水解酸化/生物接触氧化工艺处理印染废水应用实例

介绍了采用水解酸化/生物接触氧化工艺处理印染废水的应用实例。运行结果表明,该工艺能有效去除废水中的污染物,当进水CODCr为1025mg/L、BOD5为343mg/L、SS为421mg/L、色度为500倍时,处理后出水CODCr、BOD5、SS分别可达到43、16、32mg/L,色度可降低到19倍,去除率分别为95.8%、95.3%、92.4%、96.2%。经该工艺处理后的出水水质稳定,并达到了《污水综合排放标准》(GB8978—1996)一级标准。     

气浮—ABR—生物接触氧化处理乳制品废水

采用气浮—ABR—生物接触氧化工艺处理乳制品废水。在进水CODCr为1 400 mg/L、BOD5为840 mg/L、SS为500 mg/L和pH=4.5的条件下,CODCr和BOD5的去除率分别达到95%和98%。出水CODCr、BOD5、SS和pH均达到《污水综合排放标准》(GB 8978—1996)一级排放要求。     

EGSB/MBR处理脂类生产废水的改扩建工程

采用厌氧污泥膨胀床/膜生物反应器为主体的工艺处理脂类生产废水。工程运行结果表明:原水进水COD为8 216.34 mg/L,BOD5为557.16 mg/L,SS为418.2 mg/L,色度为205倍经过处理后,出水COD为92.85 mg/L,BOD5为16.63 mg/L,SS为6.32 mg/L,色度为13.71倍。出水达到《污水综合排放标准》(GB 8978—1996)的一级标准。     

水解酸化-生物接触氧化-气浮工艺处理印染废水

采用水解酸化-生物接触氧化-气浮工艺处理印染废水,结果表明,当进水CODCr、BOD5、SS的质量浓度分别为450～900、100～220、250～370 mg/L,pH值为7～11,色度为450～650倍时,出水CODCr、BOD5、色度、SS等各项指标均能达到《纺织染整工业水污染物排放标准》(GB 4287-92)中的一级排放标准,处理成本为0.805元/t。     

化工工业园污水的集中处理工程

化工、染料工业生产废水含有大量难降解有机物,可生化性差,水质水量变化频繁,采用A/O活性污泥结合接触氧化法集中处理化工工业园生产废水,工程运行结果表明,在进水SS,CODCr,BOD5和苯胺类的质量浓度分别为139,778,156和6.40mg/L,色度为612倍的情况下,排水的SS,CODCr,BOD5和苯胺类的质量浓度分别为19,193,4.88和0.084mg/L,色度为80倍,废水经处理后基本可达到排放标准。     

膜生物反应器处理中药加工厂生产废水

利用膜生物反应器处理中药加工厂生产废水,设计处理能力48 m3/d,在进水CODCr和BOD5的质量浓度分别为4 120、2 060 mg/L,色度为1 000倍时,经处理后,出水CODCr和BOD5的质量浓度分别为100和45mg/L,色度小于60倍,去除率分别达97.6%、97.8%和94.4%,且出水稳定,低于广东省地方标准《水污染物排放限值》(DB44/26-2001)中第二时段二级排放标准。     

气浮+SBR+液氯消毒处理工业园废水技改探讨

采用气浮+SBR+液氯消毒工艺处理小蓝工业园废水,一期工程技改后设计规模为25000m3/d,进水水质为COD 600mg/L,BOD5220mg/L,SS 200mg/L,色度80倍,pH值6.5-8.5;经该工艺处理后,出水水质为COD≤100 mg/L,BOD5≤30mg/L,SS≤30mg/L,色度40倍,pH值6-9,达到了国家《城镇污水处理厂污染物排放标准》(GB18918-2002)二级排放标准的要求。     

厌氧-好氧-强氧化组合工艺处理酱油废水工程实例

采用改良型UASB-氧化沟-强氧化组合工艺处理酱油废水,在进水CODCr、BOD5、SS、NH3-N的质量浓度分别为2 080、1 036、360、62.3 mg/L,色度为176倍时,出水CODCr、BOD5、SS、NH3-N的质量浓度分别为45、14.6、27、6 mg/L,色度为6倍,各项指标均达到DB 44/26—2001广东省《水污染物排放限值》中第二时段一级标准的要求。运行结果表明,该工艺运行稳定,处理效果好,耐冲击负荷能力强,高效且节能。     

