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1.
? As more composting facilities come on line across the United States, and a wider spectrum and greater quantity of organic materials are composted, the need to develop a variety of markets for their end products, i.e., compost or mulch, will become ever more critical to the future growth potential for composting and its success. It is often stated that high quality compost will always find a market. However, the economic implications of producing a high quality compost need to be better understood. Publicly and privately operated composting facilities need to compare the costs for building or improving their composting programs to the associated economic returns, i.e., the increased selling price for their product (or, if the product is not sold, the increased avoided cost for what the compost/mulch product is substituted for) and other economic implications.

The scarcity of published information on the costs of producing marketable compost at U.S. municipal solid waste composting (MSW) facilities is largely due to the minimal experience in producing and marketing these composts in this country. In order to improve both facility operation and compost quality, most facilities that have operated for more than one year are making modifications, particularly in the type of feedstock, front-end process, composting process, and final compost processing. A summary of such changes is presented for nine U.S. plants, but little information is available on the costs of these modifications, nor their impact on compost quality. Information is also presented about the European experience with MSW composting, emphasizing the importance of producing better quality compost, and the need to fully account for the added costs associated with producing a higher quality compost.  相似文献   

2.
(Jpn. J. Soil Sci.Plant Nutr., 77, 283–291, 2006)

Nutrient amounts in livestock manure management, including manure treatment and use, were estimated using published statistical data and other information. The eight categories for manure treatment were defined in this study as composting at facility, composting at stockyard, raw feces, dried feces, urine, slurry, purification and other. The three categories for use of manure were defined as application to farmland, sale and exchange and other.

The regional daily excretion units per head of dairy and beef cattle, including the amount of excreta, nitrogen (N), phosphorus (P) and potassium (K), were calculated based on the quantities and qualities of feed in each region. There was found to be a difference in the values for Hokkaido and other regions.

Concerning manure treatment methods in the dairy sector, the sum of the proportion of raw feces and compost at stockyard was high in Hokkaido. On the other hand, the sum of the proportion of composting at facility and dried feces was high in Hokuriku, Tokai, Kinki and Shikoku. In Kyushu, the proportion of slurry production was higher than in any other region.

The amounts of N, P, and K in compost estimated in this study were compared with those calculated from published statistics. The results were as follows. The amounts of N, P, and K in dairy cattle compost, N and K in beef cattle compost, and N in poultry compost in this study were similar to the amounts cited in reported statistics. The amounts of P in beef cattle, swine, and poultry compost in this study were lower than those cited in reported statistics.

As for the use of manure, application to farmland is the most common use of manure in the dairy and beef cattle sector. The proportions of purification, and sale and exchange were high for the swine and poultry sectors, respectively.

Large amounts of liquid manure, such as urine and slurry, are applied to farmland. To clarify the nutrient load resulting from liquid manure, the usable amount of dairy slurry was calculated based on both the standard application rate of fertilizer and the area of grassland and forage crops. As a result, the amount of usable N was lower than the amount of liquid manure N in the Kanto-Tosan, Tokai and Kinki regions.  相似文献   

3.
A major barrier to adoption of composting by the livestock industry is a lack of information regarding the relative economic advantages and disadvantages for producing and marketing compost. The ten markets evaluated in this research are seen as typical markets for horticultural products or markets that have the greatest potential interest in compost. The focus of the research was to determine and evaluate potential paying markets for compost using Illinois as a model. Approximately 2,275 surveys were mailed to members of various horticultural trade associations in Illinois. Questions included inquiries as to the type of business conducted, the current use of compost and whether it was thought that the company had an organic waste problem. Questions were also asked regarding the respondents' beliefs about the economics of making and using compost, and perceived benefits from utilizing compost. A 33.7% response rate was achieved with 746 surveys returned and analyzed. Substantial numbers of respondents were involved in commercial nursery, golf course and lawn care operations. The operation classifications showing the most interest in composting were commercial tree growers, commercial nurseries and greenhouses, landscape contractors and lawn care operations. A majority of the respondents have either used compost in the past or are currently using compost. Of the respondents who reported using compost, a majority (P<0.05) were satisfied with the results. Most compost users reported purchasing compost in bulk as opposed to in bags. The primary reasons cited for using compost were related to soil tilth, building humus content of the soil and increased plant growth. Replacement of chemical fertilizer use and greater seed germination were not cited as primary reasons for using compost. In addition, respondents to the survey reported that development of quality standards for compost would not encourage use.  相似文献   

