SOLID WASTES IN 'DB MEA" PACKLNG INDUSTRY* GERALD FRANKE Iowa Beef Processors, Inc. Dakota City, Nebraska

We in the meat packing industry are abundantly blessed with pollution problems. As the anti-pollution forces have gained popularity, we have been hit on all sides because of our air, water and solid wastes pollution. Water pollution is by far the most popular Issue. In the past few months, I have filled out forms for the State Government, Environmental Protection Agency, Corps of Engineers, and last week, of all people, Department of Internal Revenue, All were concerned with the characteristics of the waste water discharges from our plants.

The water pollution problems we face, although serious in dollars expended, are somewhat less serious from a technical standpoint than our solid waste problems because we at least have consultants to turn to. Again in the air pollution problems, mainly those of odor, there are qualified consultants available to help us meet the odor criteria.

Our solid waste problems, however, appear to be unique to our industry and as yet very little technical help is available to us. Every beef we slaughter has 50 pounds of stomach contents that we must dispose of. Until recently we had no acceptable manner to handle this material and indeed no one to turn to to offer us a ready-made solution. IBP believes that we have found a method that is ecologically sound and economically feasible. I'd like to pass this along to you today. In addition, we will discuss the other sources of solid waste coming fromthe packing house and our solutions to them.

Since IBP is beef oriented many problems that are discussed in this paper will not have an application to pork plants. However, we do have problems in common and I hope that you my be able to glean something from what is presented today.

Sources of Waste

The main sources of waste in the slaughter plant are listed below.

Stock Pens. The live animals are received in concrete stock holding pens that will cover two to four acres. The animals remain in these pens for from 2 to I2 hours prior to slaughter. The droppings from these pens are generally removed daily by flushing with water. These wastes can

* Presented at the 25th Annual Reciprocal Meat Conference of the American Meat Science Association, 1972. contribute significantly to the suspended solids loading and the BOD if they are not handled properly prior to discharge to the sewage treatment system, The anirml can carry slgnlflcant amounts of mud and manure in on the hide, particularly in the rainy sea~onsof the year. In our plants we have demenuring and fleshing mrchines which remove these materials and deposit them in the aewera.

Kill Floor. On the kill floor the previously mentioned stmach contents will average 50 pounds per thousand pounds of live weight. We design our facilities to handle these materials separately to prevent them from contri- buting to the sewage loading in our plant effluent. In addition, there are product losses that are unavoidable and some that, although they are avoidable, are generally relegated to dumping into the sewer and must be handled in our waste treatment system. An additional source of solids that require special handling include hair, hide trim, ears, face pieces resulting from the hide trimming operation.

Other Sources. Other sources of solid waste include the waste from the ln-plant; treatment systems. These include the grease skimmings from skimming basins and air flotation systems and the bottom sludges that settle out in these treatment systems. In addition, there are the containers and packaging materials that are indigenous to most of our operations.

Solids Handling and Disposal Methods

Pen Wastes. Our stockyards are sloped approximately 1 foot per 100 feet away fromthe plant. At the end of the stockyards we have constructed a long pit with a sloped bottom. The washings from the stockyards empty into this pit. A water level of approximately two feet is maintained to give enough residence time to allow the solids to drop out. We als3 route the demanuring water from the hide fleshing machine and the bottom solids from the air flotation units to this pit. The pit itself is approximately 9 feet wide and is generally six feet deep. Beginning at one end of the pit the flDor has a 6% slope from ground level down to the bottom of the pit. We then have a long 30 to 40 foot horizontal section at the end of the incline. Off to one side at the deep end of the pit, we have a weir sectim. The weir section has a suspended plate to hold floating solids out and removable 2' x 6" boards standing on edge from the bottom up to approximately 2 feet high that will hold back settled solids. The water must flow down underneath the suspended weir which holds back the floating solids and then up over the bottom weir before the clarified water can be discharged out the exit sewer, In order to clean this pit, we remove the overflow boards slowly and allow the water to drain out. This leaves a thoroughly soupy material in the pit for removal. We go into the pit with a front end bader, pick up the Illaterial and drop it into a feed wagon or a honey wagon for field disposal. The cheapest method we have found is to take an old feed wagon with a side discharge, run it aut to a field and discharge it onto the field in windrows. The windrowing has resulted in continual complaints and as a result of this we are exploring an alternative method in our Emporia, Kansas, operat ion. In Emporia, Kansas, we are building a deep pit approximately 6 feet square and 6 feet deep to the side of the manure pit. In this pit we are installing 8 self-priming Gorman Rupp pump that will pick up the incoming water as it comes into the pit, take it up over a Bauer type screen. According to our test the Bauer type screen is quite effective in removing these settleable SOlid8. These solids will then be dropped into a conven- tional manure spreader in much dryer form than what was received in the old gravity settling operation. The weirs in the manure pit will be left in place 80 that if the pump were to fail, the pit would simply fill up and continue to operate in the old manner. We believe this will solve to a great extent the problems that were faced in spreading the wet material in the fields . We explored several methods of dry cleaning the pens and none of them appeared too satisfactory to us. The cost of the equipment and the labor to clean the pens w8s far in excess of the improvements realized with such dry cleanup. We felt the time and dollars expended would be more profitably spent in more fruitful areas of waste reduction in our plant.

