Initial startup boiler heating for hydrogen production plant
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Dear sea friends, how do you carry out temporary chemical dosing when starting up your hydrogen production units for the first time? What size of pump is used for temporary chemical dosing in a 40,000-unit hydrogen production system? Add the chemical using that pipeline? Thanks first
Use a normal dosing pump with the device; only the dosage is larger. Sodium hydroxide and trisodium phosphate are used in a certain ratio, and the respective dosages as well as the dosing intervals are determined. After diluting with deoxygenated water, the dosing pump can deliver the medication by operating at 100% of its stroke capacity.
I see that according to the operating procedures, 600 kilograms of coating agent are required; when will it be necessary to add more using the dosing pump?
The amount of chemical added wasn’t calculated correctly; it’s not that much. With two pumps working continuously, it will take about 20 hours to add the entire amount.
I checked what others have done; my calculation shows a total of over 300. 4*40*2=320 kg. But I saw a case from a Sinopec plant, and that made me wonder as well
I roughly estimate that about 400 kilograms of chemicals are needed for a hydrogen production boiler with a capacity of 40,000 cubic meters; your calculation is pretty accurate.
Even at 400 kilograms, the combined output of your two dosing pumps is less than 1 cubic meter; there’s no way you have that much time to wait and use a metering pump to add chemicals
No, you can just put the medicine in the steam drum in advance – wasn’t that company in Guangrao charging 40,000 for it?
Table 4: Dosage of alkali for boiling (kg/ton of water). Boiler cleanliness: I, II, III. Sodium hydroxide: 2–3, 3–4, 5–6; Trisodium phosphate: 2–3, 2–3, 5–6. For boilers with severe dirt and rust, the dosage specified in the table may be increased by 50%–100%. 3.2.3.2 Method of adding chemicals: The concentration of the chemical solution should be around 20%. NaOH can be added in its calculated amount all at once, while Na3PO4 can have 50% of the calculated amount added first, with the remaining 50% being added during the furnace heating process. Before adding chemicals to the boiler, the drum should first be filled with water up to the lowest visible water level.
First, at low pressure, use a temporary dosing pump (usually an air-operated diaphragm pump) to add 80% of the required dosage into the steam drum, and then use a dosing metering pump to add the remaining amount precisely