Field of the Invention The present invention relates generally to the field of waste disposal and management. More particularly, the present invention relates to a system and method for creating compost from organic kitchen waste.

Background of the Invention It is well known today that an average family produces significant amounts of kitchen waste on a daily basis. This type of waste is mainly comprised of organic matter. Thus, when considered on an annual basis, there is a considerable amount of organic waste that must be disposed of in a safe and timely manner. Typically, such waste is disposed of in municipal landfills or incinerators. However, such disposal is often expensive as well as environmentally problematic. Thus, a need exists for disposing of residential organic kitchen waste in both a more economically and ecologically sound manner.

Disposing of organic waste by turning such waste into compost is well known in the art. However, due to the noxious odors associated with the decomposition of organic waste, simple compost piles are not favored. To increase the amount of aerobic decomposition, it is known in the art to aerate such piles using apparatus which vents air into the compost pile or by physically mixing the pile. However, such methods require complex apparatus or extensive labor and still fail to adequately eliminate the noxious odors. Thus, there exists a need for a composting method and apparatus to turn

organic waste into compost without the need for complex apparatus or extensive physical labor and that also adequately reduces the noxious odors associated with composting organic waste. Accordingly, it is a primary objective of this invention to provide a method of converting organic kitchen waste into an ecologically useable compost that requires minimal physical labor.

It is a further object of this invention to provide a system that is capable of sustaining an efficient composting process year round, inexpensively and without complex or moving parts.

It is a further object of this invention to provide a system and method for composting organic kitchen waste that substantially eliminates the odors associated with conventional composting.

Summary of the Invention The shortcomings of the prior art are overcome and the aforementioned objects are achieved in accordance with the principles of the present invention, by providing a novel self-emptying system and method for efficiently creating compost from organic waste without the need for mixing, moving parts or removing compost. Using the advanced biotechnology and superior construction of this invention, organic waste can be composted all year long in a rodent-proof, self-aerating, self- emptying, nearly odor free, top-loading enclosure.

The method of the present invention includes the steps of: providing a substantially upright self- emptying enclosure having a rodent-resistent perforated side wall; placing organic waste within said enclosure; introducing epigeic earthworms into said waste within said enclosure; and periodically

adding additional organic waste, whereby an active composting layer is maintained, rodents are excluded, compost is naturally discharged, and noxious odors are substantially reduced. The method further includes the steps of maintaining the composting substrate in a moist condition, and maintaining the mean temperature within the active composting layer between 35° - 95° F.

In another aspect, the method of the present invention includes the steps of: providing a substantially upright self-emptying enclosure having a perforated side wall; partially burying said enclosure; supplying a moist bedding within said enclosure; adding an initial amount of moist organic waste to said enclosure; aging said initial organic waste; adding epigeic earthworms to said aged organic waste wherein an active composting layer is formed; periodically adding moist organic waste on top of said active composting layer; and removing compost naturally expelled through said perforated side wall from the outer perimeter of said enclosure.

A system for practicing the principles of the present invention includes: a substantially upright self-emptying enclosure in which an active composting process is maintained, said enclosure having at least one perforated side wall; the side wall of the enclosure having numerous apertures preferably sized to maximize natural discharge of compost and aeration of the active composting layer and also to prevent pests from entering the enclosure. The side wall of said enclosure is preferably made of a gnaw-resistant material. The enclosure may also be provided with a protective strip fastened to the top edge, a removable top cover, a bedding layer, and an insulating blanket.

These and other features, aspects and advantages of the present invention will be more fully appreciated from the following detailed description when read in conjunction with the accompanying drawings.

Brief Description of the Drawings Figure 1 is an elevated side view of a perforated enclosure for efficient composting in accordance with the principles of the present invention.

Figure 2 is a side view of a perforated composting enclosure and cover of one embodiment of the present invention.

Figure 3 is a top view of the apparatus of figure 2 shown partially in phantom.

Figure 4 is an elevated side view of an insulated perforated composting enclosure constructed in accordance with the principles of the present invention.

Detailed Description

In accordance with the principles of the present invention, organic waste, such as residential kitchen waste, is composted through the use of a well- aerated, thin walled, durable, upright, perforated, gnaw-resistent, side wall enclosure in conjunction with earthworm biotechnology without turning or moving the composting substrate or needing to remove the compost from the enclosure by any mechanical means for its continued use. The system has no moving parts, nor does it need to be turned for any reason. Epigeic earthworms, such as eisenia fetida , are used synergistically with indigenous microbes to enhance the degradation of the composting substrate.