铁碳微电解-SBR工艺处理己内酰胺废水试验研究

采用铁碳微电解-SBR工艺处理己内酰胺废水,考察了pH值、铁碳质量比、反应时间等因素对铁碳微电解处理效果的影响。试验结果表明:在进水CODCr的质量浓度为2 000~3 000mg/L,BOD5的质量浓度为1 000~1 500 mg/L,NH3-N的质量浓度为150 mg/L左右,色度约为120倍的条件下,当进水pH值为3,铁碳质量比为4∶1,反应时间为1.5 h时,铁碳微电解对CODCr、NH3-N、色度的去除率分别达到50.6%、41.8%、33.3%;己内酰胺废水经铁碳微电解-SBR工艺处理后,最终出水CODCr的质量浓度稳定在80 mg/L左右,BOD5的质量浓度稳定在15 mg/L以下,NH3-N的质量浓度小于15 mg/L,色度小于45倍,均达到GB 8978—1996《污水综合排放标准》中一级标准的要求。     

物化-厌氧水解-缺氧-生物接触氧化法-脱色处理调味品生产废水

本废水主要为调味品生产企业在生产过程中排放的生产废水。主要污染物为CODCr、SS、NH3-N、BOD5、色度等。本工程采用"物化+厌氧水解+缺氧+生物接触氧化法+脱色"工艺对该废水进行处理。工程自2011年08月投产至今,处理效果稳定,BOD5去除率大于98.3%,CODCr去除率大于96.4%,色度去除率大于93.3%,各项出水指标均可以达到相关的排放标准。     

Compact Swelling in Bi1.4Pb0.6Sr2Ca2Cu3.6Oy During the Formation of High-Tc Superconducting Phase

Compact swelling in Pb-doped Bi-Sr-Ca-Cu-O superconductor has been studied by observing the effects of the size of calcined powders, volatilization of materials, and sintering of high- T _c (2223) powders. The bulk density increases at the early stage of sintering, for about 20 h, and then decreases. Densification occurs when the low- T _c (2212) phase and a liquid phase exist, whereas dedensification occurs with the formation of the 2223 phase regardless of the presence of the liquid. Gas evolution from specimens does not appear to be responsible for compact swelling. Compact swelling is explained by anisotropic growth of thin, platelike 2223 grains in random orientation. When 2223 grains grow in a preferred direction, compact swelling is suppressed.     

Synthetic routes to nanoscale BxCyNz architectures

B_xC_yN_z nanoscale materials, hybrids of h-BN and graphite, have been recently synthesised using various techniques. Here, we present the latest advances in the synthesis and characterisation of B-C-N nanotubes and nanofibres. In particular, we focus on layered BC₂N, BN, BC and CN_x systems, reviewing their production methods as well as their structural and electronic properties. These materials may find important applications in the fabrication of nanotransistors, robust nanocomposites, conducting polymers, storage components and field emission sources.     

Microwave Dielectric Properties of CaTiO3-CaAl1/2Nb1/2O3 Ceramics Doped with Li3NbO4

The microwave dielectric properties of CaTi_{1− x} (Al_1/2Nb_1/2) _x O₃ solid solutions (0.3 ≤ x ≤ 0.7) have been investigated. The sintered samples had perovskite structures similar to CaTiO₃. The substitution of Ti⁴⁺ by Al³⁺/Nb⁵⁺ improved the quality factor Q of the sintered specimens. A small addition of Li₃NbO₄ (about 1 wt%) was found to be very effective for lowering sintering temperature of ceramics from 1450–1500° to 1300°C. The composition with x = 0.5 sintered at 1300°C for 5 h revealed excellent dielectric properties, namely, a dielectric constant (ɛ_r) of 48, a Q × f value of 32 100 GHz, and a temperature coefficient of the resonant frequency (τ_f) of −2 ppm/K. Li₃NbO₄ as a sintering additive had no harmful influence on τ_f of ceramics.     

