Category: Marine Tech

INCINERATOR AND ITS USE ONBOARD
The Incinerator is designed according to the basic principles of ensuring a highly efficient combustion and a high degree of safety. It is a MARPOL equipment and is used to burn sludge/ waste oil and garbage onboard. 
The incinerator is designed with a primary combustion chamber for burning W.O oil and solid waste, and a secondary combustion chamber and an after-burning chamber for burning un-combusted exhaust gases.
The combustion chambers are equipped with diesel oil burners, called primary burner and secondary burner respectively.
The inner sluice door is automatically operated.

PRIMARY COMBUSTION CHAMBER
The incinerator is designed to combust solid waste and W.O oil. The heat from the primary burner will start burning the solid waste and the burner flame ignites the W.O oil. The very large heat transmission area in the combustion chamber optimizes the drying and burning of the solid waste.

SECONDARY COMBUSTION CHAMBER
The primary and secondary chamber are separated by a wall made of ceramic heavy duty refractory. In the secondary combustion chamber and after-burning chamber, any gases or particles not completely burned from the primary combustion chamber will be combusted definitively. 

COMPONENTS OF AN INCINERATOR:
1. Charging Door
2. Combustion Chamber
3. Afterburning Chamber
4. Second After burning Chamber     
5. Oil Burner with Built In Pump
6. Ash Cleaning Door
7. Air blower
8. Induced Draught Air Ejector
9. Damper
10. W.O burner
11. Double Wall for Air Cooling

12. Air Inlet nozzle
13. W.O supply tank
14. Mill pump15. Compressed Air
16. W.O Dosing Pump
17. Heating Element

18. Diesel Oil tank
19. Sluice

CONNECTIONS

a. W.O Oil Inlet

b. Steam Inlet
c. Steam Outlet
d. W.O Oil Ventilation Outlet
e. Diesel Oil Inlet
f. Diesel Oil Ventilation Outlet
g. Compressed Air Inlet
h. Electric Power Supply
i. Flue gas outlet
j. Drain W.O tank

k. Drain Diesel oil tank
l. – – –  yard pipe connection

The incinerator is designed to incinerate solid waste and all types of combustible non-explosive oil W.O with a flash point of min. 60°C, without being a nuisance to the surroundings. The incinerator is made as a compact plant of the multi-chamber design.
The incinerator is delivered with the following built-on main components:
– Air blower, supplying air for the induced draught air ejector, cooling air and combustion air.
– W.O burner
– W.O. dosing pump
– Primary D.O. burner for primary combustion chamber
– Secondary D.O. burner for secondary combustion chamber
– Control panel (CP1)
– Thermocouples for detecting primary and secondary combustion chamber temperatures and registering high temperature alarm
– Internal electric-cable, oil, air pipes and valves are factory installed
– Automatic built-on non-fire back sluice
– Supplied loose for installation in funnel:
– Thermocouple for detecting high flue gas temperature and alarm

PREPARATION FOR START-UP OF THE INCINERATOR
Before start-up of the incinerator, the following is to be carried out :
1. Open all inlet and outlet valves for diesel oil.
2. Open all inlet and outlet valves for waste oil and air.
3. Make sure that there are no hindrances for air admission to primary blower as well as
flue gas outlet.

START-UP OF THE INCINERATOR OP PROGRAM 'SOLID WASTE'
1. Make sure that the switch is turned to 'waste oil off'.
2. Activate the main switch on the control panel.
3. Reset the alarm lamps on the push button 'reset alarm'
4. Make sure that all the lamps are alight by pressing the button 'lamp test'
5. For starting of the incinerator, activate the switch for 'incinerator-start'
6. The incinerator will now start automatically by activating the secondary burner in the secondary combustion
chamber.
7. The secondary combustion chamber will have a temperature of 650℃, and the primary burner in the primary
combustion chamber will be activated. The incinerator the operate within set temperatures.
8. If the flame in the incinerator goes out, the incinerator is to be reset by means of "reset flame failure
primary and secondary burner"
9. If add solid waste to the primary combustion chamber using the sluice by activating the pushbutton on the
incinerator wall. 

