Application of metal wire mesh corrugated packing in production

The metal corrugated packing produced by chemical packing manufacturers has the advantages of large production capacity, high separation efficiency, small pressure drop, large control flexibility, and small liquid stagnation. It can be widely used in distillation, absorption and other unit operations, especially for difficult-to-separate materials System and heat-sensitive material system vacuum distillation process. The S W-1 and S W-2 fillers are based on summarizing the applied technology at home and abroad, adopting the value analysis method to simplify processing and save materials, so they have great practical significance. It can be used in towers with a diameter of more than 3 m, which has obvious social and economic benefits. The pressure drop of S W-1 type packing is commensurate with orifice M450, and its efficiency is slightly lower than that of CY type wire mesh corrugated packing. The pressure drop of S W-2 type packing is much lower than that of orifice plate M450 type, and the efficiency is slightly that of BX type wire mesh packing, which is higher than that of M450 type orifice plate packing. At present, most domestic manufacturers of methylamine use a 5-column continuous distillation process. Methylamine is synthesized by the reaction of methanol and ammonia on an acid catalyst under pressure. The production technology is relatively mature. The basic production process: methanol and ammonia (substance ratio) with a ratio of 1:1.5 to 4, In the presence of a temperature of 425 ~ 430 ℃, a height of 3.0 MPa and the presence of a catalyst, the continuous gas phase catalytic reaction is run to generate a mixed crude product of monomethylamine, dimethylamine, and trimethylamine, which is then continuously pressurized and rectified through a series of distillation towers Separation, deamination, dehydration, separation, can obtain the industrial products of monomethylamine, dimethylamine, and trimethylamine. Almost all the rectification towers of the methylamine unit constructed in the early stage use plate structure, although the investment is small, but the tower is tall and the structure is complicated , Installation and inspection are more difficult. We have verified that all the distillation towers use metal wire corrugated packing distillation towers, which have a specific surface area and a large open space rate, a small resistance to the tower body, high mass transfer and heat transfer efficiency, large control flexibility, and convenient installation and inspection It has the same advantages and can reduce the height of the distillation tower by one third.

The crude methylamine from the batching synthesis process enters the deamination tower, and the azeotrope of ammonia and trimethylamine is obtained at the top of the tower, which returns to the batching synthesis process, and the tower bottom liquid is sent to the extraction tower. The operating pressure of the top of the ammonia removal tower is 1.9 MPa, and the operating pressure of the cooling water of the top condenser is adjusted. The extraction tower uses fresh water for extraction. One part of the trimethylamine added from the top of the tower and steamed from the top of the tower is used as an industrial preparation process, and the other part returns to the synthesis process, and the tower kettle liquid is sent to the dehydration tower. The operating pressure of the extraction tower is 1.2 MPa, and the operating pressure of the cooling water of the top condenser is adjusted. The still liquid of the extraction tower enters the dewatering tower, the mixture of monomethylamine and dimethylamine vaporized from the top of the tower is sent to the separation tower, and the still liquid is sent to the environmental protection tower. The control pressure at the top of the dehydration tower is 0.9 MPa, and the operating pressure of the cooling water from the condenser at the top is adjusted. The mixture of monomethylamine and dimethylamine from the dehydration tower enters the separation tower, and the monomethylamine separated from the top of the tower is sent to the industrial preparation process as a finished product, and part is returned to the ingredient synthesis process; the dimethylamine extracted from the lower part of the tower is sent to the industry To the dimethylamine storage tank. The operating pressure of the separation tower is 0.55 MPa, and the operating pressure of the cooling water of the top condenser is adjusted. The kettle liquid from the dehydration tower enters the environmental protection tower, and the A is further recovered through separation to reduce the consumption of raw materials and improve the quality of wastewater.