Analysis of treatment measures for oily wastewater in refining edible oil
The outsourcing of crude oil by entering the filter tank, edible oil refining machine, remove all kinds of impurities in crude oil into the heater, heated to a certain temperature, the quantitative and phosphate together into the mixer. After full mixing, it enters the hydration reactor, and then neutralizes the mixture by adding alkali. After reaction, the oil and soap foot are separated by centrifuge. The light phase oil enters the mixer and is washed twice by adding hot water. Then the soap water is removed by centrifuge. The soap foot pumps the soap foot tank, and finally the clean oil comes out. The air dryer is dehydrated and enters the next stage.
Alkali refining bleaching degumming heating after drying and mixing clay decolorization into bleaching tower. After bleaching, the oil pump is filtered into the blade filter (three alternately filtered). Back to the oil filter in turbid bleaching tower after filtration, oil decolorization by the security filter sent to the deodorization process. After deodorization, the oil enters the heat exchanger for heat transfer. The heat exchanged oil is heated by the heater to the temperature required for deodorization and then goes into the pre-deodorization tower for deodorization and thermal decolorization. Most of the free fatty acids are rectified out of the pre-stripping tower and cooled by a cooler after heat transfer with the decolorized cold oil.
At present, the most important and stable method to treat vegetable oil wastewater in China is biological method, which can degrade oil effectively. Compared with physical method, it has obvious treatment effect and less secondary pollution. At present, the utilization rate of biological method in China has reached 80%. Biological treatment includes anaerobic biological treatment process and aerobic biological treatment process. According to the advantages and disadvantages of the bio-treatment process of oily wastewater and the characteristics of the refinery process oily wastewater, combined with its own economic benefits, the enterprise finally plans to adopt SBR process. The feasibility and effect analysis of SBR method SBR is the abbreviation of sequencing batch activated sludge process. The SBR process consists of a batch of reactors operating in a certain order. When treating wastewater, the operation process of each batch reactor includes five stages: water inflow stage (or water filling stage), reaction stage, sedimentation stage, drainage and sludge discharge stage and idle stage. Intermittent operation is the main characteristic of SBR.
The so-called sequential batch has two meanings: one is that the operation is carried out in a sequential and intermittent manner in space. Because most of the sewage is discharged continuously and the flow fluctuates greatly, at this time SBR is at least two or more pools, and the sewage enters each reactor sequentially, and the relative relationship between them is secondary. The order is batch; two is the operation of each SBR reactor in time is arranged in order of intermittent operation, according to the general operation order is divided into five stages. Among them, from the influent, reaction, sedimentation, drainage and sludge discharge to idle end is a running cycle.
In a cycle of operation, operation time, reactor within each stage of the volume of the mixed liquid and the changes of the running state can be flexible according to the specific nature, sewage effluent quality and operation function etc.. For a single SBR, there is no space to control obstacles, only to control and transform effectively in time, which can achieve a variety of functional requirements, the operation is very flexible. Because SBR has at least two or more pools, the effluent from this project can be considered as continuous discharge.