.
In case there is leakage, the panel cut the power
to solenoid and became again closed ( solenoid
Spring Type).
15. Detector
Detectors for LPG SENSITROM brand or other.
Detectors installed at low level at 30 cm from finish floor level
and above ceiling in double containment or near the welding
joint,
Detector detect the LPG leakage and give signal to detection
control panel.
This sensor module utilizes an MQ-6 as the sensitive
component and has a protection resistor and an adjustable
resistor on board. The MQ-6 gas sensor is highly sensitive to
LPG, iso-butane, propane and less sensitive to alcohol,
cooking fume and cigarette smoke. It could be used in gas
leakage detecting equipment in family and industry. The
resistance of the sensitive component changes as the
concentration of the target gas changes.
Each detector will have an IP and address where all detectors
will be labeled and reflected the same label in LPG detection
panel- in case of leakage will knowing which detector giving
the signal and the location of each.
16. SIREN LIGHT
SIREN light for LPG SENSITROM
brand or other.
Once LPG system is activated, panel will
give signal to siren light to alert the area
about the LPG leakage( Visio and
Audio).
Wall mounted or ceiling mounted.
17. Detection Control Panel
Detection control panel for LPG SENSITROM brand or other.
When sensor level reach more than 10, alarm 1 will be activated( solenoid level
close but no alarm).
When sensor level reach more than 15, alarm 2 will be activated( solenoid
close, alarm occur).
Once sensor level reach more than 20 , alarm 3 will be activated ( solenoid
close, alarm occur, given alarm to fire alarm and BMS).
18. LPG Gas Panel
Ball Valve
Strainer
Solenoid Valve
Gas detector
Gas regulator
Pressure Gauge
Ball Valve
Gas Relief
19. Testing & Commissioning
The LPG system tested and certified by Third Party-
specialist in installation and commissioning of LPG system
and certified from NFPA58.
Below tools used for the tests:
20. Testing & Commissioning
Test Procedures:
The testing commissioning of LPG system follow the below
procedure:
1) Leak test( all pipes are tested by nitrogen for leak test).
2) Flushing( all pipes flushed by compressed air and nitrogen
to clean them from particles and humidity.
3) Cross test(valve test- when valve close, gases not allow to
reach to others connections.
4) Flow test.
5) Final leak test once open the LPG, testing by manual LPG
detector sensor.
21. Testing & Commissioning
Why we make the above test ??
Targets and goals of LPG tests:
1. To maintain the equipments life and saving
money.
2. To reduce the risk (avoid LPG leakages in
future).
3. Maintenance team to inspect and check in
daily basis to maintain the above two items
(check list).
22. Precautions & Recommendations
1. Once LPG detector detect a gas leakage,
system will be alert, all persons should leave
the room immediately.
2. Specialist of LPG system (maintenance
company) should investigate the cause of
leakage and rectify if any than to reset and re
open the LPG system.
3. Maintenance company to make a check list
for each panel in daily basis.
4. Damages pieces or sensors to be rectified
immediately to maintain secured areas.
25. Design & Calculation
Storage Calculation:
a.) Estimate No. of Lpg outlets
1. FOUR GAS BURNER RANGE ON GAS OVEN = 1 OUTLET
2. GAS POT STOVE ON STAND = 1 OUTLETS
3. SMOOTH PLATE GAS GRIDDLE = 0 OUTLET
4.GAS BIOLING PAN = 0 OUTLET
5. BOWEL GAS FRYER = 0 OUTLET
b.) Design Datas:
1. 4 BURNER OVEN = 65,000 Btu/Hr
2. GAS POT STOVE ON STAND = 40,000 Btu/Hr
3. SMOOTH PLATE GAS GRIDDLE = 30,000 Btu/Hr
4.GAS BIOLING PAN = 30,000 Btu/Hr
5. BOWEL GAS FRYER = 30,000 Btu/Hr
TOTAL = 105,000 Btu/Hr
c.) Calculation of Lpg consumption/day:
3. LPG HEATING VALUE AFTER VAPORIZATION = 2,500 Btu/h/Ft³ FROM ASPE
4. SIMULTANEOUS USE FACTOR ( PEAK HOUR AT LUNCH ONLY ) = 60%
5. ASSUMED BURNER WORKING TIME = 6 Hrs./Day
( 2 hrs per meal serve)
TOTAL LPG CONSUMPTION PER DAY = 151 Ft³
CONVERTING CU FT OF VAPOR TO GALLONS (75 ft3 / 36.39) = 4 G/Day
USE STORAGE TANK FOR ONE WEEK = 110 L
26. Design & Calculation
Pipe Size – Steel Pipe Sch40:
LPG pipes size depend to the
following:
- Pressure inside the pipe.
- Pipe lengths.
Btu/h or KW will be reduced with
pipe length ( otherwise pipe size to
be increased – see below).