The enclosure (10) , as shown in figure 1, is designed to sustain the composting process by jointly addressing the problems of aeration, cooling, compost recovery, drainage, scavenging, and protection of the earthworm population. There are numerous configurations of the enclosure (10) that satisfy the requirements of the present invention, although the side walls (12) of the enclosure (10) should be substantially upright. Preferably, the enclosure (10) will be regularly shaped in plan area with vertical sides. However, other irregular plan shapes, e.g. serpentine, and enclosures with non- vertical sides such as those in a truncated inverted cone, may be suitable as well. The enclosure (10) typically has a height of from two to four feet and a horizontal cross-sectional area of from two to twelve square feet. However, enclosures of other dimensions may also be utilized to practice the principles of the present invention. In order to aerate the organic matter within the enclosure (10) , the side walls (12) of the enclosure (10) have numerous openings or apertures (14) . Preferably, the side walls (12) have a maximum surface area of openings (14) so as to maximize self- voiding of compost, drainage, convective aeration and cooling of the substrate. However, openings (14) should be small enough to prevent pests or rodents such as mice, moles, or similar pests from entering the enclosure (10) and disrupting the composting system. The side walls (12) of the enclosure (10) are formed of a durable material capable of resisting gnawing by such pests. Although any sufficiently durable material will suffice, an example of such material is galvanized hardware cloth.

The bottom (18) of the enclosure (10) should be free draining. The bottom can be made of material similar to that of the side walls (12) , although, depending on the material utilized it may need to be more rigid and/or have openings which make up a smaller percentage of the surface area. Alternatively, the bottom (18) of the enclosure (10) may comprise in situ soil material. However, when in situ soil is utilized as the enclosure bottom, it is preferred that the side walls (12) of the enclosure (10) be sufficiently buried below ground level (20) to prevent vermin and pests from crawling or burrowing into the enclosure (10) . Typically, burying the side walls (12) of the enclosure about six to nine inches deep will prevent such intrusion. As depicted in Figs. 2 and 3, a cover (22) is preferably employed on the top open end of enclosure (10) . The cover (22) should allow for infiltration of natural rainfall and periodic addition of organic waste into the inner portion of the enclosure (10) . In addition, the top cover (22) should not prevent good air circulation over the top of the composting substrate within the enclosure (10) . The cover (22) may be made of the same material as the side walls (12) . However, the cover (22) may also be comprised of perforated solid materials. For example, a simple but adequate cover can be formed from one or two pieces of perforated plywood placed on the top of the enclosure (10) with several weighted objects, such as bricks (not shown) , used to keep pests from removing the cover (22) and entering the enclosure (10) . Preferably the perforations within the cover (23) are frequent, uniformly distributed, and large enough to ensure infiltration of rainfall. The cover may take many other forms as well.

A rigid protective strip or hoop (16) may optionally be placed over or fastened to the top edge of the side walls (12) of enclosure (10) . This will help prevent the enclosure from becoming deformed as well as prevent accidental cuts or scrapes when materials such as galvanized mesh is utilized to make the side walls (12) .

An additional optional element of the composting system of the present invention is an insulating blanket (26) as shown in figure 4. The insulating blanket (26) should be sufficient to keep the material within the enclosure (10) from freezing but not substantially restrict aeration of the enclosure (10) . In one embodiment, a second outer enclosure (28) , formed, e.g. of chicken wire, surrounds the side walls (12) and is located several inches therefrom. An insulating material, ^" e.g. dry leaves, may then be placed in the space between the two enclosures and on top of the material within the enclosure. Such an insulating blanket containing a 4-inch thickness of dry leaves has been found to be adequate for the winters commonly experienced in Syracuse, New York.

It is presently preferred to use a circular enclosure made from 0.5 inch mesh, galvanized hardware cloth which is commercially available in widths of 36 inches and a wire gauge of about 0.045 inches. The enclosure is constructed by first creating a hoop with a diameter of about 30 inches from an eight-foot length of the hardware cloth.

After the two loose ends of the length are fastened together (by overlapping and sewing with compatible cord or using other suitable fasteners) , the resulting hoop is placed in an upright position on level ground and a line is scribed on the ground to

demark the circumference of the eventual cylindrical enclosure. Next, the soil is dug out along the scribed line to a depth of 6 to 9 inches so the hoop can be easily placed in the resulting circular trench while maintaining a nearly perfect circular shape and level top edge. With the hoop so placed, the soil is uniformly and carefully replaced and compacted in the trench to provide solid support for the partially buried, upright enclosure. Next, a rigid, ring- shaped hoop is fastened to the entire top edge of the enclosure to prevent accidental deformation of the top edge. The enclosure is now ready for operation, although a simple cover made from two pieces of perforated plywood (one of which is larger and pivots on top of the other for ease of opening) will be helpful. Moreover, a weight of perhaps 20 pounds (such as several bricks) placed on top of the pivoting piece of the cover will be helpful in keeping animals out. The first step of the composting method of the present invention is to provide an enclosure as described hereinabove capable of sustaining the composting process. The enclosure should be placed on ground that is substantially level or a platform. If it is to be placed on the ground, the enclosure should be partially buried as discussed above to prevent pests and other animals from entering the composting system. The enclosure should be located outside away from areas receiving significant recreational or industrial use to minimize the potential for damaging the enclosure. It should also be set in a location that is well drained and open to any existing air currents. In addition, if the composting system is set up in a climate which commonly experiences periods of high temperatures

above 75°F, it is preferable to locate the enclosure in a shaded area.