START-UP OF THE INCINERATOR ON PROGRAM 'W. O'
1. Make sure that switch is turned to 'W.O on'
2. Before start-up of the incinerator, follow the incinerator given under point 'A', item 2 to 7.
When the temperature of the secondary combustion chamber is 650℃ the primary D.O burner in the primary
combustion chamber will be activated. After a preheating period of 25 seconds the W.O burner starts
automatically and operates within the set points.
(Please see the instruction manual).
When the 'delay burner' is switched to automatic 'AUT', the primary D.O burner operates for 25 seconds to
ignite the W.O burner automatically.
When the 'delay burner' is switched to manual 'MAN' the primary D.O burner operates all the time together
with the W.O burner.

ADDING OF SOLID WASTE
Before adding a new charge of solid waste, control whether the incinerator is ready to receive more waste or
not, by looking through the sight glass.

STOPING OF INCINERATOR
1. Activate the switch 'incinerator stop'
2. When the temperature in the incinerator drops to below 100℃, the incinerator stops automatically.
3. When the incinerator has stopped, switch off the main switch on control panel after the blower has been off for 30 minutes.

Q. What are the maintenance to be carried out in boiler?
Ans : Boiler maintenance: The boiler maintenance should always be executed with skill and in accordance with valid rules and regulations from the authorities. Below some recommendations are given for periodical inspections and maintenance.
Daily operation : Daily normal operation of the boiler, some work and check procedures have to be considered every day.
Step A: Check the boiler steam pressure and the water level.
Step B: Check that the feed water control system is operational see separate instructions.
Step C: Check the boiler water condition and inquire necessary countermeasures with regard to the feed and boiler water treatment. If necessary, blow-down the boiler.
Step D: Check the function of the oil burner at different capacities through the inspection holes on the boiler.
Step E:  Check the flue gas temperature after and or the draft loss across the boiler. If either the temperature or the draft loss is too high the smoke tube section, for the oil fired as well as the exhaust gas part, must be cleaned.

Q. What are the weekly checks?
Ans : Weekly routine checks
Step A:  Drain each water level glass for about 10-15 seconds.In case of contaminated boiler water sufficient water treatment the draining of the water level glasses must be done more often.
Step B: Check the safety water level device.
Step C:  Depending on the boiler water tests, blow-down the boiler. Open the blowdown valves quickly for a few seconds, and then close and open for about 5-10 seconds. Repeat this operation when required according to the boiler water tests.
Step D:  Perform scum blow out by means of the scum valve when required. The scum blow out must be carried out until the drained water is clean.

Q. What are the monthly routines?
Ans : Monthly routine checks
Step A:  Test all stand-by pumps.
Step B:  Check all boiler mountings for damage or leaks and repair & replace if necessary. 
Incorrect feed water treatment is commonly causing hard deposits or corrosion. Insufficient blow-down will cause sludge deposits in the tubes and accumulation of sludge in the bottom of the boiler. If hard deposits are not removed.it may lead to overheating in the boiler plate material, which is exposed to the flame in the furnace wall area. This may cause material damages. Incorrect feed water- treatment does not always lead to hard deposits. For example, a too low or too high pH-value may give an electrolytic reaction causing corrosion in the boiler. When the boiler interior is inspected, examine all parts carefully and be attentive to deposits, corrosion, and cracks. It is advisable to pay special attention to this inspection.

