Condensate Pump System
STEAM POWERED CONDENSATE RETURN UNIT
The condensate from the process flows in the tank by sending the air in the tank out through the solenoid valve located in the discharge line. The tank is equipped with the Atech LCS100 compact on-off level control system. When the water level reaches the upper electrode tip the solenoid valve in the vent line is closed and simultaneously the solenoid valve in the booster-steam line is opened. The steam that fills the tank pushes the condensate to the main condensate tank. When The condensate level decreases and the lower electrode tip emerges, the solenoid valve in the booster-steam line is closed and the solenoid valve in the vent line opened. The cycle repeats itself.
Before entering the condensate-return unit the condensate is must be collected in a condensate header. This condensate header should be equipped with a vent. There should be check valves to prevent reverse flow and manual shut-off valves at the inlet and outlet points of the condensate tank. There should be a manometer on the tank, solenoid valves on the booster steam and vent lines, and a ball float steam trap between the booster steam line and the condensate header. As the condensate return unit operates without a float, it is not affected by problems such as water hammer and staying stuck.
CALCULATION
For example; Let's assume that the amount of condensate thrown out in the area where you intend to return the condensate with the condensate pump is 3 t/h. If the condensate had been collected in the condensate tank, it would have returned to the boiler at approximately 80⁰C with heat losses, but since it was thrown out, approximately 10⁰C feed water will be given to the boiler instead of the condensate.
In this case, the energy thrown out together with the condensate is:
Q = m.c.Δt → Q= 3000.1.70 = 210.000 kcal/h
Natural gas lower heating value = 8250 N kcal/m3
Natural Gas Price= 5 tl/m³
Consequently,
Amount of Natural Gas Spent Extra = (210.000 kcal/h / 8250 N kcal/m³) = 25.45 m3/h
Amount = 25.45 m³/h x 6.3 TL/m³ = 160.34 TL/h = 3848 TL/day
In this case, it is seen that a steam powered condensate return unit that you will install in your facility will pay for itself in less than 1 month, even if only natural gas loss is considered. In addition, considering that it will continue its duty for many years, it should be taken into account that it will provide high savings. While calculating the above fuel cost, the calculation was continued by assuming that the combustion process of the fuel was realized with 100% efficiency. However, it should never be forgotten that a process can never operate with 100% efficiency., These long and very important expenses such as boiler, burner operating above the required capacity, related pumps and motors, steam lines and other armatures' wear and depreciation, water preparation (circulation, treatment, heating...), electricity, labor, worker side expenses are examples of secondary losses.