焦化废水深度处理技术

 焦化废水含有大量有机污染物和有毒无机物,成分十分复杂,污染物色度高,属较难降解的高浓度有机工业废水。经预处理和生化处理后的焦化废水存在COD、氨氮、总氮及氰化物不达标的问题。通过高级氧化法、混凝沉淀法、吸附法、膜分离法、生物化学法以及组合工艺等深度处理方法可以使出水满足新标准的要求。介绍了目前国内焦化废水深度处理的工艺现状以及展望。     

危险废物处理处置中的废水处理设计

从废水的水质、处理工艺和单体构筑物等方面介绍了某危险废物处理处置中的废水处理设计。该项目采用物化处理+生化处理+深度处理的组合工艺,具有效果好、出水水质稳定等优点,出水可满足《污水综合排放标准》(GB 8978-96)一级标准的要求。     

鞍钢鲅鱼圈焦化废水深度处理工艺实践

针对鞍钢股份有限公司鲅鱼圈钢铁分公司焦化废水A2/O生物系统处理后出水COD、总氰及氨氮仍很难达标,生物处理段处理效果不好等问题,对臭氧催化氧化及电絮凝焦化废水深度处理工艺进行了研究。工业实践表明,将原A2/O生物系统出水经臭氧催化氧化深度处理后,COD和总氰化物去除率分别达到66%和84%,出水指标达到设计要求,环境效益显著。     

Nitrification∕Denitrification in Intermittent Aeration Process for Swine Wastewater Treatment

A continuous-flow intermittent aeration (IA) process has been studied for nitrogen removal from anaerobically digested swine wastewater with high ammonium content. High nitrogen removal efficiency of average 91% total Kjeldahl nitrogen and 92% NH4-N was achieved in an IA system with an alteration of 1-h aeration and 1-h nonaeration. Nitrification and denitrification were found to be responsible for the nitrogen removal in the system. Nitrite and nitrate in the effluent were less than 1.0 mg∕L and 8.0 mg∕L, respectively. The specific nitrification and denitrification rates of the single-sludge IA culture were determined through batch experiments as 2.79–3.70 mgNO3-N∕g volatile suspended solids-h and 0.59–1.03 mgNO3-N∕g volatile suspended solids-h, respectively. In the IA process, the aeration period created favorable conditions for nitrifying bacteria (dissolved oxygen = 4–6 mg∕L and oxidation-reduction potential = 80–100 mV), while the nonaeration period provided good environment for denitrifying bacteria (dissolved oxygen < 1 mg∕L and oxidation-reduction potential as low as 0 mV). Ammonia volatilization in the IA process was negligible (<0.008%). Denitrification activity in the IA process prevented nitrate from accumulation and significant pH change in the system, which is critical for nitrogen removal from swine wastewater with high ammonium content.     

镍钼矿冶炼废水的处理

对常用工艺进行比选,采用石灰-亚铁絮凝共沉淀法处理镍钼矿冶炼废水。针对该废水的特点,设计了一套污水处理工艺流程。工程实际运行结果表明,废水经该工艺流程处理后,砷、镍等主要污染物去除率可达99%以上,出水水质可达到《污水综合排放标准》(GB8978-1996)中的一级标准。该工艺运行稳定,操作简便,处理效率高,出水水质好。     

Optimization of Biological Nutrient Removal in a Membrane Bioreactor System

The main objective of the present study is to develop a modified membrane bioreactor (MBR) system for the treatment of municipal wastewater for the enhanced biological removal of nitrogen (N) and phosphorus (P) simultaneously with the ultimate goal of optimizing the two processes. The paper will address the implementation and optimization of the MBR process with respect to biological characteristics, operational performance, and effluent quality. The system utilizes anoxic P uptake and nitrification–denitrification in a MBR. Following optimization, the system achieved 99% chemical oxygen demand (COD), 98.4% NH3–N, 77.5% TN, and 96.3% P removal producing effluent biological oxygen demand, COD, NH3–N,NO3–N,NO2–N, and P of <3, 3, 0.4, 5.8, 0.050, and 0.18?mg/L, respectively.     

