How to Granulate Mushroom and Medicine Dregs Successfully?

If you are trying to turn waste like used mushroom substrate or herbal medicine dregs into fertilizer, you may have found it is not easy. These materials are valuable, but they are also very hard to granulate. They are light, fibrous, and not sticky. At Fude Machinery, we specialize in solving these tough granulation problems. This guide will show you exactly what to pay attention to, so you can successfully turn these dregs into high-quality organic fertilizer pellets.

Last updated: July 2025 | Estimated reading time: 11 minutes

This article will teach you:

• Why are mushroom and medicine dregs hard to granulate?
• What is the secret to making these light materials stick together?
• How do you choose the right granulator for the job?
• What is the complete process from raw dregs to finished pellets?

Why Are Mushroom and Medicine Dregs So Different?

Mushroom dregs and medicine dregs are difficult to granulate because they are very light, full of long fibers, and have almost no natural stickiness. Without special handling, these materials will not form into strong, round pellets and will just remain a fluffy powder.

Unlike animal manure, which is dense and naturally cohesive, these dregs present unique challenges. Their high fiber content prevents particles from binding together. Their low density means they fly around and are hard to control in a machine. Most importantly, their lack of stickiness means that even if you can press them into a shape, the pellets will be weak and will easily crumble back into dust. To succeed, you must change the physical properties of the material before you attempt to granulate it.

dregs of a decoction

mushroom dregs

The 3 Key Factors for Granulating Dregs

To turn this fluffy, non-sticky powder into solid pellets, you must focus on three critical factors: moisture, fineness, and adding a binder. Getting these three things right will guarantee your success.

1. Crushing the Fiber into a Fine Powder

You must crush the dregs into a very fine powder before anything else. Long fibers are the biggest enemy of good granulation. Shredding these fibers increases the material’s density and its ability to stick together.

This is a non-negotiable step. You need a machine that can effectively shred the long, tough fibers found in mushroom substrate and medicine dregs. We strongly recommend using our semi-wet material crusher. This machine uses high-speed rotating blades that tear and shred the fibers, which is much more effective than simply trying to hammer them. The resulting fine powder is the perfect foundation for building strong pellets.

2. Getting the Moisture Content Perfect

For these light materials, the ideal moisture content for granulation is typically between 30% and 40%. This is slightly higher than for other materials. The right amount of water acts as a bridge between particles, helping them stick together.

Think of building a sandcastle. If the sand is too dry, it’s just powder. If it’s too wet, it’s just mud. You need that perfect level of dampness. The same is true here. You can test the moisture by hand. Grab a handful of the mixed powder and squeeze it hard. It should form a clump in your hand but not drip water. If it falls apart, it’s too dry. If water streams out, it’s too wet.

3. Solving the Stickiness Problem with Binders

Because these dregs are not naturally sticky, you must add a binding agent. A binder acts like a glue, holding the fine powder particles together to form a strong pellet. This is the secret to making durable pellets from light materials.

This is the most common step that people miss. Without a binder, your pellets will be very weak. There are many simple and low-cost binders you can use. Bentonite or clay soil are excellent choices as they are cheap and very effective. Other options include starch or lignosulfonate. You only need to add a small amount, usually 3% to 5% of the total weight. You must use a horizontal mixing machine to ensure the binder is distributed evenly throughout the powder.

Choosing the Right Granulator Is Crucial

For light, fibrous materials like mushroom dregs, a standard disc granulator will not work well. You need a machine that uses powerful mechanical force to press the material together. Our new type organic fertilizer granulator is the best choice.

This machine is specifically designed for difficult organic materials. It uses a high-speed stirring paddle inside a cylinder to create intense force. This action physically squeezes the powder together, forming dense and uniform pellets. It does not rely on gravity and the material’s own weight like a disc granulator does, which is why it works so well for fluffy powders. Using the wrong granulator will only lead to frustration and poor results.

Frequently Asked Questions (FAQ)

Question 1: Do I need to compost the dregs before granulating?
Yes, we highly recommend it. Composting with a compost turner  helps to break down the complex organic compounds in the dregs, stabilizes the nutrients, and kills any potential contaminants. It makes the final fertilizer product much safer and more effective.

Question 2: What is the cheapest and easiest binder to find?
For most situations, the cheapest and most accessible binder is natural clay soil or bentonite. You can often find a local supplier of powdered clay. It works extremely well and is very cost-effective.

Question 3: After granulation, are the pellets ready to be sold?
Not yet. After the granulator, the pellets are still moist and soft. They must go through a drying and cooling machine. The dryer removes excess moisture to make them hard and stable for storage. The cooler brings them to room temperature to prevent them from getting damp again. This final step is essential for producing a professional, high-quality product.

Conclusion and Your Next Steps

You now know the special secrets to successfully granulating difficult materials like mushroom dregs and medicine dregs. It is not about having a single magic machine, but about following the correct process. The keys to your success are: fine crushing to destroy fibers, carefully controlling moisture, adding a binder to increase stickiness, and choosing a powerful granulator that uses mechanical force. By following these steps, you can turn this challenging waste into a high-value, profitable product.

Are you ready to create your own high-quality fertilizer pellets? At Fude Machinery, we have the experience and the full range of equipment to build a complete fertilizer production line  for you.

About Fude Machinery
We are Fude Machinery, a professional manufacturer of organic fertilizer equipment located in Zhengzhou, China. Since establishing in 2015, we have dedicated ourselves to providing complete, one-stop solutions. Our factory-direct model ensures you receive high-quality, reliable machinery at the best price, supported by a team of experienced engineers who will guide you from design to installation.

Contact us today for a free consultation. Let’s work together to design the perfect granulation solution for your specific materials.