Direct Steam Injection
SKD provides efficient humidity control at low investment cost using existing boiler steam. Multi-Steam™ HD technology reduces wasted energy by up to 85%. The patent-pending Pressurized Condensate Return (PCR) system offers operation with no drain and no maintenance required. No electric or gas humidifier needed.
Applications
Features
- Wide capacity range 2–750 kg/hr
- Multi-Steam™ HDR: Recovers 85% of wasted energy (patented)
- Multi-Steam™ HD: Lowest heat transfer, short non-wetting distance
- Patent-pending Pressurized Condensate Return (PCR) — no drain
- Unique Electronic Steam Controller (SKDESC)
- Centralized wiring (sensors, valves, humidity controls)
- BACnet or Modbus compatible (optional)
- 100% stainless steel construction (rated 360°C)
- Multiple model options: HDR, HD, SD, Mini-Rack, Multi-Tube, Single-Tube
Technical Specifications
Direct Steam Injection Humidifier
The SKD direct steam injection system uses low pressure steam from an in-house boiler to humidify the air.
Direct Steam Injection System
Every SKD Steam Injection Humidifier comes with all required accessories for a complete installation. Depending on the selected configuration, we will supply:
System Components
Supplies condensate-free steam to the steam control valve, while discharging condensate to the steam trap.
Provides full modulation of the low pressure steam flow for a better control of the humidity level.
Multi-Steam™ SD, Multi-Steam™ HD, Jacketed Single Tube, Multi-Tube, or Mini Rack configurations.
Monitors steam temperature and detects abnormal condensate level to ensure safe operation.
Eliminates condensate from the steam line, improving system efficiency.
Controls steam supply to the jacket in a Multi-Tube configuration (mandatory as per ASHRAE standard 90.1).
Optional patent-pending pressurized condensate return system — no gravity drain required, returns condensate to steam source.
Factory configured direct steam humidifier controller.
Multi-Steam™ Steam Distribution
This configuration consists of multiple vertical dispersion tubes mounted on a single horizontal header. Upon a demand for humidity, the ESC controller slowly opens the steam modulating valve feeding steam to the dispersion tubes.
Jacketed Tube Steam Distribution
This configuration consists of a single tube or multiple horizontal tubes on a common vertical header. Upon a demand for humidity, the ESC controller opens the isolating valve to preheat the outer jacket. This prevents any condensate from forming in the inner tube that could wet the duct or AHU floor.
Pressurized Condensate Return System (PCR)
In steam humidification systems, some of the steam condenses as it travels through the dispersion tubes into the duct, forming water (condensate). This condensate must be removed; otherwise it leads to water accumulation, corrosion and bacterial growth inside the duct. The traditional approach is gravity drain or re-evaporators.
Re-evaporators are devices that re-boil the condensate on a heating element. However, they require regular de-scaling, systematic maintenance and header access; capacity drops when fouled and the system may go offline.
The Neptronic PCR system takes a completely different approach: it returns condensate directly to the steam source under pressure, without relying on gravity or reheating. It requires no maintenance and provides real-time monitoring with BMS integration.
Why should you choose a humidifier with a PCR system?
| Description | Neptronic PCR System | Re-Evaporators |
|---|---|---|
| Why use it? | No gravity drain required. Return humidifier condensate to steam source rather than waste to drain or complicated re-pressurization systems. | No gravity drain required. Return humidifier condensate to steam source rather than waste to drain or complicated re-pressurization systems. |
| Real-time monitoring | Yes | No |
| BMS integration | BACnet or Modbus | No |
| Maintenance | Not required | Systematic verification is a must* |
| Cleaning | Not required | De-scaling* |
| Downtime | None | During maintenance or when equipment offline due to fouling* |
| Flooding of header | None | Possible due to reduced capacity from fouling and standard piping configuration* |
| Accessibility | Outside the duct for easy access | Standard cleaning procedure requires access to the top of header (may require duct access door)* |
| Compatibility | Insulated and non-insulated steam distributors and headers | Only insulated steam distributors and headers |
| Installation | Lowest clearance with simple and flexible installation due to small modular components | Higher clearance and integral design forces components below duct, resulting in potential ceiling clearance issues* |
Documents & Downloads
Technical data sheets, catalogs and installation manuals
Applications Using This Product
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