某锑矿含重金属废水的处理

对锑矿废水处理常用工艺进行比选后,采用石灰-铁盐联合化学中和沉淀法处理该类型废水。工程实际运行结果表明,通过该工艺处理后,出水水质可达到《污水排放综合标准》(GB8978-1996)中一级标准的要求,锑的浓度符合《工业废水中锑污染物排放标准》(DB43/350-2007)中限值。该工艺处理效果稳定可靠,运行操作简单,出水水质达标。     

短程硝化-厌氧氨氧化处理焦化废水的研究

采用短程硝化-厌氧氨氧化生物脱氮新工艺进行焦化生产废水处理的研究，详细讨论了各个处理环节的运行情况和效果。通过新处理工艺的焦化废水各出水指标均达到国家排放标准一级，总氮去除率达到70％～80％，克服了传统硝化反硝化生物脱氮技术的缺陷，有效地避免了氮素对水体的污染。     

Treatment of Drilling Wastewater by Combined Coagulation-Ultraviolet/Fenton-Pressurized Biological Processes

An integrated technique containing coagulation, ultraviolet/Fenton oxidation, and pressurized biological processes was provided for the treatment of wastewater generated from drilling operation where sulfonated muds were used. Ultraviolet/Fenton oxidation process was used to improve biodegradability of effluent after coagulation [assessed through a ratio of biological oxygen demand to chemical oxygen demand (COD) (B/C) index]. Pressurized biological experiments were used to further remove COD so as to meet the wastewater discharge standard. The results showed that coagulation pretreatment could help remove most of CODs (70–80%) in drilling wastewater. A 57% reduction in COD was obtained in the ultraviolet/Fenton oxidation process with 0.8 Qth H2O2 (in 30 min), and the biodegradability was significantly improved (B/C was increased from 0.03 to 0.47). The pressurized biological process could help speed up the reaction process with a saved aeration time of 66.7% under a system pressure of 0.2 MPa (in comparison with the condition of a normal pressure). The overall COD removal efficiency was about 95% and the COD level in the final effluent was less than 100 mg/L, which satisfied the wastewater discharge standard.     

Influence of COD:N:P Ratio on Nitrogen and Phosphorus Removal in Fixed-Bed Filter

This study examined the effects of COD:N:P ratio on nitrogen and phosphorus removal in a single upflow fixed-bed filter provided with anaerobic, anoxic, and aerobic conditions through effluent and sludge recirculation and diffused air aeration. A high-strength wastewater mainly made of peptone, ammonium chloride, monopotassium phosphate, and sodium bicarbonate with varying COD, N, and P concentrations (COD: 2,500–6,000, N: 25–100, and P: 20–50 mg/L) was used as a substrate feed. Sodium acetate provided about 1,500 mg/L of the wastewater COD while the remainder was provided by glucose and peptone. A series of orthogonal tests using three factors, namely, COD, N, and P concentrations, at three different concentration levels were carried out. The experimental results obtained revealed that phosphorus removal efficiency was affected more by its own concentration than that of COD and N concentrations; while nitrogen removal efficiency was unaffected by different phosphorus concentrations. At a COD:N:P ratio of 300:5:1, both nitrogen and phosphorus were effectively removed using the filter, with removal efficiencies at 87 and 76%, respectively, under volumetric loadings of 0.1?kg?N/m3?d and 0.02?kg?P/m3?d.     

Performance of a Combined Natural Wastewater Treatment System in West Texas

A study of performance of a combined natural wastewater treatment system was conducted in an arid and semiarid area of West Texas from October 2005 to September 2007. This study investigated the organic matter and nitrogen removal capability in a municipal wastewater land application system following a pond system. Municipal wastewater from the city of Littlefield, Tex. was pretreated by a pond system, and the secondary wastewater effluent from the pond system was surface applied to sprayfield at the wastewater treatment plant and the city farm. The 16 lysimeters were installed in situ to collect the leached water passing the grass root zone. The water samples were taken from the storage pond and the lysimeters for analysis of chemical oxygen demand (COD), total nitrogen, nitrate nitrogen, and ammonia nitrogen. The data show that the pond system played an important role in the treatment. The pond system pretreated COD in the municipal wastewater to the range of 10 to 127 mg/L, total nitrogen to the range of 5 to 19 mg/L, nitrate nitrogen to the range of 2.4 to 8.2 mg/L, and ammonia nitrogen to the range of 0.01 to 6.4 mg/L. The average mass removals and cumulative mass removals were 94 and 96% for total nitrogen, 92 and 93% for nitrate nitrogen, and 96 and 100% for ammonia nitrogen, respectively. There was no potential nitrogen contamination to groundwater found during the research period. The study illustrated that this type of combined natural wastewater treatment system can be used to effectively treat and safely dispose municipal wastewater, and save freshwater used for agricultural irrigation in arid and semiarid area.     