Once the enclosure is erected, the next step is to add organic waste to the interior portion of the enclosure. Almost any organic waste capable of rapid aerobic decomposition by microorganisms can be decomposed to form compost utilizing the method and system of this invention. For example, most residential organic kitchen waste such as fresh, cooked or rotting food, such as fruits, vegetables, meat, poultry, eggshells, dairy products, and moist paper products, etc. may be utilized and turned into compost. Preferably large pieces of waste are cut up in order to improve aeration and increase the amount of surface area available for decomposition by the microorganisms. Although processed foods that are overly salty (such as ham or brine) or overly acidic (such as vinegar or mayonnaise) may be composted utilizing this method, it is preferable that large amounts of such materials not be added all at one time. In addition, it is preferable not to utilize significant amounts of these materials to start up the composting system. Material such as coffee filters, coffee grounds, paper plates and other paper products may also be decomposed and composted pursuant to the present invention. However, paper plates should also not be added in large amounts or utilized in the start-up of the composting process. To start up the composting process, the first organic waste added to the enclosure should not be a substantial amount. Typically, the waste that is accumulated by a 4-person family in one or two weeks would be a good amount of organic waste to start up the composting system. It is further preferred that the organic waste used to start up the composting

system be aged to ensure that a large number of microorganisms exist for the epigeic earthworms to feed upon when added to the system. The waste may be aged by maintaining the waste in the enclosure for one to two weeks and by periodically turning the waste. Prior to addition of the earthworms, the organic waste should be spread evenly over the bottom of the composting enclosure.

The next step is to place the epigeic earthworms onto the organic waste. An example of an epigeic earthworm is the eisenia fetida which is commonly referred to as either the red wiggler, redworm or manure worm. Such worms are near surface feeders and may sometimes be found in areas with a large amount of organic matter such as on farms with old manure piles. These worms are also commercially available from the Carter Worm Farm in Plains, Georgia, as well as other supply houses throughout the United States. As the organic waste decomposes, these earthworms burrow through the organic waste selectively feeding on decaying microorganisms that produce foul odors. In doing so, they also (1) consume rotting portions of the substrate; (2) produce a dark brown, biologically-stable casting (hereinafter called compost) ; (3) mix and turn the waste as they move along, creating tunnels which in turn promote a cooler, oxygen-rich microenvironment; (4) reduce the localized oxygen demand created by decaying microbes; and (5) create fresher surfaces within the substrate for attack by the healthy microbes, all of which has the effect of promoting faster and more complete composting without the need to turn the substrate which is common to conventional composting systems.

The worms in combination with the microorganisms act to decompose the organic waste into compost. The

eisenia fetida are primarily near-surface feeders and will be most active near the surface of the materials within the enclosure (10) . Thus, an active composting layer will generally remain within the upper portion of the organic material. Underneath the active composting, layer remains wet compost which will naturally flow out through the apertures (14) in the.upright side walls (12) to the outside of the enclosure (10) and may be easily removed without disturbing the composting system. This compost may be used as soil for gardens, lawns or potted plants. Only a small supply of earthworms are needed to begin. Generally, from 250 - 500 earthworms will suffice, depending on the amount of waste to be composted. As the waste accumulates and decays, the microbial and earthworm populations will expand to ensure a relatively nuisance-free system. The compost naturally flows to the sides and is expelled from the enclosure through the apertures by a combination of earthworm activity and gravity. The self-voiding of the compost enclosure is also enhanced as the bottom layer increases in depth. In addition, keeping the edges of the composting layer moist will encourage the presence of earthworms near the perimeter of the enclosure and further increase voiding of compost. The combined effect of the continuing expelling and substrate degradation is to obviate the need to empty the enclosure by mechanical means for several years. Hence, the composting system is self-operating following activation except for (1) routine addition of organic waste; and possibly (2) maintaining an appropriate moisture content; and (3) maintaining a safe average temperature.

