新型调理剂CTB-2污泥堆肥的氧气时空变化特征研究

采用新型CTB-2调理剂与城市污泥进行堆肥,研究了堆肥过程中氧气、温度的时空变化特征。结果表明,m（CTB-2调理剂）：m（污泥）=1：2能够有效降低污泥容重,改善堆体结构;堆体能够快速升温至高温期并持续7d以上,最终完成无害化;采用该比例的调理剂能够保证堆体的通风供氧,使堆体各层通风后的氧气体积分数都恢复至19％以上,最低氧气体积分数维持在数17％以上;堆肥过程中堆体的氧气体积分数、耗氧速率和温度都具有明显的层次效应,堆体耗氧速率呈先升高后降低的趋势,堆体通风后的氧气和最低氧气体积分数均随着堆肥的进行而增加。     

添加生物炭对猪粪好氧堆肥过程氮素转化与氨挥发的影响

为了减少好氧堆肥过程中氮素的损失,研究添加生物炭对猪粪好氧堆肥过程中氮素转化和损失的影响。设置不加生物炭对照(S1)以及猪粪秸秆中添加5%(S2)、10%(S3)、15%(S4)生物炭4个处理,监测堆肥过程中堆肥温度、氮素形态及氨挥发速率等的变化。结果表明,与对照相比,添加生物炭能够提高堆肥温度,提前2—3d进入高温期,缩短堆肥周期,提高堆肥品质。生物炭显著增加猪粪堆肥NO_3~--N的含量,降低了NH_4~+-N的含量,有利于NH_4~+-N向NO_3~--N转化;堆肥结束时,处理S2、S3和S4的NO_3~--N含量分别比对照提高了39.64%、46.68%和28.84%;添加生物炭明显降低了堆肥在高温期的氨挥发速率,且氨挥发累积排放量分别比对照降低了18.77%、25.35%和26.39%。与堆肥前相比,S1—S4总氮的增加率分别为9.7%、27.5%、28.6%和26.2%,添加10%生物炭的处理固氮效果最好。以上结果说明,猪粪堆肥过程添加生物炭更易促进堆肥腐熟、抑制氨气挥发和减少氮素损失,通过合理物料配比的好氧堆肥可以更有效地实现农业秸秆及猪粪的优质资源化利用。     

粪渣污泥好氧堆肥过程中主要理化性质的动态变化

进行了粪渣污泥的强制通风静态垛堆肥试验,分析了温度、氧气、含水率和挥发性有机物在堆肥不同阶段的变化特征。粪渣与木屑质量1∶1.5的比例下,能够实现快速高温好氧堆肥,堆体温度在高温期持续9d,达到无害化的卫生学要求。堆体耗氧速率在升温阶段后期上升到最大值,此后持续降低,到堆肥后期趋于稳定。据此提出了相应的通风策略。在堆肥过程中,物料的含水率和挥发性有机物含量持续降低,但到堆肥后期趋于稳定,堆肥结束时分别减小17个百分点和10.4个百分点。     

菌剂对堆肥的作用及其应用

好氧高温堆肥是一种受微生物控制的有机物降解和转化的过程。在堆肥过程的不同阶段对有机物降解起关键作用的微生物种群不同。接种菌剂可以使堆肥物料快速达到高温、控制堆肥过程中臭气的产生，缩短堆肥腐熟进程；可以有效杀灭病原体和降解有机污染物，提高堆肥质量。堆肥产品含有生物活性的微生物，作物增产效果显著。文章总结了接种菌剂在堆肥过程中的作用和应用效果，提出接种菌剂的研究首先应利用传统微生物研究法和先进的分子生态学技术摸清堆肥过程中微生物活动规律，逐步筛选出所需功能性菌群，在堆肥应用时要确定菌剂的最佳接种时间和接种量。     

堆肥调理剂研究进展

调理剂是堆肥过程中的重要辅料。通过添加调理剂，可以改善堆肥物料的理化条件，达到好氧微生物对生长环境的要求。文章综述了堆肥调理剂的分类，讨论了它在堆肥工程中的作用，并对研究方向进行了探讨。大量研究表明，调理剂在堆肥过程中起到调节物料w（C）／w（N）比、含水率、堆体自由空域、减少堆体臭气、改善堆肥养分和调控重金属等作用。目前，调理剂的研究重点在于其在堆肥过程的作用，而对复合型调理剂的开发、调理剂的作用机理及其在工程中的应用等问题关注较少。     