4.
针对规模化肉牛场粪污的收集与处理问题,以干清粪工艺为研究对象,总结归纳了规模化肉牛场粪污收集量的计算公式,并以1万头肉牛养殖场为例计算了粪污的产生和收集量,在此基础上选取了堆肥技术处理牛粪,进行了牛粪堆肥处理工艺设计。结果表明:干清粪工艺下规模化肉牛场粪污收集量可由公式直接算出,粪污收集率系数为0.83。养殖规模为1万头的肉牛养殖场,每天的粪尿收集量为150 t,含水率为82%。日处理210 t原料(牛粪150 t+辅料60 t,含水率60%),可产生含水率35%的堆肥产品93.04 t;堆肥项目主要土建工程占地面积为17 738 m2,采用连续动态好氧堆肥处理工艺和配套设备后,实现了整个系统的自动化运行。  相似文献   

5.
Composting could be used in the pulp and paper industry to treat primary sludges as an alternative to landfilling. The objective of this project was to compost and evaluate a pulp and paper sludge for use as a soil amendment/mulch. Primary sludge, tailings, wood ash (0, 5 or 10 percent by volume), and paunch (cattle stomach contents and tissue) from a slaughterhouse were composted in a 91 m windrow that was turned one to two times per week. The pile moisture content and temperature were controlled at 50 percent and 57–63°C during 14 weeks of composting. The compost was then cured for 4 weeks for a total treatment time of 18 weeks. Sludge dry mass decreased by approximately 50 percent, pH increased slightly to 8.2 to 8.5, and carbon-nitrogen ratio decreased from 270:1 to 14–67:1 after composting and curing. Electrical conductivity of all final composts was over 4 dS/m. Shoot biomass of tomato plants grown in a compost-amended medium (50 percent compost, 25 percent sand, 25 percent perlite by volume) improved with composting time but was still only 35–65 percent that of plants grown in a peat moss-amended medium (control). Shoot weight and height of poplar plants grown in soil amended with aged compost were unaffected by compost application rate (incorporated or as a mulch) at less than or equal to 180 Mg/ha. In summary, this study demonstrated that a pulp and paper sludge and wood ash mixture yielded a compost that could be used as a low quality mulch or soil amendment for poplar.  相似文献   

6.
国内外堆肥标准分析及其对中国的借鉴启示   总被引:11,自引:2,他引:9  
中国农业废弃物产量巨大,堆肥是农业废弃物资源化利用的主要方式之一,也是养分和有机质回收到土壤中的方法。结合国内外堆肥标准制定情况,通过分析对比无害化指标、有机质、总养分、重金属、含水率等指标,指出中国存在就农业废弃物处理缺乏专业化堆肥及有机肥标准推进委员会、对堆肥产品中氮磷钾和有机质含量的最低限值较高及未建立堆肥标准体系等问题。建议国家组建堆肥标准制定专家委员会或堆肥协会,进一步规范有机肥生产运行管理,进一步修订有机肥、生物有机肥、沼肥等标准,建立完善的堆肥标准体系。  相似文献   

