Characteristics of dairy manure composting with rice straw

The aim of this work was to investigate the effects of aeration rate, aeration method, moisture content, and manure age on the characteristics of dairy manure composting with rice straw in terms of composting temperature, oxygen consumption rate, emission of odorous gases, and final compost property. It was found that the aeration rate of 0.25 L/min-kg VS was capable of achieving the highest composting temperature, longest retention time of high temperature, and less emission of odor gases. Except for the composting temperature reached, there was no significant difference between bottom-forced and top-diffusion aerations in terms of final compost property. The higher initial moisture content (65%) was more favorable for its higher temperature, longer retention time of high temperature, and more stable end compost obtained. Fresh manure showed better composting performance than the aged manure for its higher temperature reached in less time and less ammonia emission. Oxygen consumption rates were basically similar to those of temperatures. Most emissions of the odorous gases occurred during the first week of composting, therefore, special attention should be paid to this period of time for effective odor control.     

Species Diversity and Substrate Utilization Patterns of Thermophilic Bacterial Communities in Hot Aerobic Poultry and Cattle Manure Composts

This study investigated the species diversity and substrate utilization patterns of culturable thermophilic bacterial communities in hot aerobic poultry and cattle manure composts by coupling 16S rDNA analysis with Biolog data. Based on the phylogenetic relationships of 16S rDNA sequences, 34 thermophilic (grown at 60 degrees C) bacteria isolated during aerobic composting of poultry manure and cattle manure were classified as Bacillus licheniformis, B. atrophaeus, Geobacillus stearothermophilus, G. thermodenitrificans, Brevibacillus thermoruber, Ureibacillus terrenus, U. thermosphaericus, and Paenibacillus cookii. In this study, B. atrophaeus, Br. thermoruber, and P. cookii were recorded for the first time in hot compost. Physiological profiles of these bacteria, obtained from the Biolog Gram-positive (GP) microplate system, were subjected to principal component analysis (PCA). All isolates were categorized into eight different PCA groups based on their substrate utilization patterns. The bacterial community from poultry manure compost comprised more divergent species (21 isolates, seven species) and utilized more diverse substrates (eight PCA groups) than that from cattle manure compost (13 isolates, five species, and four PCA groups). Many thermophilic bacteria isolated in this study could use a variety of carboxylic acids. Isolate B110 (from poultry manure compost), which is 97.6% similar to U. terrenus in its 16S rDNA sequence, possesses particularly high activity in utilizing a broad spectrum of substrates. This isolate may have potential applications in industry.     

Community structure and population dynamics of ammonia oxidizers in composting processes of ammonia-rich livestock waste

This study investigated the relationship between the population dynamics of ammonia-oxidizing bacteria (AOB) and archaea (AOA), and changes in the concentrations of nitrogenous compounds during ammonia-rich livestock waste-composting processes. The data showed that ammonia in beef and dairy cow livestock waste-composting piles was slowly oxidized to nitrite and nitrate after approximately 21–35 days under thermophilic or moderately thermophilic and mesophilic conditions. Real-time quantitative PCR (qPCR) assays showed a relative abundance of betaproteobacterial AOB during ammonia oxidation but did not detect AOA in any composting stage. Furthermore, real-time qPCR and terminal-restriction fragment length polymorphism (T-RFLP) analyses for the AOB in two composting processes (beef and dairy cow livestock waste) out of the three studied found that thermophilic or moderately thermophilic uncultured betaproteobacterial AOB from the “compost AOB cluster” contributed to ammonia oxidation during hot composting stages. Non-metric multidimensional scaling analyses of the data from T-RFLP showed that only a few analogous species predominated during composting of beef, dairy cow and pig livestock wastes, and thus, the AOB community structures in the three composting piles operating under different conditions were similar. AOB-targeted clone library analyses revealed that uncultured members of the “compost AOB cluster”, which could be clearly distinguished from the authentic species of the genus Nitrosomonas, were the major constituents of the AOB populations. These results suggested that a limited and unique species of AOB played a role in ammonia oxidation during the composting of ammonia-rich livestock waste.     

