Classifications

• • C—CHEMISTRY; METALLURGY
  • C05—FERTILISERS; MANUFACTURE THEREOF
  • C05F—ORGANIC FERTILISERS NOT COVERED BY SUBCLASSES C05B, C05C, e.g. FERTILISERS FROM WASTE OR REFUSE
  • C05F3/00—Fertilisers from human or animal excrements, e.g. manure
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
  • Y02A40/00—Adaptation technologies in agriculture, forestry, livestock or agroalimentary production
  • Y02A40/10—Adaptation technologies in agriculture, forestry, livestock or agroalimentary production in agriculture
  • Y02A40/20—Fertilizers of biological origin, e.g. guano or fertilizers made from animal corpses
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
  • Y02P20/00—Technologies relating to chemical industry
  • Y02P20/141—Feedstock
  • Y02P20/145—Feedstock the feedstock being materials of biological origin

Definitions

• TITLE METHOD OF STABILIZING ODORS IN MANURE
• Liquid- solid separation systems include settling tanks, basins, channels, mechanical separation systems, evaporation ponds and dehydrators.
• Liquid manure storage systems utilize manure pits, earthen storage basins (i.e., lagoons), and aboveground tanks.
• a further object of this invention is to provide a process of stabilizing odors in manure which will be effective in treating the manure in a large variety of collection devices.
• a still further object of this invention is to provide a method of stabilizing odors in manure which is effective in manures of differing composition.
• a still further object of this invention j s to provide a method of stabilizing odors in manure which will preserve the fertilizer potential of the manure.
• a still further object of this invention is to provide a method of stabilizing odors in manure which is economical and cost-effective.
• a still further object of this invention is to provide a method of stabilizing odors in manure which will be environmentally acceptable.
• This invention involves the method of adding lime, fly ash, cement kiln dust or the like, or mixtures thereof, with manure comprised of liquid and solids in sufficient quantity to raise the pH thereof to a minimum of 7, a maximum level of 10.5, and an optimum of 9.5 to minimize the release of ammonia, hydrogen sulfide, and other odor producing elements from the manure.
• Fig. 1 is a bar graph showing the change in odor threshold versus time after start up for three levels of alkaline addition versus an untreated control.
• the levels of treatment were 5 lb, 2.5 lb, and 1.25 lb additive added per 1 lb of solids in the manure;
• Fig. 2 is a bar graph showing the change in pH of treated manure versus time after start up for three levels of alkaline addition versus an untreated control.
• the levels of treatment were 5 lb, 2.5 lb, and 1.25 lb additive added per 1 lb of solids in the manure;
• Fig. 3 is a bar graph showing the change in ammonia levels of the headspace of a manure storage tank versus time after start up for three levels of alkaline addition versus an untreated control.
• the levels of treatment were 5 lb, 2.5 lb, and 1.25 lb additive added per 1 lb of solids in the manure;
• Fig. 4 is a bar graph showing the pH values of five treated samples of manure compared to the untreated control sample with 0.25 lbs of additive added per 1 lb of solids in the manure;
• Fig. 5 is a bar graph showing the pH values of five treated samples of manure compared to the untreated control sample with 0.5 lbs of additive added per 1 lb of solids in the manure;
• Fig. 6 is a bar graph showing the odor intensity values of five treated samples of manure compared to the untreated control sample with 0.25 lbs of additive added per 1 lb of solids in the manure?
• Fig. 7 is a bar graph showing the odor intensity values of five treated samples of manure compared to the untreated control sample with 0.5 lbs of additive added per 1 lb of solids in the manure;
• Fig. 8 is an elevational view of one of the laboratory test apparatus used to determine the utility of this invention.
• Fig. 9 is a bar graph showing the odor threshold from the liquid surface of treated samples compared to an untreated sample as contained in earthen storage at various times of the year;
• Fig. 10 is a bar graph showing the change in odor threshold from the liquid surface of treated samples contained in concrete storage versus time.
• the purpose of this invention is to add sufficient materials, primarily alkaline materials, to manure, comprised of both liquid and solids, to raise the pH thereof to an optimum level of 9.5 which will minimize the release of ammonia and hydrogen sulfide and other odor producing gases.
• the materials to be used as the additive to the manure are lime, kiln dust, fly ash, or derivatives thereof, including mixtures of these ingredients and other materials derived from calcining processes, combustion by-products and powdered adsorbents containing activated carbon and/or dry clay.
• the major constituents of cement kiln dust and fly ashes are oxides of calcium, silica, aluminum, and sulfur.
• the process of this invention can be conducted wherever the animal manure is collected. However, manures collected in pits, holding tanks or earthen basins are most convenient for implementation of the process. While the process is useful for the treatment of any type of waste, it is particularly suitable for the treatment of animal wastes, especially in animal and poultry confinement operations.
• animal wastes as used herein will be understood to include poultry manure as well as animal manure.
