Process heat and waste heat recovery with shell and tube units
Using heat that a process produces anyway a second time can reduce the additional energy demand - and in many plants steam carries heat to where it is needed. Shell and tube heat exchangers are an obvious design for both.
Heating with saturated steam
Where steam is available, it heats water or glycol circuits with particular density of duty: in condensing it releases its enthalpy of vaporisation - many times what the same kilogram of water could deliver over a usual temperature spread. That is why steam applications manage with small quantities of steam.
Arithmetically the case differs from a pure liquid duty: while the steam condenses, the steam side has no temperature spread in the usual sense, and its heat transfer depends on the condensate film rather than on the mass flow. Our calculation core holds a dedicated correlation for this; details are in the guide heating with saturated steam.
Recovering heat from process water
Warm process water or effluent carries energy out of the building that can be tapped beforehand - to preheat fresh water or another circuit, for instance. The precondition is a largely clean medium: the thin coiled tubes are cleaned by chemical flushing rather than by brush or lance. If the water carries solids, a filter belongs upstream, or we use the version that can be dismantled.
What decides the economics is how closely the temperatures are meant to converge. The closer they are, the more area the same duty costs - the relationship is covered in the discussion of effectiveness. In the configurator’s live result you can see how the log mean temperature difference changes with your temperatures; we state the heat transfer area in the quote.
Limits stated honestly
Complete heat recovery systems with air routing, fans and an economic forecast lie outside what the Shellcore configurator sizes online - for those, AWS-Technik GmbH as a whole is the right contact. Online we calculate the heat exchanger itself; where the calculation model ends, our team does the sizing. Set up your operating point in the configurator, and we clarify everything else in the quote.
Frequently asked questions
What does a steam application need?
The available steam pressure - the saturation temperature follows from it - the desired temperatures of the circuit to be heated, the condensate outlet temperature, and either the mass flow or the duty. The steam mass flow is derived from the enthalpy balance.
Is waste heat recovery worth it even at small temperature differences?
That is decided by the calculation, not by intuition: the closer the temperatures lie together, the more area the same duty costs. We state the area for your temperatures in the quote, so effort and benefit can be weighed.
Does the condensate have to be drained?
Yes. Standing condensate floods heat transfer area and costs duty; a suitable steam trap belongs to every steam application.
Request a sizing
Describe your application in the configurator - we will come back to you with an individual quote.