Why did the pH increase when boiler tube leakage occured?
pH doesnt increase anything. But a high pH reading indicates acidity while a low one indicates a base. A pH of about 6.5-7 is neutral (water).
The average lifespan of a boiler tube is 20 to 40 years. Boilertubes are made out of heat-resistant carbon and low-alloy steel.
in which the hit is around the water tube
By adding potash or bicab to the water.
due film boiling ,metal temperature riser tubes increase cases for rapture.
Water Tube Boilers Suitable for high steam pressure (above 500 psig) and temperature(to 1000 F) and large capacities exceeding millions of lb/h of steam. Extended surfaces ca…n be used in waste heat applications to make the boilers compact if the gas stream is clean. Various types of fuels can be fired with ease including solid,liquid and gaseous. The water cooled membrane wall construction makes an excellent furnace. If the gas stream is dirty(as in MSW applications)provision can be made for cleaning using soot blowers or rapping mechanisms.Wide spaced tubes can be used at the gas inlet to minimize bridging of slag deposits and tube spacing can be decreased as the gas is cooled.This flexibility does not exist in fire tube designs. Superheaters if used can be located at the optimum gas temperature region shielded by any number of screen tubes.In fire tube boiler the choice is at the gas inlet or exit. Due to low water volume,the startup time is lesser and response to load changes is faster compared to fire tube boilers. If the gas pressure is high,say above 5 psig,the shell/casing design gets complicated and expensive though it can be done. Due to higher heat transfer coefficients surface area required is lesser and hence gas pressure drop is also lower. For multiple pressure designs as in gas turbine exhaust applications,water tube is the only choice.
In a fire tube boiler, the water surrounds a set of tubes through which the fire and the products of combustion travel (as opposed to a water tube boiler, in which the wat…er travels through the tubes, and the fire surrounds the tubes). The HVAC Veteran
Baffles in water tube boilers are generally spiral twisted pieces of metal (though other methods have been used) inserted into the flue tube to cause turbulence, in addition t…o back pressure for better heat extraction. Typically, the design is to break the laminar flow in the exhaust gases and allow a better heat transfer through the tube. This will lower stack temperature and increase over all thermal efficiencies in water tube boilers.
the pH value in boiler feed water is 9.2
This is caused by overheating of the shell plates and it affecstheentire thickness of the plate. So, too much heat = weaker metal =thus bulge due to the weakend metal succombi…ng to the boilerpressure. This is often due to deposit on the WATER side of tube.THe METAL gets too hot, thus the metal is weaker and bulges due tothe pressure found inside the piping.. NOT the water gets too got.This is important to distinguish from a blister which is caused bya slag inclusion forming a lamination at the time the plate wasrolled in the steel mill. Thus a blister is defect in the metal.Blisters may also be caused by a hydrogen environment. Blistersalso are worsened by deposites which cause them to crack andrelease scale. This process repeats until it bursts. The bugleformation is similar in that it actually breaks away the scale thatformed it upon its formation. This will allow water to absorb heatproperly from the metal again and delay the progression of thebulge until the scale reforms. Small Bulges can be left in place ifscale forming processes are removed. Blisters should be replacedeventually as they are thinner then is normally permitted by code.
November 12, 1944 , the first basic patent for Corner Tube Boilers (= Eckrohrkessel, Berlin, Germany) was applied for. During this time oil as fuel ran short. All efforts, to …save energy and use domestic and alternate resources, were to be made. One came up with an idea, to operate cars and trucks, not on gasoline or diesel fuel, but with steam. Dr. Vorkauf , a specialist for water circulation in boilers, especially in La Mont boilers (forced circulation boilers), got the order to design a small boiler for a steam engine fired with coal or wood. The result was not as expected a forced circulation boiler, but a natural circulation boiler. A forced circulation boiler of this size would have been too costly. Due to his experience with the La Mont boiler Dr. Vorkauf had the idea to obtain a pre-separation of the steam - water mixture in front of the drum. An extremely lively water circulation resulted from unheated downcomers and a suitable arrangement of the mixture tubes. The unheated downcomers were installed in the 4 corners of the boiler, where they not only served the purpose of water circulation, but also as a support frame for the boiler. The boiler with such an arrangement of the downcomers in the corners was called Corner Tube Boiler (Eckrohrkessel, Eckrohr-Boiler) .
we can increase boiler efficiency by recovering the heat which is being carried by flue gases.by incorporating different things like Economizer, Air pre-heater , Super-heater …and feed-water heater, we can there ll be notable increase in efficiency of boiler.
Well I'm not hundred percent sure of that but as long as I am aware it should remain a '7' because it's still neutral meaning pure water just heated up a little and if it does… happen to change then I believe it would be a 8 ranging towards basic not acidic.