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tem (CCW). The HP Scrubber is equipped with 316 L UG heat exchanger tubes (BC.01 according Stamicarbon Specification A4- 18005). The presence of ammonia in the CCW indicated a leak from tube side (process side) to the shell side (cooling water side). In contrary to the frequent cases of chloride stress corrosion cracks (Cl- SCC) observed in HP Carbamate Condensers, Cl- SCC cracks are seldom observed in HP Scrubbers. The integrity of the said HP Scrubber was compromised, since it was not possible to pinpoint and repair the leak. It was decided by plant management to replace the HP Scrubber as soon as possible. Schoeller Bleckmann Nitec (SBN) in Austria was awarded the contract to supply a new HP Scrubber with a delivery time of only 8 months. Normally a delivery time of 10 to 12 months is anticipated. In order to meet this very short delivery time, SBN and Stamicarbon teamed-up to speed up the engineering and fabrication work. HP Scrubber was transported from Austria to the Middle East by airfreight. In this contribution the difficulty to locate a small leak is described as well as the key issues to manufacture the new HP Scrubber within such short delivery time. 

ondition o Comply with safety and (new) environmental regulations

ise and strength of Stamicarbon technology. 

on or prilling, it needs to be  If the heater is mechanically damaged (leaking tube heat exchanger) also product can contaminate the steam/condensate system and cause corrosion in the carbon steel lines and equipment.

ctions of the reactor CNO (Carseland Nitrogen Operations) believed that there was only 3mm of original material protecting the carbon steel shell. At the end of 1995 Carseland ordered new liner material for the top dome and the cylindrical section approximately 1 m below the head. Carseland consulted Stamicarbon and potential suppliers of liner material and installation expertise. Carseland decided that for reasons of cost and time it was best placing a new liner overtop of the existing liner in the dome.

ss caking, consolidation strength)

ent requirements, but also high standards in respect of its physical properties. This paper will focus on the causes of caking, like formation of crystal bridges serving as contact points between particles and formation of capillary adhesion forming adhesive contacts. Other subjects that will be discussed are: approaches to cake prevention, the action of anti-caking agents, and the methods of applying them. Finally, a new method of rendering prilled urea cake-resistant, based on coating with a novel, high-quality Stamicarbon coating agent named ADVANCE COAT™ Prill Strength, will be introduced. 

has been given to developing and optimizing the synthesis- and recycling-section in the urea plant, that inthe last decade increased attention has been given to developments and optimizations regarding Urea shaping technology (granulation and prilling), whereas over the entire Urea history, also much attention has been given to storage and handling, indicating the importance of product quality, storage and handling. The most important problems occurring in Storage and Handling are directly or indirectly related to (results of) caking, like lump-formation and dusting. Therefore the mechanism of caking of Urea has been made the subject of a paper because we realize that large efforts and considerable amounts of money can be involved with the consequences of caking. In this paper the mechanism of caking via water sorption and desorption is discussed. Especially the caking, spreading through a heap of Urea, observed even in Urea of good quality will be highlighted. This is often caused by moisture migration. The mechanisms of caking are then explained by discussing some examples from practice.

the Americas due to mechanization of agriculture. In order to blend a high quality of granular fertilizer it is very important to produce a stable blend where no segregation of mixture occurs. For good bulk blending quality granules containing nutrients like P, K and/ or S are required. For such granules a premium is paid in the market. In some Asian countries like India bulk blending of fertilizers is not an alternative to compound fertilizer because bulk blending fertilizers is forbidden due to quality control issues in these countries.

who have a thorough knowledge of the dynamic behavior of the process and the spectrum of algorithms which can be implemented in the process control system. The optimization process itself consists of several steps, like setting up a controller performance monitoring system, determining the root cause of poorly performing control loops, fixing potential hardware problems, and tuning the controllers with the proper algorithm and parameters. These well-tuned basic control loops can also act as a solid backbone for model-based advanced process control software like the Stamicarbon EVOLVE OPTIMIZER™, which offers extensive possibilities for stable plant operation and further enhanced economic benefits.

the LAUNCH phase, grass root plants can apply the models to optimize consumption and emission figures.  It allows urea producers to stay competitive with production improvements, monitoring and detection, staff training and full lifecycle support. Further, feedback will be given on the EVOLVE OPTIMIZER™ project at OCI in the Netherlands. This has been in operation since 2012.