钨及钴冶炼高氨氮废液处理的实践

有色金属冶炼中产生的大量废水中含有高浓氨氮、高浓盐类、重金属元素等污染物,必须妥善处置。文章结合某钨冶炼企业及某钴冶炼企业中对高氨氮废液的治理实践,探讨了采用四效降膜蒸发法及兼氧生化+好氧生化法组合工艺治理该类废液的途径。采用该方法可有效的解决含硫酸铵或氯化铵工业废液蒸发过程中能耗过高、设备腐蚀等技术难点,可实现废液达标排放或完全回用;年处理30万t高氨氮废液,可回收2万t硫酸铵及0.2万t氯化铵,实现氨氮废液的资源化。     

高浓度氨氮废水处理应用研究

本文介绍了用低污染或无污染清洁钼酸铵生产工艺改造传统工艺,彻底改变了钼酸铵传统工艺的“达标排放”氨氮治理模式,同时在氨氮治理方面开发新工艺、新过程、新装备,达到了环境、经济双重效益.     

Ion Exchange of Ammonium in Zeolites: A Literature Review

The objective of this review was to acquire knowledge concerning the ammonium ion exchange technique within the field of wastewater treatment. General concepts as well as details concerning the loading and the regeneration phases were included. Both chemical and biological regeneration processes were reviewed. Concerning ion exchangers, the study focused on different kinds of zeolites. The possibilities of employing the ion exchange technique for the recovery of nitrogen was also discussed. The study was carried out as a literature review. Conclusions from this study are that full-scale wastewater treatment plants that employ the ammonium ion exchange technique are scarce and few applications have been developed to recover ammonia nitrogen, for example, for agricultural purposes. Zeolites are somewhat heterogeneous because of natural variations of the minerals. Factors that influence the ammonium adsorption during the loading phase are well known. Biological regeneration has primarily been developed to decrease the brine consumption at regeneration or to improve the conventional nitrification-denitrification process. If the ion exchange technique is to be used to recover ammonium, both chemical and biological regeneration might be employed.     

New Integrated Processes for Treating Cold-Rolling Mill Emulsion Wastewater

 A large amount of oily wastewater is discharged during steel rolling in the steel industry, and the emulsion wastewater discharged during the steel cold-rolling mill contain a lot of non-degradable organic pollutants. However, the traditional treatments of oily wastewater can hardly work well to reach the discharge standards. There are two new techniques for emulsification wastewater treatment: the one is the integrated process of gas-energy-flocculation (GEF) and electrochemical catalytic oxidation (ECO) and membrane bioreactor (MBR); the other is the integrated process of ultra-filtration (UF) and ECO and MBR. Both of them are adopted to the continuous pilot test on the scale of 200L/h to 3000L/h. Moreover, every module of the combined techniques is analyzed. The operating parameters of every mould are investigated and the relationships between the operating parameters and CODCr removal efficiencies of the two integrated processes are evaluated. The experimental results have shown that almost all the oil and non-degradable organic substances are effectively removed with the effluent CODCr less than 30mg/L. The ultimate treated water quality could meet the requirement for productive reuse. What’s more, the integrated process of UF and ECO and MBR has a more stable effluent quality. Hence it can be widely used in a variety of industrial fields.     

铅冶炼含铊废水处理生产实践

铊(Tl)是一种剧毒的重金属元素,环境中的铊可被动植物吸附,通过食物链进入到人体内,进而造成人类健康风险.针对郴州某铅冶炼厂废水水质情况,进行相关改造,采用"稳定剂调整一生物制剂配合—絮凝分离"工艺对其进行深度处理,处理规模为7000 m3/d,进水Tl浓度0.06～0.15 mg/L,处理后出水Tl浓度＜0.005 ...     