• the principal thrust of this invention is to treat the animal wastes so as to settle the solids in the manure with respect to the liquid portion thereof, and to adjust the pH of the manure, and particularly the liquid portion thereof to a level that will minimize the release of the odorous compounds from the manure. Specifically, the pH is adjusted to an optimum level of 9.5 which will minimize the release of both ammonia and hydrogen sulfide which are two of the principal odor causing factors. This technique also is believed to suppress the release of other odor causing compounds. By suppressing the release of ammonia, the use of the treated manure as fertilizer is substantially enhanced.
• the admixture used for increasing the pH of manure in its natural state is usually, but not always, an alkaline material comprised of one or more of lime, kiln dust or fly ash, or derivatives thereof. Kiln dust and fly ash are plentiful and generally less expensive than lime.
• the admixtures are preferably added to the manure at the rate of 0.2 to 1 lb of admixtures to 1 lb of manure, respectively, by dry weight of solids. They can be added by special equipment as described in the Field Test set forth hereafter, or through any convenient material handling system.
• the admixture is added periodically to the manure to maintain the pH thereof within the above defined range. Thorough agitation of the mixture of manure and additives to provide a homogenous mixture is required in all applications. Under some conditions, daily applications may be necessary. Daily checking of pH values is not necessary, but may be required if problems are encountered.
• Swine manure storage facilities are the major potential odor sources from swine operations. Alkaline treatment of manure can help reduce odors from the manure storage and during land application. When the waste is collected and stored, it undergoes decomposition due to the metabolic actions of microorganisms. The manure gases of odor concern are ammonia, hydrogen sulfide, and volatile odorous compounds. EXAMPLE 1 Pilot Study
• the initial rates of CKD to manure on a dry weight basis were 2.3 lb to 1 lb, and 0.5 lb to 1 lb.
• the manure used in the field test had an actual solids content of 0.8 percent. Adjusted addition rates based on the actual solids content were 5 lb, 2.5 lb and 1.25 lb additive to 1 lb manure solids.
• Odor threshold is the ratio of the number of volumes of fresh air required to mix with one volume of odorous air so that the odor can hardly be detected.
• CKD addition to manure provided significant odor reduction during the mixing, storage and final land application of the manure used in this field test.
• the manure used in all four treatments was agitated thoroughly just prior to air quality sample collection on day 36 of the trial. Analysis of the final sample showed an odor threshold of 1250 for the untreated control compared to 59,107, and 362 for treatments 1, 2 and 3, respectively. Detectable odor levels were effectively reduced by 95 percent, 91 percent, and 71 percent at the three treatment levels compared to the untreated control.
• the treated manure in the pilot test was agitated and field applied on day 42 of the trial. Air samples were taken from the application sites and analyzed for odor thresholds. Low odor thresholds (less than 8) were found for all treatments. It was determined that the addition of the CKD material caused the solids in the liquid manure to settle. This settling phenomenon is very important because it allows a watercap to form over the settled solids. This watercap provides a physical barrier between the odorous solid material and the atmosphere. The watercap also minimizes the oxygen content in the solid material which effectively inhibits the bacterial activity in the solids which in part is responsible for generation of odorous gases. The CKD also increases the pH level of the liquid existing above the solids to optimum pH levels of 9.5 which suppresses the production of hydrogen sulfide gas and aids in minimizing the release of ammonia as well as other odor producing gases.
• the laboratory study used five different alkaline byproducts including combustion residues (fly ashes), lime kiln dusts and cement kiln dusts. Calcium oxide was a major oxide component in each of the alkaline byproducts used.
• the manure for the experiment was from an 1100 head swine finishing building. The manure was collected from a small pit at the end of the building into which the manure was scraped as needed, generally, twice daily. The manure was agitated prior to collection for treatment in the laboratory.
• Each column was sealed and one-half cubic feet per minute of air was continuously pumped into the column headspace and exhausted to the outside.
• the air in the room surrounding the tanks was maintained between 65 to 70 degrees Fahrenheit.
• Figures 4 and 5 show the change of pH with time for each product. As the treatment level went from 0.25 lb to 0.5 lb of product per lb of solids in the manure, the pH increased.
• the manure without treatment (6) had the lowest pH of approximately 7.0.
• the pH basically increased to the highest level at day 10 and decreased back to a slightly lower level at day 21 for the 0.25 lb of additive per lb of solids in the manure.
• Figure 5 shows the pH was between 8.5 to 9.2 for the products at a level of 0.5 lb of additive per lb of solids in the manure.
• the pH remained almost constant throughout the total test period.
