What is carryover in boiler?
Carryover also known as priming is any solid, liquid or vaporous contaminant that leaves a boiler with the steam. In low/medium pressure boilers (<100 bar) entrained boiler water is the most common cause of steam contamination. Foaming tendencies are increased with increases in alkalinity and solids content.
What causes boiler carry-over?
Mechanical causes of carryover include boiler design, high water level, firing method, and load characteristics. Chemical causes of carryover include high solids concentration (dissolved or suspended), excessive alkalinity, grease, oil, or other contamination.
What is carryover process?
Boiler water carry-over is the contamination of the steam with boiler-water solids. Bubbles or froth actually build up on the surface of the boiler water and pass out with the steam. This is called foaming and it is caused by high concentration of any solids in the boiler water.
What is carry-over in chemistry?
A process by which materials are carried into a reaction mixture to which they do not belong. In such cases, carry-over means the transfer of material (specimen or reagents) from one container, or from one reaction mixture, to another one.
What kind of damage can be caused by water carry over of the boiler?
Losses of 5% in turbine efficiency and 20% in turbine capacity have occurred due to deposition. When large slugs of boiler water carry over with steam, the resulting thermal and mechanical shock can cause severe damage. Loss of production may result from reduced capacity or equipment failure caused by carryover.
What is the effect of high conductivity in boiler?
When this occurs, the boiler becomes less efficient and increases the fuel consumption of the unit. High conductivity levels also heighten the risk that the boiler water becomes contaminated, which can be very dangerous.
What is carry over coefficient?
The carry-over coefficient represents the effectiveness of each cavity to dissipate the kinetic energy entering the cavity and has an effect upon the value of the discharge coefficient for the constriction following that cavity.
How do you calculate carry over?
Percent carryover can be calculated by subtracting the value of the first sample from the value of the third sample, dividing by the first sample value, and multiplying by 100.
How can we prevent carryover?
“When analyzing ionic samples, a wash solution containing counterions provides effective adsorption suppression. When analyzing hydrophobic samples, using an organic solvent as the needle wash solution can reduce carryover because it acts to solubilize and wash away the adsorbed sample components.
What are boiler troubles?
Boiler troubles: Sludge, scale, priming and foaming, caustic embrittlement, boiler corrosion are collectively known as boiler troubles. A. Caustic Embrittlement: (Inter crystalline cracking of boiler metal) It is the intercrystalline cracking of boiler due to Na2CO3.
How can reduce TDS?
Ways to Reduce or Remove TDS in Water
- Reverse Osmosis (R.O.) Reverse Osmosis removes TDS by forcing the water, under pressure, through a synthetic membrane.
- Distillation. The process involves boiling water to produce water vapor.
- Deionisation (DI)