How should high-profile water systems be managed? (CO2 stripping method)

Keep the temperature at a high level between 120 and 130°C; it can be slightly higher during startup and shutdown. The previous time, the temperature difference was controlled at around 7°C. Last edited by lxq700918 on 2009-2-14 23:17.]

On the second floor, you mentioned temperature control; in fact, there is also flow control, water quality control, as well as emissions and flushing procedures during startup and shutdown, etc. It also includes various controls related to the enterprise itself. I hope you can provide more detailed information on this! !

Let each person say a few words: A split-control system is planned to be added at the outlet of the cooler on the double-track line with high water flow, in order to improve control efficiency and reduce the workload of production operators.

Hehe, thanks to the person on floor 3 – this relates to process control; thanks for your participation! ! !

We don’t have any; everything is controlled through on-site operations. There was already a mature control system in place; haha, I thought it was an original idea of our leader: lol

This is already a mature control system! By the way, how is water quality control managed at your place? Is it emitted after parking?

When starting up or shutting down the system and operating at high water levels, remember to open the balance pipe, and make sure all air is completely removed.

Water quality management includes adjusting the temperature of water and condensate. The chloride content in both condensate and high/low-pressure water must not exceed 0.5PPm; otherwise, it must be replaced. The conductivity of the condensate is not higher than 30 us/cm. 2 Regularly analyze the levels of ammonia and chloride ions; it was originally done once a month, but after an incident in which the chloride ion level exceeded the limit, the frequency was changed to once a week. 3 The condensate at the bottom of the shell side of the high-pressure washer should be drained regularly, once per shift, for 30 minutes each time. 4 Parking emissions depend on the circumstances. This post was last edited by 1025199692 on 2009-3-10 22:05]

The suggestions for the third floor are as follows: If financial constraints are not a concern, it is recommended to: 1. Replace the high-temperature water supply valve with a remotely controllable regulating valve. 2. Use regulating valves for the jacket steam used during startup and shutdown; this way, the personnel on site only need to operate the drain valve during these processes. 3. Install a filtering device at the inlet of the circulating water going into the high-temperature water heat exchanger, to prevent debris in the circulating water from entering the heat exchanger and affecting its efficiency. 4. Add a regulating valve at the outlet of the circulating water leaving the high-temperature water heat exchanger, in order to control the temperature of the high-temperature water. 5. The supply temperature for high-temperature water is generally between 113 and 120 degrees; it can reach over 130 degrees during startup and shutdown, with a flow rate of around 390

Management and control of the high-pressure water system: 1. The chloride content in the high-pressure water should be analyzed regularly (on a weekly basis), and it must not exceed 0.5PPm; otherwise, the water must be replaced. 2. During operation, exhaust is required for each shift; even when the flow rate is unstable, it is necessary to pay attention to exhausting gas to ensure that the flow rate remains within the normal range at all times. 3. Depending on changes in the system, pay constant attention to controlling the temperature of the high-pressure water, especially to prevent the temperature of the high-pressure effluent from dropping below 155 degrees. (In our process, the high-pressure water is no longer involved in the circulation cycle.) 4. Strictly control the pressure changes in the high-pressure water system to prevent the explosion-proof plates from breaking due to overpressure. This post was last edited by ymtuegj12 on 2009-2-15 11:06.]

You are referring to the process of establishing a high-pressure water system, during which it is necessary to remove air from the system. What measures are taken for refilling fluid and removing air during normal operation?

We have adopted your methods 1, 2, and 3 here: we analyze the ammonia ion concentration on a weekly basis and carry out regular discharges. By discharge, you mean the release of condensate from the bottom of the high-pressure cooling shell side; this refers to the release of chloride ions from the low-pressure steam drum. Do you also carry out regular discharges for the high-pressure water?

Your suggestion is good, but fertilizer companies are currently facing tough times; managers in our company are likely not to go ahead with such an investment at this stage. Is the water supplement added using a steam condensate pump or some other type of pump? By the way, does your high-pressure water system have any pressure limits?

First of all, thank you to the moderator for your participation; I would like to express my gratitude once again! ! ! For items 2 and 4, we use long-term fluid replenishment and gas removal here; this is achieved through a constant-pressure tank, which allows for continuous fluid replenishment while also eliminating excess gas from the water. Where does the gas that is removed end up going? (Here, the steam is discharged into the medium-pressure steam saturator.) There’s also point 3: your high-temperature water is no longer used as a heating source for the distillation tower in the low-pressure circulation system. So, do you use low-pressure steam or medium-pressure steam? And what is your steam consumption? Once again, thank you for your participation! ! !

The high-temperature water heating source is removed from the low-pressure distillation tower, and it is generally replaced with low-pressure steam. Since there is an excess of low-pressure steam produced internally, and its corresponding saturation temperature is 140°C, which is sufficient as a heat source.

