| Industrialized mariculture is an important approach to increasing productivity. It is also an effective measure for mankind to realizing controllable and high effective mariculture and resolving the crisis of increasingly exhausted ocean resource by high technology.The deterioration of water quality caused by high density of mariculture in industrialized mariculture system and bait casting is one of key factors that the system can be kept to normally produce. It is a key technique for normal work of industrialized mariculture system and ensuring of stable and effective production that study and establishment high effective water purified system and its application in circle water treatment of industrialized mariculture. So study and establishment high effective water purified system and its applications in circle water treatment of industrialized mariculture have important academic meaning and will have wide application.In this paper, the effective purified technique and method for the circle water system of mariculture for young seashell were studied based on the water property. The circle water system of mariculture for young seashell was purified by foam fractionation- ozone disinfection- activated carbon adsorption coupled treatment technique. The removal rate of organic compounds and influence factors with foam fractionation- ozone disinfection- activated carbon adsorption method were systemically studied. The technique parameters were optimized. The satisfactory results were obtained. The circular use of industrialized mariculture water was realized. The following is the major results in this paper: 1. It is practicable to remove organic compounds in circle water of mariculture by foam separators. The removal rate of foam separator was affected by some factors, such as, the concentration of organic compounds and optimal vapor/liquid proportion. The concentration and quality of organic compounds were the key factors of effecting removal rate of foam separator. The removal results of organic compounds by foam separator were satisfactory under the condition of optimal vapor/liquid proportion, minimum velocity of surface vapor and optimal retention time.2. The main water quality parameters of seawater after ozone disinfection, including pH, oxidation -reduction potential (ORP), chemical oxygen demand (COD), dissolved oxygen (DO), ammonia (NH4-N), nitrite(NO2-N), total bacteria count, can achieve the demand of the aquaculture water quality. The water quality was distinctly modified after ozone disinfection.3. The biology culture experiment shows that ozone produced oxidant (OPO) can heavily affect the growth of Chlorella sp. cultured by seawater after ozone treatment. When the concentration of OPO was under the level of 0.735mg/l, the ozone produced oxidant was harmless to the growth of Chlorella sp.; while it is obviously harmful when above 1.036mg/l, a lot of chlorella sp. had perished. The quantitative relation between dosage of ozone and growth of Chlorella sp. was obtained. The means to eliminating and controlling the harmful effect of ozone was proposed.4. The activated carbon can effectively adsorb ozone and make the ozone transform to oxidant. The concentration of residual ozone-produced-oxidants in the water after activated carbon adsorption was less to 0.1 mg/l, under the condition that the imput water flow-rate was 45.6 l/h and the height of carbon bed was higher than 800mm, which was the optimal height of activated carbon adsorption column, the imput water quality was kept constant. Under the above condition, the re-circle water after ozone treatment can be sterilized, and the harmful effect produced during the ozone disinfection was avoided.5. The experimental results show that there is a quantitative relation between TRO and ORP. Therefore, a simple and reliable mehtod to monitor the ORP was obtained, by determination of ORP tracing the TRO concentration in the water after treatment. The method gives guiding role and applied value in the practical production.6.This experiment contrasts three different substrates. The granular ceramics media BAF is the best on COD removal,and the bamboo media BAF is the worst ;In the first term of this experiment the granular ceramics media BAF and the suspended media BAF is same on NH3-N removal,and the water quality can achieve the standard of mariculture effluent,but in the last term the granular ceramics media BAF is better than the suspended media BAF on NH3-N removal; The bamboo media BAF has a good effect on the removal of NH3-N and NO2-N. Because of the high price and normal removal on NH3-N and COD, we throw the suspended media. In this experiment, the COD and NH3-N concentrations of the effluent increase with the COD and NH3-N charge increasing. The optimum HRT,media hight and air:liquid in three different media BAF is 1h,60cm and 3:1 respectively.The innovations of the study are the following:1. The pilot study on application of Protein Foam Fractionation and Ozone Disinfection Technology in circle water system of mariculture for young seashell was carried. Some parameters of protein foam separator for certain quality of water were obtained. The harmful effect of ozone produced oxidant on mariculture recirculating water quality was first found, and the approach to eliminating the harmful effect was fist studied. The technique parameters of the circle water treatment of mariculture for young seashell by foam fractionation-ozone disinfection-activated carbon adsorption coupled treatment technique were obtained. 2. The influence of ozone and its oxidants in seawater on the growth of Marine Microalgae was discussed, based on study on improvement of recirculating mariculture water quilaty by the treatment of ozone.3. A simple method to determination of harmful components was proposed, and it can give guiding role and applied value in the practical production.4.This experiment studies the Start—up of different medias BAF in the seawater, the possible thing effecting Start—up,and the effect of NH3-N charg,COD charg,HRT,media hight,water temperature,pH and gas:liquid on the removal of NH3-N and COD.
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