Preparation Of Ultra-fine Product Of Tourmaline And Its Improvement Effect And Mechanism For Aquaculture Water Quality

With the rapid development of aquaculture industry, the water quality in some areas has beendeteriorated; it has led to the pollution of water quality and great loss of aquaculture directly or indirectlyand made the aquatic product quality reduce, affecting the sustainable development of aquaculture industry.If we don’t treat aquaculture wastewater effectively, it may threaten the health of human beings.Tourmaline has good piezoelectric properties, spontaneous permanent polarity and releasing far infraredradiation which can spontaneously adjust aquaculture redox potentials and pH values, reduce watermolecules cluster, activate water, and still can remove the heavy metal and ammonia nitrogen selectively inthe water and so on. It has very good mechanical chemical stability and can well be reused, not causingpollution to the environment; it is very good functional green environmental protection aquaculture waterpurification materials. Therefore, the paper studied the optimum technological conditions of preparation ofultra-fine powder of tourmaline （UPT）, and also did the research of tourmaline which can activate water,improve pH value, adsorb heavy metal and remove nitrogen and phosphorus and so on. On this basis, itadopted piercing-solidifying method for getting the functional tourmaline balls（FTB）, broading the range oftourmaline application in water treatment and having made up for water treatment insufficiency of thepowder state tourmaline. The main research contents in the paper are as follows:（1） The influence of the different preparation factors studied to ultra-fine powder of tourmalineparticle size: by using the method of mechanochemistry for preparing ultra-fine powder of tourmaline,Nano Particle Analyzer and Potentiometric Analyzer, this experiment analyzed dispersant and dosage, solidconcentration and milling time to the effect of powder products of tourmaline particle size. At normaltemperature and pressure, the experiment adopted horizontal circulation sanding machines to milltourmaline powder of22μm size for6h in Inner Mongolia Chifeng area under the condition of polyphosphate dispersant whose solid dosage and concentration were5%and45%and got ultra-fine powder oftourmaline of average particle size0.17μm which the size distribution was uniform and particle dispersionwas better.（2） Exploring the influence of ultra-fine powder of tourmaline to water molecules cluster: using themethod of nuclear magnetic resonance to measure deionized water and¹⁷O NMR full width at halfmaximum intensity （FWHM）, FWHM is to represent water molecules cluster structure. Through the directeffect between tourmaline and water, the experiment studied the effects of tourmaline dosage, theprocessing time, tourmaline particle size, and the temperature on¹⁷O NMR FWHM of deionized water. Theresults showed that, the ultra-fine powder of tourmaline reduced¹⁷O NMR full width at half maximumintensity for deionized water and the volume of water molecules clusters, and increased the degree of wateractivity. The smaller particle size of tourmaline and the narrower¹⁷O NMR FWHM of deionized water kepta good activity after placing120h, illustrating the tourmaline has the vital role in the activation water area.（3） Studying the regulating and controlling function of ultra-fine powder of tourmaline to water pHvalue: according to the tourmaline’s experiments of regulating and controlling water pH value, it mainlystudied how the ultra-fine powder of tourmaline influenced deionized water, acid and alkali solution andthe pH value of seawater under different conditions. And the results showed that tourmaline within10mincould make deionized water pH value rise to8.91from6.86and adjust the pH values to become neutral orweak alkaline. The salinity of seawater mainly influenced regulation rate of the pH values of seawater bytourmaline, but the final pH values had not been influenced; The more dosage and smaller particle size oftourmaline can change the pH value of the sea more greatly. The effect of tourmaline to acidic solution pHvalue was greater than that of the pH value in the alkaline solution, which is the tourmaline surfacehydroxyl electrical functions. After recycling four times, the effect of tourmaline’s regulating andcontrolling pH value of the seawater was good, showing that the process is simple, the effect is good, andhas no pollution.