Research On Biodegradation And Its Kinetics Of Water-based Lubricant

In the paper, the background of thesis is illustrated and the previous study of the thesis is overviewed. Then, the relevant elementary knowledge of water-based lubricant and biodegradation is introduced.Based on the elementary knowledge, study of experiment is made from two sides. One is that sample fluid is biodegraded in the active sludge and the other is that bacteria growth of sample fluid is determined in the course of the simulated working. The growth of bacteria reflect the situation of biodegradation in the sample fluid, to some extent. The result of experiment is indicated as follows.When sample of water-based lubricant is diluted for over 100 times, it can be biodegraded well in the acclimated 6 weeks' active sludge of city. The ratio of biodegradation is more than 60%; When glucose is added into system, the ratio of biodegradation increases obviously; The neutral pH is good to biodegradation; At 30掳C, diluting 200 times, adding appropriate amount of nutritive substance, sample fluid is biodegraded very well in the active sludge system whose concentration is 1580mg/L. In this condition, biodegradation follows the first order kinetics equation , the rate constant (K) of biodegradation is 0.375, kinetic equation isCf = 608.29e-0375t. In fact, it is the biodegraded reaction which have decimal order.Phenol is of the very good bacteriostatic performance. In the 9 weeks , when the content of phenol is 2%, the requirement of bacteriostatic performance can be met and the content of phenol in the sample fluid keeps in about 1.3%, which can gain the better economical efficiency and environment performance. The growth ofbacterial follows the logarithm model which is y= 621.9e0.11x -483.0 .At thesame time, the relation of bacterial number and pH in the fluid is discussed. It can be showed approximately in Y = -546.1 X + 3879.2.