How does a condensate return system work

In a pumped condensate return system, the flashing condensate is discharged into a vented tank, from which the flash steam is removed. The condensate must be pumped from the vented tank to the collecting tank, and then pumped from the collecting tank to the boiler.

What is a condensate return unit?

Condensate return units are designed to collect the returns and move the condensate along quickly and efficiently, minimizing heat loss and thus the energy required to heat it back to steam.

What is boiler condensate return?

Return Condensate to the Boiler. When steam transfers its heat in a manufacturing process, heat exchanger, or heating coil, it reverts to a liquid phase called condensate. An attractive method of improving your power plant’s energy efficiency is to increase the condensate return to the boiler.

Do I need a condensate return pump?

If the outlet pressure here can be greater than the inlet pressure, then you need a condensate pump system. … That is pressurized system. But the thing about any system is that we want to return the condensate as hot as possible.

How do you calculate condensate return?

  1. = (1 – Flash Steam Fraction) x (Condensate Load, lb/hr) x Annual Operating Hours x (Total Water Costs, $/gal)/ (Water Density, lb/gal)
  2. = (1 – 0.12) x 10,000 x 8,000 x $0.004 ÷ 8.34.
  3. = $33,760.

How do you calculate boiler makeup water?

Four gallons per hour per horsepower is the rule of thumb when calculating water used by a steam boiler, but 34.5 pounds of steam per hour per horsepower is more exact. These are both ways of determining how much make-up water goes into a steam boiler.

What does a condensate tank do?

Condensate tanks are part of a condensate return system, and are used to store all the condensate water returned from a steam system. … This reduces the amount of energy needed to transform water into steam and results in lower operating/utility costs.

How do you size a condensate return tank?

Condensate pumps are typically sized at three times (3x) normal condensing or evaporation rate. These guidelines are based upon design and operating experience. However, upon proper application, units can be sized at two times (2x) the condensing or evaporation rate. Enter the load.

How do Ogden pumps work?

The Spirax Ogden Automatic Pump delivers a known quantity of water at each stroke. Therefore by counting the strokes over a given period the pump can be used as a simple steam or condensate meter. A key is provided for resetting this counter to zero.

Can steam condensate go up?

Lifting condensate from a steam main It is sometimes necessary to lift condensate from a steam trap to a higher level condensate return line (Figure 14.5. 1). The condensate will rise up the lifting pipework when the steam pressure upstream of the trap is higher than the pressure downstream of the trap.

Article first time published on

What is the maximum recommended condensate return inlet temperature to a vacuum condensate for boiler feed pumping system?

Here are some typical conditions that may require a pump’s use to overcome instances of negative differential due to higher TDH/backpressure: Backpressure from lift created by an elevated collection tank. Piping friction caused by transporting condensate over distance. Pressurized Collection Tank or Flash Vessel.

How does a steam powered condensate pump work?

The goal is to pump hot condensate from low points in the building back to the boiler system as quickly as possible. The condensate flows by gravity from the steam traps down into the condensate receiver and the water/condensate level in the receiver rises. There is a float or mechanical alternator in the receiver.

What is condensate system?

The steam/condensate systems are an integral part of the water boiler system. The condensate system includes anywhere that the steam condenses to form liquid water. As the vapor leaves the low-pressure turbine it contains droplets of water.

What is condensate in a boiler?

Condensate is what gets produced when your boiler is being used to heat your home or produce hot water. … Once enough heat is produced from this vapour, it’s condensed back into water form. After this water has been collected, it gets expelled out the condensate pipe.

Why it is wise to return all the condensate back to the boiler room?

Condensate contains not only water, but also boiler treatment chemicals and the energy transferred during combustion. Condensate, therefore, needs to be returned to the boiler to: Improve energy efficiency. Reduce chemical cost.

What is the difference between steam and condensate?

Condensate is the liquid formed when steam passes from the vapor to the liquid state. In a heating process, condensate is the result of steam transferring a portion of its heat energy, known as latent heat, to the product, line, or equipment being heated.

Why condensate steam is recirculated to boiler?

At the end of a steam power cycle, the steam is condensed to water. A condensate pump recirculation water valve controls the bypass flow from the pump outlet back to the condenser, preventing overheating and cavitation in the pump. …

How much condensate does a boiler produce?

A general rule of thumb, 3.5 litres of condensate is produced for every 30kw of input providing the boiler is operating in full condensing mode. A boiler having 30kW of input operates for 1200 hours annually will produce approximately 4200 litres of condensate.

What is a condensate deaerator?

Deaerators are mechanical devices that remove dissolved gases from boiler feedwater. Deaeration protects the steam system from the effects of corrosive gases. … This in turn depends upon the ratio of boiler feedwater makeup to returned condensate and the operating pressure of the deaerator.

Do boilers use a lot of water?

Do boilers waste water or energy? No, they do not waste water because boilers are a sealed system. Modern boiler systems are just as efficient as any gas forced-air furnace.

What are the requirements of boiler feed water?

Working Pressure (Bar)75 – 100Dissolved oxygen (measured before oxygen scavenger addition)mg/l0.02 (Physical removal of dissolved oxygen)Total hardnessFrench degrees0.05Oily mattermg/l0.05

What is a cycle in a boiler?

A boiler cycle consists of a firing interval, a post-purge, an idle period, a pre- purge, and a return to firing. Boiler efficiency is the useful heat provided by the boiler divided by the energy input (useful heat plus losses) over the cycle duration.

Is a condensate pump the same as a sump pump?

Condensate pumps are nothing more than small sump pumps, designed to pump and lift water (via the smaller clear plastic tube coming from inside the “box”) from a central collection point to a remote location. This can be a floor drain, utility sink, standpipe in a drain pipe by a laundry area, or outside the house.

What happens when a condensate pump fails?

In newer homes, excess water from condensation goes right into a nearby floor drain. … So furnace installers mount a condensate pump right on the furnace and route the drain line to a far-off sink or floor drain. If that condenser pump fails, the water overflows the pump and spills onto the floor.

What is pumping trap?

Thermax Pump Trap is a condensate removing Pump. It removes condensate instantly in stall condition improving process effectiveness with the help of operating pressure of process.

How many pounds of steam does it take to lift a condensate?

This is almost as good as telekinesis. If you remember from high school physics, one pound of pressure will raise water 2.33 feet. Let us assume the condensate pipe is ten feet above the steam trap discharge. If you divide ten feet by 2.33, we would need 4.3 pounds of steam pressure.

How high will a steam trap lift condensate?

Steam Condensate Lift using an On-Off Control Scheme This is enough pressure to lift the condensate 12 feet to a gravity return main.

How do I stop my steam from Condensating?

Activate cold steam piping slowly at reduced pressure and with trap bleed valves continuously open. To prevent possible condensate accumulation, place blowdown valves before and after a vertical rise.

What are the benefits of recovering condensate?

  • Significant savings on energy costs.
  • High boiler feed water temperature minimises dissolved oxygen and therefore helps prevent corrosion.
  • Reduces the total dissolved solids (TDS) in the boiler feed water.
  • Minimises the need for makeup water and associated costs.

What is flash tank in boiler?

The function of a flash tank is to allow high-pressure condensate to flash and a reduced pressure steam. … It can also be used to reduce and cool to low-pressure steam before re-introducing it to the boiler or condensate receiver, or discharge directly from the system.

What causes steam to flash?

What causes Flash Steam? Flash steam occurs because the saturation point of water varies according to pressure. … To compensate for the excess amount of energy, part of the water molecules absorb the excess energy as latent heat and evaporate to form steam.

You Might Also Like