Stomach Contents

The most common method of handllng paunch contents is to flush them down a sewer, and then screen them back out of the sewer in order to haul them itway. The paunch contents are usually deposited in a land fill. According to our Sioux City authorities the only way they have been successful in land filling paunch has been to incorporate it with brush. That has been the only benefit we have found to Dutch Elm disease. According to our lab analysis the juices from the paunch have a B.O.D. of 100,000 mg/l. It is easily seen that this can be a major source of waste strength from a packing house using this method of disposal. After much trial-and-error we have developed an acceptable method of disposing of the punch contents by spreading them on farm fields. We handle this material "dry." That is, we prevent any excess water from entering the system. On the kill floor, our receiving table has a series of bars on the table surface that allow excess water to drain away as the stomach is pulled toward the paunch drop area. The stomach is opened and the stomach contents are allowed to drop into a screw conveyor located at floor level. The stonrach is then washed over an umbrella to further remove the remaining punch contents clinging to the surface of the tripe. This wash water is allowed to go to our air flotaticm system. The paunch contents are screw conveyed to a grinder. This grinder will chew up any twine that the anlmal may have consumed and will also grind up the tripe that are xcasionally dropped and not retrieved by the operations people. One of our biggest complaints before the installation of the grinder came about in one Df 3ur plants when one lady's dainty white poodle came dragging home a 10 pound tripe from our paunch disposal area. The grinder is an old 10" Reitz prebreaker that we had removed from one of our rendering operations. 'i'he grinder has operated a year and has given us virtually no problems and has solved a great many problems in our spreader truck operation. After the grinder the paunch contents drop into a blow tank that has the capability of approximately 2 hours production. Once the blow tank is filled, the paunch contents are blown to an elevated storage tank located outside the plant. We have successfully blown this material for distances of 700 feet at elevation differences of 45 feet.

The elevated holding tank has the capacity to hold one full days paunch production. The tank is elevated eufficiently to allow the spreader truck to back under the tank to receive the paunch contents. The tank itself is insulated with urethane foam to prevent freezing. To prevent the solids and water from separating, we have a screw conveyor in the bottom of the tank that turns continually when paunch is in the tank. The auger rotates approximately 10 rpm and serves to sufficiently stir the paunch to prevent solids and liquids from separating.

The spreader truck is specially designed for our purposes. The basic design was patterned after a fertilizer spreader marketed by Peiester Mfg. Co. of Minden, Nebraska. A screw at the bottom of the V bottom tank is used to discharge the punch. A hydraulically operated knife valve completely seals the tank to prevent leakage on the way to the field. The spinning plate rotated by a 25 €€Phydraulic motor distributes the paunch evenly across the field. In the spreading operation the truck begins its pass down the field, the knife valve had opened, the spreader plate is spread into motion and only then is the auger started to discharge the paunch. The tank can hold approximately 10 tons of paunch content per load. The truck is a 2 1/2 ton vehicle with an all-wheel drive. The tires themselves are extra large balloon tires and have proven invaluable in this spreading operation. The development of this truck is evolved over a period of four to five years and in the last two years we have been using the current operation. In the past two years we have experienced no conditions 9f inclement weather that prevented proper epreadlng of the paunch 3n the fields .

In the winter time when fields are not In cultivation it is possible to spread practically all fields with one thin layer of paunch. With snow and ice conditions on the fields the paunch does not cause a problem during run off conditions because of the light application rate. In the springtime during extremely wet conditions, it is necessary to spread the paunch on sod or grassland. It is preferable to have sandy soil to lessen the possibility of miring the truck.

During the growing season the paunch contents are spread on a small field of 40 to 60 acres. The size of the area is predicated on the amount Df paunch contents to be spread. We feel it is desirable to disc the field once each week, therefore the size of the field is generally determined by the slaughter capability. The figures indicate that approximately 3 tons of paunch content per acre is a satisfactory application rate. This would mean for every 120 cattle slaughtered per week, one acre of ground must be prwided . Once the field is covered, and again this should be on a weekly basis, the field is disked and once disked no paunch contents are visible. Reapplication can follow immediately after disking. We have used the same field for periods of 3 to 4 months, then cropped the land the following year. In extremely tight soil, the paunch contents serve to loosen up the soil and provide beneficial effects for -her cropping. The fertilizer value is self evident.

