Design and application of alcohol filter
To filter alcohol liquid, a good filter is the key to success. Through the analysis of the principle of quartz bed mechanical filtration, we designed a filter with filter element.
The installation position and structure of alcohol liquid filter are shown in Fig. 1 and Fig. 2. The cylinder is welded with steel pipe of – 325, one end of which is closed and the other end is fastened with cover plate. The tank is divided into two chambers by 10 mm thick steel plate according to the space distance of 2:1. A chamber of buffer solution is used to make it pass through the filter layer under pressure. The other chamber is the packing chamber, and its lower end is a support body welded by 10 mm thick and – 16 mm perforated plates. Two layers of 100 mesh stainless steel wire mesh are laid on the orifice plate, on which hundreds of steel wire cleaning balls are stacked. The outlet pipe of the alcohol filter tank is also provided with two layers of 100 mesh screen to prevent the flocs from entering the alcohol storage tank.
Application of alcohol filter
The installation position of the alcohol filter is shown in Fig. 1. After the fine alcohol pressed into the middle storage tank enters the filter, it is first filtered through the stainless steel wire mesh for mechanical screening, and 170 μ The granular impurities above m were intercepted first, and the remaining filtrate entered the clean ball filter layer.
The alcohol liquid zigzags between the pores of the filter layer, and the flocculent wax is adsorbed by the filler and retained. With the increase of flocs, the gap of filter layer decreases gradually, forming a layer of filter membrane, which promotes the generation of filtration. However, when the filter membrane thickens to a certain extent, the filtration resistance will rise (as can be seen from the pressure gauge), the filtration speed will decrease, and the surface of the filter membrane will be fractured due to uneven stress.
A large amount of alcohol liquid flows out from the crack, which causes the local flow rate to be too high and makes the suspended impurities penetrate the filter layer, resulting in the phenomenon of turbidity. Therefore, in use, when we find that the pressure at the outlet of the filter tank decreases, we should stop the filtration immediately. Open the cover plate, take out the packing, and purge with steam to make the wax melt and flow away, so as to clean the packing and enter the next working cycle.
Because the paraffin particles in the liquid alcohol will deposit in the wall, elbow and packing layer of the water cooling pipe, the water cooling temperature is too high, the gaseous alcohol can not be well condensed, and the atomized particulate alcohol can not be fully separated. This will not only reduce the alcohol production of the system, but also change the composition of the liquid copper due to the residual alcohol brought into the copper refining tower by the tower gas.
See Table 1 for comparison of alcohol quality before and after use of alcohol filter. It can be seen from table 1 that since the alcohol liquid filtration and the cold exhaust and alcohol separation measures of the process gas interrupted cooking, there is no stopping phenomenon caused by wax plugging in our plant, which has extended the effective working time of methanol catalyst. After filtration, the appearance of alcohol solution is transparent and turbidity is reduced, so it is no longer difficult to sell due to the quality of crude alcohol. The economic benefits are obvious.