Persistence of Mycobacterium avium subsp. paratuberculosis and other zoonotic pathogens during simulated composting, manure packing, and liquid storage of dairy manure

Livestock manures contain numerous microorganisms which can infect humans and/or animals, such as Escherichia coli O157:H7, Listeria monocytogenes, Salmonella spp., and Mycobacterium avium subsp. paratuberculosis (Mycobacterium paratuberculosis). The effects of commonly used manure treatments on the persistence of these pathogens have rarely been compared. The objective of this study was to compare the persistence of artificially inoculated M. paratuberculosis, as well as other naturally occurring pathogens, during the treatment of dairy manure under conditions that simulate three commonly used manure management methods: thermophilic composting at 55 degrees C, manure packing at 25 degrees C (or low-temperature composting), and liquid lagoon storage. Straw and sawdust amendments used for composting and packing were also compared. Manure was obtained from a large Ohio free-stall dairy herd and was inoculated with M. paratuberculosis at 10(6) CFU/g in the final mixes. For compost and pack treatments, this manure was amended with sawdust or straw to provide an optimal moisture content (60%) for composting for 56 days. To simulate liquid storage, water was added to the manure (to simulate liquid flushing and storage) and the slurry was placed in triplicate covered 4-liter Erlenmeyer flasks, incubated under ambient conditions for 175 days. The treatments were sampled on days 0, 3, 7, 14, 28, and 56 for the detection of pathogens. The persistence of M. paratuberculosis was also assessed by a PCR hybridization assay. After 56 days of composting, from 45 to 60% of the carbon in the compost treatments was converted to CO2, while no significant change in carbon content was observed in the liquid slurry. Escherichia coli, Salmonella, and Listeria were all detected in the manure and all of the treatments on day 0. After 3 days of composting at 55 degrees C, none of these organisms were detectable. In liquid manure and pack treatments, some of these microorganisms were detectable up to 28 days. M. paratuberculosis was detected by standard culture only on day 0 in all the treatments, but was undetectable in any treatment at 3 and 7 days. On days 14, 28, and 56, M. paratuberculosis was detected in the liquid storage treatment but remained undetectable in the compost and pack treatments. However, M. paratuberculosis DNA was detectable through day 56 in all treatments and up to day 175 in liquid storage treatments. Taken together, the results indicate that high-temperature composting is more effective than pack storage or liquid storage of manure in reducing these pathogens in dairy manure. Therefore, thermophilic composting is recommended for treatment of manures destined for pathogen-sensitive environments such as those for vegetable production, residential gardening, or application to rapidly draining fields.     

Effect of compost temperature on oxygen uptake rate, specific growth rate and enzymatic activity of microorganisms in dairy cattle manure

Investigations were carried out to find out the relationship between temperature and microbial activity in dairy cattle manure composting using oxygen uptake rate, specific growth rate and enzymatic activities during autothermal and isothermal composting experiments. In autothermal composting, oxygen uptake rate and specific growth rate were found to be most intensive in order of 43 degrees C, 60 degrees C and 54 degrees C. Isothermal composting at 54 degrees C resulted highest levels of enzymatic activity and promoted the volatile solids reduction. Based on the maximum enzymatic activity, specific growth rate appeared to be more closely linked with microbial activity in compost than with oxygen uptake rate. The enhancement of specific growth rate, enzymatic activity and volatile solids reduction were induced at 54 degrees C in cattle manure composting.     

畜禽粪便堆肥过程中各种氮化合物的动态变化及腐熟度评价指标

对不同畜禽粪便在堆肥过程中各种含氮化合物的动态变化进行了研究,结合综合性腐熟度评价指标——种子发芽指数（GI）,探讨了畜禽粪便堆肥过程中与氮有关的腐熟度评价指标.结果表明：随着堆肥的进行,除奶牛粪外,其它畜禽粪便的全氮（TN）含量均呈先下降而后平稳变化趋势,奶牛粪则呈先增加而后平稳变化趋势;各种畜禽粪便中,碱解性氮（HN）含量先增后降;NH₄⁺-N含量先下降而后保持平稳;NO₃^- -N含量则持续增加;NH₄⁺ -N/NO₃^- -N迅速降低.堆肥腐熟度指标中,除综合性评价指标GI值外,HN/TN和NH₄⁺ -N/TN也可作为评价畜禽粪便腐熟程度的优选指标,而NO₃^- -N/TN只能作为一般性评价指标.根据综合性评价指标GI值达到腐熟要求的标准（GI>0.50）,除仔猪粪外,其它畜禽粪便在HN/TN<20.77％、NH₄⁺ -N/TN<10.06％及NO₃^- -N/TN>0.38％时基本达到腐熟要求.     

