攀枝花硫钴精矿浸出液净化试验研究

本文介绍了攀枝花硫钴精矿浸出液的净化试验研究。一次除铁采用先将亚铁氧化成三价铁后再调pH值的方法。沉淀氢氧化钴时可分离部分Ca,Mg,Mn等杂质。沉淀的氢氧化钴中还含有一些杂质,需要进一步除去。用硫酸溶解后,再用黄钠铁矾法二次除铁,P204萃取除去其它杂质。     

Leachate valorization in anaerobic biosystems: Towards the realization of waste-to-energy concept via biohydrogen,biogas and bioelectrochemical processes

Leachate generated in landfills is considered as a hazardous waste stream due to its composition and needs adequate treatment for environmental protection purposes. Nonetheless, a contemporary technology should not only be able to deal with its degradation, but at the same time, recover energy in various forms. Such valorization approaches with priority on these dual-aims are potentially those that rely on anaerobic biosystems. In the literature, processes considered on that matter include fermentative, digestive and bioelectrochemical set-ups to deliver energy-carriers such as biohydrogen (DF), biogas (AD) and electricity (BES), respectively. Moreover, to enhance the global efficiency of leachate utilization, it has been recently trending to develop integrated options by combining these systems (DF, AD, BES) into a cascade scheme. In this review, it is intended to give an insight to the research activities realized in these fields and show possible directions towards the better exploitation of leachate feedstock under anaerobic conditions.     

Fenton-SBR工艺对渗滤液溶解性有机物的去除特性

通过Fenton-SBR组合工艺对渗滤液溶解性有机物处理效果的研究,分析了溶解性有机物分子量分布及其3组份HA、FA及HyI的变化特性。研究发现,组合工艺对渗滤液中以COD、DOC及UV254表示的溶解性有机物总去除率分别为79.1%、73.6%和92.9%;对各分子量分布区间的去除效果较好,除10~4 ku分子量区间外,其余分子量区间COD去除率均在80%以上;同时,组合工艺对渗滤液DOM3组份的去除率为HAFAHyI,对3组份以UV254、COD和DOC表征的各指标去除率为UV254CODDOC。     

Preliminary Analysis Of Heavy Metals In The Kahrizak Landfill Leachate: A Conceptual Approach

No data have been published on the leachate quality for the Kahrizak landfill site, including heavy metal concentrations. Therefore concentrations of Cu, Zn, Pb, Cd, Ni, Co, Fe and Mn were measured in four fresh and older leachate samples during a 10 months period. Conceptually, heavy metals can be considered to be present in three phases: ( a ) Dissolved; ( b ) adsorbed onto suspended solids; and ( c ) adsorbed onto the suspended solids with particle sizes less than 0.45 w m. A method is proposed in this paper to measure the concentrations of heavy metals in each of the three phases. Other samples were analyzed for phases ( a ) and ( b ). Fresh leachate samples with lower pH values had higher dissolved concentrations of heavy metals than the older leachate samples with higher pH values. Particulate heavy metal concentrations were slightly lower at higher pH values.     

Landfill evolution and treatability assessment of high‐strength leachate from msw with high organic and moisture content

The generation of contaminated leachate remains an inevitable consequence of the practice of solid waste disposal in landfills. The collection and treatment of leachate have become common practice in order to prevent environmental pollution. Leachate treatment is highly dependent on the quality of leachate, which in turn is influenced by various factors including waste composition and operational procedures. This paper investigates the treatability of high‐strength leachate from pre‐sorted and baled municipal solid waste characterized by high organic and moisture content. For this purpose, waste disposal and leachate generation rates were monitored. Leachate samples were collected and analysed for selected indicators including BOD, COD, pH, and NH₄‐N and a pilot scale treatment plant with coagulation, precipitation and sequential batch biological reactors was constructed to evaluate the feasibility of leachate treatment. Concentration levels were related to biological activity within the landfill and the results indicated that (1) pre‐sorting and baling of the waste did not hinder waste stabilization; and (2) the high organic and moisture contents resulted in an extremely strong leachate, particularly at the onset of biodegradation processes, which can affect the leachate treatment facility. The effectiveness of the pilot plant in treating the leachate exceeded 90% using COD and NH₄‐N as indicators.     

