池塘养殖中不同机械增氧技术的组合及效果验证

为解决河南中牟县万滩镇养殖池塘机械增氧技术单一的问题,通过试验研究微孔式、水车式、涌浪式等几种增氧机的性能及使用方式,以达到提升增氧效果和提高养殖效益的目的。结果表明,该地区池塘溶氧含量高而利用率低,养殖户传统增氧方法不当。适宜增氧方式为:涌浪式增氧机适合在晴天下午使用3~6 h,可有效提升周边20 m范围内底层水体的溶氧水平;投食前后半小时开启和关闭微孔式、水车式增氧机,可提升投食期间投饵区溶氧水平1~2 mg/L,保证鱼群的进食效果;夜间搭配使用微孔式和低功率叶轮式增氧机增氧,可使微孔区域底层水体溶氧比不增氧状态高出1 mg/L以上。     

射流式增氧机性能研究

为评价射流式增氧机性能,采用SC/T 6009-1999<增氧机增氧能力试验方法>标准,通过清水试验和养殖池塘试验,研究了射流式增氧机在清水中的增氧能力、动力效率,以及实际养殖池塘中上下水层溶解氧变化.结果表明:射流式增氧机对于下层水体具有良好的增氧效果,能使1.5 m水深处溶氧值提高31.0%;利用产生的水流搅拌水体...     

典型增氧设备在养殖池塘中组合应用的研究

叶轮式、水车式、射流式和曝气式增氧机是目前我国池塘养殖使用的主要增氧设备;由于结构形式和工作原理的不同,4种形式的增氧机有不同的特点和功能。为提高养殖池塘增氧设备的增氧效果,通过增氧设备对养殖池塘水体不同深度增氧效果的试验和养殖池塘自然增氧的试验,分析了4种典型的增氧设备的增氧性能和特点,提出了叶轮式增氧机与耕水机、水车式增氧机与耕水机、水车式增氧机与射流式增氧机以及曝气增氧机与耕水机组合配置使用的混合增氧模式,可以优势互补,充分发挥各种形式增氧设备功能。通过组合使用,达到对养殖池塘水体最大限度的增氧效果的目的。     

涌浪式增氧机性能研究

为研究涌浪式增氧机的性能,对13台样机按照标准规定的方法进行增氧性能试验,并对结果数据进行统计分析,同时在养殖池塘中进行提水性能和造浪性能的试验。结果显示:涌浪式增氧机的绝对增氧能力与同功率水车增氧机相近,在标准水池试验的平均增氧能力Q_S和动力效率E_S达到SC/T6017—1999《水车式增氧机》标准的要求;1.5 kW涌浪式增氧机的提水性能可以达到3 006.05 m~3/h,提水动力效率为1 869.4 m~3/kW·h,理论上,一台1.5 kW的涌浪式增氧机运行1 h可以完成一个100 m×50 m标准养殖池塘底层水体和上层水体的交换;涌浪式增氧机可以在距离固定位置30 m的水面形成波幅为80 mm的波浪。研究表明:在实际使用中,涌浪式增氧机的增氧效率优于水车式增氧机;在相同面积的养殖池塘中,使用相同功率涌浪式增氧机的数量比叶轮式增氧机的要少。     

增氧机池塘增氧效果试验的研究

研究不同型式的增氧机性能,可使生产者根据不同养殖对象与模式针对溶氧的需求,选择配置合适的增氧方式。通过对使用最为广泛的叶轮式、水车式、射流式和曝气式增氧机产品性能的池塘实效试验,分析比较各类增氧机性能、工作特性和适用范围。结果表明,养殖水体溶解氧主要来自浮游植物的光合作用;叶轮式、水车式和射流式增氧机应用于服务水域,其增氧能力远远不能满足该水域养殖鱼类的氧需求,但可满足养殖鱼类的应急氧需求;曝气式增氧机因没有应急增氧作用和水体搅拌能力而不适合四大家鱼等常规鱼种的养殖需要。     

技术推广微孔曝气增氧技术

水产养殖常用的增氧设备主要有叶轮式增氧机、水车式增氧机、流射式增氧机、喷水式增氧机和曝气增式氧机等。叶轮式或水车式增氧机主要是设置在水体上层,单独使用很难满足养殖池塘的立体增氧要求,而且能耗相对较高。曝气增氧又可细分为气石曝气增氧和微孔管曝气增氧两种,其区别在于气体的扩散器,     

池塘底充式增氧设施的配置与应用

为研究高效增氧方法,选择在凡纳滨对虾(Penaeus vannamei)和三疣梭子蟹(Portunus trituberculatus)生产性养殖池塘,进行底充式增氧设施的配置与应用研究.结果表明,底充式增氧方法比水车式和叶轮式增氧机的增氧效果明显.实际应用中微孔管和PVC管作为充气管,两者增氧效果基本相同,PVC管道更经济实用;充气管道的合理间距为4～6 m,鼓风机的功率配置0.30 kW/667 m2,可以满足水体溶解氧最低值3 mg/L的增氧要求.     