Q. What are the procedure and remarks for Boiler inspection?
Ans : Procedure and remarks for Boiler inspection
Step A:  Shut off the boiler and allow it to cool (below 100 deg C).
Note: The boiler should NOT be depressurised by lifting the safety valves and then filled with cold feed water as the stress induced by too rapid cooling may cause damage.
Step B: Empty the boiler and close all valves. If the boiler is connected to a second boiler, check that the valves between them are closed.
Step C:  Unscrew and remove the manhole hatch(es) on the boiler and enter the boiler when it is sufficiently cold. Check the welding in the boiler. A careful examination should be carried out with respect to any possible corrosion or crack formation. Special care should be taken to the water line area in the pressure vessel where oxygen pitting may occur. lf deposits are forming in the boiler tubes, the boiler should be chemically cleaned.it is advisable to consult a company of cleaning specialists rho will examine the boiler deposits and treat the boiler accordingly.
Note: After chemical treatment the boiler should be blown-down at Least twice a day for approximately one week. This will ensure that excessive sludge deposits due to chemical treatment do not collect in the bottom of the pressure vessel.
Contamination If the boiler is contaminated with foreign substances like oil, chemicals corrosion products etc, it is very important to act immediately to avoid damage to the boiler.
Step C:  Check the function of the high steam pressure switch by lowering the set point or by raising the steam pressure, e.g  by closing the main steam valve slowly. The burner must stop automatically.

Inspection of the boiler
A. Inspection of furnace: The furnace should be inspected at least twice a 3 year. During this inspection, the following issues should be taken into consideration: Check for cracks at the refractory    and that the furnace walls are free from excessive soot deposits. Examine carefully the area opposite the burner. Too much soot deposits indicate that the burner should be adjusted. Check that the smoke and stay tubes are intact and that soot deposits are within normal limits.

B. Inspection of exhaust gas section: The exhaust gas section should be inspected at least twice a year. During this inspection, the following issues should be taken into consideration: Check the welding in the exhaust section. A careful examination should be carried out with respect to any possible corrosion or crack formation. Check that the inlet box and outlet box are intact and that soot deposits are within normal limits. Check that the smoke tubes and stay tubes are intact and that soot deposit are within normal limits.

C.Inspection of boiler water side 
The boiler water side (interior) must be carefully inspected at least twice a year. This inspection is of great importance and no doubt the most important of all the maintenance measures. Since it   has a direct influence on the boiler longevity and on the security. At these inspections, hard deposits, corrosion, and circulation disturbances can be found at an early stage, and preventive measures must be taken to avoid unexpected material damage and boiler break down. The presence of hard deposits at the furnace wall and the smoke tubes reduces their heat transfer properties and decreases, the capacity of the boiler. Further, it can be established whether the feed water treatment is satisfactory and whether the blow down is carried out sufficiently.
Layers of thin oil film are exposed to the heating surfaces cause a bad heat transfer in the boiler, leading to overheating followed by burned out pressure parts, In order to remove such contamination a boiling out or acid cleaning are performed immediately.
Note: Corrosion products from the pipe system or insufficient boiler water treatment may result in corrosion in the boiler itself. It is therefore important to observe that such circumstances do not occur in the system.

Here Are The Piston Rings Questions And Answers Which Will Help You To Understand So Many Things

Question: What Is A Piston Ring And Why It Is Used?
Answer: A Piston Ring Is A Cast Iron Compression Ring, Fitted In The Piston Groove Such That These Rings Provide A Packing/seal Between The Piston And Liner. The Purposes Of Fitting Piston Rings Are:
1. They Do Not Allow The Hot Combustion Gases To Escape Towards The Scavenge Space.
2. They Transmit The Heat Taken By The Piston During The Entire Cycle Mainly Combustion Period To The Liner Walls.
3. They Help To Maintain The Cylinder Lub Oil Film Between Piston And Liner, Thus Carrying Out Boundary Lubrication With Point To Point Metal Contact. Cylinder L.O. Is Being Injected In The Upward Motion Of The Piston, Between 1st And 2nd Piston Ring And A L.O. Film Is Created Due To The Smearing Of Oil Due To Movement Of Piston Rings With Piston.