Effect of high compost temperature on enzymatic activity and species diversity of culturable bacteria in cattle manure compost

To clarify the characteristics of thermophilic bacteria in cattle manure compost, enzymatic activity and species diversity of cultivated bacteria were investigated at 54, 60, 63, 66 and 70 degrees C, which were dependent on composting temperature. The highest level of thermophilic bacterial activity was observed at 54 degrees C. Following an increase in temperature to 63 degrees C, a reduction in bacterial diversity was observed. At 66 degrees C, bacterial diversity increased again, and diverse bacteria including Thermus spp. and thermophilic Bacillus spp. appeared to adapt to the higher temperature. At 70 degrees C, bacterial activity measured as superoxide dismutase and catalase activity was significantly higher than at 66 degrees C. However, the decomposition rate of protein in the compost was lower than the rate at 66 degrees C due to the higher compost temperature.     

Co-Composting of Soil Heavily Contaminated with Creosote with Cattle Manure and Vegetable Waste for the Bioremediation of Creosote–Contaminated Soil

Mispah form (FAO: Lithosol) soil contaminated with >380 000 mg kg^?1 creosote was co-composted with cattle manure and mixed vegetable waste for 19 months. The soil was mixed with wood chips to improve aeration and then mixed with cattle manure or mixed vegetable waste in a ratio of 4:1. Moisture, temperature, pH, ash content, C:N ratios, and the concentrations of creosote in the compost systems were monitored monthly. The concentrations of selected hydrocarbons in the compost systems were determined at the end of composting. Temperature rose to about 45°C in the cattle manure compost within two months of incubation while temperature in the control and vegetable waste remained below 30°C until the fourth month. Creosote concentration was reduced by 17% in the control and by more than 99% in the cattle manure and vegetable waste compost after composting. The rate of reduction in concentration in the mixed vegetable waste compost was initially lower than in the cattle manure compost. The reduction rate became similar in later months with only small differences towards the end of the composting. The concentrations of selected creosote components were reduced by between 96% and 100% after composting. There was no significant difference in reduction in concentration in both compost systems at p 0.05. Microbial activity correlated with reduction in creosote concentration.     

Persistence of Mycobacterium avium subsp. paratuberculosis and Other Zoonotic Pathogens during Simulated Composting, Manure Packing, and Liquid Storage of Dairy Manure

Livestock manures contain numerous microorganisms which can infect humans and/or animals, such as Escherichia coli O157:H7, Listeria monocytogenes, Salmonella spp., and Mycobacterium avium subsp. paratuberculosis (Mycobacterium paratuberculosis). The effects of commonly used manure treatments on the persistence of these pathogens have rarely been compared. The objective of this study was to compare the persistence of artificially inoculated M. paratuberculosis, as well as other naturally occurring pathogens, during the treatment of dairy manure under conditions that simulate three commonly used manure management methods: thermophilic composting at 55°C, manure packing at 25°C (or low-temperature composting), and liquid lagoon storage. Straw and sawdust amendments used for composting and packing were also compared. Manure was obtained from a large Ohio free-stall dairy herd and was inoculated with M. paratuberculosis at 10⁶ CFU/g in the final mixes. For compost and pack treatments, this manure was amended with sawdust or straw to provide an optimal moisture content (60%) for composting for 56 days. To simulate liquid storage, water was added to the manure (to simulate liquid flushing and storage) and the slurry was placed in triplicate covered 4-liter Erlenmeyer flasks, incubated under ambient conditions for 175 days. The treatments were sampled on days 0, 3, 7, 14, 28, and 56 for the detection of pathogens. The persistence of M. paratuberculosis was also assessed by a PCR hybridization assay. After 56 days of composting, from 45 to 60% of the carbon in the compost treatments was converted to CO₂, while no significant change in carbon content was observed in the liquid slurry. Escherichia coli, Salmonella, and Listeria were all detected in the manure and all of the treatments on day 0. After 3 days of composting at 55°C, none of these organisms were detectable. In liquid manure and pack treatments, some of these microorganisms were detectable up to 28 days. M. paratuberculosis was detected by standard culture only on day 0 in all the treatments, but was undetectable in any treatment at 3 and 7 days. On days 14, 28, and 56, M. paratuberculosis was detected in the liquid storage treatment but remained undetectable in the compost and pack treatments. However, M. paratuberculosis DNA was detectable through day 56 in all treatments and up to day 175 in liquid storage treatments. Taken together, the results indicate that high-temperature composting is more effective than pack storage or liquid storage of manure in reducing these pathogens in dairy manure. Therefore, thermophilic composting is recommended for treatment of manures destined for pathogen-sensitive environments such as those for vegetable production, residential gardening, or application to rapidly draining fields.     

