Direct steam heating introduces water as condensed steam into the fluid being heated. Most fluids being heated are water, or water-based slurries. In those cases, there is little concern about the addition of water into the process fluid. However, some slurries or fluids are part of a formula or recipe and it is important to know the amount of water that will be added in the direct steam heating process.
Fortunately, calculating the amount of water added by direct steam injection is simple. Steam pressure has no impact on the calculations.
- Calculate the amount of steam required to heat the fluid in your process. Result will be in (lb/hr) or (kg/hr).
- ProSonix has a calculator online which can be used to determine the steam usage. Click here to try our Steam Usage Calculator.
- Add the result of #1 as water to the recipe to determine the final water percentage.
A chemical plant has a desired final product of 20% solids and 80% water. They want to heat the slurry from 104°F(40°C) to 160°F(71°C). The slurry flows at a rate of 44 gpm (10 M3/h).
The Steam calculator shows the above application to use 1,280 lb/hr (580 kg/hr) of steam to heat the slurry. Condensed steam weighs about 8.3lb/gal (1000kg/M3). This equates to 2.5 gpm (0.56m3/h) of water added to the process during heating. For this example, the final slurry would be 19% solids.
If the plant needs to the final solids level to be 20%, they could slightly alter the recipe by reducing the water in the initial batch by 2.5 gpm to accommodate the steam addition. The result would be the desired 20% final solids.
The ProSonix I-Series heater is ideal for heating most slurries or aggressive fluids.
To learn more about heating slurries, visit our Steam Injection Heating for Slurries and Fibrous Fluids page.