7.
The occurrence of bovine spongiform encephalopathy (BSE) in Canada has resulted in the implementation of regulations to remove specified risk material (SRM) from the food chain. SRM includes the distal ileum of all cattle, and the skull, brain, trigeminal ganglia, eyes, palatine tonsils, and spinal cord and dorsal root ganglia of cattle ≥30 months of age. Composting may be a viable alternative to rendering for SRM disposal. In our study, two bulking agents, barley straw and wood shavings, were composted with beef manure along with SRM in passively aerated, laboratory-scale composters. Both composts heated rapidly, exceeding 55°C after 3 days with oxygen declining in the early composting stage with wood-shaving compost, but returning to near-original levels after 5 days. During composting the two matrices differed (P <0.05) only in water content, TC and bulk density. In the final compost, water content, TC and C/N ratio were higher (P < 0.05), while EC was lower (P < 0.05) in the wood shavings as compared to the straw compost. Approximately 50% of SRM was decomposed after 15 days of composting, with 30% of SRM being decomposed within the first 5 days. Phospholipid fatty acid (PLFA) profiles were used to characterize the microbial communities and showed that Gram positive bacteria were predominant in compost at day 5, a point that coincided with a rapid increase in temperature. Gram negative bacteria and anaerobes declined at day 5 but populations recovered by day 15. Fungi appeared to be suppressed as temperatures exceeded 55°C and did not appear to recover over the remainder of the composting period, with the exception of the straw compost at day 15. On day 5, Actinomycetes increased in the straw compost, but declined in the wood shavings compost, with this group increasing in both types of compost at day 15. Although temporal changes were evident, compost matrices or depth within the composter did not obviously influence microbial communities. Decomposition of SRM also did not differ between compost matrices or with depth in the composters. These results suggest that SRM decompose rapidly during composting and that both mesophilic and thermophilic microbial communities play a role in its decomposition.  相似文献   

8.
The use of leaf amendment in woodchips/sludge composting was studied in pilot-scale and full-scale operations. Use of leaves at a rate of 20 percent by volume was compatible with present practices and equipment at the Columbus Compost Facility, but higher rates caused materials handling and curing problems and would necessitate system modifications. Only very slight reduction in new woodchip usage was observed for the 20 percent leaf amendment, but output of sieved-finished compost was doubled. Leaf usage increased airflow requirement per unit dry matter during the initial stage of composting but decreased ammonia release throughout the composting process. On the other hand, use of recycled materials, compost and sieved woodchips, increased ammonia release. Adequate moisture and periodic turning in the pilot-scale studies enhanced composting for all treatments. Leaf usage may necessitate forced aeration during curing to keep full size piles aerobic. In addition, leaf usage increased the total materials handling requirement for operating the full-scale system by 16 percent, and it was concluded that careful consideration of materials handling is the major concern for a system's operating efficiency.  相似文献   

9.
为了优化堆肥工艺,提高堆肥产品质量,研究黑曲霉对牛粪堆肥腐熟度和纤维素降解的影响.该研究以牛粪为原料,小麦秸秆为辅料,以不添加黑曲霉为对照,分别添加1%、2%和3%的黑曲霉进行好氧堆肥,研究了黑曲霉不同添加量对腐熟度指标、养分含量、腐殖质组成以及纤维素组分的影响,并采用激发发射荧光光谱结合荧光区域积分(Excitati...  相似文献   

10.
The management of biodegradable wastes is increasing, including the use of waste as a source of energy. Anaerobic digestion involves organic-matter decomposition under anoxic conditions by a microbial consortium, obtaining a source of renewable energy (biogas), mainly constituted of a mixture of carbon dioxide (CO2, 25–45 percent), methane (CH4, 55–75 percent), and the digested substrate (digestate). The direct application of digestate into agricultural soils presents several problems. These include agronomic (low concentration of nutrients, high salinity, etc.), economic (cost of transport and handling), and environmental issues (gaseous emissions, nutrient leaching, and pathogen spread). However, it is possible to obtain quality compost from the solid fraction of digestate, and the compost obtained can have good properties for use as container growing medium or for crop production. In this work, an optimized procedure has been developed for composting the solid phase of a digestate obtained from a continuous, anaerobic codigestion of cattle slurry with 84 percent of cattle manure, 7.4 percent of a mixture of maize/silage, and 8.6 percent of peach-juice pulp (fresh-mass basis). The experiment was designed to optimize pH, carbon (C) / nitrogen (N) ratio, and moisture values in order to maximize self-heating activity, using Dewar self-heating tests. A factorial optimization of moisture and C/N ratio was carried out. In the best moisture-C/N ratio treatment, pH optimization was also developed. To predict the optimum conditions of the studied residue related to the increase of temperature per dry matter, a multiple correlation analysis based on moisture, C/N ratio, and pH was developed, which explained 80 percent of the variance in this experiment.  相似文献   