Influence of free air space on microbial kinetics in passively aerated compost

The influence of free air space (FAS) on passively aerated composting has been reported, but the quantitative relationship between FAS and the microbial kinetics in passively aerated compost has not been investigated. This relationship was studied by composting dairy manure and straw in an enclosed, passively aerated, cylindrical vessel. Based on this experimental system, conceptual and numerical models were developed in which the compost bed was considered to consist of layered elements, each being physically and chemically homogeneous. The microbial activity in each layer was represented in order to predict oxygen and substrate consumption and the release of water and heat. Convective transport of air, moisture, and heat through the layers was represented. Microbial growth and substrate consumption rates were described using modified first-order kinetics for each of the mesophilic and thermophilic temperature regimes. The values of the microbial kinetic parameters were adjusted for each layer based on an innovative, non-linear, statistical analysis of temperature histories recorded at different layers in the compost bed during three treatments (i.e., FAS values of 0.45, 0.52, and 0.65). Microbial kinetic rate constants were found to follow a sigmoid relationship with FAS, with correlation coefficients (R(2)) of 0.97 for the mesophilic stage and 0.96 for the thermophilic stage. Temperature histories and airflow measurements from a fourth treatment (FAS value of 0.57) were used as an independent check of the model's performance. Simulation results indicate that the model could predict the general trend of temperature development. A plot of the residuals shows that the model is biased, however, possibly because many parameters in the model were not measured directly but instead were estimated from literature. The result from this study demonstrates a new method for describing the relationship between microbial kinetics (k(max)) and substrate FAS, which could be used to improve the design, optimization, and management of passively aerated composting facilities.     

The Impact of Using Mature Compost on Nitrous Oxide Emission and the Denitrifier Community in the Cattle Manure Composting Process

The diversity and dynamics of the denitrifying genes (nirS, nirK, and nosZ) encoding nitrite reductase and nitrous oxide (N₂O) reductase in the dairy cattle manure composting process were investigated. A mixture of dried grass with a cattle manure compost pile and a mature compost-added pile were used, and denaturing gradient gel electrophoresis was used for denitrifier community analysis. The diversity of nirK and nosZ genes significantly changed in the initial stage of composting. These variations might have been induced by the high temperature. The diversity of nirK was constant after the initial variation. On the other hand, the diversity of nosZ changed in the latter half of the process, a change which might have been induced by the accumulation of nitrate and nitrite. The nirS gene fragments could not be detected. The use of mature compost that contains nitrate and nitrite promoted the N₂O emission and significantly affected the variation of nosZ diversity in the initial stage of composting, but did not affect the variation of nirK diversity. Many Pseudomonas-like nirK and nosZ gene fragments were detected in the stage in which N₂O was actively emitted.     

Effects of age of cattle,turning technology and compost environment on disappearance of bone from mortality compost

As residual bones in mortality compost negatively impact subsequent tillage, two studies were performed. For the first study, windrows of mature cattle or calves were placed on a base of barley straw and covered with beef manure. Windrows were divided into two sections and turned at 3-month intervals. Approximately 5000 kg of finished compost per windrow was passed through a 6 mm trommel screen, with bones collected and weighed. Bone weight was 0.66% of mature cattle compost and 0.38% of calf compost on a dry matter basis, but did not differ after adjustment for weights of compost ingredients. In a subsequent study, four windrows were constructed containing mortalities, straw and beef manure (STATC) or straw, manure and slaughter waste (STATW). Also, straw, beef manure and slaughter waste was added to an 850 L rolling drum composter (DRUMW). Fresh bovine long-bones from calves were collected, weighed and embedded in the compost. Bones were retrieved and weighed when windrows were turned, or with DRUMW, after 8 weeks. Temperatures achieved followed the order STATW > STATC > DRUMW (p < 0.05). Rate of bone disappearance followed a pattern identical to temperature, with the weight of bones in STATW declining by 53.7% during 7 weeks of composting. For STATC, temperatures were uniform over three composting periods, but bone disappearance was improved (p < 0.05) when compost dry matter was lower (46%), as compared to 58%. Using a ratio of five parts manure to one part mortalities, results of this study demonstrated that residual bone was <1% of cured cattle compost and may be reduced by maintaining a high compost temperature and moisture content.     

