Daqing Petrochemical’s **problem with urea caking in summer**
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China National Chemical News: From July 1 to 6, the fertilizer plant of Daqing Petrochemical Company used a method involving the addition of 37% formalin solution to the urea evaporation system. This approach enabled an increase in the strength of the urea particles within the limits specified by GB 2440-2001; as a result, the amount of dust generated by the product was significantly reduced, and its quality improved further. The quality challenges faced in urea production during hot seasons have been **. Since the capacity expansion and renovation of the plant’s urea production unit in 2005, its production capacity has increased from 480,000 tons to 800,000 tons, while the main production facilities remain unchanged; the equipment utilization rate has consistently been at its maximum level. Since the onset of summer this year, due to the high temperatures, the temperature of the urea pellets produced has remained high, and dust levels have also increased significantly. Furthermore, during processes such as storage of excess inventory, transportation, and stacking in bags, heat accumulates and does not dissipate easily, which leads to a significant increase in the caking of urea products; **this affects the brand image of Kunlun-brand urea. To address this issue, the factory established a task force and adopted the method of adding an appropriate amount of formaldehyde during the urea production process, thereby preventing urea particles from absorbing or releasing moisture quickly and ensuring stability in the moisture content of urea. This approach helps to reduce the problems of caking and pulverization in urea products. It is reported that after adding formalin solution to the urea production process, the formalin content in the resulting urea is around 0.25%. The diameter of the urea particles ranges from 0.85 to 2.8 millimeters, and the strength of these particles increases by more than 40%. Additionally, the amount of dust generated during production decreases by about 30% compared to before, which helps to address the problem of caking in urea products and improves their quality.
Urea combined with formaldehyde has been widely used for some time, and it is effective to a certain extent.
I’m very curious to know where formaldehyde is added in the urea production plant Is it in the urine tray? Where is the aqueous solution fully circulated?
Daqing must be feeling frustrated too with this weird weather this year, haha
I would like to know how the urea production facility at Daqing Petrochemical was expanded and what its current operating conditions are
This post was last edited by Luo Hu 15185080221 on 2010-7-19 08:48. A parallel medium-pressure system was added; the liquid coming out of the synthesis tower is directly routed to this medium-pressure system. The ammonium methanate liquid from the low-pressure circulation system is first sent to the medium-pressure system, and from there it is pumped to the high-pressure system using the newly added turbine centrifugal ammonium methanate pump. Most of this liquid goes to the scrubber, while a small portion goes to the ammonium methanate condenser. The low-pressure ammonium methanate system and related pipelines are still retained as backups for when the system is started up or in case of problems with the medium-pressure system. The ammonia pump has been replaced with a motor-driven centrifugal pump, and a new evaporator was installed, but it’s hardly being used. The operational results aren’t as good as I had expected; according to their data, the fluctuations are quite large
Reply to 6# ythwangbo: Hehe, may I ask what the main problems with the device are?
Reply to 7# htcfkq: I think it’s a matter of concepts and skills. Their roles are clearly defined, the technical equipment isn’t interconnected, and those in charge of the manufacturing process don’t understand the equipment. Moreover, there is inertia among the staff, as they can rely on CNPC as a backstop – their salary hardly changes whether they drive or not. I’ve seen some of them driving while holding books
Reply to 8# ythwangbo: It’s like trying to understand an elephant by touching its parts – those cards are meant for operational use. The technical knowledge needed for production is already in the operators’ minds; the cards are there simply to reflect the concept of controlled production. Although state-owned enterprise management is outdated, it maximally safeguards the interests of all stakeholders
Also, I don’t know who posted this here; we added formaldehyde simply because it’s been unbearably hot this year! Since the company’s management has demanded it, we have to carry it out. But in my opinion, adding formaldehyde doesn’t involve any real technical complexity, and many companies such as Yuntianhua have already done this! The original poster’s post must be an excerpt from a press release!
All I know is that on that day, during the middle shift, ammonia was being introduced using a centrifugal ammonia pump. Sealing water was poured in first, and the control room staff directed the operations based on the procedures. The pump room was responsible for adding the sealing water, with the goal of adjusting the pressure difference to 2 kilograms through the backpressure control valve. It should be noted that without ammonia flowing through the system, the pressure of the sealing water was only around 20 kilograms, so it was impossible to reach 2 kilograms. Eventually, the control room staff cursed at those in the pump room, who in turn cursed back at them; it was only after calling a technician that things were clarified