11.
Cornell University Farm Services collects recyclable organics from various locations around the University including the dining halls and other food service establishments, the veterinary hospital, satellite dairy cattle, horse and chicken farms, cropping operations, and greenhouses. In 2013, they diverted approximately 6714 metric tons of organic residuals to the compost facility. A questionnaire was developed to get information from the facility in order to calculate greenhouse gas emissions for each step in this process including savings from carbon sequestration through compost use. It was found that in 2013, Cornell's compost facility emitted 104.6 metric tons carbon equivalent (MTCE) and saved 201.4 MTCE through compost use for a total carbon footprint savings of 96.7 MTCE/year (carbon negative). This equates to 0.0154 MTCE/tonne feedstock emitted and 0.03 MTCE saved through compost use for a total carbon footprint savings of 0.0146 MTCE/tonne fresh matter. These values are specific to this facility, but the questionnaire and calculations can be used by compost facilities to calculate the carbon footprint of composting.  相似文献   

12.
In utilizing municipal solid waste (MSW) as fuel for energy production, about 10 percent remains as a noncombustible small size fraction byproduct called refuse derived fuel unders (RDFU). We assessed the feasibility of using RDFU to produce compost for land applications, in the context of acceptable limits for metals. Periodic random samples from two batches of RDFU obtained during composting were analyzed for the heavy metals Cd, Cu, Pb, and Zn, and for the plant nutrients N, P, and K. The heavy metal content (mg/kg, dry weight) in all samples ranged from 1.7-12.7 (Cd), 201-3217 (Cu), 267-5002 (Pb), 344-2079 (Zn). The total variability of these elements within a batch of RDFU compost was high, with relative standard deviations (RSD) ranging from 20-107 percent. Estimates of the number of samples needed to obtain a 10 percent uncertainty in the averages ranged from 5-138, depending on the analyte and the compost batch. Leachability tests showed little leaching of metals in the RDFU compost. The high variability in heavy metal content and the excessive Pb concentrations in this RDFU may limit its use for composting.  相似文献   

13.
Washington State University produces a manure-based compost of high pH (>8) and low N content (1 percent) by windrow composting campus wastes. Annual production at the four-acre facility is 18-20,000 cubic yards. In the interest of producing compost of higher N content and lower pH, ten experimental piles were constructed to investigate the effects of different feedstocks on the composting process, end quality and agronomic performance. Biosolids and manure were compared at two rates of bedding both with and without coal ash. Compost temperature and inorganic N content during 96 days of active composting are reported along with end product nutrient analysis and metal concentration. The composts behaved differently based on the N feedstock and level of bedding in the mix. Compost quality was influenced by the characteristics of the feedstocks. Applying the composts to an eroded hilltop (50 Mg/ha) increased winter wheat yield, but there were no differences among the ten composts.  相似文献   

14.
Wood ash from a wood-fired, electrical generating plant was examined as a potential amendment in municipal biosolids and yard waste composting applications. The rate of composting and the final compost quality (chemical, physical, and plant growth characteristics) were examined. Yard waste (leaves, grass, and wood chips) and a municipal biosolids-chip mixture were either not amended or amended with wood ash at eight percent or five percent by weight, respectively, and then composted outdoors in insulated, 1700L, aerated reactors. Yard waste piles heated rapidly to 60°C within six to seven days, whereas biosolid piles heated more slowly to a maximum of 52 to 57°C within nine to 11 days. Ash had little, if any, effect on the time-temperature response. In general, ash-amended compost had higher pi I, plant nutrient, and salt contents. Tomato plants (Lycopersicum esculentum) produced 100 percent more shoot biomass in biosolids than in yard waste compost media. Poor plant growth in the yard waste compost was likely due to the high initial pH and salt content of the growth medium. In yard waste media, tomato plants germinated and produced more shoot biomass in the control compost than in the ash-amended compost.

