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111.
电解法处理含镍废水及纯镍的回收 总被引:1,自引:0,他引:1
雷英春 《城市环境与城市生态》2009,(3)
采用电解回收法处理Ni2+含量为2g/L的废水,在阴极回收纯镍。研究了电解电流、极距、NH4Cl浓度、pH值等因素对Ni2+去除率、槽压、阴极能耗的影响,得出最优工艺参数为:温度20℃,电解时间20min时、电解电流300mA,极距15mm,NH4Cl浓度5g/L,pH值8.0,该条件下Ni2+去除率为96.926%,槽压16.21V,阴极能耗22.418kW.h/kg,在阴极可得到沉积6.45μm厚的镍板。 相似文献
112.
本文对小型造纸厂的碱回收在技术上和经济上的可行性进行了分析,作出了当前是中、小型造纸厂搞碱回收的有利时机的初步评价。 相似文献
113.
回收PTA废料生产增塑剂 总被引:3,自引:0,他引:3
介绍了扬子石化公司PTA生产过程中所排各种废料的分离提纯及回收利用,对难以回收的氧化残渣的分离回收和利用作了重点论述。提供了用所回收的TA和混合苯二甲本乡生产剂的工艺流程和工艺参数。 相似文献
114.
115.
攀钢烧结烟气脱硫技术研究 总被引:10,自引:1,他引:10
介绍了攀钢烧结烟气的特点,SO2的来源。根据国内外烟气脱硫技术现状, 提出了攀钢烧结烟气脱硫的技术要求。 相似文献
116.
文章在介绍我国化学工业排放三废的严峻现状后,阐述了通过工艺改造和综合回收途径来推进三废资源化的技术对策,以及从宏观和微观上看深化三废资源化的意义和光明前景。 相似文献
117.
The article describes the historical development of water tariff policy in Tanzania from the colonial times to present. After
gaining independence, the country introduced “free” water policy in its rural areas. Criticism against this policy was expressed
already in the 1970s, but it was not until the late 1980s that change became unavoidable. All the while urban water tariffs
continued to decline in real terms. In rural and periurban areas of Tanzania consumers often have to pay substantial amounts
of money for water to resellers and vendors since the public utilities are unable to provide operative service. Besides, only
a part of the water bills are actually collected. Now that the free water supply policy has been officially abandoned, the
development of water tariffs and the institutions in general are a great challenge for the country. 相似文献
118.
本文介绍了关于洗涤剂中磷对环境影响的两种典型观点和解决的办法,并从经济和环境的角度进行全面的分析,得出合理的结论和建议。 相似文献
119.
Ryo?ShojiEmail author Takanori?Miyazaki Takashi?Niinou Mikio?Kato Hiroshi?Ishii 《Journal of Material Cycles and Waste Management》2004,6(2):142-146
We have successfully prepared a bead-type adsorbent from two materials with different adsorption characteristics. Heavy metals were removed by greatly swollen egg shell membrane-conjugated chitosan beads. The egg shell membrane accumulated and removed precious metal ions from a dilute aqueous solution with a high affinity in a short contact time. Experiments suggested that chitosan beads could take up gold ions with great capacity and selectivity by conjugation with egg shell membrane. Under certain conditions, the selective removal of gold and copper in a mixture of gold and copper ions by egg shell membrane-conjugated chitosan beads was 100% and 2%, respectively. Egg shell membrane-conjugated chitosan beads can be seen as a promising material to recover gold in wastewater from various industries, such as electroplating. 相似文献
120.
Saber A. El-Shafai Fatma A. El-Gohary Fayza A. Naser P. van der Steen Huub J. Gijzen 《The Environmentalist》2007,27(2):287-302
An integrated system, consisting of Up-flow Anaerobic Sludge Blanket (UASB)-duckweed-tilapia ponds was used for recovery of
sewage nutrients and water recycling. A UASB reactor with 40 liter working volume was used as pre-treatment unit followed
by a series of three duckweed ponds for nitrogen recovery. The treated effluent and duckweed biomass was used to feed fishponds
stocked with Nile tilapia (Oreochromis niloticus). The UASB reactor was fed with raw, domestic sewage at 6 h hydraulic retention time. The three duckweed ponds were stocked
with Lemna gibba and fed with UASB effluent at 15 days hydraulic retention time. Nitrogen recovery from UASB effluent via duckweed biomass
represented 81% of total nitrogen removal and 46.5% from the total nitrogen input to the system. In subsequent fishponds the
nitrogen recovery from duckweed as fish feed was in the range of 13.4–20%. This nitrogen in fish biomass represented 10.6–11.5
g N from the total nitrogen in the raw sewage fed to the UASB reactor. The growth performance of tilapia (Oreochromis niloticus) showed specific growth rates (SGR) in the range of 0.53–0.97. The range of feed conversion ratio (FCR) and protein efficiency
ratio (PER) were 1.2–2.2 and 2.1–2.28, respectively. The results of the experiments showed total fish yield and net fish yield
in the range of 17–22.8 ton/ha/y and 11.8–15.7 ton/ha/y respectively. In conclusion UASB-duckweed-tilapia ponds provide marketable
by-products in the form of duckweed and fish protein, which represent a cost recovery for sewage treatment. 相似文献