Leachate treatment by the reverse osmosis system

The DT-Module system for landfill leachate treatment installed at Yachiyo Town in the Kanto District of Japan was put into service in April 1999. The system, which is equipped with a disc-tube type reverse osmosis (RO) membrane module called the DT-Module, has been operating satisfactorily for more than two and a half years, producing very-high-quality product water, after treating very-high-salinity water with high-scaling ions. On the other hand, in Japan, the dioxin problem has become increasingly severe, and development work for dioxin removal incorporated in leachate treatment has also been requested. The DT-Module system showed excellent performance in removing dioxins from leachate. For dioxins in sludge from the settling basin and dried salt from the concentrate of the RO system, successful destruction data were obtained by furnace system heating in an oxygen-deficient atmosphere. The removal rate of dioxins by the DT-Module system and the destruction rate by the furnace were both higher than 99.9%. By applying the DT-Module system together with the furnace system, an excellent leachate treatment and a complete dioxin removal and destruction system have become available for leachate from landfills depositing incineration residue-containing dioxins.     

CANON工艺处理垃圾渗滤液中的高浓度氨氮

CANON工艺是在限氧的条件下 ,利用完全自养性微生物将氨氮和亚硝酸盐同时去除的一种方法 ,从反应形式上看 ,它是SHARON和ANAMMOX工艺的结合 ,因此可以在同一个反应器中进行。深圳市下坪固体废弃物填埋场渗滤液处理厂通过一年多的运行 ,发现溶解氧控制在 1mg/L左右 ,进水氨氮 <80 0mg/L ,氨氮负荷 <0 4 6kgNH+ 4/(m3·d)的条件下 ,可以利用SBR反应器实现CANON工艺 ,氨氮的去除率 >95 % ,总氮的去除率 >90 %。     

沉淀法回收氧化酸浸—络合法浸出液中的锑和铜

广西河池某冶炼厂氧化酸浸—络合法浸出获得的含锑、铜浸出液中锑、铜含量分别为538.51 mg/L、395.91 mg/L。对该浸出液进行水解沉淀法回收锑,沉锑残液Na2S沉淀法回收铜的试验研究,结果表明:在搅拌强度为150 r/min、反应温度为56℃、反应时间为20 min、反应终了pH=3.15条件下水解沉锑,可获得锑品位、沉淀率分别为10.35%、98.23%的沉锑产品;沉锑残液在Na2S添加量为2.5 g/L、搅拌强度为150 r/min、反应温度为50℃条件下反应10 min,反应完全后静置20 min进行过滤,可获得铜品位、沉淀率分别为36.92%、98.38%的沉铜产品。试验结果证明分步沉淀法是回收该浸出液中锑、铜的有效方法。     

Mature landfill leachate treatment from an abandoned municipal waste disposal site

We investigated treatment techniques for the leachates derived from an abandoned waste disposal landfill facility known as Nan Ji Do in Seoul, Korea. To this end, the general characteristics of those leachates were carefully examined. The feasibility of leachate handling techniques was then examined through an application of both offand on-site processes as a combination of direct treatment methods and/or pretreatment options. They include operation of such systems or methods as: (1) activated sludge process, (2) adsorption-flocculation methods, and (3) anaerobic digestion. When the fundamental factors associated with the operation of an activated sludge process were tested by a simulated system in the laboratory, those applications were found to be efficient at leachate addition of up to 1%. Application of adsorption/precipitation method was also tested as the pretreatment option for leachates by using both powdered activated carbon (PAC) as adsorbent and aluminum sulfate (alum) as flocculant. Results of this test indicated that the removal of chemical oxygen demand (COD) was optimized at PAC and alum contents of 100 to 300 mg/L, respectively. In addition, an anaerobic digester also examined the effect of leachate components on the rate of anaerobic digestion. According to our study, treatment and pretreatment options investigated were, in general, effective enough to reduce the rate of organic loading and the occurrences of hazardous incidents.     

生活垃圾填埋场渗滤液调节池容积计算探讨

云南省在建或已建的城市生活垃圾卫生填埋场已超过100座.生活垃圾填埋场产生的渗滤液如不妥善处置,将造成较大的环境问题.介绍了垃圾渗滤液调节池计算的理论及方法,对整个计算过程进行了详细分析,并通过工程实例给予进一步说明,可供同行借鉴.