Urea formaldehyde is the currently state of the art urea granulation additive. Its use is absolutely crucial in order to achieve the required product quality such as crushing strength, bulk density or low caking tendency. Furthermore it is also an inherent granulation aid which ensures a proper performance of the granulation process itself by limiting the generation of dust and providing a high build up rate of the granules. Unfortunately there are also some negative aspects to the use of the pre-condensates of formaldehyde and urea (UF 80, UF85). A major disadvantage is that it still contains a considerable amount of free formaldehyde which is harmful to health. It is categorized as a carcinogenic substance by the IARC (International Agency for Research on Cancer). In addition to that UF solutions contain a certain amount of methanol. Hence, it contributes to a significant part to the VOC emissions from an ammonia/urea complex, which might be requested to be very low by the local authorities. Furthermore urea product treated with formaldehyde cannot be sold as technical grade for most applications. It is not within the specification for the preparation of DEF (Diesel Exhaust Fuel) also known as AdBlue~R. It was UFTs goal in the past years to develop an alternative additive which is capable to guarantee the same product quality as well as at least the same process performance parameters while not contributing to any environmental impact. The result of the development is an alternative additive, which shows a product quality and a granulation performance which is at least as good as the bench mark UF. Different from UF solutions it is not harmful to health or the environment, since it consists of components which are biodegradable and are allowed to come into contact with food. Additionally the application of the alternative additive bears the possibility of utilizing the same urea granules for fertilizer, technical and DEF applications. This extends the range of application of urea ganules and reduces the efforts with regard to logistics for all producers of multiple urea grades drastically.
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