Application-based solutions: safe production of fertilizers with leser safety relief valves
In order to harvest the maximum amount possible from the limited available crop land, fertilizer is needed. Producing fertilizers is a complex process, where air, hydrocarbons and water are processed to create ammonia and then further to urea – the core product of fertilizer plants. Read further for the special requirements of this industry for safety relief valves and the application-based solutions LESER is able to offer.
Our customer's plant produces a preliminary fertilizer product on three lines. The total production capacity is about 4,000 tons of urea per day. This plant works with very high pressures (up to 200 bar/ 2.900 psig) and high temperatures (up to 200°C / 392°F). As such, the product tends to crystallize, therefore bonding to the material of the safety relief valve; this threatens the reliability of the valve function. Another requirement is, to increase the operating pressure and with this the productivity of the plant. This made it necessary to precisely control the tightness and response characteristics of the safety relief valve. Based on the plant and application requirements, LESER selected the API Type 525 Series with Urea Synthesis Design together with one LESER supplementary loading system.
LESER delivered three Type 526 safety relief valves in Urea Synthesis Design to protect the urea-synthesis reactor as well as one supplementary loading system for each of the three customer’s lines. LESER has more than ten years of experience in melamin production with steam purging on a safety relief valve to avoid crystallization. This technology was the basis for the innovative steam purging for Urea Synthesis Design. LESER delivered all safety relief valves in a special stainless steel incl. quality material certificates for nozzle, disc and body as well as a corrosion test in an acid bath for high-alloyed materials. The supplementary loading system allows for a significantly higher operating pressure at the plant. At the same time, the tightness of the safety relief valves up to the set pressure is guaranteed. Through shorter opening and closing times the media loss is limited. An additional challenge was to protect the supplementary loading system against the crystallization of the medium; this challenge was solved by using a manifold as a shield.
Customer Advantages: No Technically Comparable Safety Relief Valve Solution in the Market Offered Competition
LESER developed this individual safety relief valve design to extend maintenance intervals and to increase the operating pressure of the plant. This results in a significant increase of plant efficiency. Currently there is no technically comparable safety relief valve solution in the market offered by the competition. In addition, we were able to support the customer with short delivery times due to large local stock and cooperation with suppliers.
Our Urea-designed safety relief valves are sized according to the licensor Stamicarbon; we are able to comply with the requirements of other licensors upon prior agreement.