Changes in Bacterial and Fungal Communities across Compost Recipes,Preparation Methods,and Composting Times

Compost production is a critical component of organic waste handling, and compost applications to soil are increasingly important to crop production. However, we know surprisingly little about the microbial communities involved in the composting process and the factors shaping compost microbial dynamics. Here, we used high-throughput sequencing approaches to assess the diversity and composition of both bacterial and fungal communities in compost produced at a commercial-scale. Bacterial and fungal communities responded to both compost recipe and composting method. Specifically, bacterial communities in manure and hay recipes contained greater relative abundances of Firmicutes than hardwood recipes with hay recipes containing relatively more Actinobacteria and Gemmatimonadetes. In contrast, hardwood recipes contained a large relative abundance of Acidobacteria and Chloroflexi. Fungal communities of compost from a mixture of dairy manure and silage-based bedding were distinguished by a greater relative abundance of Pezizomycetes and Microascales. Hay recipes uniquely contained abundant Epicoccum, Thermomyces, Eurotium, Arthrobotrys, and Myriococcum. Hardwood recipes contained relatively abundant Sordariomycetes. Holding recipe constant, there were significantly different bacterial and fungal communities when the composting process was managed by windrow, aerated static pile, or vermicompost. Temporal dynamics of the composting process followed known patterns of degradative succession in herbivore manure. The initial community was dominated by Phycomycetes, followed by Ascomycota and finally Basidiomycota. Zygomycota were associated more with manure-silage and hay than hardwood composts. Most commercial composters focus on the thermophilic phase as an economic means to insure sanitation of compost from pathogens. However, the community succeeding the thermophilic phase begs further investigation to determine how the microbial dynamics observed here can be best managed to generate compost with the desired properties.     

Variation in microbial population during composting of agro-industrial waste

Two compost piles were prepared, using two ventilation systems: forced ventilation and ventilation through mechanical turning. The material to compost was a mixture of orange waste, olive pomace, and grass clippings (2:1:1 v/v). During the composting period (375 days), samples were periodically taken from both piles, and the enumeration of fungi, actinomycetes, and heterotrophic bacteria was carried out. All studied microorganisms were incubated at 25 and 55 °C after inoculation in appropriate growth media. Fungi were dominant in the early stages of both composting processes; heterotrophic bacteria proliferated mainly during the thermophilic stage, and actinomycetes were more abundant in the final stage of the composting process. Our results showed that the physical and chemical parameters: temperature, pH, moisture, and aeration influenced the variation of the microbial population along the composting process. This study demonstrated that composting of these types of wastes, despite the prolonged mesophilic stage, provided an expected microbial variation.     

Compost biofiltration of ammonia gas from bin composting

The effects of the manure compost/coconut peels on the ammonia removal efficiency were examined from dairy manure composting mixed with crop residues. The high rapid composting and manure compost biofiltration experiments consisted of three biofilter vessels with one composter. Dairy manure amended with rice hulls and sawdust was composted in 605 L pilot-scale composter using continuous aeration for 19 days. Three pilot-scale manure compost biofilter amended with media bed 500 mm in depth and 300 mm in diameter were built to clean ammonia emission from composter, respectively. The manure compost biofilter media in the three experimental vessels was using a 50:50 by weight mixture of manure compost and coconut peels (MC/CP). The ammonia concentrations at the inlet and outlet biofilter media were measured by boric acid traps as described by Hong et al. [Hong, J.H., Keener, H.M., Elwell, D.L., 1998. Preliminary study of the effect of continuous and intermittent aeration on composting hog manure amended with sawdust. Compost Science and Utilization 6 (3), 74-88]. Results indicated that the mixture of MC/CP performed well as a biofilter media and the ammonia removal efficiency was 100% for the filter depth of 500 mm.     

