Hot curing processes emissions

Hot-box emissions The patterns are generally heated by open air gas burners, producing combustion gas emissions. The off-gas may contain phenol, ammonia, formaldehyde and monoisocyanates (if the resin contains nitrogen) 

Warm-box emissions Compared to the hot-box process, the emissions are significantly lower. The emissions do not contain phenol or ammonia, and also formaldehyde emissions are diminished by a factor of 4. As Ae pattern temperature is also lower compared to the one used for the hot-box process, the woiking conditions are also improved. The environmental impact is considered to be relatively low 

Shell emissions Compared to the hot-box process, cured sand consumption is very low. However, the pre-coated sand contains 2 to 3 times more resin, but as the pattern temperatures are approximately the same, the resulting impact on working conditions is 

Linseed oil emissions As the oils are often in solution in organic solvents such as naphtha or kerosene, a large amount of VOC is generated by curing, which may result in an external odour nuisance. This problem is even more persistent during pouring. These problems, as well as poor productivity, are some of the reasons for the reduction in interest in the use of 

A mass balance for a hot-box core shop is given in Table 3.42. Data were collected from a core shop of a low-pressure die-casting brass foundry [177, Silva Ribeiro, 2002]. 

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