| Modern fishery development, in the process of seawater aquaculture model with less land, water saving, energy saving, emission reduction, and the breeding process is not affected by the external environment, much attention has been paid to the advantages of so this way is the important direction of the aquaculture development in the future.This paper introduced several important links about the circulating water aquaculture, such as the adjustment of the pH value increases oxygen, pure oxygen and ozone disinfection and foam drainage are studied, at the same time use the results of the study on the corresponding equipment and circulating water aquaculture process is optimized and integrated.Finally using the optimization of circulating water aquaculture system conducted one-year pearl gentian grouper aquaculture research. The results areas follows:1) This article innovation developed a set of circulating water aquaculture pH automatic adjusting device.Through the experimental result, the set of device can automatically adjust the circulating water aquaculture ponds stable at pH 6.5 ~ 8 a narrow range, so that we can base on the needs of different breeding objects of pH, set the corresponding pH adjustment range, and make its stability, achieve the goal of farmed animals in security and the environment.In this paper, for the regulation of pH in the circulating water aquaculture provides a new method and theoretical basis.2) the experiment was improved on adding oxygen equipment, the results showed that:When the oxygen of 5 L/min using atmospheric oxygen cone venturi way of oxygen supply outlet dissolved oxygen can reach 16.37 mg/L, the added value of dissolved oxygen(do) reached 8.94 mg/L, increasing oxygen rate was 120.32%, the oxygen utilization rate was 62.56%; Atmospheric oxygen cone perforated stone way of oxygen supply outlet dissolved oxygen can reach 15.56 mg/L, the added value of dissolved oxygen(do) reached 7.88 mg/L, increasing oxygen rate was 102.60%, the oxygen utilization rate was 55.14%, and the use of the method in the oxygen supply for 4 L/min when the maximum oxygen utilization rate reached to 57.29%;Cone pressurized oxygen, oxygen to venturi outlet dissolved oxygen can reach 16.79 mg/L, the added value of dissolved oxygen(do) reached 9.34 mg/L, increasing oxygen rate was 102.60%, the oxygen utilization rate was 65.36%; Oxygen pressure cone, perforated stone way of oxygen supply outlet dissolved oxygen can be up to 16.43 mg/L, the added value of dissolved oxygen(do) reached 8.87 mg/L, increasing oxygen rate was 117.33%, the oxygen utilization rate arrived 50.07%.In conclusion,it can be drawn that using venturi gas to the mode of oxygen for increasing oxygen cone effect is better than the use of perforated stone raise the cone effect of increasing oxygen for gas, oxygen pressure Increased oxygen cone effect is better than normal pressure cone for increasing oxygen effect.3)This study also used new Broadway homemade ozone machine production of ozone and the aquaculture water for processing. The results as follows:When ozone concentration was low to nitrite removal rate as high as 95.7%, and the COD removal rate was 19.77%, but in a short period of time without of ammonia nitrogen removal ability also made ammonia nitrogen concentration increased.Only when the ozone concentration was high enough for ammonia nitrogen removal efficiency, but high concentration ozone against farmed animals, so we could think ozone in the closed loop system of aquaculture water ammonia nitrogen removal was invalid.4) Experiments also used two kinds of gas to the mode of foam separator TSS and COD removal in the process of aquaculture water body, the results showed that:Venturi foam separator of TSS removal rate was as high as 30.81%, and the scattered gas bubble separator of TSS removal rate was as high as 25.81%.Venturi foam separator on COD removal efficiency reached 25.82%, and the scattered gas bubble separator on the COD removal rate arrive to 22.38%.5) In the closed circulating water aquaculture system optimization was carried out after one-year pearl gentian grouper aquaculture experiment, the results showed that:Water temperature is between 26 and 29 during breeding, salinity℃ reached 25~30, dissolved oxygen(DO) was 8 mg/L,the ammonia nitrogen concentration was 0.3 ~ 0.9 mg/L, nitrite was 0.1 ~ 0.25 mg/L, and the pH was above 6.0. During breeding,the SGR was 0.64 + /- 0.03 on average, the total survival rate was 80.11%, the average feed coefficient was 1.03,the density increased from 13.82 kg/m3 to 13.82 kg/m3, and the input-output ratio was 1:2. 61, the results will be used as a basis for high density cultured pearls gentian grouper... |
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