Compared with hot ramming paste, cold ramming paste is characterized by convenient construction and controllable quality. During the construction of hot ramming paste, put the paste in the kneading pot 2-3 hours in advance and heat it to above 110 ℃ to soften the paste. At the same time, heat the carbon block group and side carbon block placed in the electrolytic cell to about the same temperature before construction. Due to the sensitivity of paste to temperature, each layer of rolling paste is required to be completed in a short time. At the same time, the rolling compression ratio of paste can only be determined through fixed technology and experience. The controllability is poor, resulting in the hidden danger of slot leakage.
Since the cold ramming paste can be constructed under the normal temperature of 15-35 ℃, it is within this temperature range in the electrolytic plant most of the time in China, even in the northern region. Generally, the new aluminum plant will choose the season under this temperature to build the furnace, and there is basically no need to take heating measures for the paste, cathode carbon block group and side carbon block. During the overhaul, because there are operating electrolytic cells on both sides of the overhaul tank, the temperature is also within this range, which is very conducive to the construction of cold island paste. Even if some areas are in the cold season, it is only necessary to put the whole bag of paste in a heated room in advance, so that the paste can maintain a balanced temperature of more than 15 degrees Celsius, and the carbon block group and side carbon blocks can be successfully constructed only when they are heated to a temperature of about 20 degrees Celsius.
In general, due to the low requirements on the length of construction time during the construction of cold rammed paste, workers can work calmly. After the completion of each layer of rolled paste, especially when the construction leg is stretched, needle densitometer can be used to check whether there is over rolling or under rolling, so as to take corresponding remedial measures to ensure that the construction meets the design quality. In addition, only cold ramming paste can realize mechanical rolling paste, which creates a prerequisite for improving the construction quality and efficiency of electrolytic cell.