After the earthworms have been added to the aged organic waste, additional moist organic kitchen waste should periodically be added. No mixing or turning of the waste within the self-voiding enclosure is required and the additional organic material should be added to the top of the existing substrate. It is preferred that the additional organic waste be added on a regular basis in small amounts. When new organic material is added, it is preferably evenly spread across the top layer. The earthworms require a continuous food supply and, therefore, additional organic waste should not be added so infrequently that the previous waste has been substantially decomposed. An additional step to the composting process may include adjusting the moisture content of the active composting layer. The contents of this layer should be kept thoroughly moist, although not so saturated that the substrate is dense, prevents aeration or is harmful to the synergistic organisms. The worms breathe through their moist skin and insufficient moisture will be damaging to the worms.

As shown in figures 2 and 3, one method for controlling the moisture content of the active composting layer is by utilizing a perforated cover (22) on the top open end of the enclosure (10) . The cover (22) should allow for entry of natural precipitation, yet substantially prevent intense sunlight from striking the surface materials within the enclosure. However, the cover should also be removable or capable of being, opened so as to allow for periodic addition of organic waste within the enclosure (10) . An example of an adequate cover would be two pieces of perforated plywood placed on top of the self-voiding enclosure (10) .

If the weather conditions are hot and dry, it may be necessary to add water to the substrate within the enclosure to ensure that the composting materials remain thoroughly moist. Furthermore, to promote voiding of the compost, the perimeter of the substrate within the enclosure should also kept thoroughly moist. It is preferable to add the water by a sprinkling means rather than pouring water directly onto the substrate. Similarly, depending upon the climate, it may be necessary to maintain an appropriate temperature within the active composting layer. The composting process and the.health of the earthworms dictate the acceptable temperature ranges in which the composting system will function. When using eisenia fetida it is important that the temperature of the active composting layer be maintained within a range of 35° - 95° Fahrenheit, or approximately 2° - 35° Celsius. It is not necessary that the temperature within some portions of the active composting layer never exceed this range but that the temperature should not be allowed to remain outside of this range for more than a few days, during which period the earthworms will often temporarily relocate to warmer or cooler areas. It should be noted that the composting process itself generates heat and, therefore, the temperature of the active composting layer may exceed 95° Fahrenheit even when the outside temperature remains below that mark. The simplest way to prevent overheating is to avoid introducing large amounts of fresh, green organic waste (such as corn shucks) all at one time and by limiting the depth of the active composting layer. Frequently adding small amounts of waste will reduce the amount of heat generated and maintained within the composting system. In

addition, to help prevent overheating, the composting system may be placed in the shade or have a cover placed upon the open top as discussed above to reduce the amount of direct sunlight on the composting layer.

Under colder conditions such as in the winter months, it may be necessary to insulate the composting system. One method for doing that is by placing an insulating blanket, as discussed hereinabove, around the outside of the self-voiding enclosure (10) . During the winter months, if a warm spell is experienced, it should not be necessary to remove the entire insulating blanket since simply removing the insulation on top of the composting material during the warm period may be enough to control overheating. In addition, it is important that the insulating blanket is neither so dense nor so impervious that it acts to cut off the aeration or drainage of the composting substrate. Depending on the climate and the time of year in which the composting process is first practiced, it may be necessary to add a layer of bedding to the floor of the enclosure prior to adding organic waste. It is preferred that such a bedding be utilized prior to starting up a composting process regardless of the climate. Nevertheless, the bedding may not be necessary if the process is initiated in the spring or summer of moderate climates. However, it is necessary to utilize a bedding when starting up the composting process if the mean daily temperature will not be above 40° Fahrenheit for the next month.

The bedding may comprise a collection of moist mature compost, shredded cardboard, or leaf mold. Fresh grass clippings should be avoided as either bedding material or organic waste. If the present

invention is initiated during the spring or summer months in moderate climates, then a few inches of wet leaves or like material will suffice as bedding. Due to the natural variations in climate, there can be no absolute assurance that a system installed and activated in the fall or winter in cooler climates will not freeze. However, when the process is initiated in the fall or winter in cooler climates, a heavier bedding consisting of an equal mixture of sphagnum peat moss and aged horse or cow manure approximately 8 inches thick should be utilized to help prevent the same. The material should be moist but should not be so moist that it is dense and restricts airflow. By practicing the principles of the present invention one may efficiently create compost from organic kitchen waste without requiring mixing of the organic substrate or removal of the compost by mechanical means. The principles of the present invention, utilizing the action of the epigeic earthworms, indigenous microbes and a self-voiding enclosure, are combined to create a faster, nuisance- free, less odorous and virtually self-sustaining composting system. Although the invention has been disclosed in relation to the embodiments described„herein, it is apparent that various modifications, substitutions, equivalents and other changes may be made without departing from the spirit of the invention. Any such modifications are intended to be within the scope of the invention as defined by the following claims.