The odor problems from this process are minimum. There is some odor during the spreading operation. The material is generally dry in 30 minutes to an hour after spreading and the odors then fade away. Beginning in late June we add a Dow insecticide that is USDA approved to prevent fly production. This is proven extremely effective and no fly problems are encountered. The operation is not without its problems, but in our estimation, it is the best system that we thus yet have seen in operation. The results have been viared by both the State Board of Health in Nebraska and the Kansas State Department of Health and various officials from the Environmental Protection Agency. They have all had the highest of praise for the operation. It's theory is one of recycling; that which came from the ground is being returned. If the safeguards that we have described are followed, it can be an economically and ecologically sound disposal method.

Another Interesting approach to solvbg this problem is the refeeding of the paunch contents. One of the contractors handling our paunch contents is mixing the paunch contents with ground cornstalks. The cornstalks are spread in 8 horizontal silo and paunch contents are spread with a spreader truck mer the top of the cornstalks. The mixture is then compacted into a horizontal silo. The paunch contents are ensiled 6 to 8 weeks prior to being utilized as animal feed. After one season of feeding the recycled material, the farmer was quite enthusiastic about the performance. He felt that it would also be possible to use low quality alfalfa hay or similar materials to provide the year round supply of additive material to the paunch contents.

Hair and Hide Trim

Although the hair and hide trim should not be considered as solid waste it is a solid generation that requires special handling. In our operations we combine hair, ears, face pieces and hide fleshings and process them in a wet cooker. The wet cooker is a vertical pressure tank capable of holding the production from approximately 500 head of cattle. The mterial is introduced to the wet cooker through a blow tank and the wet, cooker is pressurized with 90 psi steam for approximately 3 hours. After this period of time the material is blown out under pressure into a liquid receiving tank. In the liquid receiving tank, the oil phase is allowed to separate from the aqueous phase. The oil is taken off and sold as a separate product, fleshings oil. The aqueous phase has a high fat con-tent and a high protein content. It is pumped into our batch dry cookers after the dry cooker has been charged and the Fnternal temperature has reached appr~ximately230 degrees. 'Lhe wet cooking hydralizes the hair and produces a digestive protein when put into the dry cooker. This has proven to be an economical procees und In our estimation is probably the most desirable that we have come across.

Grease Skimmings

The grease skimming from the catch basin or air flotation units in our plants is wet cooked similar to the treatment of the hair and hide trinmings. The aqueous portion is returned to the sewer ahead of the skimming basin, since it has a low economic value. The grease fraction from the wet cooker is sold for animal feed at l#/lb discount from the inedible tallow production.

Paper and Packaging Waste

In our larger 2000 head a day plantu, we generate approximately 4000 pounds of miscellaneous packaging materials that must be dispmed of. We have found the most economics1 method to handle this waste is to contract with a private hauler.

The solid wastes generated in the meat packing operation can be disposed of in an acceptable manner. Improperly handled, it can result in an arroused public and extreme pressures from local, State and Federal authorities. The solid wastes can also nearly double the waste water strength if measures are not taken to isolate these materials at the point they are generated.

We have developed a method for land disposal of paunch contents that has proven successful for a period of four years for slaughter operations capable of 16,000 beef per week. Disposal of settling basin solids and flotation greases require different techniques but can be handled in an acceptable and economic method.

Prior to making such an installation in your facilities, we would invite you to inspect our Dakota City operation to obtain further details on the successful disposal of these materials. 1. Dry opening a paunch. 2. Paunch storage tank. 3. Truck and modified fertilizer spreader used to spread punch. 159 4. Loading truck with paunch manure. 160

5. Loading truck with paunch manure 161

6. Spreading paunch manure on growing corn. 162

J * D . FOX: Thank you, Mr. Franke, for telling us how to dispose of a. very perplexing problem. Ow: next speaker is not a stranger on this prrw,r*am. In fact, he presented a paper to this group only last year. Dr. J. C. Hesler received his B.S., M.S. and Ph.D. degrees from the TJniversity of Chicago. He has worked in the areas of water and waste treatment and organic resins synthesis since 1937. At present, he is manager, Corporate Environmental Control Department with Amour and Compmy. His responsibilities include problem resolution for air, water, solid wastes and noise pollution; liaiscm with local, state and federal agencies with respect to pollution problems; development cf nev waste control methods and new plant, new site acquisition evaluation with respect to pollution potentials and control requirements. It is with pleasure that I present Dr. J. C. Hesler.