压力式氧溶解装置在凡纳滨对虾养殖方面的应用

研究设试验组和对照组,试验组使用压力式氧溶解装置进行池塘增氧和自动化在线溶氧监测,对照组为常规充气式增氧机。试验证实,试验组能够保证养殖期间凡纳滨对虾对水体溶氧水平(4mg/L)的需求,而对照组则不能完全满足对虾养殖对溶氧的要求。试验组虾的生长情况要明显好于对照组;试验组池塘的水色始终保持茶褐色,而对照组为绿色,并伴有微囊藻水华。     

池塘养殖鲟鳇鱼应注意的几个问题

鲟鳇鱼属大型鱼类,其生长速度快,抗病力和适应力强,池塘养殖鲟鳇鱼时应注意以下几个问题: 1.池塘条件 池塘面积以5～10亩为宜,水深2～ 3m,水质较稳定,水体溶氧量在5mg/L以上.池底平坦,无渗漏,淤泥层小于5cm,有条件可在池底铺一层1～2cm粒径的河沙.配备一台水车式增氧机,并设置饲料台.     

移动式水库增氧机初探

浅水鱼池中，目前采用固定式水车增氧机增氧。增氧时，机器往往被固定在鱼池中央，由于水车增氧机搅水能力不强，水体产生循环水流的强度不高，周围水体的溶氧受到一定限制，整个鱼池溶氧均匀性较差。采取将水车增氧机在池中作水平移动增氧，可收到良好效果。     

叶轮式增氧机性能研究

叶轮式增氧机具有增氧、搅拌和曝气等功能.通过对其近10年1.5 kW、3.0 kW两种型号的增氧能力和动力效率这两个主要性能指标每年的检测平均值进行统计,以及实际养殖池塘试验中上下水层溶解氧、水温变化的研究;结果表明,运转80 min左右,可使距增氧机10 m、1.5m深处底层水体的溶解氧和水温与上层水体一致,从7.3...     

Author index

Oxygen-transfer rates (tap water, 0 mg/l dissolved oxygen, 20°C) for four tractorpowered emergency aerators tested in a 820-m³ pond were: blower-fan aerator, 12.2 kg O₂/h; Crisafulli^® pump and sprayer, 12.3 kg O₂/h; Airmaster^® aerator (centrifugal pump and sprayer), 21.3 kg O₂/h; paddlewheel aerator, 26.3 kg O₂/h. Times required for aerators to homogeneously mix salt in a 6000-m³ pond were: blower-fan aerator, 96 min; Crisafulli pump and sprayer, 94 min; paddlewheel aerator, 53 min; and Airmaster aerator, 38 min. The Airmaster aerator and the paddlewheel aerator did not differ in their abilities to transfer oxygen and circulate pond water (P > 0.05); they were both superior to the blower-fan aerator and the Crisafulli pump and sprayer (P < 0.01).     

Vertical Water Circulation Capabilities of an Electric Paddle Wheel Aerator and Dissolved Oxygen Loss Due to Daytime Aeration

ABSTRACT

Vertical water circulation by the paddle wheel aerator was determined by measuring dissolved oxygen profiles in a 3.6-m deep watershed pond during daylight hours, using aerated and non-aerated treatments. The paddle wheel aerator circulated the well-oxygenated surface water to the pond bottom, producing a uniform dissolved oxygen profile in the aerated treatment, while the non-aerated treatment maintained high dissolved oxygen concentrations near the surface with low dissolved oxygen concentrations near the pond bottom. The aerated treatment contained 35.6% less dissolved oxygen than the non-aerated treatment after four hours as a result of operating the aerator during the daytime. The paddle wheel aerator, with a shallow (10 cm) paddle immersion, is effective in vertically circulating water in deeper ponds. However, substantial loss of dissolved oxygen may result from operating the aerator on days with high rates of photosynthesis.     

