Some foodservice professionals consider pulpers a more eco-friendly alternative to garbage disposers. These units grind up waste and remove water to reduce a foodservice operation's waste stream. But deciding whether to purchase one of these units and which system is best can be tricky unless you have the right knowledge base. Read on to learn more about pulpers. 

Pulpers: An Overview

Large commercial pulpers utilize big cutting disks, a water press, a recirculating trough system and a 7 to 10 hp motor to consolidate and remove wet waste from disposables.

These units offer various energy and water consumption options, depending on the design.

There are two pulper categories. Close coupled or standalone systems are less expensive and don't require a custom build. The pulping and water extraction are facilitated at the same place. This results in a less complicated installation and less cleaning overall is required because there are no remote lines that have to be maintained.

Remote systems utilize a macerating chamber that grinds food waste then pumps it to a water press in a remote location, such as a back dock, pulp collection room or somewhere away from the input area. This type of system can be fitted with several macerators hooking into one water press. The discharge unit can be placed by the dumpster to save labor and additional grinding tanks can be added if there is more than one dish room. Operators also can have several grinding stations go to one discharge station when using a remote pulper.

Depending on the unit, pulpers can process between 300 and 1,000 pounds of waste per hour. Although these units can accommodate Styrofoam and plastics, stretchy plastic wrap is not recommended for disposing in these systems.

Pulper housing is typically made of heavy gauge stainless steel, while the cutter blades are a tungsten steel that can hold an edge.

How to Know When to Replace a Pulper

To avoid permanent damage, foodservice operators should immediately assess pulpers not functioning properly. Here are five signs it might be time to replace a pulper.

Ineffective operation: Pulper cutting mechanisms can fail, but on occasion rebuilding is an option. If this step proves too costly or in the case of an older unit, the operator should replace the system.

Inadequate maintenance: Operators have to commit to maintaining pulpers by replacing the cutter heads, press and brushes, while greasing bearings regularly. Lack of proper care for this equipment will likely compromise its service life.

Longer grind times: If the pulper takes longer to grind the same amount of waste, the cutting blades may be loose or need replacement.

Loud noises: Unusually loud grinding or whizzing sounds from the pump motor may indicate that debris and contaminates are compromising its operation. This can negatively impact the pulper's operation, making it less effective and causing irreparable damage if the operator does not promptly address the situation.

Less water circulation: If the water volume circulates substantially less than normal, this may indicate that a new unit is necessary.

Pulper Applications

Although operations serving between 1,000 and 3,000 meals at a time often represent the target market for pulpers, an increasing number of smaller foodservice operators now utilize this equipment.

A pulper's prime function is to consolidate waste, which can reduce garbage mass 80 percent to 95 percent on average. Pulpers also can save labor, since the trips to the dumpster can be significantly reduced.

Pulpers are environmentally friendly, extracting gray water and recirculating it to help grind up and dispose of organic waste. This reduces landfill garbage, but also results in less waste being transported through the operation, which enhances cleanliness.

Maintaining Pulpers

Pulpers require daily maintenance for smooth operation and to prevent frequent breakdowns. The following is a laundry list of tasks that can help operators generate a long service life from these units.

  • Regularly clean the unit, particularly the extractor piece — a big corkscrew surrounded by a mesh screen.
  • Clean the grinder tank daily basis and cleaning should be in proportion to how many inorganics are inside. Some items float to the top and require daily straining.
  • When cleaning this equipment, it's necessary to drain it, hose it out with hot water and clean out the food particles.
  • Cardboard can be run through the pulper to help displace stuck food particles.
  • Sometimes units include injection ports for ammonia sanitizers to be sprayed in, which helps kill bacteria in nooks and crannies. This also can keep garbage smells at bay.
  • Manufacturers recommend opening up pulpers at the beginning and end of use to make sure heavy amounts of waste aren't left in the machine. This can lead to foul odors.
  • Check pulper blades on a regular basis. Dull blades will compromise the unit's effectiveness.
  • Most pulpers have inspection plates on the side that can be popped off to access the auger brush, which needs replacement every 18 to 24 months.
  • Depending on the water quality used, the pulper may have to be delimed or descaled on occasion.
  • An engineer or plumber should inspect the drain or circulation line yearly to ensure there are no backups.

Spec Check: Pulpers

Waste removal costs are a good indicator as to whether a pulper is financially feasible. Here are a few other factors foodservice operators should weigh when purchasing a pulper.

Amount of Waste: Operators should look at their current waste amounts to determine if it warrants a pulper. A large pulper system can process substantial amounts of waste, up to 1,000 pounds per hour.

Type of Food Products: Assess the type of food and how it's served. Foodservice operations utilizing compartmentalized trays or china with linen napkins won't use the pulper as extensively as a restaurant using paper plates and milk cartons. This is why these units are more often found in cafeteria-style operations as opposed to high-end restaurants.

Dishroom Design: Make sure the dishroom's layout can accommodate a pulper. The scrapping logistics also are a factor.

Type of System: Determine whether a standalone or remote system is necessary. Remote systems require piping to and from the press as well as transfer pumps between the press and macerator.

Local Laws: Operators should check with local codes to ensure pulpers are not prohibited. Some larger cities, such as New York City, forbid the use of this equipment for commercial applications, while Washington, D.C. encourages it.

Silverware Catcher: For operations utilizing silverware, a magnet option will help catch utensils before they get ground up in the pulper.

Energy Efficiency and Pulpers

Some manufacturers predict there will soon be more energy-efficient pulpers that include motors needing less torque.

Pulpers are known for being environmentally friendly. Whereas a standard cold water disposer uses 14 gallons of water a minute and a recirculating system uses 7 gallons of water per minute, a pulper uses just 2 gallons of water a minute.

By removing most of the solids out of the water strain, water usage is reduced There also is a new vacuum technology for these systems that utilizes no water.