Use of Air Stripping Technology to Remove Ammonia from Biologically Treated Blue Crab Processing Wastewater     

《Journal Of Aquatic Food Product Technology》2013,22(4):81-97

Abstract

Crab cooker wastewater contains high concentrations of chemical oxygen demand (COD), total suspended solids (TSS), and total Kjeldahl nitrogen (TKN). Anaerobic biological treatment of the wastewater releases high concentrations of ammonia. In this study, the potential for air stripping to remove ammonia from wastewater which was treated biologically under anaerobic conditions was evaluated. An air stripping tower's ammonia removal efficiency increased from 50 to 72 percent as the air flowrate was increased from 9 to 21 m³/min. The average liquid loading rate and liquid temperature were 25 L/m²/min and 14^GC, respectively. Ammonia stripping efficiency increased as the stripping factor was increased from one to three; however, under the conditions of this study (2,3 inch LanPac packing and countercurrent tower), stripping factors from two to three were only possible at low liquid loading rates (less than 41 m-Vm²/min) due to pressure drop considerations. At liquid loading rates less than 41 m-Vm²/min, the product of the overall mass transfer coefficient (KL) and the specific interfacial area (a) increased with increasing liquid loading rate, probably because more of the packing surface was wetted at higher liquid loading rates.  相似文献   

Acute and chronic effects of aqueous ammonia on marbled spinefoot rabbitfish,Siganus rivulatus (Forsskål 1775)     

Rana Roumieh  Abir Barakat  Nabila E Abdelmeguid  Joly Ghanawi  Imad Patrick Saoud 《Aquaculture Research》2013,44(11):1777-1790

Ammonia is a metabolite of aquatic organisms which might reach deleterious levels in intensive fish farms. The aim of the present study was to determine median lethal concentrations (96‐h LC₅₀) of total ammonia nitrogen (TA‐N) on marbled spinefoot rabbitfish (Siganus rivulatus) and chronic effects of TA‐N on survival, growth and behaviour of juvenile rabbitfish over a 50 day period. In the first experiment, fish were exposed to 0, 2, 4, 6, 8, 10, 12, 14, 16, 18 and 20 mg L^?1 TA‐N for 96 h and survival evaluated. In the second experiment, 12 fish were stocked per 50‐L tank and treated with one of 0, 2, 4, 6, 8, 10 and 12 mg L^?1 TA‐N with three replicate tanks per treatment. Survival and growth were determined and histopathological alterations of gills due to chronic ammonia exposure were studied by light and electron microscopy. The 96‐h LC₅₀ values were 16–18 mg L^?1 TA‐N. In the chronic exposure experiment, fish reared in water with 0 mg L^?1 TA‐N had 100% survival and had 50% weight increase in 50 days. Fish at 2 and 4 mg L^?1 TA‐N all died whilst fish in 6, 8, 10 and 12 mg L^?1 TA‐N survived and grew albeit less than in treatment 0 mg L^?1. Gills from ammonia treated fish displayed severe histological and ultrastructural alterations including hyperplasia, hypertrophy and fusion of secondary lamellae, aneurysms and presence of pleomorphic altered cells. Chronic exposure to ammonia is deleterious to marbled spinefoot rabbitfish and low concentrations of ammonia appear to kill the fish in <50 days whilst fish can survive for more than 50 days at concentrations between 6 and 12 mg L^?1 TA‐N.  相似文献   

不同摄食水平哲罗幼鱼排氨率的研究   总被引：1，自引：0，他引：1  

杨贵强  张永旺  徐绍刚  贺杰  王建 《中国农学通报》2014,30(35):112-115

为了解摄食水平对哲罗幼鱼排氨率的影响,制定更科学的投喂策略,采用实验生态学方法研究了3个摄食水平(2%、4%、6%)的哲罗(Hucho taimen)幼鱼摄食前后的排氨率。结果显示：摄食后,3个摄食水平的哲罗幼鱼的排氨率均迅速上升,到达最大值后再缓慢下降,最后恢复到各自的初始水平;3个摄食水平的哲罗幼鱼的排氨持续时间(DNR)为(17.0±0.30)、(18.0±0.50)、(19.0±0.60) h,排氨率峰值时间(TNR)为(7.0±0.00)、(7.0±0.20)、(8.0±0.60) h,二者均随着摄食水平的增加而延长;哲罗幼鱼平均排氨率(NRave)和最大排氨率(NRmax)与摄食水平(m)之间的拟合方程分别为：NRave=1.1917+0.1581m(R2=0.9783,2.15%＜m＜6.36%);NRmax=1.2516+0.2595m(R2=0.9706,2.15%＜m＜6.36%)。结果表明：哲罗幼鱼养殖过程中要适当的增加投喂次数和减少每次投喂量;伴随着摄食水平增加,哲罗幼鱼体内多余的氨基酸也会增加,外源性排泄也随之升高。  相似文献   

