Iba 2009

Organics granulationBio-Fertilizer & Value-added Waste streams
31st Conference of the Institute for Briquetting and Agglomeration
San Antonio, Texas, USA
September 29th, 2009
Presented by:
Brett Rittenhouse, FEECO International
Brittenhouse@feeco.com
(920) 468-1000

Principles of Organics Granulation
A Technical Overview of Fertilizer Production from Manures and other Waste Streams
FEECO INTERNATIONAL

FEECO – Overview

Who We Are
Worldwide supplier of process equipment
Specializing in Thermal Processing, Agglomeration, Material Handling, and Process Systems
Founded in 1951 as Fertilizer Engineering and Equipment Company.
By the 1960s, we had diversified into Mining, Minerals, Pulp & Paper, and Waste Recycling – and became FEECO International.
Privately held company with about 80 employees

What We Do
Collaborate with Customers
Process Development
Feasibility Analysis
Pilot Plant Testing
Financial Modeling
Plant Design and Engineering
Detailed Equipment and Plant Design
Equipment and System Supply
Project Management – single equipment to turnkey supply

Strengths of our Team
Engineering Staff from all major disciplines:
Chemical/Process
Mechanical
Civil/Structural
Environmental
Electrical
Customer-focused Project Management

Laboratory Services
Our pilot plant can be set up for testing on a single piece of equipment or multiple pieces as a continuous process tying together agglomeration, drying, sizing, and recycling capabilities.
Batch Testing/Feasibility
Pilot Plant Testing (500-1000 lb/hr)
Tolling Plant (24 hr Production Runs)
Analytical Testing

The 30,000’ View
Organics Recycling

Recycling?
“Recycling involves processing used materials into new products to prevent waste of potentially useful materials, reduce the consumption of fresh raw materials, reduce energy usage, reduce air and water pollution, and lower greenhouse gas emissions.” – Wikipedia, September, 2009.

Organic Waste Streams
Agricultural Waste (Manures, Composts)
Industrial Waste
DAF Sludge, Food Waste, Restaurant Waste
Municipal Waste (Biosolids, Composts)

The Ag-Waste Dilemma
Economic pressure pushing towards herd growth
Prohibitively high land costs lead to herd growth without adequate land to dispose of waste
Nutrient levels saturated on fields where it is economically viable to spread
Excess nutrient run-off leads to surface and ground water pollution
Nutrient value of manure does not get fully realized

The Ag-Waste Opportunity
Source of macro and micro nutrients
Nitrogen, Phosphorus, Potassium, Sulfur, Boron
Source of Bio-Energy Production – Anaerobic Digestion
Organic industry as a growth market

Waste Transformation: The Need
Fertilizer demand is increasing
Despite recent setbacks, non-renewable fertilizer prices will continue to rise
US production capacity is shrinking
World food demand is increasing
Increasing competition for land resources (development, energy crops, etc.)

The Organic Food Industry
U.S. sales of organic food and beverages have grown from $1B in 1990 to $20B in 2007, 20.9% growth in 2006.
U.S. sales of non-food organic products were $17.7B in 2006, 26% growth in 2006.
Source: Organic Trade Association

Fertilizers from Organic Wastes
Generally considered a low-analysis fertilizer
Macronutrient content < 10% by weight.
Wide range of feedstocks:
Slurries (<10% solids) – Relatively dry, composted material (>80% solids)
The drier feed material can be finely divided and relatively dusty
Limits application in the field.
Traditional granulation approaches can be implemented to improve the handling, storage, spreading, and utilization characteristics of the material.

Organic Waste Utilization - Recap
Major Driving Force: Growth!
Demand Side Needs
Rising Fertilizer Costs
Trade Imbalances
Local and Secure Source of Nutrients
Supply Side Needs
Increasing Disposal Problems
Environmental Regulation
Need for safe (and profitable?) means of “Nutrient Recycling”

Fertilizers from Organic Wastes

Granulation Process Approaches
Organics Granulation

Organic Granulation Systems
Mixer – Drum Dryer Granulation
Pin Mixer
Paddle Mixer
Mixer – Pan Pelletizer – Drum Dryer Granulation
Dry Pellet Mill & Crumbler

Mixer – Dryer Granulation

Mixer selection based on feedstock analysis
Pin mixer for finely divided particles (chicken litter, compost, etc.)
Pug Mill/Paddle Mixer for sludges, pastes, and filter cakes.
Dewatered liquid manures from centrifuge, DAF effluent

Pin Mixers
Used as pre-conditioning unit or stand-alone agglomerator
One Rotor with Radial Pins
Multiple Feeds
Fluid Ports in Top Cover
Relatively High Speed – Turbulent Mixing Action

Pin Mixer Basics
Turbulent action of the mixer provides thorough mixing of liquid (binder), raw feed, and recycle
Reduces the amount of liquid required for agglomeration
Allows high liquid levels without over-wetting
Reduces chances of segregation due to density differences in feed materials
Reduces the chances of selective agglomeration
Up to 90% of binder liquid can be added in mixer with 10% reserved for finish processing (if necessary)

Pin Mixer Basics
Mechanical work compacts the agglomerate through work between the pins and shell and interaction with each other
Improved crush strength, Less attrition
With a retention time of seconds, the mixer delivers to a finishing pelletizer (if necessary) nuclei that are properly moistened, have adequate density, and are thoroughly mixed with binders, recycle, and multiple raw materials
Can increase on-size product up to 95% (when coupled with Pan Pelletizer)
Can increase capacity of pelletizing disc or drum (nuclei formation in mixer)

