There are specific temperature and pressure requirements for the storage of urea in a tank. Urea is a sensitive compound that can be affected by extreme temperatures and pressures, so it is essential to store it within certain limits to maintain its efficacy and prevent any damage or degradation.

Temperature is a critical factor in the storage of urea. It is recommended to store urea in tanks at temperatures between 10 and 30 degrees Celsius (50 to 86 degrees Fahrenheit). This range ensures optimal stability and prevents any potential reactions or decomposition. Urea can freeze at temperatures below 0 degrees Celsius (32 degrees Fahrenheit), so it is important to ensure that the tank and the surrounding environment are adequately heated in cold climates to prevent freezing and subsequent blockages.

Pressure is also an important consideration when storing urea in a tank. Although urea does not exert significant vapor pressure on its own, it is usually stored as a solution of urea and water, known as Diesel Exhaust Fluid (DEF). DEF has a freezing point that decreases as its concentration of urea increases. As a result, DEF can expand and exert pressure on the tank walls when stored at low temperatures. To accommodate this expansion, tanks usually have built-in expansion chambers or vents that allow for pressure relief.

Furthermore, it is crucial to ensure that the storage tank for urea is designed and manufactured to withstand the pressures and temperatures associated with the transportation and storage of DEF. Tanks are typically made of materials like high-density polyethylene (HDPE) or stainless steel, which offer excellent chemical resistance and are less prone to corrosion or damage.

In addition to the temperature and pressure requirements, it is necessary to handle urea carefully during storage and avoid any contamination, as impurities or foreign substances could affect the performance of urea or damage the vehicle's selective catalytic reduction (SCR) system.