New Integrated Processes for Treating Cold-Rolling Emulsion Wastewater

Two new integrated processes, gas-energy-management (GEM)—electrochemical catalytic oxidation (ECO)—membrane bioreactor (MBR) and ultrafiltration (UF)—ECO—MBR, in industrial-scale test for treating cold-rolling mill emulsion wastewater with water quantity of 200 L/h to 3000 L/h were studied. The former was put forward firstly and the latter was applied initially in this field. The operation conditions and mechanisms of each module in the integrated processes were analyzed and the influences of operational parameters of two processes on chemical oxygen demand (COD_Cr) removal efficiency were comparatively investigated. The test results showed that the ultimate water quality from the two processes after treatment could meet the requirement for reuse. However, the quality of effluent treated by GEM—ECO—MBR was more stable than that of UF—ECO—MBR.     

尾矿库氰渣淋溶废水深度处理工艺研究

针对黄金矿山尾矿库氰渣淋溶的低质量浓度含氰废水,采用OOT/OCT—BAF联合工艺进行处理。其试验结果表明,在进水总氰化合物为64.45 mg/L、硫氰酸盐为22.74 mg/L、COD为76.58 mg/L、铜为72.48 mg/L的条件下,当臭氧投加量为250 mg/L、臭氧投加量分流比为2∶1、BAF的废水停留时间为20 min、气水比为3∶1时,出水总氰化合物为0.02 mg/L、硫氰酸盐完全去除、COD为5.43 mg/L、铜为0.32 mg/L、氨氮为0.79 mg/L,出水达到《GB 3838—2002地表水环境质量标准》Ⅲ类水质。     

The anaerobic oxidation of ammonium

From recent research it has become clear that at least two different possibilities for anaerobic ammonium oxidation exist in nature. 'Aerobic' ammonium oxidizers like Nitrosomonas eutropha were observed to reduce nitrite or nitrogen dioxide with hydroxylamine or ammonium as electron donor under anoxic conditions. The maximum rate for anaerobic ammonium oxidation was about 2 nmol NH4+ min-1 (mg protein)-1 using nitrogen dioxide as electron acceptor. This reaction, which may involve NO as an intermediate, is thought to generate energy sufficient for survival under anoxic conditions, but not for growth. A novel obligately anaerobic ammonium oxidation (Anammox) process was recently discovered in a denitrifying pilot plant reactor. From this system, a highly enriched microbial community with one dominating peculiar autotrophic organism was obtained. With nitrite as electron acceptor a maximum specific oxidation rate of 55 nmol NH4+ min-1 (mg protein)-1 was determined. Although this reaction is 25-fold faster than in Nitrosomonas, it allowed growth at a rate of only 0.003 h-1 (doubling time 11 days). 15N labeling studies showed that hydroxylamine and hydrazine were important intermediates in this new process. A novel type of hydroxylamine oxidoreductase containing an unusual P468 cytochrome has been purified from the Anammox culture. Microsensor studies have shown that at the oxic/anoxic interface of many ecosystems nitrite and ammonia occur in the absence of oxygen. In addition, the number of reports on unaccounted high nitrogen losses in wastewater treatment is gradually increasing, indicating that anaerobic ammonium oxidation may be more widespread than previously assumed. The recently developed nitrification systems in which oxidation of nitrite to nitrate is prevented form an ideal partner for the Anammox process. The combination of these partial nitrification and Anammox processes remains a challenge for future application in the removal of ammonium from wastewater with high ammonium concentrations.     

Biostorage Polymers Phenomena in Cheese Wastewater Treatment by a Sequencing Batch Reactor

Typically, microbes associated with biological wastewater treatment processes are subjected to dynamic organic and nutrient loading conditions. This constantly changing environment imposes a stress, referred to as “feast-famine” that selects for microbes capable of biologically storing substrates as polymers during high organic concentration periods (i.e., feast) for use during periods of low organic availability (i.e., famine). In this study, we monitored the production of biostorage polymers generated with actual cheese wastewater treatment by way of sequencing batch reactors (SBRs). SBRs were employed and operated in duplicate under two long (i.e., hours) filling scenarios (1) “react fill” with mixing/aeration and (2) “static fill” with no mixing/aeration. Despite comparable effluent water quality levels, the results reveal that a “static fill” approach outperforms a “react fill” with respect to maximum biostorage polymer production (50% more poly-β-hydroxybutyrate, 15% more glycogen). The presence of biostorage polymer production has been shown to be indicative of a more stable and robust process.