For high-pressure water systems, we focus mainly on the following aspects: 1. Adjusting the pressure of the high-pressure system to reduce the effectiveness of venting from it. Lowering the temperature of the hot water will inevitably enhance the absorption effect of E203. The extent to which the temperature should be reduced depends, first, on the crystallization temperature of the material and the explosion range of the inert gas in the system, and second, on the issue of waste heat utilization. The high-temperature water coming out of E203 is first sent to the first section of the evaporation system to heat the urine; under controlled conditions of discharge in the high-pressure system, the temperature of this high-temperature water is adjusted to be as close as possible to its upper limit. The premise is that the venting from HV2201 is low. 2. The issue of high-pressure water pump vaporization. Here, we do not discuss vaporization of the pump due to mechanical reasons; instead, we consider it from the perspective of water temperature and the asymmetry in equilibrium pressure. If the pressure in the pipeline network is lower than the equilibrium pressure corresponding to the high water temperature, then the water will flash and cause cavitation in the pump. The main causes of this situation are: after the system starts operating, the steam jacket used for heating water is not closed or there is air leakage ； As a result of the pressure balance being disrupted, the steam pressure in the steam drum dropped suddenly, falling below the pressure in the high-pressure water network; this caused some of the high-pressure water to flow into the steam drum, reducing the amount of water that reached E203. As a consequence, the water temperature inside E203 rose rapidly, leading to vaporization ； Pipeline leaks; 3. Blockages in the process pipelines: It is easy to determine whether there is a blockage in the heat exchange tubes or liquid delivery tubes inside E203 by checking the pressure of the high-pressure system, the liquid level and pressure in the absorption tower, as well as the temperature difference between the inlet and outlet water of E203. To prevent crystallization-induced blockages, it is necessary to avoid sharp fluctuations in the temperature of the heating water, and to keep the temperature of the process medium below the crystallization temperature. In our system, this can be problematic during startup, as no material is supplied for evaporation; the heat from E203 is removed by the heat exchanger. However, once evaporation begins with vacuum application, a large amount of water in the urea flashes off, absorbing heat and causing the temperature of the heating water to drop rapidly. Therefore, it is essential to reduce the heat transfer capacity of the heat exchanger promptly ； Handling of vaporization in the methamine pump: When the methamine pump vaporizes and is unable to deliver methamine liquid to E203, this causes the pressure in the high-pressure system to rise. At the same time, as less dilute methamine liquid enters, the concentration of methamine liquid in E203 increases. If, in such a situation, the temperature of the high-pressure water is reduced in order to lower the high pressure, the likelihood of crystallization becomes very high. After the system is shut down, thorough flushing and discharge of E203 take place, along with the activation of the jacket steam. 4. Establish a high-pressure water process to prevent explosion-proof version detonation. The main task is to thoroughly exhaust air; after connecting the balance pipes, jacket steam is then introduced.

There is pressure control, usually between 0.77–1.2 MPa. It would be ideal to have fully automated production with water replenishment via a condensate pump; of course, this also depends on economic considerations. Last edited by Durian on 2009-2-16 00:50.]

Regarding your point that the system is very practical, I still have a few questions: 1. \"The high-temperature water coming out of E203 is first sent to the first section of the evaporation system to heat the urine.\" As the heat source for that evaporation heater, what are the control values for the inlet and outlet temperatures of this high-temperature water (that is, the temperatures of the cold water and hot water)? At the same time, can high-temperature water, used as a heat source for heaters, meet the requirements of production? Could you provide parameters such as the flow rate of your high-temperature water, the heat exchange area of the evaporation heater, etc.? Thank you in advance! 2. Regarding the vaporization of high-pressure water, which leads to a reduction in the amount of water within the entire high-pressure water system, how do you control the replenishment of water and the removal of air? Could you explain it in detail? I mainly want to do a comparison, hehe! 3. When using high-temperature water as a heat source for an evaporation heater, it is necessary to pay close attention to the adjustments made before and after the evaporation feed, as well as when adjusting the system’s flow rate. I agree with what you mentioned regarding \"blockages in the process pipelines\"; after all, the process flow for each system is different, and there may be some variations in operation. 4. How do you ensure the proper pressure in your high-pressure water system? This is basically the same as the process of replenishing water and releasing air from the system. I hope you can provide more details on this, haha! There’s a lot of nonsense, just to discuss this issue clearly! ! ! This post was last edited by ymtuegj12 on 2009-2-17 11:04.]

Hehe, do you mean the pressure control you’re referring to is the outlet pressure of the high-pressure water pump? If it’s 0.77 MPa, isn’t the pressure a bit low? Can it meet the production needs?

The key control parameter for high-temperature water is the temperature of the incoming water; generally, the temperature difference is between 17 and 20 degrees. There is a limit on the temperature of the incoming water – it is usually 130 degrees during startup and shutdown, while during normal operation it ranges from 115 to 120 degrees. This value is adjusted according to the load level; generally, the higher the load, the lower the temperature. Some manufacturers set this temperature at 113 degrees. Although the design temperature is 90 degrees, no manufacturers have yet been known to attempt to maintain such a low temperature; this is done both for safety and explosion prevention reasons, as well as to avoid blockages caused by crystallization. Due to the relatively high temperature of the hot water, vaporization occurs during cyclic operation, which affects heat exchange; therefore, the exhaust valve at the higher point at the inlet is usually left slightly open to allow continuous venting, and the drain valve of the medium-pressure saturator is also left slightly open to supply liquid, in order to ensure an adequate flow rate. Flow rate is also an important parameter for reference. Furthermore, a high temperature of the temperature-regulating water can also cause scaling of the cooling water inside the cooler; this should be cleaned during maintenance to prevent it from affecting heat exchange and preventing the system from being able to handle load. The control of high water pressure cannot be generalized, as different manufacturers use different pressure measurement points, which results in varying pressure readings. However, the pressure must remain below the threshold that the explosion-proof plate can withstand, and it should be kept within a reasonable range to prevent the plate from breaking. To prevent corrosion, deionized water must be used for filling the high-pressure water system; the chloride ion content must be strictly controlled, with analyses conducted weekly to ensure it remains within acceptable limits.