奶牛粪便翻堆式与槽式堆肥过程气体排放规律及养分损失原位监测

为探究奶牛粪便翻堆式与槽式堆肥过程中温室气体和氨气(NH₃)排放规律及养分损失情况,采用原位监测的方法,通过静态采气箱和气体在线监测设备,分别对奶牛粪便翻堆式和槽式堆体开展为期36 d的气体监测。结果表明,翻堆式堆肥过程中甲烷(CH₄)、氧化亚氮(N2_O)和NH₃排放主要集中于翻堆阶段;槽式堆肥过程中CH₄和NH₃排放主要集中于堆肥前期,N2_O排放则主要集中于堆肥中后期。堆体管理措施及物料特性显著影响堆肥气体的排放。翻堆式堆肥过程中翻堆对气体排放的影响大于堆肥理化因子如温度、含水率以及pH值;而槽式堆肥过程中,降低堆体的平均温度可同时减缓堆肥过程中CH₄、二氧化碳(CO₂)和NH₃的释放。从养分损失来看,翻堆式和槽式堆肥过程中碳素总损失量分别占堆肥物料初始总碳含量(TC)的27.16%和21.53%,其中约80%以上的碳素损失来自CO₂-C。而堆肥过程中氮素总损失量分别占堆肥物料初始总氮含量(TN)的18.67%和13.44%,其中约80%以上的氮素损失来源于NH₃N。该研究表明,在保证堆体物料腐熟的前提下,降低翻堆频率可显著减缓翻堆式堆肥过程中温室气体和NH₃的排放;降低槽式堆肥堆体的温度可显著减少堆肥过程中CH₄、CO₂和NH₃的排放。该研究结果对于减少堆肥过程气态污染物排放和养分损失,提高堆肥效率具有重要的指导意义。     

城市垃圾好氧堆肥处理的几个关键问题

介绍了城市垃圾好氧堆肥过程的几个关键问题，分析了堆肥过程中的微生物特性，提出以耗氧速率、C／N作为堆肥腐熟度综合判定指标。并简单介绍了国外应用较多的温度、氧浓度自动控制系统。     

不同类型外加碳源对制药污泥堆肥过程中青霉素降解的影响

以制药污泥为研究对象,采用葡萄糖、蔗糖、玉米秸秆粉及其混合物作为外加碳源,研究不同类型的外加碳源对堆肥系统一次发酵周期内温度、有机质等理化参数变化及青霉素的降解情况的影响.结果表明,堆体中有机质含量与外加碳源的量呈正比,堆体中有机质的质量分数随堆肥时间不断下降且趋于稳定.温度是青霉素降解的主要影响因素.外加碳源增加了堆体溶解性有机质质量分数,生物可利用碳源的增加促进了堆肥过程中微生物的转化作用,并有助于提高堆肥过程温度.在堆肥周期内外加碳源可以提高青霉素的降解速率(15 d内对照组青霉素降解率为94.44%,其他组均大于95%),且外加蔗糖与玉米秸秆粉的混合碳源处理组青霉素降解速率最快(15 d内降解率可达到99.08%).堆肥过程中升温阶段(中温阶段和高温阶段)青霉素含量与温度呈负相关(P0.01),与溶解性有机碳呈正相关(P0.01).15 d内所有处理组青霉素降解率均可以达到90%以上.     

微生物菌剂堆肥中草药渣中试研究北大核心CSCD

木质纤维素降解是中草药渣堆肥的主要难点.在前期小试的基础上,接种纤维素降解菌剂,将1 t新鲜药渣直接进行好氧堆肥.腐熟度指标T值和种子发芽指数(GI)显示,堆肥19 d左右就已经腐熟.堆肥过程中接种组(JZ)和对照组(CK)的纤维素平均降解速率分别为0.73 kg/d和0.64 kg/d,JZ比CK纤维素降解总量提高了13.39%,木质素降解量提高118.18%.第30天时,堆肥的含水率、p H、总养分、重金属等指标都达到有机肥料标准(NY 525-2012).接种菌剂提高了堆肥温度,加速了水分散失,促进了纤维素和木质的转化,有利于堆肥腐熟和提高肥料品质.因此,在中试规模上堆肥中草药渣生产有机肥是可行的.     

