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Pujie Nenghua develops carbon-ammonia capture device to solve crystallization problem in acidic gas pipelines Author/Source: Sinochem News Network Date: May 18, 2022 Clicks: 1 On May 13, reporters learned from Pucheng Clean Energy Chemical Co., Ltd. that the carbon-ammonia capture device developed by this company enables the extraction of ammonia from methanol in low-temperature methanol washing systems, thereby solving the technical issue of carbon-ammonia crystallization in acidic gas pipelines and filling a gap in the coal chemical industry both domestically and internationally. It is reported that the shifted gas entering the low-temperature methanol wash from the shift unit contains trace amounts of ammonia; when this amount accumulates to a certain level, carbon-ammonium crystals tend to form in the acidic gas pipelines, which are primarily composed of carbon dioxide and hydrogen sulfide, under the existing temperature and pressure. These crystals can block the pipelines and equipment, affecting the efficiency of methanol regeneration. As a result, the hydrogen sulfide concentration in the purified gas exiting the methanol wash unit becomes excessive, leading to the poisoning and deactivation of the synthesis catalyst. At the same time, the acidic gases generated by the low-temperature methanol washing system cannot be sent outside, which forces the sulfur recovery system to operate at reduced capacity and also causes certain environmental pollution. To this end, the R&D team at Pujien Energy Chemical Company’s methanol division collected a large amount of historical operation data, conducted research, and innovatively introduced the new concept of a carbon-ammonia capture device. By repeatedly hypothesizing models and conducting practical verifications, the schematic diagram of the carbon-ammonia capture device and process flow was determined and finalized. This device utilizes the principle of \"throttling effect\" to replace traditional methods such as local methanol substitution and thermal washing of acidic gas pipelines; by using internal energy to reduce temperature, it facilitates carbon-ammonia crystallization, thereby enabling its capture. On November 5, 2021, “A method for the capture and recovery of ammonia in low-temperature methanol washing systems” was granted a **patent license. After the carbon-ammonia capture unit was put into operation in June 2020, it underwent multiple adjustments and optimizations as well as internal component upgrades; by January 2021 it had reached stability. It has been operating continuously for 13 months to date, showing significant energy-saving effects. According to statistics, at least 2,000 tons of methanol can be saved each year, which equates to cost savings of around 4 million yuan.