叶轮式增氧机对鱼池溶氧日变化影响的模拟模型初步研究

针对鲜有鱼池溶氧模型考虑增氧机对鱼池溶氧日变化影响的现实,在传统的描述鱼池水温和溶氧日变化多层模型的基础上,通过分析叶轮式增氧机水跃和液面更新对鱼池多层水体中各能量要素和溶氧变化因子的影响,构建了能反映叶轮式增氧机增氧效果的鱼池水温和溶氧日变化模拟模型.通过实验数据对模型的校参和验证,发现溶氧逐小时模拟值与观测数据的均...     

养殖池塘增氧机制与装备性能比较研究

水产养殖过程中,池塘生态系统可分为自成熟期和人工维持期。在养殖容量提高的情况下,养殖生物呼吸需氧量在不断增加,缺氧条件下有机物分解成有害物质,影响养殖生产。维持池塘生态系统稳定的主要工程机制为:通过上下水层交换、平衡营养元素等方法,强化光合作用,提高营养物质转化规模,提升初级生产力;形成生态增氧为主、机械增氧为辅的高效增氧机制。以中国养殖池塘生态系统为研究对象,分析探讨养殖池塘生态机制、水体溶氧理论、增氧机作用机理、不同类型增氧机的机械性能等,提出了大宗淡水鱼混养池塘及几种典型单养池塘增氧机配置方式,从而为池塘养殖系统增氧机的配置提供技术参考。     

Engineering considerations for water circulation in crawfish ponds with paddlewheel aerators

Engineering considerations for paddlewheel aeration in vegetated shallow water ponds for the production of procambarid crawfish is necessary to ensure cost-effective application. Three experimental ponds (approximately 2 ha each) were planted with rice in August as forage for the resident pond population of red swamp crawfish, Procambarus clarkii, and flooded in October. Two 2.2 kW (3 hp), single-phase electric motor (110 V_ac) paddlewheel aerators were placed in each pond. The aerator rotors were 160-cm long and 95-cm in diameter. The aerator rotor had 36 paddles with half the paddles 27.3-cm long and half 34.9-cm long. Rotor speed was set at 83 rpm and operated at three paddle submergence settings: 7.6, 12.7, and 17.8 cm below the water surface. Over a 20-week period between November and April, channel velocity, head difference, and aerator amperage was measured for both one and two aerators in operation in each pond. Results indicated that circulation of oxygenated water from the aerators can be accomplished as efficiently with a single aerator set at a lower paddle depth (7.6-cm) compared to operating two aerators set at a greater paddle depth (12.7 or 17.8-cm). However, based on the apparent efficiency of the aerators and the calculated channel roughness coefficients values obtained from the channel velocities, paddlewheel aerators are an inefficient option for circulating the pond water especially when rice foliage dominants the total vegetative biomass of the pond.     

Design Characteristics of Spiral Aerator

In this study, the performance of a spiral aerator, a modified design of the paddlewheel aerator, was evaluated to determine its applicability in aquaculture ponds. The aeration characteristics of the spiral aerator were determined by conducting aeration experiments in a cement concrete tank of dimension 5 × 5 × 1.5 m. Nondimensional numbers related to oxygen transfer (E) and power consumption (Ne) were proposed and expressed as functions of geometric (number of handles per shaft, n) and dynamic (Froude and Reynolds number) parameters. Simulation equations for oxygen transfer and power consumption based on the Froude criterion were developed. The maximum brake power standard aeration efficiency was achieved at n = 13. Finally, an economic analysis was performed assuming a typical Indian major carp culture pond to determine the optimum rotational speed of the aerator at different pond volumes and dissolved oxygen concentration present in the pond at which the aeration cost is minimized. The results showed that the least aeration cost is achievable when rotational speed of the spiral aerator is only 70 rpm for pond volumes up to 700 m³ and from 120 to 220 rpm for pond volumes exceeding 700 m³.     

An evaluation of three paddlewheel aerators used for emergency aeration of channel catfish ponds

Oxygen transfer rate, power requirement and fuel consumption were determined for three paddlewheel aerators used for emergency aeration of channel catfish ponds. The power requirement of the tractor-powered units was directly related to the diameter of the paddlewheel drum and the paddle immersion depth. Oxygen transfer rates ranged from 6·9 to 41 kg h^?1 and increased linearly with the power requirement. The largest paddlewheel aerator, operated at the maximum paddle depth, produced the highest oxygen transfer rate (41 kg h^?1). Oxygen transfer efficiencies ranged from 1·29 to 1·97 kg kWh^?1.