United States Department of Agriculture – MAPHEX
Agricultural Research Services
U.S. Department of Agriculture scientists and their collaborators have developed a mobile system for removing phosphorus from cow manure that may offer dairy farmers greater flexibility in where, when, and how they use the nutrient to fertilize crops.
The technology included in the MAPHEX system includes a mounted auger press, centrifuge, vacuum-filter unit, and other components atop two trailer beds so that the entire system could be driven to a farm and operated onsite, either on a daily or rotational basis depending on the size of the dairy operation.
The system can service 10 small farms on a 10-day rotational basis. On a larger farm, such as one with 2,000 cows, the system could operate over 24 hours. MAPHEX works quickly. In about 10 minutes, for example, it can extract 99 percent of the phosphorus from 250 gallons of manure. It also removes the odor from the manure.
Technology Strengths, Weaknesses and Critical Indicators
Centrifuge Technologies remove the non-dissolved particles from the waste stream typically resulting in a lower solid liquid that will not plug equipment or irrigation quality “tea water” depending on whether the technology is used with or without polymer:
- Produces a stackable solid which is high in phosphorus and with significant amounts of organic nitrogen.
- There is significant variation of energy use depending on the site and by technology
- There is significant variation of operational intensity depending on site, use of polymer, and by technology
- There is significant variation of cost depending on site, use of polymer, and by technology
- Can be used with or without polymer. Recovery rates and impact on critical indicators are better when used with polymer.
- Proven technology for nitrogen recovery, phosphorous recovery, storage reduction, GHG reduction, and odor control
Suspended solids/phosphorus recovery technologies:
- Produces a concentrated source of phosphorus from a renewable source
- Include belt presses, centrifuges, dissolved air flotation systems and others
- There is significant variation of chemical and energy use by site and by technology
- There is significant variation of operational intensity by site and by technology
- There is significant variation of cost by site and by technology
1. OPERATIONAL HISTORY