A pH neutralization study indicated that wood fly ash could be used as an economical substitute for lime which is commonly used to stabilize municipal biosolids prior to land filling or land application. Wood fly ash (pH = 13.2-13.4), when added to biosolids at a 2 to 1 ratio by weight, raised the pH of the mixture to 12.0.  相似文献   

15.
Alternate technologies of compost manufactured from poultry litter (manure) were studied as a means of producing a value-added product for the landscape and nursery industry. Static pile and turned windrow technologies were investigated on a commercial scale with the composting of nearly 300 tons of material. The major difference between the technologies is the amount of energy and labor required. Static pile systems require less energy but more time than windrow turned systems. There was no process advantage found for passively aerated static piles over static piles but costs of passive aeration for pipes and labor were higher than for static piles. Machine turned windrows completed active temperature production within 100 days while portions of both the static and passively aerated piles continued to actively compost past 300 days. Process operational costs and compost quality were similar among the compost methods studied. Production operational cost is driven by the cost of compost ingredients and accounted for 60 to 70% of the cost in the pilot study. Ingredients were poultry litter, wood chips and sawdust. Screened compost was produced at an operational cost of $30 while unscreened compost could be produced for $20 per ton of compost. A production scheme where poultry litter is static pile composted on farms for later transport to regional processing centers appears feasible. This two-part composting procedure will eliminate the transport of raw litter and improve poultry biosecurity. Most likely, a private compost business would provide the expertise, on-farm compost procedures and operate the regional facility.  相似文献   

16.
Management of organic wastes is essential to reduce environmental pollution and increase resources of plane nutrients for crop production. This study was undertaken to evaluate major organic wastes produced in northwestern Pakistan for characteristics that are useful for composting. Organic wastes such as manures, municipal wastes (MW), crop residues, fruit/vegetable wastes, and yard wastes contained large reserves of nutrients. Manures had high nitrogen (N) and crop residues had low N. Crop residues were relatively dry (7–12% moisture); MW, poultry manure, sheep manure, leaves, and city garbage were moderately moist (27–47% moisture), whereas cattle manure (CM), fruit and vegetable wastes, and grass clippings were wet (62–89% moisture). The compost developed from mixing MW with CM matured early and had low C/N ratio compared with either source alone. These results suggested that MW could be converted into compost when mixed with CM. The inoculation of wastes with effective microbes (EM) was ineffective in expediting the process of composting.  相似文献   

