Abstract: A method for filling carbide blades in cutter head by using a carbide blade cutter head filling device. The carbide blade cutter head filling device includes a feeding unit, a storage unit, a loading unit and a discharging unit which are arranged successively. The output end of the feeding unit is matched with the input end of the storage unit through the guide mechanism. The output end of the storage unit faces a conveying tray of the loading unit. The conveying tray is provided with a plurality of group of transition holes for accommodating blades. A receiving mechanism for accommodating a cutter head is arranged below the falling pull plate of the discharging unit. The falling pull plate adjusts the communication and isolation between the transition hole and the cutter head in the receiving mechanism by changing the relative position of the falling pull plate and the transition hole.

Abstract: A method for preparing isophorone diisocyanate by (1) reacting isophorone with hydrogen cyanide in the presence of a catalyst to obtain isophorone nitrile; (2) reacting the isophorone nitrile obtained in step (1) with ammonia gas and hydrogen in the presence of a catalyst to obtain isophorone diamine; and (3) subjecting the isophorone diamine to a phosgenation reaction to obtain the isophorone diisocyanate, wherein the content of impurities containing a secondary amine group in the isophorone diamine that undergoes the phosgenation reaction in step (3) is ?0.5 wt. The method reduces the content of hydrolyzed chlorine in the isophorone diisocyanate product, improves the yellowing resistance of the product, and the harm due to presence of hydrolyzed chlorine in the product is reduced.

Abstract: A polyisocyanate composition, a preparation method therefor and an application thereof. The value of the mass content of alkaline hydrolyzed chlorine minus the mass content of water hydrolyzed chlorine in the polyisocyanate composition is 0.1 ppm-100 ppm. The mass content of the alkaline hydrolyzed chlorine is the mass content obtained by calculating halogen dissociated under alkaline conditions and/or halogen dissociated under a temperature condition of 100° C. or more as the relative atomic mass of a chlorine atom.

Abstract: A method for preparing isophorone diisocyanate by (1) reacting isophorone with hydrogen cyanide in the presence of a catalyst to obtain isophorone nitrile; (2) reacting the isophorone nitrile obtained in step (1) with ammonia gas and hydrogen in the presence of a catalyst to obtain isophorone diamine; and (3) subjecting the isophorone diamine to a phosgenation reaction to obtain the isophorone diisocyanate, wherein the content of impurities containing a secondary amine group in the isophorone diamine that undergoes the phosgenation reaction in step (3) is ?0.5 wt. The method reduces the content of hydrolyzed chlorine in the isophorone diisocyanate product, improves the yellowing resistance of the product, and the harm due to presence of hydrolyzed chlorine in the product is reduced.

Abstract: A heater for heating and vaporizing droplets in gas stream, comprising a heater housing and a heater body located inside the heater housing, wherein the heater housing is provided with an airflow inlet and an airflow outlet, the airflow enters into the heater housing via the airflow inlet, flows through the heater body, and then is discharged via the airflow outlet; the heater body comprises a stereoscopic network structure formed by interweaving one or more electrical heating wires. The use of the heater and a method for preparing isocyanate using the heater. The heater has a simple structure, a low pressure loss, uniform heating and a high heat utilization ratio during preparing isocyanate.

Abstract: A heater for heating and vaporizing droplets in gas stream, comprising a heater housing and a heater body located inside the heater housing, wherein the heater housing is provided with an airflow inlet and an airflow outlet, the airflow enters into the heater housing via the airflow inlet, flows through the heater body, and then is discharged via the airflow outlet; the heater body comprises a stereoscopic network structure formed by interweaving one or more electrical heating wires. The use of the heater and a method for preparing isocyanate using the heater. The heater has a simple structure, a low pressure loss, uniform heating and a high heat utilization ratio during preparing isocyanate.