Why McLanahan Sand Bedding Dryers
McLanahan is the global leader in providing sand separation, dewatering and drying solutions for the dairy industry. They were the first to make mechanical sand-manure separation available to the dairy industry and have led the way in providing economical ways to improve cow health through better bedding. They have a global team of dairy experts who are dedicated to providing better bedding solutions for dairies.
The Sand Bedding Dryer is the natural evolution to McLanahan's work with sand bedding, sand separation and sand dewatering. Rotary sand dryers have long been considered work horses in the drying world, as they are used in a wide range of industries. They are simple, robust, efficient and easy to manage. They can be designed and built in multiple sizes to suit a wide range of throughputs.
McLanahan Sand Bedding Dryers arrive pre-assembled on a frame for fast and easy integration into a sand separation system. They can be operated using natural gas, liquid propane, diesel or bio-gas. Once they are installed and set up, minimal operator interface is required. Output temperatures are monitored and the system automatically regulates itself to maintain proper moisture in the output material. In the event the temperature gets too high, the infeed will stop and a valve will automatically open to introduce water or steam into the system.
Unlike many other rotary dryers, the tires are bolted onto the cylinder rather than welded or shrunk on. This makes replacing the tires much faster and easier.
Control panels can be supplied with remote access and monitoring. Text and email alerts can be sent to notify the operator of any changes that might be happening with the system.
How Sand Bedding Dryers Work
Sand is first recovered through a gravity settling system or one of our mechanical separation systems. This recovered sand contains about 12-20% moisture and should be conditioned before it is put back into the stalls. To remove the moisture immediately, a Sand Bedding Dryer can be installed. With a mechanical sand separation system, sand can be automatically conveyed into the dryer. This allows the Sand Bedding Dryer to work with the sand separation system with minimal operator interface. With a sand lane system, an operator will first dump the sand into a hopper system, which will in turn feed the dryer.
A Sand Bedding Dryer is a simple, yet efficient way to remove moisture from sand. As sand enters the drum, it falls into a stream of highly heated air. Flighting within the drum continuously lifts and showers the sand through this heated air stream. This creates a highly efficient heat transfer system while advancing the sand through the drum. The drum is also positioned at a slight downward angle, which helps to move the sand toward the discharge end. The material removal system pulls out the dried sand and deposits it on a conveyor system.
To ensure the sand is consistently dried to the correct moisture content, the inlet and outlet temperatures are constantly monitored. Programming logic takes these readings and automatically adjusts the burner output to maintain the desired outlet temperature. The result is a consistently dried product even with some variances in feed rates and moisture.
Benefits of McLanahan Sand Bedding Dryers
- Recycled sand is dry and pathogen-free
- Recycled sand can be reused immediately
- Sand Bedding Dryers can be added to existing sand separation systems, including sand lanes
- Rotary Dryers have been used for years and are simple and efficient
- Can be used with different energy sources, including natural gas, propane, diesel or biogas
- Overhead drive increases safety, reduces footprint, and reduces stress on the tyres and rollers
- Bolt-on tyres reduce welding and are easier to replace
- Pre-assembled on a frame for quick installation and setup
- Access doors to drum allow for better serviceability and maintenance
- Ceramic-lined cyclone
- Abrasion-resistant plate used in strategic places, such as the flighting and lifters
Frequently Asked Questions
How much does it cost?
The cost of a Sand Bedding Dryer depends on the size of the system and the complexity of the conveyance system into and out of the dryer. Contact McLanahan to get a quote for a dryer that’s sized for your application.
What are some key options to consider?
You can choose from a number of options to tailor the system to your operation. Some of the most common options include:
- A multi-gas train that allows you to switch fuel sources between natural gas and propane, which can come in handy if the prices of gas or propane change.
- A biogas train that gives you the option to fuel your dryer with scrubbed biogas. In this configuration, the train and certain parts are made of stainless steel to counter the corrosive biogas.
- A bag house filter that allows you to capture particles that bypass the cyclone system.
- An automatic weighing station for the hopper to determine the feed rate.
- A feed hopper system to regulate the feed into the system.
What other technologies should I consider?
Two primary methods are used to commercially dry sand: fluidised bed dryers and rotary dryers. Each has pros and cons. Some advantages of using a rotary Bedding Dryer include greater flexibility in feed rates, varying product uniformity and simplicity.
Rotary Bedding Dryers are simple, robust and versatile. They can be used to dry light, fluffy materials like manure fibres; heavy, sticky materials like sludge; and heavy, abrasive materials like sand.
- Rotary Bedding Dryers provide the appropriate resident times for pathogen kill. Temperature and time are the two factors for providing pathogen destruction. Rotary Bedding Dryers provide the right amount of heat and residence time to kill harmful pathogens.
- Rotary Bedding Dryers are forgiving. Inlet and outlet temperatures are monitored and if the incoming feed changes slightly, the burner modulates up or down to apply just the right amount of heat to maintain the product dryness. Some dryers, such as a fluidised bed dryer, require closely graded materials. Rotary Bedding Dryers do not and can dry materials with a wide range of densities and sizes, even if the incoming feed contains this wide range.
- Rotary Bedding Dryers are simple to operate and maintain. Little regular maintenance is required, besides some greasing and oiling. A graphite block automatically keeps the tires lubricated.
- Rotary Bedding Dryers can be constructed from a range of materials to suit the application. Heavy, abrasive materials require an abrasion-resistant plate be used in the drum and lifters. Stainless steel is used for corrosive applications.
Do I need to be concerned about fires?
As with any drying system, fire is a potential risk. However, the opportunities for fire are minimal with sand drying systems that use a single-pass rotary dryer. Sand itself does not burn, so unless there is an abundance of organic material in the sand, there is little chance of fire. Regardless of the material being dried, every system is supplied with a fire suppression system that automatically injects water or steam into the dryer if the temperature gets too high.
What are my operating costs?
Operational costs for a Sand Bedding Dryer are largely dependent on the cost of electricity and gas. Use this calculator to find out approximately what your non-labor costs would be.