Byproduct
Processing
Alternative Energy
(Biomass, methane, ethanol, biodiesel)
Innovative
Agriculture Projects
Business
Development
and planning
The Problem
Several years ago the agricultural community embarked on a new opportunity in poultry for the small farmer. Because of integration in the poultry industry farmers can contract to raise large flocks of broilers on their property. This exchanges the farmer's capital, labor and expertise for a predictable annual return, offering considerable security and stability. However, this venture is not without problems since the waste produced in the poultry houses can be a large volume problem for the farmer, the rural community and the area water supply.
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Land application of the poultry litter requires timing for maximum effectiveness for the crops and to minimize leaching of the nutrients into the area watersheds. Since the houses are cleaned on a schedule that may not coincide with the most appropriate time for land application, storage of the litter is also an important issue. Odors, flies and leaching of the stored litter have become current topics in the newspapers and town meetings as poultry has grown.
Regardless of the benefits that land application of litter brings to the soil, we know that this is not the total long term solution to utilization of the poultry waste. Other uses have to be found before the soils become overloaded with phosphorus and the leaching becomes a problem in the water. Poultry litter has qualities which make it a valuable resource for more than fertilizer. It also contains nutrient and mineral qualities for a feed ingredient. Virtually every poultry state has university studies showing and recommending broiler and layer manure as a ruminant feed ingredient.
While poultry litter may have a cash value as a fertilizer which varies from $4 to $30 per ton it has value only as long as the soils can take advantage of it nutrients. Cattle are not static assets as is land. Cattle are born, raised and move on. New cattle take their place daily. These farm assets are a significant cash crop and have the potential to be more so as Kentucky farmers diversify.
One of the most costly aspects of raising quality cattle is the feed provided for them in the winter and in the heat of summer when many forages are not producing at their peak. The unfortunate drought conditions experienced in many parts of the South and Midwest over the past two years are expected to continue year. This has more significant results for cattle farmers due to forage supplies having been used last summer and leaving less for the wintering of cattle. If only one cutting of hay is made this year as in past drought years, forage will be in short supply again.
If we feed our cattle in August and September the hay that was stored for winter use, the cattle profits in Kentucky will dry up with the parched soil. An alternative feed that is both safe and nutritious would be a boon for the cattle farmer. It would allow him to economically react to the weather patterns while supplying his cattle with the ingredients necessary for a profitable operation. If poultry litter can provide a pathogen free feed ingredient with no antibiotic carryover at a cost of fescue hay but the benefits of a higher grade feed, it would be a big step in short stopping problems for the poultry grower and be a benefit to the cattle men. Even when drought is not an issue, the processed litter makes an economical and safe feed ingredient for cattle.
The Issues of Safety
All university studies of poultry litter being used as a feed ingredient focus on the issue of safety besides that of economy. The usual way to render litter free of pathogens, parasites and antibiotics is to deep stack it allowing natural biological and chemical processes to help ensure a safe product. Deep stacking requires a place out of the weather for storage, proper monitoring of the temperature and moisture of the stored litter. Occasional turning of the litter may be necessary in order to help ensure that the outer layers are as well processed as the interior. This is an additional demand on the time and talents of the farmer. Not only is the litter a storage problem where space and capital may be in short supply but the monitoring and record keeping requirements of this process take valuable time. Additionally, the expertise needed to make the measurements and to react to them when out of line, is a learned skill not found everywhere.
While deep stacking is a common form of litter treatment it is mostly done in roughly effective manner which is far from efficient. It would not take many bad experiences in feed contamination before this practice fell out of repute with the consuming public. In spite of its economical opportunities it is not well handled in all cases and offers great risk for pathogen carryover and pathogen reintroduction after processing.
Options
Mechanical processing of poultry litter offers the cattle feeding customer a pathogen free, safe feed ingredient which makes use of its nutritional qualities. No longer is this a disposal method for a noxious byproduct. It is now a responsible, safe, and economical opportunity for supplemental feeding of cattle.
The processing is done using litter freshly removed from the poultry buildings relieving the farmer of storage costs, risks of vermin infestation, odors and leaching. Whether onsite processing or central processing proves to be the most appropriate in a given situation, the waste is converted into a valuable feed ingredient which is far removed from the potentially harmful product it was.
Extrusion involves the homogenization and sterilization of a product through pressure and heat. The heat is generated by the friction resulting from the product being passed through a series of resister plates under pressure of a screw auger. The sudden decrease in pressure when the product is discharged into the atmosphere results in expansion thereby rupturing the cell structure and exploding the product. Dry extrusion generally produces heat in the range of 250 to 300 degrees F, which is sufficient to sterilize the product of pathogens especially considering the pressure generated and the cell rupturing from release after processing. The coincident denaturization of enzyme inhibitors allows the normal enzymatic breakdown and utilization of proteins, fats, and carbohydrates by the cattle. Thus the combined benefits of dry extrusion are:
The benefits of mechanical processing over any other form of processing litter into a feed ingredient are overwhelmingly in its favor. No other form of processing gives such a high degree of confidence in the safety and efficiency of the product.