猎粪和锯末联合堆肥的中试研究

以3种配比的猪粪和锯末为原料，进行了联合堆肥中试研究。一次发酵采用温度反馈通气量控制的静态好氧堆肥系统，周期15d；二次发酵采用定期翻堆自然腐熟，周期30d。试验分析了堆制过程中温度、含水率、有机质、Ph值的变化。对堆肥产物的腐熟度和养分分析表明，3种配比的堆肥产物均可达到腐熟度要求。猪粪养分含量越高，产物养分越高。通过堆肥工艺的优化控制和加水措施，猪粪的锯末联合堆制可以在45d内获得高质量的有机肥，具有良好的应用前景。     

Environmental effects and risk control of antibiotic resistance genes in the organic solid waste aerobic composting system: A review

• ARGs were detected in livestock manure, sludge, food waste and fermentation dregs. • The succession of microbial community is an important factor affecting ARGs. • Horizontal transfer mechanism of ARGs during composting should be further studied. Antibiotic resistance genes (ARGs) have been diffusely detected in several kinds of organic solid waste, such as livestock manure, sludge, antibiotic fermentation residues, and food waste, thus attracting great attention. Aerobic composting, which is an effective, harmless treatment method for organic solid waste to promote recycling, has been identified to also aid in ARG reduction. However, the effect of composting in removing ARGs from organic solid waste has recently become controversial. Thus, this article summarizes and reviews the research on ARGs in relation to composting in the past 5 years. ARGs in organic solid waste could spread in different environmental media, including soil and the atmosphere, which could widen environmental risks. However, the conventional composting technology had limited effect on ARGs removal from organic solid waste. Improved composting processes, such as hyperthermophilic temperature composting, could effectively remove ARGs, and the HGT of ARGs and the microbial communities are identified as vital influencing factors. Currently, during the composting process, ARGs were mainly affected by three response pathways, (I) “Microenvironment-ARGs”; (II) “Microenvironment-microorganisms-ARGs”; (III) “Microorganisms-horizontal gene transfer-ARGs”, respectively. Response pathway II had been studied the most which was believed that microbial community was an important factor affecting ARGs. In response pathway III, mainly believed that MGEs played an important role and paid less attention to eARGs. Further research on the role and impact of eARGs in ARGs may be considered in the future. It aims to provide support for further research on environmental risk control of ARGs in organic solid waste.     

城市固体废弃物堆肥化处理的影响因素

城市固体废弃物的堆肥化处理已经成为各国越来越重视的方法。堆肥化处理是通过控制堆腐过程条件,使废弃物在短时间内最有效地达到稳定,杀灭病原菌,使产品可以安全地使用。本文对堆肥的原理及基本机理进行了介绍,同时对堆肥过程的重要参数（ 水分含量、有机质含量、 Ｃ／ Ｎ 比、ｐ Ｈ 值、通气量等） 进行了综述。     

Characterization and variation of dissolved organic matter in composting: a critical review

● Effect of composting approaches on dissolved organic matter (DOM). ● Effect of composting conditions on the properties of DOM. ● Character indexes of DOM varied in composting. ● The size, hydrophobicity, humification, and electron transfer capacity increased. ● The hydrophilicity, protein-like materials, and aliphatic components reduced. As the most motive organic fraction in composting, dissolved organic matter (DOM) can contribute to the transfer and dispersal of pollutants and facilitate the global carbon cycle in aquatic ecosystems. However, it is still unclear how composting approaches and conditions influence the properties of compost-derived DOM. Further details on the shift of DOM character indexes are required. In this study, the change in properties of compost-derived DOM at different composting approaches and the effect of composting conditions on the DOM characteristics are summarized. Thereafter, the change in DOM character indexes’ in composting was comprehensively reviewed. Along with composting, the elements and spectral properties (chromophoric DOM (CDOM) and fluorescent DOM (FDOM)) were altered, size and hydrophobicity increased, and aromatic-C and electron transfer capacity were promoted. Finally, some prospects to improve this study were put forward. This paper should facilitate the people who have an interest in tracing the fate of DOM in composting.     

Characteristics of night soil and leaf co-composting using aerobic static method

The main purpose of this work is to investigate the characteristics of night soil and leaf co-composting using aerobic static composting method. Three influencing factors, including proportion of night soil and leaf, aeration rate and aeration pattern, were investigated through the evolution of the principal physicochemical properties, i.e., temperature, oxygen consumption rate, organic matters, moisture content, carbon, nitrogen, carbon-to-nitrogen ratio and Germination index (GI). It was found that the 3∶1 (w∶w) mixture of night soil and leaf was capable of achieving the highest composting temperature, longest retention time of high temperature (55°C), and fastest organic matter degradation. The 0.14 m³·min^-1·m^-3 aeration rate was most beneficial to composting, and the mixture of night soil and leaf maintained the highest temperature for the longest duration and achieved the highest CO₂ content and GI. The continuous aeration pattern during composting was superior to an intermittent aeration pattern, since the latter delayed the composting process.     

