First, select process conditions to reduce methanol consumption.
Second, choose equipment that meets process requirements to make formaldehyde production better.
1. The oxidizer in the Silver Contact Formaldehyde Plant is the key equipment for methanol dehydrogenation. Its rationality directly affects the level of methanol consumption. If there is a good furnace of catalysts combined with good process conditions, but the lack of good equipment alone will also result in high acidity of the finished product and high side reactions (high CO and CO2 content in the tail gas), which will affect the product. Quality and unit consumption. In addition, the service life of the oxidizer is also an important issue. According to experience, the center distance between the heat exchange tubes of the oxidizer, the distance between the porous plate and the tube plate of the catalyst, the residence time of the reaction gas in the high temperature region, the position and number of the openings of the preheating boiler rising tube, The thickness of the board and the proper addition of auxiliary facilities will determine the unit consumption and quality of formaldehyde.
Silver Contact Formaldehyde Plant
2. Energy consumption is also an important technical and economic indicator. The ideal power consumption of a reasonable formaldehyde unit should be below 35Kw / t, or even below 25Kw / t. To achieve this target process:
a. At present, the more traditional heat source of evaporator heating in the Formaldehyde Production Processcomes from the hot water in the cooling section of the oxidizer, but due to the incomplete water quality treatment, long-term operation will cause the scaling phenomenon of the cooling section and the heating section of the evaporator And thus affect the heat transfer effect of heat exchange equipment. Heating the evaporator with formaldehyde at the bottom of the tower overcomes the thermal resistance generated by scale, ensures long-term good operation of the oxidizer and the heating section of the evaporator, and saves energy consumption of the hot water pump.
b. The length of the drive cycle is determined by the conversion activity of the catalyst and the resistance of the system. System resistance will not only limit the device's ability, increase energy consumption, but also shorten the drive cycle. Each start and stop consumes a certain amount of additional methanol, affecting unit consumption. Therefore, the structure of the equipment should be carefully designed and improved: the resistance of the evaporator is mainly determined by the difference between the position of the air inlet pipe and the liquid level of the evaporator. Generally, the heating tube section of the evaporator is 500 ~ 600mm high, and the opening of the air pipe is about 400mm away from the tube sheet, so the total pressure drop of the evaporator is about 700 ~ 800mm / H2O. If the proper heating method is used to reduce the height of the heating section and arrange the distribution of the air inlet pipe, the pressure drop can be reduced by 100 ～ 200mm / H2O; Control in the most ideal position.
3. Electrolytic silver catalyst is very sensitive to the pollution that raw material gas may bring in, and it will directly affect the reaction conversion. Therefore, it is necessary to purify the raw material vapor. The ternary gas filter is the last line of defense. Its structure and paving quality have a great impact on production. The paving of the filter not only requires low resistance, but also requires good filtering effect. There are no leaks to meet the requirements. We are Formaldehyde Production Plant, welcome to consult.