Production
The feed ingredient manufactured by the extrusion processing litter is a safe and nutritious product. An article in Progressive Farmer (August, 1994) described calf gains of 2.8 pounds per day on poultry litter pellets (70% poultry litter mixed with 5% alfalfa meal, 5% feather meal and 20% corn) fed at a rate of 5 pounds per head per day. Various state extension services have recommended feeding rates of up to 18 lbs per day per head not inclusive of supplemental hay and mineral, as needed. The supplemental hay is chiefly to keep the rumen active and is needed only in amount of about 2 lbs per day per head. Feeding of other byproducts can relieve the need for hay altogether.
Our joint venture process in Georgia produced extruded poultry litter using peanut hulls for bedding material. Peanut skins are added as supplemental fat. The resulting product is 23.74% P and 2.47% Fat at 75% DM and 12.6% C Fiber.
Processing
If the poultry producers in a given area have a sufficiently dense population to justify a central processing facility for turning poultry litter into feed, the litter can be moved upon clean out to a large processing area. This litter will be stored under cover in order to preserve its nutrient qualities until processing.
Sufficient equipment would be onsite to process the litter under a 24 hour per day, 5 day per week program. Certain ingredients would have to be added to the litter to facilitate processing and in this case fat is needed. This can be obtained by using whole soybeans in the process, adding spent restaurant grease, or mixing with a small amount of hog waste. Even poultry mortalities can be used since the extrusion process not only renders the dead birds pathogen free but also very effectively processes what would otherwise be inedible portions of the carcass. The extrusion technology is an FDA approved alternative rendering technique.
After extrusion the product's biosecurity must be maintained to prevent post-extrusion contamination. Therefore, the cooled and dried product is stored in bins at 10% moisture or less. The fat content would be maintained low enough to allow flowability and to discourage degradation of the product over time.
In some cases it may be most efficient to process litter on the site of the poultry houses. In these cases the extruder, mixer, cooler and drier could be trailer mounted.
Processing Costs
The extrusion process would take place indoors. The necessary building and equipment costs are estimated at $300,000 for a minimum setup, exclusive of operating capital. A small building with storage for the raw litter and bins for the finished product, plus equipment to do the processing are the total package.
Since the equipment is essentially modular, once a satisfactory site has been found a small facility can grow to any size within the limits of the building and lot. Some growth is anticipated beyond the minimum plant size in order to take advantage of economies of scale. But, other small facilities may also be planned for diverse poultry operations not within economical transportation distances of the larger plants.
In order to handle the machinery and movement of product, scheduling deliveries and marketing the feed, 2 employees are needed on the day shift of each small plant. They will be able to process up to 3 times the volume of a small facility in the event the plant grows with the need. One small plant can process 2,000 tons of litter per year operating 5 days at 8 hours per day. It can do three times that much by operating 24 hours a day with the help of 2 employees per extra shift. The maximum production of a small plant is then 6,000 tons per year of feed ingredient. The plants utilize the same amount of litter as their final production of feed due to shrinkage from moisture loss offsetting the added fat ingredient. Thus, a 6,000 ton feed plant uses 6,000 tons of litter.
In the large scope of things it is not very efficient to have such underutilization of personnel as we see in a small, one extruder plant but with material movement and duties with drivers and customers, one employee can not be expected to be able to handle the plant by himself. Yet once the employees are in place additional equipment can be installed to bring a single plant up to three times it original capacity with no increase in manpower. This means that the 24 hour shift arrangement could process 18,000 tons of litter per year with only the plugging in of additional modules of equipment, chiefly 2 more extruders.
6,000 ton per year plant can breakeven even if it is responsible for total debt repayment. This is true only if it is part of a larger system since its share of the administrative burden is insufficient for it to be a stand alone plant and still repay the debt and purchase the litter.
Even at this plant size the required personnel are not kept productive. The plant would have to expand to 18,000 tons per year to effectively utilize the employees. This would require the litter from 90 poultry houses, which is achievable, since at this level of production the farmer could be paid $10 per ton for his litter, delivered. However, at 5 lbs feed per day it would require 20, 000 head of cattle. Even at the higher recommended feeding rate of 10 lbs per day it would require 10,000 head. This is not a large feed lot size.
To use the personnel effectively would require a supplemental program at the same facility. Two options are readily available. Separated hog manure solids can be extruded with whole soybeans to make an excellent cattle and hog feed ingredient. It also may have potential in aquaculture due to the high protein and fat levels (39% P and 14% fat). Alternatively, whole soybeans could be extruded and the oil pressed out of the meal to make a high fat soybean meal and a mechanically extracted soybean oil using separate pieces of equipment but the same personnel.
There are a considerable number of options once the facility is built and the personnel on board. This is very versatile equipment. Since this is an FDA approved rendering process, a great variety of work can be done safely and responsibly using it, depending on local needs and conditions.