A Different Way to Add Powder to a Liquid Process
Introducing dry powder into a liquid process is not simply a matter of moving material from one point to another. When powder is added directly to a tank, clumping and dusting can become concerns. A powder induction system is designed to introduce dry powder into a moving liquid stream so it can be delivered to a downstream process.
For suitable materials, powder induction provides an alternative to mechanically conveying powder directly to a tank. By bringing the powder into contact with liquid before downstream delivery, the process can help reduce dusting and clumping in downstream tanks while helping shorten mix and residence times.
What Is a Powder Induction System?
A powder induction system combines dry-material handling with a liquid stream to wet and entrain powder for downstream delivery. In a typical arrangement, dry powder is introduced at a controlled rate, brought into contact with a motive liquid and then drawn into the moving liquid stream by a venturi eductor.
Hapman’s Solidquid™ Liquid Solid Conveying System applies this approach through controlled feeding, a wetting cone and a venturi powder eductor. The system is intended for dry powders that are free-flowing, free of clumps and capable of being consistently meter-fed. Materials that do not flow reliably can interfere with consistent feeding and may plug the system.
How Does Powder Induction Work?
While every system is configured around the material and process requirements of the application, the fundamental powder-induction process follows three stages.
1. Establish a Controlled Powder Feed
Powder is conditioned as needed, then meter-fed into the system at a controlled rate. The objective is consistent material introduction before the powder reaches the liquid stream.
2. Pre-Wet the Powder
The powder passes through a wetting cone, where it meets the motive liquid before reaching the eductor. This pre-wetting step can help reduce the clumping that may occur when dry powder is added directly to a tank or liquid process.
3. Entrain the Powder for Downstream Delivery
A venturi powder eductor uses motive-liquid flow to create suction. The suction draws wetted powder into the moving liquid stream, which delivers the material to the downstream process. Pre-wetting and entraining the powder can help reduce clumping and dusting and can facilitate better downstream mixing and reduced downstream mix or residence times.
Powder Induction vs. Mixing: What’s the Difference?
Powder induction and mixing are related, but they perform different process functions.
Powder induction is the process of introducing and entraining dry powder into a moving liquid stream. The goal is to wet the powder and move it into the liquid stream for downstream delivery.
Mixing is the downstream operation used when further blending is required. A powder eductor does not perform that downstream mixing operation. With Solidquid™, pre-wetting can help reduce clumping and facilitate better downstream mixing, but the system does not replace mixing equipment when further blending is needed.
What Should Be Evaluated?
Powder induction systems are configured around the specific material and process rather than treated as one-size-fits-all equipment. For Solidquid™, the powder eductor is selected based on the specific powder, liquid, required feed rate, available pressure and downstream process conditions.
Material characteristics, including bulk density and specific gravity, are evaluated when configuring the eductor and supporting equipment. The feeding method, eductor, controls and overall system configuration are also selected around the material and process requirements. Sugar and yeast are examples of materials commonly used in Solidquid™ applications.
From Dry Material Handling to Induction
Powder induction can be part of a broader material-handling approach. Depending on the application, Hapman can integrate Solidquid™ with bag or bulk bag unloading, conveying, metered feeding and controls. Bag dump stations, feeders and lump breakers can also be incorporated to help provide coordinated material flow from dry-material handling through powder induction.
Solidquid™ systems can be configured for batch or continuous operation. Hapman has configured systems with both batch and continuous loss-in-weight feeding arrangements.
Explore Solidquid™
For processes that call for dry, free-flowing powder to be introduced into a moving liquid stream, a powder induction system may provide a coordinated route from material handling through downstream delivery. To discuss Solidquid™ and the material and process conditions relevant to a particular application, contact the Hapman team today.