Impact of Long-Term Fertilization on Community Structure of Ammonia Oxidizing and Denitrifying Bacteria Based on amoA and nirK Genes in a Rice Paddy from Tai Lake Region,China          下载免费PDF全文

JIN Zhen-jiang  ;LI Lian-qing  ;LIU Xiao-yu  ;PAN Gen-xing  ;Qaiser Hussein  ;LIU Yong-zhuo 《农业科学学报》2014,13(10):2286-2298

Ammonia oxidizing （AOB） and denitrifying bacteria （DNB） play an important role in soil nitrogen transformation in natural and agricultural ecosystems. Effects of long-term fertilization on abundance and community composition of AOB and DNB were studied with targeting ammonia monooxygenase （amoA） and nitrite reductase （nirK） genes using polymerase chain reaction- denaturing gradient gel electrophoresis （PCR-DGGE） and real-time PCR, respectively. A field trial with different fertilization treatments in a rice paddy from Tai Lake region, centre East China was used in this study, including no fertilizer application （NF）, balanced chemical fertilizers （CF）, combined organic/inorganic fertilizer of balanced chemical fertilizers plus pig manure （CFM）, and plus rice straw return （CFS）. The abundances and riehnesses of amoA and nirK were increased in CF, CFM and CFS compared to NF. Principle component analysis of DGGE profiles showed significant difference in nirK and amoA genes composition between organic amended （CFS and CFM） and the non-organic amended （CF and NF） plots. Number of amoA copies was significantly positively correlated with normalized soil nutrient richness （NSNR） of soil organic carbon （SOC） and total nitrogen （T-N）, and that of nirK copies was with NSNR of SOC, T-N plus total phosphorus. Moreover, nitrification potential showed a positive correlation with SOC content, while a significantly lower denitrification potential was found under CFM compared to under CFS. Therefore, SOC accumulation accompanied with soil nutrient richness under long-term balanced and organic/inorganic combined fertilization promoted abundance and diversity of AOB and DNB in the rice paddy.  相似文献   

氨排放清单编制的初步研究   总被引：2，自引：0，他引：2  

王阿婧  张双  瞿艳芝  苏日嘎其其格  朱晓  刘桐坤 《湖北农业科学》2016,(2):345-348

介绍了欧洲和美国氨排放清单研究历程、编制方法和氨排放源构成,以及中国氨排放清单研究现状,汇总并分析了氨排放清单编制方法,提出了中国进一步完善氨排放清单的建议。  相似文献   

凡纳滨对虾高氨氮和低溶氧抗逆性状的杂交配合力分析     

胡志国  刘建勇  袁瑞鹏  张嘉晨 《南方水产科学》2016,(1):43-49

该研究利用3个凡纳滨对虾(Litopenaeus vannamei)引进群体,采用完全双列杂交交配设计,建立9个自繁和杂交组合F1代,比较幼虾对高氨氮和低溶解氧的耐受性,分析各交配组合杂种优势,采用线性模型均数加权二乘分析法估算凡纳滨对虾高氨氮和低溶氧抗逆性状的配合力,评估亲本及子代的耐受性能。结果表明,9个群体对氨氮(NH3-N)和溶解氧(DO)胁迫的耐受性均存在显著差异,杂交子代耐高氨氮和耐低溶氧性状的中亲优势和超亲优势范围分别为14.09~42.57和1.860~26.18、-52.48~31.39和-54.34~24.66;杂交后代耐受性的表现受到父本、母本一般配合力以及杂交组合特殊配合力共同影响,美国夏威夷SIS群体(UH)耐高氨氮和低溶氧性状的一般配合力较高,分别为0.144 2和0.089 9;特殊配合力分析表明,美国迈阿密SIS群体(UM)和美国夏威夷SIS群体的杂交组合(UM×UH)为强优势组合,存在较强的抗逆非加性效应,杂交优势明显,可为进一步家系选育提供候选材料。  相似文献   