17.
Oil palm empty fruit bunches (EFB) composting is increasingly being considered by tropical farmers as a worthwhile alternative to direct spreading in the field. EFB are ligno-cellulose residues comprising 46% cellulose and 16.5% lignin with a high C:N ratio ranging from 45 to 70. In hot regions, it is essential to control variations in the water content of the substrate. This case study set out to optimize the EFB composting procedure by monitoring two key factors, namely the nutritional balance of the biomass and its water content. The trial was conducted on a composting platform belonging to the PT SMART Tbk company (Indonesia) in windrows comprising shredded EFB watered weekly with oil mill effluents. The quantity of effluent to be added was calculated so as to systematically top up to 60% humidity. The initial C:N ratio of the EFB was reduced by urea and/or ripe compost applications (seeding). Application times and rates were studied on two windrows, one in an open area, the other in an area sheltered by a roof to prevent over-rapid drying. After ten weeks the compost could be considered ripe for all the treatments; at that stage, composting had reduced the volume and initial weight of the fresh EFB by 85% and 50% respectively. The combined action of a temperature rise and windrow turning led to substantial water losses through evaporation, resulting in a sudden drop in windrow humidity at the start of composting. When rainfall was insufficient, effluent applications became essential. The total amount of effluent to be applied during composting (without rainfall) was around 3 m3 per initial tonne of EFB. This amount approximately corresponded to the standard effluents : EFB ratio in the oil mill. Inoculation of the mass of EFB to be composted with ripe compost had a significant effect on the speed with which the mixture was reduced. A urea application a fortnight after the start of fermentation seemed to be beneficial. The resulting compost had a good agronomic value. However, the mineral balance was considerably affected, as the nutrients provided by the effluents were poorly retained by the substrate, and partially lost in percolation water following the weekly watering operations. For instance, almost 50% of the phosphorus, 70% of the potassium, 45% of the magnesium and between 10% and 20% of the calcium theoretically applied were lost ten weeks into the trial. Better distribution of the effluent applications, combined with a system to recover the leachings, should substantially reduce these losses, while maintaining suitable humidity for microbial degradation.  相似文献   

18.
ABSTRACT

Most composters in the United States use open-windrows. During high intensity precipitation events, uncontained water running off of the surface of the compost piles can potentially contaminate surface waters with nutrients and metals. Water that is absorbed poses no runoff concern but may threaten groundwater quality. To gain insight into these processes, stormwater runoff fractions and water holding capacity of compost piles have been characterized for greenwaste (GW) and biosolids (BS) materials. Laboratory scale experiments were conducted using days 1, 7, and 14 materials representing three different stages of composting. This study also evaluated sloped and flat-top as different pile geometries and surfactant use for promoting infiltration. Results indicate that fresh materials were most hydrophobic and the infiltration rates increased with increased composting times. The water storage capacity of the compost pile increased with the age of the compost pile. Compost water storage capacities could not be reliably estimated as the difference between field capacity and as-received water contents.  相似文献   

19.
Despite the commercialization of a variety of different composting systems, the design and operation of composting systems to minimize the cost of producing compost remains a major goal. Evaluation of how system design and management affects the time required to stabilize compost is critical to optimizing the process. In this study, analytical equations relating biological and physical factors and compost temperature, moisture, oxygen level and decomposition rates for aerobic composting are developed. The study focused on the effects of intermittent aeration on the composting operation. A multi-parameter kinetic model in conjunction with heat and mass balance equations were used to predict and optimize the performance of composting systems. Equations evaluating airflow and on/off fan cycle times on composting temperature, oxygen and moisture were developed. Kinetic data from pilot scale experiments using three different feedstocks: municipal solid waste, biosolids/woodchips, and grass/leaves/brush were used in the derived equations to evaluate the composting systems operation.  相似文献   

20.
In comparison to traditional windrow composting, in-vessel composting techniques often represent more effective waste management options due to the reduced production of bioaerosols and leachate and the potential for better process control. Chemical processes occurring during the cocomposting of three common wastes (green waste, biosolids and paper processing waste) were studied using the forced aeration, static pile, in-vessel EcoPOD® composting system. Since no turning of the compost occurs within the static piles, spatial differences in the vessel were also monitored. These measurements revealed significant spatial gradients in temperature; however, this did not result in spatial differences in nutrients within the composting vessel. Significant differences in soluble N production were observed during the composting process following the series: green plus paper waste < green waste < green waste plus biosolids. After the active compost phase was over, and the compost was removed from the vessel and matured outside, we demonstrated that covering the compost was essential to preserve compost quality. Our study clearly shows that cocomposting of common waste feedstocks can be used to successfully manipulate the chemistry of the final compost making it suitable for multiple end uses. In addition, our study demonstrated that careful management of the compost maturing phase is also required to maximise quality and minimize pollution.  相似文献   

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