• the ammonia levels in the headspace of the columns were higher than the control in all cases. It can be observed that the pH at the lower level of additive resulted in 2 to 5 times higher ammonia level than the control.
• the higher level of product resulted in 4 to 17 times higher ammonia level.
• Table 2 shows more variability within each product level than between the levels of product added. The control is also in the middle of the range in all chemicals evaluated. The chemical analysis for two of the 0.25 lb products added per 1 lb of manure solids was not analyzed.
• 6A is the control IB to 5B is at the 0.5 LB additive in the same order as the product numbers
• N(A) (ammonia nitrogen) NOx (nitrate-nitrite)
• This production facility was equipped with an under-slat scraping system and an earthen manure storage basin.
• the equipment utilized in the process was installed at the site in the spring of 1995.
• the equipment included a 4 ton silo for alkaline byproduct storage, a volumetric metering device with electronic programmable controller, a 3,000 gallon manure mixing tank, and an agitator pump to mix the product in the manure and to pump the treated manure into the earthen basin.
• the building was scraped twice daily and the manure gravity flowed from the swine building to the 3,000 gallon buried concrete mixing tank.
• the operator measured the depth of the manure in the tank and entered the mass of the alkaline byproduct into the controller based upon the manure volume. The remainder of the processing of the material was automatic based upon preset parameters.
• the mixing pump was set to operate for 3 minutes after the material was augered into the underground manure tank and then the treated manure was pumped into the earthen basin.
• the alkaline byproduct utilized in the field study was the product 4 analyzed in the laboratory study. Initial addition rate of alkaline byproduct was .25 lb to 1 lb of dry manure solids. When the project was initiated, it was estimated that the earthen basin contained approximately 240,000 gallons of manure.
• Alkaline byproduct (see above) was added to the basin on June 7, 1995 by complete agitation of the basin through the 3,000 gallon mixing tank to bring the ratio of alkaline byproduct to manure solids in the earthen basin to the desired treatment level.
• the production facility utilized as the untreated control was selected as it was similar to the treated facility.
• the age, gender, and genetics of the hogs and the feeding rations used at both facilities were close to identical.
• the control facility was located within 20 miles of the treated facility.
• the control unit had significantly higher odor levels than the treated unit.
• the normal flow of material added on a day to day basis was at the rate of 0.3 lb per lb of solids.
• the solids was based upon 4 percent solids to account for using spray water for cooling the pigs during warm weather.
• the gases produced from the surface of the earthen basin were evaluated for odor, ammonia, and hydrogen sulfide. Liquid samples were taken and similar analysis to the laboratory study was made. Downwind odor evaluation at the road was measured with a scentometer. The odor level was significantly lower when standing on the downwind side of the earthen basin with treatment.
• the graph in Figure 9 shows that the odor was approximately 55 to 60 percent less in the treated slurry than in the control.
• the odor level on September 10 is shown to be as strong as on the control, but lower than typical for the control unit. It was observed that a change in weather accompanied that particular day. The same observation was made on another day of similar climatic conditions; however the odor level was not as strong as on the control slurry basin. The odor downwind was significantly affected by the treatment of the slurry. Often times, the odor from the treated manure could not be detected at a distance of 500 feet from the basin.
• the odor level can be significantly reduced by using alkaline byproducts at the levels tested.
• the odor level was significantly lower when standing on the downwind side of the concrete basin.
• the graph indicates that the odor was approximately 90-95% less in the treated slurry compared to the raw manure.
• the downwind observations during the field application reflected the same results as in the storage basin.
• the process of this invention will permit manure comprised of liquid and solids to have the odors thereof substantially stabilized through the adjustment of the pH of the manure to a level of approximately 7.5 to 9.5 wherein the release of the principal odor producing gases hydrogen sulfide and ammonia will be substantially minimized along with other odor producing gases which release at pH levels beyond this range.
• This invention therefore will achieve at least its stated objectives.

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• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Treatment Of Sludge (AREA)
• Fertilizers (AREA)

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• 1996
  • 1996-12-13 WO PCT/US1996/020453 patent/WO1997021647A1/en not_active Application Discontinuation
  • 1996-12-13 EP EP96945253A patent/EP0809615A1/de not_active Withdrawn
  • 1996-12-13 AU AU14668/97A patent/AU1466897A/en not_active Abandoned
  • 1996-12-13 CA CA002212987A patent/CA2212987A1/en not_active Abandoned

Non-Patent Citations (1)

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