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Recently, there has been lively discussion in newspapers and websites regarding the development of carbon ammonium enterprises. Some argue that such enterprises are major consumers of energy as well as significant sources of pollution. There are also views suggesting that small ammonium carbonate enterprises experience frequent safety accidents and lack guarantees for safe production; therefore, the only real solution is for these enterprises to decide to close down. However, we believe that, based on the characteristics of carbon ammonium products and the current situation of carbon ammonium manufacturers in Zhejiang, carbon ammonium remains a good product, and developing it in a manner suited to local conditions is in line with the national conditions. I. Carbon ammonium products possess remarkable resilience. Since 1958, when chemist Hou Debang and chemical engineers from Dalian Chemical Plant proposed a new process for producing ammonium bicarbonate via the carbonization method for ammonia synthesis, provinces across the country have begun to develop small-scale ammonium carbonate plants that use coal as raw material. By 1980, a total of 1,374 small ammonium carbonate plants had been built across the country, producing 8.19 million tons of synthetic ammonia and 5.53 million tons of nitrogen fertilizers in pure form, accounting for 55% of the country’s total nitrogen fertilizer production. In 2004, national small ammonium carbonate plants produced 6.72 million tons of pure nitrogen in the form of ammonium carbonate, a figure that was 30% higher than that in 1985; this accounted for 22.3% of the country’s total nitrogen fertilizer production. Despite the competition and pressure from imported and domestically produced urea over the past two decades, the production of ammonium carbonate continued to increase, indicating that there is still demand for this product in the market. 1. Ammonium carbonate is an environmentally friendly fertilizer; its long-term use prevents soil compaction. Urea belongs to ammonium nitrogen; NH4+ can be absorbed by crops and used directly to synthesize organic compounds such as amino acids, resulting in rapid fertilizer efficacy. Previously, Zhejiang farmers used ammonium carbonate when growing successive crops of late-season rice, which allowed the rice to mature about one week earlier than when urea was used. Since urea is an amide-based nitrogen fertilizer, when applied to the soil, aside from a small amount that is absorbed directly by crops, most of it is first slowly hydrolyzed into ammonium carbamate and then converted into ammonium carbonate before it can be absorbed by crops. Part of it undergoes nitration, which leads to increased loss and environmental pollution as well as reduced efficiency in utilization. 2. The conclusions drawn by the National Agricultural Fertilizer Testing Network are that, when nitrogen, phosphorus, and potassium are considered together, each kilogram of nutrients can result in an increase in grain production of 7.75 kilograms. Based on this calculation, a reasonable application of one ton of ammonium carbonate (in terms of physical quantity) can increase grain production by 1.33 tons, which is equivalent to 1.33 mu of land that can produce 1 ton of grain per year. 3. Among the various process flows for producing nitrogen fertilizers via synthetic ammonia, the ammonium carbonate production process is the shortest and has the lowest energy consumption; the CO2 emissions from ammonium carbonate production using coal as raw material are about 50% lower than those from urea production. Currently, the international advanced level for the overall energy consumption in ammonia synthesis using coal as a raw material is 46–49 gigajoules per ton of ammonia, which is equivalent to 1572–1674 kilograms of standard coal per ton of ammonia. In 2006, WeiHua, one of China’s large ammonia plants that uses coal as a fuel source, had the lowest energy consumption, at 48.82 gigajoules per ton of ammonia, or 1668 kilograms of standard coal per ton of ammonia. The average overall energy consumption per ton of ammonia for these three large coal-based ammonia plants was 1844 kilograms of standard coal. In 2006, the average energy consumption per ton of ammonia in the 12 carbonamide factories across the small nitrogen fertilizer industry in Zhejiang Province was 1,606 kilograms of standard coal, which is significantly lower than the energy consumption levels of larger enterprises. With the further implementation of the 8 energy-saving measures promoted by the China Nitrogen Fertilizer Industry Association, the overall energy consumption of ammonium carbonate products can be reduced further. 4. Ammonium carbonate has the lowest price per kilogram of nitrogen nutrient. Urea contains 46% nitrogen, which is 2.6 times that of ammonium carbonate. Considering commercial factors, agricultural supply companies and agricultural departments in Zhejiang Province usually set the price ratio between urea and ammonium carbonate at 3:1; however, in reality, the price of ammonium carbonate is always much lower than this ratio. Ammonium carbonate plants are located near consumption areas, and convenient transportation during the peak fertilizer use period facilitates farmers to purchase them locally. 5. Ammonium carbonate enterprises, which have downstream products closely related to the ammonium carbonate production process, have now become suppliers of basic chemical raw materials and are able to integrate well with local industries. II. Safety and environmental aspects of ammonium carbonate production. With the development of urbanization, some ammonium carbonate manufacturing enterprises are not far enough away from residential areas, objectively creating safety hazards. But these enterprises can still continue to develop through relocation. Safe production relies on effective management; although some older enterprises fail to meet the requirements of safety technical standards, safety hazards can be eliminated in a timely manner by strengthening safety education for both new and existing employees, as well as implementing regular safety inspections and monitoring systems. At present, all the small ammonium carbonate factories in Zhejiang meet the requirements for safety production licenses, and have achieved safe, orderly, and sustainable development. III. Environmental protection in ammonium carbonate production. At present, all carbon ammonium enterprises in Zhejiang have implemented environmental protection measures such as comprehensive utilization of recycled water and sulfur recovery. Zhejiang has strict environmental standards; the ammonia nitrogen level in wastewater discharged must be ≤15 milligrams, and all enterprises are able to meet these requirements. Some of them have even achieved zero wastewater discharge. IV. Under the new circumstances, large, medium, and small nitrogen fertilizer producers should develop in harmony. Ammonium carbonate products are suitable for China’s national conditions, have high demand in agriculture, and contribute significantly to energy conservation and emission reduction. However, due to various reasons, ammonium carbonate manufacturers are currently facing considerable difficulties. After the mid-1980s, in the face of competition from imported urea, domestic urea manufacturers accelerated their production, which led to a relative decline in the share of carbon ammonium in the total production of nitrogen fertilizers in the country. The rational layout of the fertilizer industry is essential for coordinated development. Large and medium-sized urea manufacturers are located near the sources of raw materials, allowing for long-distance transportation to supply the entire country ； Urea ammonium carbonate plants should be strategically located in areas where the conditions permit; an appropriate scale for such plants is around 40,000 to 80,000 tons per year of synthetic ammonia produced. These plants should also cooperate with local agricultural departments to establish agrochemical service centers that provide guidance and support for soil testing and fertilization practices in rural areas, thereby improving fertilizer utilization rates and reducing losses during fertilizer use as well as environmental pollution.