Why McLanahan Bedding Dryers
McLanahan Bedding Dryers are designed and built for optimal thermal efficiency to keep operational costs as low as possible. Bedding material is retained in the dryer just long enough to remove moisture and achieve maximum pathogen kill before exiting the system.
High temperatures in the McLanahan Bedding Dryer system quickly and efficiently reduce moisture and kill pathogens that lead to poor cow health and low milk quality. The result is cleaner, drier bedding that can be reused instantly. In the barns, the freestalls are cleaner and more comfortable, ultimately resulting in healthier cows with higher milk production and lower somatic cell counts.
McLanahan Bedding Dryer systems are designed for quick, easy installation with minimal costs. Multiple sizes and many options are available to suit almost any drying need. The most common size systems arrive mounted on a frame. Simply attach and level the feet, mount the required ductwork and collectors, hook up the electricity, connect the energy source for heat, and you’re ready to produce cleaner, drier bedding. McLanahan Bedding Dryers are flexible and can operate on natural gas, propane, diesel, or on biogas produced from anaerobic digestion.
McLanahan Bedding Dryers require minimal operator interaction. Exhaust temperatures are monitored, helping to indicate the dryness of the material. Once a target exit temperature is established and set, the system automatically adjusts to maintain that desired exit temperature, ensuring a consistent final product. To feed the system, a hopper supplies material to the dryer at a constant rate. At the discharge, conveyors move the finished product to the desired storage location. The finished product is ready for bedding with no further handling required.
How Bedding Dryers Work
Bedding Dryers use rotary drying technology to reduce the moisture content in freestall bedding. The wet bedding is introduced into the system along with heat and air. As the material tumbles through the Bedding Dryer, heat and air pull the moisture out. The drier product is collected at the end, while the air and moisture are exhausted.
Bedding Dryer systems contain several key components. The burner and furnace provide a consistent heat source. The insulated drum, which contains lifters and flighting, lifts the material as it rotates and showers it into the heated air. The combination of flighting and air flow move the material through the drum to the discharge end, where a product collector allows the dried material to settle out of the air stream. The air continues to a cyclone, where smaller, lighter material is pulled out. Airlocks control the material and air flow out of the product collector and cyclone. A fan, located at the outlet of the cyclone, pulls the air and moisture through the system and exhausts it to the atmosphere.
A consistent feed is important for the system's operation, so a hopper and conveyor system is used to meter the correct amount of bedding material into the Bedding Dryer. At the discharge end, a conveyor system is used to move and stack the dried bedding.
Popular Applications for Bedding Dryers
Bedding Dryers are well-suited for a wide variety of applications. Some of the many materials that can be dried with a Bedding Dryer include manure solids bedding, sand bedding, paper mill sludge, organic material and chicken litter.
Features and Benefits of McLanahan Bedding Dryers
- Proven to be robust and efficient for optimum performance and long system life.
- Single-pass or triple-pass rotary dryers are available in multiple sizes and configurations to suit most any drying need.
- Systems are engineered for efficient moisture removal with minimal operator interface and little maintenance.
- Smaller units are preassembled and prewired on a frame for fast setup and installation.
- Outputs are monitored and the system is adjusted automatically to ensure a consistent product.
- Unique bolt-on tire design minimizes downtime during tire replacement.
- One-piece furnace refractory ensures longer refractory life.
- Systems come with an automatic fire suppression system in the unlikely event of a high-temperature/fire situation.
Frequently Asked Questions
What is the benefit of drying my bedding with a Bedding Dryer?
Drier bedding will improve milk quality and cow health. Bacteria need three things to survive: moisture, heat and food. If any one of these three things is removed or reduced, the bacteria’s ability to survive is reduced. A Bedding Dryer system reduces the moisture and in some cases actually kills the bacteria in the bedding that leads to poor udder health. For more information on dewatering and drying, listen to our Managing Sand Bedding for Healthy Cows webinar.
How much does it cost to dry my bedding with a Bedding Dryer?
The cost of drying bedding with a Bedding Dryer is driven largely by two things: the cost of electricity (although this is relatively small) and the cost of fuel. If you know your fuel and electric prices, McLanahan's cost calculator can help you determine the cost to dry your bedding.
How do I determine the size of Bedding Dryer?
The size of a Bedding Dryer system depends on these three things:
- The type of material that is being dried. Materials and the moisture that they contain behave differently in a drying system. For example, sand contains only surface moisture, which is removed relatively easily. Manure fibers, being organic, not only have surface moisture but also internal moisture. This internal moisture is often more difficult to remove and requires longer retention times inside the Bedding Dryer. Also, unlike manure fiber, sand is not combustible and therefore can be hit with higher heat.
- The amount of material that is being dried. This is usually measured in tons per hour, cubic feet per hour or cubic yards per hour.
- The time allowed for operating the system. In some cases, the Bedding Dryer system will operate continuously 24/7, but in other cases, it needs to operate during daylight hours, five days a week. In the second case, if the same amount of material needs processed, a much larger Bedding Dryer system will be required.
Want to estimate the size of Bedding Dryer you need for your dairy? View our Bedding Dryer size chart.
Is it safe to have such a large Bedding Dryer in and near my barn and other buildings?
Yes. Each Bedding Dryer has redundant sensors in the inlet and outlet to continously monitor the temperature. If the temperature gets out of range, the burner automatically idles down. In the event of dangerously high temperatures, the burner will shut off and a solenoid valve will open to allow steam or hot water to enter the dryer and extinguish any fires that may be present.
What is the difference between a single-pass Bedding Dryer and a triple-pass Bedding Dryer?
The Single-Pass Bedding Dryer is the workhouse of the rotary drying world. As the name implies, material makes one pass through the drum. It enters at the inlet end, travels the length of the drum and exits. Single-pass rotary dryers are most often used for heavier, stickier and more abrasive materials.
The Triple-Pass Bedding Dryer looks similar to a Single-Pass Bedding Dryer on the exterior, but the interior is much different. The triple-pass rotary dryer contains three drums in one: an external drum, and internal drum and an intermediate drum. Material enters the inlet of the internal drum. It travels to the discharge end, but instead of discharging, it tumbles outward to the intermediate drum where it is pulled back toward the inlet. Once the material reaches the inlet end, it tumbles out to the outermost drum, where it travels once again to the outlet end. Once it gets to the outlet, the material exits the drum. This type of Bedding Dryer is good for lighter materials, such as manure fibers. It allows for lower inlet temperatures and fan speeds but still provides the longer retention time needed by some materials.
What other methods are used to dry bedding besides Bedding Dryers?
Some of the most common methods of drying bedding include fluidized bed dryers, flash tube dryers, infrared dryers and perforated bed dryers.
While each of these systems is capable of drying materials, here are the reasons why McLanahan has chosen to use rotary dryers in their systems.
Can I use other fuel sources besides natural gas to operate a Bedding Dryer?
Natural gas and propane are the most common types of fuel that are used to operate Bedding Dryers, but you can also use No. 2 Diesel as a fuel source. If you have a digester and excess biogas, you can use the biogas as long as it is scrubbed. View our Bedding Dryer Operational Costs chart to see how much fuel is required to dry a ton of bedding.
What happens to all the water that is evaporated from the material through the Bedding Dryer?
The amount of water that is evaporated from the material through the Bedding Dryer can be significant. The water is drawn into the air as water vapor and is carried out of the system through the exhaust ductwork. There are minimal residual fines and the exhaust can usually exit the system outside the building; it will look like a plume of water vapor. In some cases where the exhaust needs scrubbed further, a baghouse can be installed to clean any residual fines that may still be present.