应用反演式气体扩散模型测定奶牛养殖场氨排放特征研究     

杨园园  王雪君  刘春敬  廖文华  高志岭  谢芹  马文奇 《河北农业大学学报》2016,(4):25-30

本研究采用反演式气体扩散技术与开路激光测定装置相结合的研究方法,测定了集约化奶牛养殖场(产奶量接近我国平均水平)的季节氨排放,旨在研究奶牛养殖过程中氨排放的日排放特征、季节排放特征及排放强度。结果表明:奶牛养殖场氨的日排放规律表现出中午高、夜间低的特征,该特征是由风速和温度的复合影响所致。不同季节的氨气日排放速率范围为119.5~191.0g/(head·d)(变异系数为19%),其中以冬季最低,夏季和春季最高,因此温度的季节性差异是主要原因。各季节氨气排放速率平均为160.9g/(head·d),相应的年排放因子为58.7kg/(head·年),其氨氮(NH3-N)损失占饲料氮素的34.5%,排放强度(生产1t标准牛乳的氨气排放量)为17.1kg。在未来还应加强开放型奶牛场N循环对饲料氮素的损失系数及其排放强度的影响的研究。  相似文献   

氨氮和亚硝酸氮对偏顶蛤的急性毒性研究     

张晓森  宁军号  常亚青  李磊  李开全 《安徽农业科学》2016,(8):115-117

[目的]研究氨氮和亚硝酸氮对偏顶蛤的急性毒性,为合理调控偏顶蛤水体中氨氮与亚硝酸氮提供参考价值。[方法]采用常规生物毒性试验方法,研究偏顶蛤对氨氮和亚硝酸氮毒性的耐受力。[结果]氨氮对偏顶蛤的半致死浓度96 h LC50为158.85 mg/L,安全浓度(SC)为15.89 mg/L;非离子氨对偏顶蛤半致死浓度96 h LC50为14.06 mg/L,安全浓度(SC)为1.41 mg/L。亚硝酸氮对试验蛤的半致死浓度96 h LC50为54.20 mg/L,安全浓度(SC)为5.42 mg/L。[结论]与亚硝酸盐相比,偏顶蛤对总氨氮毒性的耐受力更强,非离子氨对偏顶蛤的毒性最强。  相似文献   

移动床生物膜反应器处理低浓度氨氮养殖废水试验     

李月  张宇雷  吴凡  刘晃  管崇武  宋红桥  单建军 《渔业现代化》2014,41(4)

采用移动床生物膜反应器(MBBR)处理低浓度氨氮养殖废水,在不同水力停留时间(HRT)和不同曝气条件下,分析MBBR处理人工模拟的低浓度氨氮(2 mg/L左右)养殖废水的进出水氨氮、亚硝酸盐氮和硝酸盐氮的浓度变化,探讨HRT和曝气量对MBBR处理低浓度氨氮养殖废水的影响,并以实际鲟鱼养殖废水(氨氮浓度0.5～1.5 mg/L)和其他研究成果进行验证和比较.结果显示:MBBR的最优HRT为6～8 min,最优曝气量为180 L/h,相应的氨氮去除率为70％ ～ 75％,氨氮去除负荷为560～700 g/(m3.d),填料生物膜厚度为26～38 μm;膜表层结构多样,物种丰富,膜生长良好.该反应器对处理低浓度氨氮养殖废水具有的高效能力.  相似文献   

微电流电解去除养殖海水中氨氮效果     

叶章颖  裴洛伟  林孝昶  顾招兵  王朔  朱松明  阮贇杰 《农业工程学报》2016,32(1):212-217

为了探究微电流电解技术去除养殖水体中氨氮的效果,试验以盐度为30‰(质量分数)人造海水为对象,设置了循环水温度、流速和电流密度3个参数以及对应参数的3个水平,探究其对氨氮去除率的影响。试验结果表明,在试验设置的温度(18、25、32℃)和流速(100、300、500 m L/min)条件下,循环水温度和流速的变化对氨氮去除率影响并不明显。试验设置的电流密度(20、40、60 A/m2)条件下,对氨氮去除率有明显作用,且电流密度越大,单位时间内氨氮去除速率越快。正交试验确定了最优去除条件为电流密度、水温和流速分别为40 A/m2、32℃、500 m L/min。通过能耗分析可知,在设定的参数范围内,不同温度条件下最低能耗条件为电流密度40 A/m2、流速300 m L/min,最低的能耗为21.26 Wh/kg。研究结果可以为微电流电解在海水循环水养殖中氨氮降解提供参考。  相似文献