Pin Mixer Basics
Mixer may be required for agglomeration to occur in pelletizing disc or drum:
Chemical reaction (Phosphoric Acid Spray)
Reduce moisture level in sludges by mixing with dry recycle
Intimately mix liquid with raw feed (compost)

Pin Mixer
High speed, Multiple feed screws

Pin Mixer
Internal view, during fabrication

Paddle Mixer/Pug Mill
Slower speed, double shaft, mixing paddles

Advantages:
Mixer offers moisture control of granulation process
Simple, closed system
Minimal waste. Off-spec product recycled in granulation loop
Easy binder addition in mixing step
Optimization includes evaluation of:
Pin arrangement
Pin tip speed
Retention time (function of equipment sizing and mixer speed)

Disadvantages:
Oftentimes a tight moisture window in pin mixer granulation limits control
Material handling can be challenging for wet, sticky feed
Require finely divided feedstock – pre-grinding/de-lumping may be necessary
Limitations on achievable granule crush strength (feedstock specific)
Small diameter granule production
Might be desired for “greens” grade product

Pan Granulation

Pan Granulation - Fundamentals
Feed from Pin Mixer fed through articulating feed chute
Small particles at bottom of bed and travel furthest
Largest particles remain in kidney shaped area on top of bed
Competition between gravitational and centrifugal forces resulting segregation by size in tumbling bed

Pan Granulation - Fundamentals
Trajectories defined by particle size
Optimization:
Spray locations
Scraper locations
Pan Inclination
Rotational Speed

Pan Granulation
Advantages:
Very good control over granule size
Improved product quality – polishing on disc
Flexible with binder addition
Disadvantages:
“Open” system – odor, housekeeping, dust, etc.
Labor intensive

Pellet Mill Process - Overview
Raw Manure Unloading
Manure Drying
Size Reduction
Steam Conditioning
Pellet Mill
Crumbling
Fines
Classifying
On-size Product

Pellet Mill Process
Physical Product Differences
Crumble vs. Spherical Product
Energy Usage
Reduction in drying gas requirements
Increase in electrical requirements (pellet mill)
Reliability & Maintenance
Careful with high silica feedstocks

Bio-Fertilizer Plant - Emissions
Gas Treatment
Feedstock specific
Particulate
Wet scrubbing
Form of Nitrogen in feedstock?
Fuel Source? Biogas may involve SOx scrubbing

Selection of Agglomeration Equipment
Parameters of Particulate Feed
Size and Shape
Moisture Content
Material Characteristics
Material Sensitivities (heat, pressure, reactivity, etc.)
Bulk Characteristics
Binding Characteristics
Parameters of Agglomerated Product
Size and Shape
Strength
Green Strength
Final (cured) Strength
Structure
Source: Pietsch, Wolfgang Agglomeration in Industry, Vol 2

Parameters of Agglomeration Method
Batch or Continuous Operation
Capacity Requirements
Wet or Dry Operation
Space and Energy Requirements
Investment and Operating Costs
Site, Supply, Environment, Infrastructure
Relative location to suppliers and customers (raw materials, additives/binders, energy)
Site accessibility and transportation facilities
Climatic conditions
Availability of skilled and other labor
Availability of support functions
Regulations (EPA, OSHA, etc.)
Source: Pietsch, Wolfgang Agglomeration in Industry, Vol 2
Selection of Agglomeration Equipment

Bio-Fertilizer Processing Considerations
Raw Feed Handling
Feedstock specific
Dewatering
Mechanical (presses, centrifuges, etc.)
Advanced separation with polymers
On-farm or Centralized Plant?
Bio-security concerns
Feed Conditioning
Seed pellets formed in paddle mixer with wet feed and dry recycle
Pin or paddle mixer used to blend multiple feed streams
Binder?

Agglomeration
Seed pellets grown on disc pelletizer
Seed pellets grown in rotary drum dryer or agglomerating drum
Binder?
Drying
Rotary drum, fluid bed, etc.
Pathogen Reduction (Time & Temperature)
Product cooling & storage
Rotary cooler, dryer cooling hood, fluid bed, etc.
Gas Processing
Thermal oxidation, exhaust gas scrubbing, PM capture
Bio-Fertilizer Processing Considerations

Overall Mass Balance: Advanced Manure Management

Feeco Bio-Fertilizer Process Flow

Inorganic Nutrient Fortification
Biosolids
Manure
Organic Waste
Sulfuric Acid
Phosphoric Acid
Pipe Reactor
Pug Mill
Drying/Agglomeration Plant
Fortified Granular Product
Ammonia
Benefits of Fortification :
Chemical Heat Release Utilization
Customized grade product
Improved margins, larger markets
Potash

FEECO Bio-Fertilizer Plant, Hog Manure
Plant aerial view

Thank You!

http://feecoblogs.com	23
http://blogcentral.feeco.com	4
http://www.slideshare.net	3
http://feeco.com	3
http://translate.googleusercontent.com	1

Iba 2009

by FEECO on Oct 02, 2009

Accessibility

Categories

Tags

Upload Details

Usage Rights

5 Embeds 34

Statistics

Iba 2009 — Presentation Transcript