（4） The adsorption effect of ultra-fine powder of tourmaline to heavy metal ions in the solution: usingatomic absorption spectrophotometer, the experiment studied how the single heavy metal ions oftourmaline was influenced by some factors such as the adsorption time, tourmaline dosage, initial solutionpH value, initial ion concentration and adsorption temperature and so on, and did the same research to themixed heavy metal ions adsorption. The result showed: Cu²⁺、Pb²⁺and Zn²⁺in the solution of ultra-finepowder of tourmaline had significant adsorption effect.The best technical parameters of tourmaline toheavy metal ions adsorption was: adsorption time for30min, dosage for5g/L, initial pH value for6.0⁷.5, the initial concentration of the solution for57.2mg/L, adsorption rate of the solution to Cu²⁺for99.93%, adsorption capacity for11.43mg/g, adsorption time for30min, tourmaline dosage for5g/L, initial pH value of solution for4.0⁶.5, the initial concentration of the solution for103.6mg/L, adsorptionrate of tourmaline to Pb²⁺for99.99%, adsorption capacity for20.57mg/g, adsorption time for30min,tourmaline dosage for5g/L, solution initial pH value for6.0⁷.5, the initial concentration of the solutionfor43.6mg/L, adsorption rate of tourmaline to Zn²⁺for98.26%, and adsorption capacity for8.57mg/g.The ultra-fine powder of tourmaline adsorption was conforming to the Langmuir isothermal adsorptionequation. The maximum adsorption to heavy metal ions, Cu²⁺、Pb²⁺and Zn²⁺by the ultra-fine powder oftourmaline was18.59,133.33and15.41mg/g, respectively. The competitive adsorption by UPT to thethree ions was observed in blended solution with Cu²⁺、Pb²⁺and Zn²⁺, and the adsorption capacity of UPTfor multi-metal ions system decreased in an order of Pb²⁺、Cu²⁺and Zn²⁺.（5） Exploring the adsorption characteristic of ultra-fine powder of tourmaline to N, P throughchanging the different affecting factors: by changing the different affecting factors to explore the adsorptioncharacteristic of ultra-fine powder of tourmaline to N, P （phosphate, ammonia nitrogen and nitrite） in theaquaculture water, the results was that the tourmaline had good adsorption performance to PO₄^3--P、NO₂^--Nand NH₄⁺-N in the solution.The best adsorption conditions of tourmaline to PO₄^3--P was: dosage for5g/L,adsorption time for80min, initial pH value solution for2.0, solution concentration for50mg/L, theadsorption rate of P-O3-4-P in the solution by tourmaline is66.74%; the optimum parameters of tourmalineadsorption to NO2-N is5g/L, adsorption time was60min, initial pH value was2.0, the initialconcentration of the solution was50mg/L, this time tourmaline adsorption rate in the solution to NO₂^--Nwas78.40%; the best parameters of tourmaline adsorption to NH₄⁺-N was5g/L, adsorption time was80min, initial pH value solution was1+0.0¹2.0, the initial concentration of the solution was50mg/L,tourmaline adsorption rate to NH4-N was63.70%. The tourmaline adsorption model and Langmuirisothermal adsorption equation was consistent, the biggest adsorption capacity of tourmaline to PO₄^3--P、NO₂^--N and NH₄⁺-N were14.71,11.90and6.76mg/g, and also its adsorption capacity to PO3--4-P andNO2-N is more than NH₄⁺-N.（6） The preparation and application of the functional tourmaline ball: using diatomite as carrier andadopting the piercing-solidifying method for getting the functional tourmaline ball, after400℃hightemperature treatment, the intensity of tourmaline infrared radiation spectrum absorption of characteristicpeak and happening peak was weaken, and the phenomenon of peak position shift took place, whichillustrated the changes of crystal chemical bonds and structure and active functional group was activated,but it did not make the tourmaline of spontaneous polarization phenomenon disappear and still kept theunique characteristics of tourmaline. Just as the ultra-fine powder of tourmaline, the FTB fromhigh-temperature processing can also regulate the pH of acid and alkali solution rapidly, it had betteradsorption effect to Cu²⁺、Pb²⁺、Zn²⁺、PO₄^3--P、NO₂^--N and NH₄⁺-N in the solution. FTB can effectivelyreduce water molecules cluster size, making aquaculture water activate and also increase water dissolvedoxygen content and improve the penetration of water, soluble and metabolic ability, it has a broad prospectof application in aquaculture water treatment.（7） In the static aquaculture processing, the functional tourmaline balls （FTB） can not onlysignificantly improve the aquaculture pH value and water dissolved oxygen content （DO value） andreduce the concentration of PO3--4-P、NO2-N and NH₄⁺-N in aquaculture water; In dynamic aquacultureprocessing, FTB can greatly reduce JiFu tilapia water in the PO₄^3--P、NO₂^--N and NH₄⁺-N concentrations,whose COD value is obviously lower than those of control group and SAD group.