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1.
针对蓝藻资源化问题,概述国内外利用蓝藻制备有机肥、提取高纯度藻蓝蛋白、制备活性炭和藻粉这4种利用方式的特点、现状及应用进展。提出,应从高温好氧堆肥技术、藻蓝蛋白提取技术和藻水分离技术这3个方面,解决其关键技术问题并进行进一步研究开发。  相似文献   
2.
阐述了堆肥技术背景与基本原理。通过对国内示范项目运行情况的研究分析,提出了堆肥处理处置中应注意的工艺选择、处理规模、通风除臭、自动化与可靠性、减量化与稳定化,以及重金属、POPs、经营风险等问题。分析了堆肥处理处置全过程的经济成本,得出了该技术的参考运行成本;给出了该技术的适用条件和发展趋势。  相似文献   
3.
运用Gambit软件建立了污泥好氧发酵堆体的多孔介质模型,通过自行设计的实验装置获得了堆体的通风粘性阻力系数和惯性阻力系数以及功能膜压差与透气量之间的关系,用Fluent软件分析了堆体不同截面形状及底部通风管数量对堆体通风均匀性的影响,为确定合理的通风管数量及截面几何形状提供理论依据。对上海奉贤区城镇污水厂污泥处理工程发酵仓进行堆体流场模拟,确定堆体采用小拱形截面形状,堆高2 m,宽8 m,底部设置4条通风管,实际运行效果良好。  相似文献   
4.
利用新型梨形筒式好氧堆肥反应器,在通风量为3.0 L/min,搅拌频率为5 min/h的条件下,就不接种微生物、接种土著菌种、枯草芽孢杆菌与酵母菌时人粪便连续投加好氧堆肥效果进行了对比。堆制20 d即2个运行周期中各堆体的温度、含水率、COD、总氮、pH值与GI等的变化表明,接种微生物可以显著提高堆体的升温速率与堆体平均温度、COD降解率、GI(P<0.01),堆肥可迅速达到完全腐熟。接种土著菌种效果最为明显(P<0.01),其后相继为枯草芽孢杆菌与酵母菌。接种土著菌种可使堆体温度在50℃以上维持18 d,第8天COD降解率达到61.17%、总氮损失率为25.75%,第6天时GI达到108.22%。  相似文献   
5.
With the increase of urbanization, municipal solid waste has also increased. Therefore, the need for solid waste management is also increasing compared with earlier decades. Composting is a good option for the recycling of solid waste; however, it produces leachate, which requires proper treatment systems to prevent environmental degradation. Due to high chemical oxygen demand (COD) concentrations in compost leachate, anaerobic treatment is the best option for handling the effluent, and an anaerobic baffled reactor (ABR) is one such anaerobic reactor that can be used for its treatment. Because of high ammonia and heavy metal concentrations, as well as the possibility of sludge washout in ABRs, it is important to use proper media, such as zeolite, which can reduce inhibition effects and sludge washout from the reactor. Anaerobic treatment, especially during the methanogenesis phase, is sensitive, and pH and alkalinity are parameters that influence the treatment. Therefore, adjusting these parameters within a normal range is very important to the proper functioning of anaerobic systems. In this study, a pilot‐scale ABR was used, and the last 4 of the 8 ABR compartments were filled with zeolite. The bioreactor was operated at hydraulic retention times (HRT) of 3, 4, and 5 days, with zeolite filling ratios of 10%, 20%, and 30%, and influent COD concentrations of 10,000, 20,000, and 30,000 milligrams per liter (mg/L). In this study, pH value was 6.43 ± 0.1, 6.96 ± 0.3, and 6.96 ± 0.25 at filling ratios of 10%, 20%, and 30%, respectively. According to the results, in all filling ratios, no significant changes were observed in the pH value when the organic loading rate increased and its amount was within a constant range. Influent alkalinity was equal to 2015 ± 510, 2884 ± 505, and 4154 ± 233 milligrams of calcium carbonate per liter (mg CaCO3/L) at influent COD concentrations of 10,000, 20,000, and 30,000 mg/L, respectively, and in effluent, they were 2536 ± 336, 3379 ± 639, and 4377 ± 325 mg CaCO3/L, respectively. The amount of alkalinity in the effluent increased compared with the alkalinity in the influent. The results show that the amount of alkalinity in the influent and effluent was similar, and the alkalinity enhancement was lower when the filling ratio was increased from 10% to 20%, and 20% to 30%. Comparisons of the results from zeolite with and without biofilm showed that, in cases of zeolite with biofilm, the amounts of silica and oxygen decreased and the amount of carbon increased, and it showed the formation of biofilm on the surface of zeolite. In addition, the absence of sodium in the zeolite with the biofilm indicated that sodium was exchanged with ammonium ions. According to the results, zeolite can be used in anaerobic reactors as a medium, and it also reduces fluctuations in pH and alkalinity at different organic loading rates, providing a normal range for anaerobic treatment.  相似文献   
6.
快腐剂对畜禽粪便堆肥过程中腐熟度的影响   总被引:5,自引:0,他引:5  
以牛粪、菌糠和鸡粪等为材料按照两种比例调配为混合基质,在添加或不添加快腐剂的条件下在发酵桶中进行为期38 d的堆肥发酵实验,通过对发酵产物的温度、p H值、总有机碳、C/N、硝铵态氮含量和种子发芽指数等指标变化的研究,揭示了快腐剂对发酵过程的影响。结果表明,虽然快腐剂对有机物料的温度、C/N比无显著的影响,但可以促进铵态氮向硝态氮的转化,在16 d时使发酵产物NH+4-N/NO-3-N比值降为0.15,达到腐熟标准(0.16);提升种子发芽指数,在腐解29 d时使种子发芽指数达到82.76%,达到完全腐熟指标(0.8),比不添加快腐剂的处理提前了4 d左右。快腐剂的作用效果受腐解物料配比的影响。  相似文献   
7.