The size distribution of airborne bacteria and human pathogenic bacteria in a commercial composting plant

•Bacterial concentrations from eight stages were 10⁴–10⁵copies/m³. •Diameter influenced clustering of bacterial and HPB lineages. •Dg of 8 HPB ranged from 2.42 to 5.09 μm in composting areas. •Dg of 8 HPB ranged from 3.70 to 8.96 μm in packaging areas. •HPB had high concentrations and small sizes in composting areas. Composting plants are regarded as one of the important sources of environmental bioaerosols. However, limitations in the size distribution of airborne bacteria have prevented our comprehensive understanding of their risk to human health and their dispersal behavior. In this study, different sizes of airborne bacteria were collected using an eight-stage impactor from a full-scale composting facility. Size-related abundance and communities of airborne bacteria as well as human pathogenic bacteria (HPB) were investigated using 16S rRNA gene sequencing coupled with droplet digital PCR. Our results indicate that the bacterial concentrations from the eight stages were approximately 10⁴–10⁵copies/m³. Although no statistical correlation was detected between the particle size and the Shannon index, the influence of size on bacterial lineages was observed in both composting and packaging areas. For airborne bacteria from different stages, the dominant phyla were Firmicutes, Proteobacteria, and Actinobacteria, and the dominant genera was Bacillus. Seven out of eight HPB with a small geometric mean aerodynamic diameter had a high concentration in composting areas. Based on diameters of 2.42 to 5.09 μm, most HPB in the composting areas were expected to be deposited on the bronchus and secondary bronchus. However, in the packaging areas, the deposition of HPB (diameters 3.70 to 8.96 μm) occurred in the upper part of the respiratory tract. Our results on the size distribution, abundance, and diversity of these bacteria offer important information for the systematic evaluation of bacterial pathogenicity and the potential health impacts on workers in composting plants and the surrounding residents.     

Characterising populations living close to intensive farming and composting facilities in England

• Bioaerosol emitted from farming and composting facilities may pose health risks. • We describe population characteristics around these sites and infer public concern. • Sites were mapped and overlaid with population, demographic and school data. • Approximately 16% of the population and 15% of schools are located near these sites. • More community health studies need to be conducted around these sites. Bioaerosol exposure has been linked to adverse respiratory conditions. Intensive farming and composting facilities are important anthropogenic sources of bioaerosols. We aimed to characterise populations living close to intensive farming and composting facilities. We also infer whether the public are becoming more concerned about anthropogenic bioaerosol emissions, using reports of air pollution related incidents attributed to facilities. We mapped the location of 1,257 intensive farming and 310 composting facilities in England in relation to the resident population and its characteristics (sex and age), area characteristics (deprivation proxy and rural/urban classification) and school locations stratified by pre-defined distance bands from these bioaerosol sources. We also calculated the average number of air pollution related incidents per year per facility. We found that more than 16% of the population and 15% of schools are located within 4,828 m of an intensive farming facility or 4,000 m of a composting facility; few people (0.01%) live very close to these sites and tend to be older people. Close to composting facilities, populations are more likely to be urban and more deprived. The number of incidents were attributed to a small proportion of facilities; population characteristics around these facilities were similar. Results indicate that populations living near composting facilities (particularly>250 to≤4,000 m) are mostly located in urban areas (80%–88% of the population), which supports the need for more community health studies to be conducted. Results could also be used to inform risk management strategies at facilities with higher numbers of incidents.     

Turnover and loss of nitrogenous compounds during composting of food wastes

Few people have so far explored into the research of the dynamics of various nitrogenous compounds (including water-soluble nitrogen) in composting of food wastes. This study aimed to investigate the solid-phase nitrogen, water-soluble nitrogen, nitrogen loss together with ammonia volatilization in the process of food wastes composting. A laboratory scale static aerobic reactor in the experiment was employed in the composting process of a synthetic food waste, in which sawdust was used as the litter amendment. In the experiment, oxygen was supplied by continuous forced ventilation for 15 days. The results have shown that the concentrations of total nitrogen and organic nitrogen decrease significantly in the composting process, whereas NH₄ ⁺-N concentration increases together with little fluctuation in NO₃ ^?-N. After composting, the total content of the water-soluble nitrogen compounds in the compost greatly increased, the total nitrogen loss amounted to 50% of the initial nitrogen, mainly attributed to ammonia volatilization. 56.7% of the total ammonia volatilization occurred in the middle and late composting of the thermophilic stage. This suggested that the control at the middle and late composting of thermophilic stage is the key to nitrogen loss in the food waste compost.