Test And Evaluation Among Rotary Impeller And Microrous Pipe Aeration Aerator

China is the earliest country engaged in aquaculture in the world,the history can be traced back to the 12th century BC.Pond-culture industry has entered into a rapid development stage since the founding of PRC.In 2012,the national aquaculture area was 8.0884 million hectares and the total output was 42.8836 million tons.Among of them,the fresh water pond aquaculture area was 5.9075 million hectares.Pond farming has become the main cultivation mode in China.The crab and shrimp farming are favored by more and more farmers in recent years,as they can bring more economic efficiency.Rotary impeller aerator is good at increasing the oxygen content of the upper water in the pond,but it's not so good for the farther and lower water,and at the same time,it's not efficiency in water exchanging adequately,oxygen increasing uniformly,and the quality improving of water.Micro-porous pipe aeration aerator not only has better effect on increasing the oxygen content,but also it can take away the harmful material at the bottom of the pond.But because of the economic factors and so on,it's hard for farmers to accept the new equipment and technology.In this paper,the contrast test and analysis will be carried out between the rotary impeller aerator now used mainly and micro-porous pipe aeration aerator extended widely.At the clear water pond and the crab or fish breeding pond,the ability of increasing the oxygen,the power efficiency and the effect to the pond water parameters during the breeding process are tested and contrasted under the different increasing oxygen ways,otherwise the economic benefit of the micro-porous pipe aeration aerator is analyzed by investigating and researching,all of the above can provide certain reference for the farmers who breed the shrimp and crab to select the way to increase the oxygen content of the pond water.The result shows that,under the condition of the clear water pond in the lab,the increasing oxygen average ability of the rotary impeller aerator which power is 1.5 kW is 2.32 kg/h,it is worse than the increasing oxygen average ability of the same power micro-porous pipe aeration aerator which is 2.65 kg/h,on the other hand,when the micro-porous pipe length range of the micro-porous pipe aeration aerator which power is 1.5kWis between 20m and 200m,more length,more speed of increasing the oxygen.Under the condition of the crab or fish breeding pond,after working for 120 minutes,the oxygen content of the water below the surface 100cm becomes to 4.27mg/L in the pond installed the micro-porous pipe aeration aerator,it is more than 3.05 mg/L which is become to in the pond installed the rotary impeller aerator.Both of the rotary impeller aerator and the micro-porous pipe aeration aerator are effective to cool the water after working,but the micro-porous pipe aeration aerator is more effective and it can reduce the water temperature all of the level in the pond.On the aspect of water quality,the fi values of pond used rotary impeller aerator are more than 1 depending on Nemerow index,it is within the scope of the light pollution,but the fi values of pond used micro-porous pipe aeration aerator are less than 1,it is within the light clean scope;In terms of economic efficiency,the benefit that the micro-porous pipe aeration aerator brings is obvious.In the case of breeding the shrimp and crab,the input-output ratio which is used micro-porous pipe aeration aerator is 0.30,it is less than 0.48 which is the input-output ratio that used the rotary impeller aerator.