添加炭基材料对蔬菜废物好氧堆肥进程和腐熟度的影响   总被引:3,自引:0,他引:3  
以蔬菜废弃物辣椒秸秆和树叶为堆肥原料(CK),采用密闭式好氧堆肥工艺,研究了添加5%木本泥炭(T1)、5%活性炭(T2)和10%木本泥炭(T3)等炭基材料对堆肥p H、EC、CO2累积量、物料损失率、T值、C/N和发芽率指数的影响。结果显示,T2处理的p H在60 d后维持在8~9之间;EC值随着堆肥进行呈现先下降后升高再下降的趋势,最终CK、T1、T2和T3处理的EC值(m S/cm)分别降低了1.02、0.76、0.33和0.48;T2和T3处理的CO2累积量一直高于其他处理;所有处理的物料损失率均在20%以上;4个处理堆肥产品的T值分别为0.56、0.65、0.68和0.69;堆肥产品的发芽率指数分别为63.2%、69.3%、93.5%和86.1%。T值和发芽率指数显示T2和T3处理达到了腐熟阶段。结果表明,在蔬菜堆肥处理中添加炭基材料可改善堆肥产品的理化性质,加速堆肥物料的分解,有效地缩短堆肥周期和提高堆肥产品的腐熟度。  相似文献   
8.
Applying manure compost not only results in zinc accumulation in the soil but also causes an increase in zinc mobility and enhances zinc leaching. In this study, the physical and chemical characteristics of zinc, zinc profiles, and zinc balance were investigated to characterise the fate of zinc in fields where the quality and amount of pig manure compost applied have been known for 13 years. Moreover, we determined zinc fractionation in both 0.1 mol L?1HCl-soluble (mobile) and -insoluble (immobile) fractions. Adsorption of zinc in the soil was enhanced with increasing total carbon content following the application of pig manure compost. The 159.6 mg ha?1 year?1manure applied plot (triplicate) exceeded the Japanese regulatory level after only 6 years of applying pig manure compost, whereas the 53.2 mg ha?1 year?1 manure applied plot (standard) reached the regulatory level after 13 years. The zinc loads in the plots were 17.0 and 5.6 kg ha?1 year?1, respectively. However, 5.9 % and 17.2 % of the zinc loaded in the standard and the triplicate pig manure compost applied plots, respectively, were estimated to be lost from the plough layer. Based on the vertical distribution of mobile and immobile zinc content, a higher rate of applied manure compost caused an increase in the mobile zinc fraction to a depth of 40 cm. Although the adsorption capacity of zinc was enhanced following the application of pig manure compost, a greater amount of mobile zinc could move downward through the manure amended soil than through non manure-amended soil.  相似文献   
9.
木薯渣堆肥及其对难溶性磷的活化试验研究   总被引:1,自引:1,他引:0  
试验以干鸡粪、米糠、堆肥返料作调理剂,同时加入不同含量的磷矿粉,对木薯渣进行好氧堆肥,研究木薯渣堆肥过程中堆肥理化性质的变化及木薯渣堆肥对难溶性磷的活化作用。试验设置磷矿粉加入量10%(T1)、15%(T2)、20%(T3)和不加磷矿粉(CK)四个处理,干鸡粪、米糠、堆肥返料的添加量均为10%、15%和20%。在堆肥过程中,四个处理均在55℃以上高温持续了25d,超过了国家规定的标准。在堆肥结束时,各处理水分含量均降至30%左右,pH升高至弱碱性,淀粉降解率均在90%以上,水溶性碳(DOC)含量均降至10g.kg。以下,达到了基本腐熟的标准。证明木薯渣通过堆肥能达到稳定无害化状态。在堆肥结束时,T1、T2、T3有效磷增加量分别为12.58、12.81、12.96g.kg-1,对磷矿粉的活化率分别为23.53%、17.07%、14.50%,T1活化效果最好。研究结果表明木薯渣堆肥对难溶性磷有一定的活化作用,可为解决堆肥资源化产品中植物可利用磷含量偏低的难题开拓一条生物学途径:  相似文献   
10.
Abstract

A laboratory pot experiment was conducted to study the effect of amending soil with four different sources of organic matter on the degradation rate of α and β endosulfan isomers. Poultry by-product meal, poultry manure, dairy manure, and municipal solid waste compost were cured, dried, ground (<1 mm) and thoroughly mixed with a calcareous soil at a rate of 2% and placed in plastic pots. Endosulfan was added at the rate of 20 mg kg?1. The moisture level was kept near field capacity and the pots were kept at room temperature. Soil sub-samples, 100 g each, were collected from every pot at days 1, 8, 15, 22, 29, 43, and 57 for the measurement of endosulfan isomers. Endosulfan residues were extracted from the soil samples with acetone. The supernatant was filtered through anhydrous sodium sulphate, 5 mL aliquot was diluted to 25 mL with hexane, mixed well, and then two sub-samples from the filtrates were analyzed for α and β endosulfan isomers by gas chromatography. The results indicated that the half-life (T ½) of α-endosulfan in the poultry by-product meal treatment was 15 days compared to about 22 days in the other treatments. The T ½ of β-endosulfan was 22 days in the poultry by-product meal treatment and followed a bi-phasic pattern, 57 days in the municipal solid waste compost treatment and the extrapolated T ½ was about 115 days for the other three treatments.  相似文献   
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