Preparation and properties of poly(Nε,Nε-dicarboxymethyl-l-lysine)

A new ampholytic homopolypeptide, $\text{poly}\text{(N}{}^{\mathrm{\epsilon }}\text{,N}{}^{\mathrm{\epsilon }}\text{-}\text{dicarboxy-methyl-}\text{l}\text{-lysine}\text{)}$, which has one tertiary amino and two carboxyl groups in the side chain has been derived from a hydrochloride salt of poly(L-lysine). The polymer in aqueous solution seems to be in the coil form with locally extended structure (LES) at neutral pH. In both the acidic and alkaline regions, the molar ellipticity of the polymer changes as a result of change in net charge on the side chain. The conformational changes may be from the coil with LES to other coiled forms. 5–7 M NaClO₄ and 80% aqueous methanol induce the α-helix in the polymer at neutral pH. Divalent cations, Cu²⁺ and Ca²⁺, do not induce any remarkably ordered structures such as α-helix or β-structure in the polymer in aqueous solution at any pH. Ultraviolet absorption studies show an absorption peak of the polymer-Cu²⁺ complex near 240 nm. Dependence of the peak intensity on pH at various q values ($\text{q =}\text{[}\text{Cu}{}^{\mathrm{2+}}\text{]}\text{[}\text{residue}\text{]}$) indicates the two steps of the complex formation. At q less than 0.64, the formation is described only with the first step. An average coordination number for Cu²⁺ at the first step was calculated to be about 2 by the method of Mandel and Leyte. The association constant of Cu²⁺ with the residue at the step was determined from the absorption data to be far smaller than that for the Cu²⁺-EDTA complex. The second step of the formation occurs in the case of large q but the absorption data for the second step cannot be obtained exactly due to precipitation.     

Structure Evolution from Pb(Mg1/3Nb2/3)O3 to La(Mg2/3Nb1/3)O3

The crystal structure of lanthanum-modified lead magnesium niobates having composition (Pb_{1− x} La _x ) (Mg_{(1+ x )/3}-Nb_{(2− x )/3})O₃ with X = 0 to 1 was investigated by X-ray powder diffraction. It was found that the fundamental reflections from perovskite structure remain in the whole range of composition. The superlattice reflections from the A(B'_1/2-B"_1/2)O₃ ordered structure are also well preserved for La content greater than 50 at.%; however, a series of extra peaks of mixing indices appears, with intensities gradually enhanced with the increase of La content. For the complete substitution of Pb by La, a splitting of some reflections can be observed in the diffraction pattern. The results indicate that the crystal structure evolves continuously with the La content, from disordered cubic perovskite of space group Pm 3 m for X = 0, to ordered cubic perovskite of space group Fm 3 m for X = 0.5, distorted cubic perovskite of space group Pa 3 for 0.5 < X < 0.9, and finally to a rhombohedral perovskite, possibly belonging to the space group R 3 , for X ≥ 0.9. In the evolution of structure, a linear reduction of the lattice constant of the perovskite cell from 4.048 to 3.964 Å was observed.     

Dielectric-State Analysis in Solid-Solution Pb(Yb1/2Ta1/2)O3–Pb(Lu1/2Nb1/2)O3

The structure and temperature dependence of complex lead perovskite dielectrics were investigated for the system (1 − x )Pb(Yb_1/2Ta_1/2)O₃– x Pb(Lu_1/2Nb_1/2)O₃. Superlattice reflections for the compositions 0.8 < x < 1.0 were observed by X-ray diffractometry, and the temperature-composition dielectric-state diagram was determined. In the present study, the disordered middle composition, with 0.2 < x < 0.8, showed a diffuse paraelectric–ferroelectric phase transition, whereas the ordered end compositions, with 0 ≤ x < 0.2 and 0.8 < x ≤ 1.0, revealed successive sharp paraelectric–antiferroelectric and weak antiferroelectric–ferroelectric phase transitions. The dielectric state was confirmed by examining the variation of polarization ( P ) with electric field ( E ).