Plate Heat Exchanger Fouling Characteristics Of Microorganisms On Calcium Ion Environment

Due to the plate heat exchanger in high thermal efficiency, compact structure,easy to remove many characteristics, such as cleaning, widely used inindustry-agriculture or other fields for many years. But this kind of heat exchangerexist fouling problem, the presence of dirt will reduce the heat transfer coefficient,caused great waste of resources and economic losses. In this paper, CaCl2and thetypical microorganism in circulating cooling water of iron bacteria as the researchobject, the plate heat exchanger fouling characteristics and experimental research ofparameter change rule of water quality. It will provide a certain theoretical basis forpractical water.At first, this paper studies the calcium ions in the environment of iron bacteriain plate heat exchanger fouling and pure iron bacteria contrast in the amount offouling in heat exchanger. The experimental results show that under the condition oftwo kinds of iron bacteria in exist induction period in the plate heat exchanger, andunder the environment of calcium iron bacteria induction period of relatively pureiron bacteria induction period change is not big, under the environment of calciumiron bacteria in the plate heat exchanger fouling resistance asymptotic value is higherthan that of pure iron bacteria asymptotic fouling resistance value. But within acertain range change of calcium ion concentration has a little influence on theasymptotic fouling resistance valueSecond, under the environment of calcium ion fluid was studied in differenttemperature, velocity and concentration of iron bacteria the scaling law of plate heatexchanger. The experimental results show that as the low temperature circulationcooling water inlet temperature increases, the iron bacteria Ca2+environmentinduction period shorten but there was no significant effect on the rate of fouling, thefouling thermal resistance of the asymptotic value reduced. With the increase of fluidvelocity, Ca2+environment of iron bacteria had no obvious effect on the rate withfouling induction period, the asymptotic fouling resistance value. With the increaseof concentration of iron bacteria, iron bacteria Ca2+environment induction periodhad no obvious effect on the rate and scale, fouling resistance decreased asymptoticvalue.Third, the iron bacteria was studied of calcium ions in the plate heat exchangerchange rule of water quality parameters. Results show that with the increase oftemperature, calcium ions in the environment of iron bacteria bacterial count toreduce gradually, the lower the pH, the higher the conductivity. As the speed increases, calcium ions in the environment of iron bacteria number increased, pHreduced gradually, the conductivity increased. With the increase of concentration ofbacteria, calcium ions in the environment of iron bacteria, the lower the pH, thehigher the conductivity.