Q. How Many Piston Rings Are Used And What Are Their Types?
Ans: Generally 3-4 Piston Rings Are Used In One Piston. The First Ring Is A Controlled Pressure Relief Ring, It Is Thicker With Respect To Other Rings And Has A S- Type Of Groove, The Purpose Of CPR Is To Take The Most Of The Heat Induced On The Piston Crown, Thus Reducing The Amount Of Heat To Which The 1st Compression Ring Is Subjected. Thereby, Increase In The Life Of Compression Rings. Then There Are 2-3 Compression Rings Below It, The Basic Difference Is In Their Cuts, These Are Opposite As We Proceed Down. If The First Ring Is Right Hand Cut Second Will Be Left Hand Cut, It Is To Minimize The Escape Of Combustion Gases Through Them.

Q. What Do You Mean By Piston Ring Butt Clearance, How Is It Measured Onboard And Its Importance?
Ans: Piston Ring Butt Clearance Is The Cut That Is Made In The Ring Such That Due To Thermal Expansion The Ring Doesn't Collapse. Secondly, This Cut Makes It Possible To Fix And Remove Them. The Method Of Measuring Butt Clearance Onboard Is Paper-impression Method. When Liner Is Taken Out For Overhaul , A Piston Ring Is Inserted From Bottom Of The Liner And A Paper Is Placed On The Butt, An Impression Appears On The Paper Due To Oily Surface. This Paper Is Then Taken Out And The Clearance Is Measured By The Help Of A Vernier Caliper. It Should Be Around 0.5% Of The Liner Bore Diameter. If It Exceeds That Piston Ring Is Changed. However, It A General Practice To Change Piston Rings During Every Liner Or Piston Overhaul. 
Importance Of Butt Clearance: 
1. If All The Butts Get Aligned, The Combustion Gases Blow-by Or Blow Past Takes Place Which Might Lead To Scavenge Fire. 
2. If The Butt Clearances Of Any Piston Ring Decrease, The Ring Might Collapse And Not Seal The Gases.

Q. What Are An Oil Control Ring Or Oil Scraper Ring And Its Purpose? 
Ans: An Oil Control Ring Is A Type Of Piston Ring Used In Trunk Type Engine Which Nowadays Are Used As Auxiliary Engines. These Oil Control Rings Are Fitted In The Piston Skirt, In A Ring Groove Which Has Holes Through The Piston. The L.O. From The Sump Which Travels Up Through Gudgeon Pin For Piston Cooling, Goes Into The Groove While The Piston Is In Upward Travel And Is Smeared Into The Liner Surface. While Travelling Downward, The Oil Control Ring Scraps Down The L.O. From Liner Surface And It Is Sent Back To L.O. Sump. This Is Why It Is Also Known As Oil Scraper Ring.

Q. What Are The Main Reasons For Piston Ring Breabreakage?
Ans: 
1.    Piston Ring Breaks Due To Collapse Of The Ring Which Can Be Due To High Wear Of Rings High Liner Wear, Loss Of Lubrication Film. 
2.    Over Lubrication Can Also Lead To The Ring Breakage, By Hindering The Rings To Move Freely And Causing Fatigue Cracks. 
3.    Too Low Lubrication Feed Rate Can Cause Deposits Build Up Due To Absence Of Detergency Effect Of Cylinder Oil. It Can Lead To Loss Of Lubrication Film Resulting In Blow By And Collapse Of The Ring. Improper Running In After Renewal Of Piston Ring. 
4.    Uneven Wear Pattern Of The Liner Can Cause Excessive Stresses On The Rings Which May Led To Breakage. 
5.    Excessive Ovality, Clover Leafing And Formation Of Wear Ridges On The Running Surfaces Can Also Cause Piston Ring Breakage. 
6.    Worn Or Damage Piston Grooves And Improper Piston Ring Clearance. 
7.    Excessive Combustion Pressure Can Cause Over Stress To The Piston Rings. 
8.    Faulty Injector Or Improper Fuel Temperature Can Cause Incomplete Combustion And Excessive Deposits Which May Lead To Collapse Of Piston Ring. 
9.    Over Expansion Of Rings During Fitting. Use Standard Tools For The Fitting Of Piston Rings As Per The Manufacturer Recommendation. 
10.    Improper Piston Ring Design Or Inadequate Material. Use Rings As Recommended By Maker.