葡萄籽对猪粪秸秆高温堆肥中微生物群落与碳氮含量的影响

以猪粪与秸秆(鲜质量10.5∶1)为基础,在自制的强制通风静态堆肥反应箱中进行堆肥化试验,研究添加8%葡萄籽对猪粪秸秆高温堆肥中微生物群落演替和碳氮转化的影响.在堆肥化的30 d里,分7次采集不同时期的堆肥样品,测定堆肥中微生物区系、微生物生理群的数量及堆肥碳氮含量.结果表明：添加葡萄籽使堆肥中细菌数量略高、放线菌数量显著增加、真菌数量明显降低,细菌/放线菌下降;氨化细菌和反硝化细菌数量降低;而硝化细菌、固氮菌和纤维素分解菌数量增多;铵态氮和有机碳含量下降,而硝态氮含量明显提高.堆肥中硝态氮含量与放线菌数量呈极显著正相关关系.添加葡萄籽使堆体升温快且高温期稳定,堆肥含水率波动较小,从而使堆肥高温期放线菌和亚硝化细菌的波动较小,数量较高,有利于堆肥中硝态氮含量的增加.     

Changes in the microbial community structure during thermophilic composting of manure as detected by the quinone profile method

Quinone profiles and physico-chemical properties were measured to characterize the microbial community structure during a 14-day thermophilic composting of cattle manure mixed with rice straw as a bulking agent. The change in total quinone content (TQ) and the divergence of quinone (DQ) indicated that the microbial biomass reached a peak followed by a decrease, whereas the microbial community diversity increased continuously during the composting process. The high mole fraction of ubiquinones in the raw materials, and at the beginning of the composting period suggested that fungi and/or Proteobacteria were present. The predominance of MK-7 from days 3 to 7 suggested that Bacillus spp. were the main microbial species. An increase in partially saturated and long-chain menaquinones during the latter composting period indicated that the proliferation of various species of Actinobacteria was occurring. The microbial community structure, as expressed by TQ and DQ, corresponded well to physico-chemical properties such as the C/N ratio, pH, O₂ consumption and compost mass reduction.     

Effect of matured compost as a bulking and inoculating agent on the microbial community and maturity of cattle manure compost

Cattle manure composts were consecutively manufactured. Compost that reached maturity first was used as a bulking and inoculating agent for subsequent compost production. The microbial community was measured through phospholipid fatty acid analysis. Changes in the content of fatty acid methyl esters derived from phospholipids were similar in all the composts. The diversity index for the fatty acid methyl ester content increased in the secondary-produced compost from the onset of composting. Microbial succession was accelerated using matured compost. The proportion of biomarker fatty acids for gram-positive bacteria also increased in the secondary-produced compost from the early stage of composting. Changes in germination index indicated the maturity stage of the compost. The proportion of biomarker fatty acids for gram-positive bacteria was positively correlated to the germination index, indicating that phospholipid fatty acid analysis is an indicator for evaluating the maturity of cattle manure composts.     

Patterns and quantities of NH(3), N(2)O and CH(4) emissions during swine manure composting without forced aeration--effect of compost pile scale

To evaluate the NH(3), N(2)O, and CH(4) emissions from composting of livestock waste without forced aeration in turned piles, and to investigate the possible relationship between the scale of the compost pile and gas emission rates, we conducted swine manure composting experiments in parallel on small- and large-scale compost piles. Continuous measurements of gas emissions during composting were carried out using a chamber system, and detailed gas emission patterns were obtained. The total amount of each gas emission was computed from the amount of ventilation and gas concentration. NH(3) emission was observed in the early period of composting when the material was at a high temperature. Sharp peaks in CH(4) emission occurred immediately after swine manure was piled up, although a high emissions level continued after the first turning only in the large-scale pile. N(2)O emissions started around the middle stage of the composting period when NH(3) emissions and the temperature of the compost material began to decline. The emission rates of each gas in the small and large piles were 112.8 and 127.4 g NH(3)-N/kg T-N, 37.2 and 46.5 g N(2)O-N/kg T-N, and 1.0 and 1.9 g CH(4)/kg OM, respectively. It was found that changing the piling scale of the compost material was a major factor in gas emission rates.     

Composting of spent mushroom compost, carnation wastes, chicken and cattle manures

This study has purposed to determine the optimum mixture ratio of used mushroom compost, chicken manure, cattle manure and carnation waste for composting. For this purpose, these materials have been mixed in seven various ratios (R1-R7) and composted in the experimental composting reactors. The highest dry material losses and temperature values have been obtained by the R4 which contains 50% carnation waste, 25% chicken manure and 25% spent mushroom compost. Beside R4, mixtures of R2, R5 and R6 have also provided high process temperature and dry material loss values. The lowest dry material loss and temperature values have been obtained in the R7 which contains only carnation wastes. In the study, it has also seen that FAS (free air space) parameter is effective on the process and must be in the interval of 24-32%.