Fining process

Faults in the Glass.—Notwithstanding a]l the precautions that may he taken, air-bubbles frequently remain, and generally exist in great number when the fining process has been obstructed by too great difficulty of fusion in the glass. They aro technically termed seed, blibe, or blister. 

C-E Lummus/Cities Service LC-Fining process licensed by AMOCO (van Driesen and Fornoff, 1985 Beaton et al., 1986) utilizes an expanded-bed reactor. A flow diagram of the LC-Fining process is shown in Fig. 17. The Canadian DOE CANMET process (Menzies et al., 1981), the Exxon M-Coke (Bearden and Aldridge, 1981), and the UOP Aurabon (Anderson et al., 1982) processes now in pilot plant stages of development employ slurry reactors. 

The LC-Fining process is a hydrogenation process capable of desulfurizing, demetallizing, and upgrading a wide spectrum of heavy feedstocks (Tables 9-12 and 9-13) by means of an expanded bed reactor (Fomoff, 1982 Reich et al., 1993 Hydrocarbon Processing, 1998). 

The LC-Fining process has been applied to desulfurization of bitumen extracted from the Athabasca tar sands (Bishop, 1990). In one reported instance, a low-solids bitumen and a high-solids bitumen were employed as feedstocks whereupon good conversion of the bitumen to lower-sulfur products was noted... 

LC-Fining process a hydrogenation process capable of desulfurizing, demetallizing and upgrading heavy feedstocks by means of an expanded bed reactor. 

At this time, the chemistry of the fining process is poorly understood, and hence it is not surprising that this process is often considered as an art rather than a science. For this reason, the fining process sometimes remains inefficient. It is thus our intention here to review the chemistry of fining and present some results of our own investigations. 

ENZYMATIC HYDROLYSIS OF PECTIN. In many factories this fining process is carried out at a juice temperature of 50-55°C. After only a few hours the juice is virtually clear (often completely clear) and can be processed further. 

When this fining process is applied to juices that are not heated, it is usually combined with clarification fining. The enzyme then has a longer time to act, which is needed because of the low temperature. There is no point in using pectolytic enzymes at a juice temperature below 10°C. 

The alteration of flavors of wine observed when colloids were largely eliminated can be explained by the retention of aroma compounds on the macromolecules eliminated by fining processes. On the other hand, the absence of these macromolecules which increase the aroma intensity of some volatile compounds such as ethyl octanoate could incidence general modifications in the flavor equilibrium of wine. 

Figure 9.1. Morphological and immimolristochemical char acteristics of monocytes and macrophages. Panel A demonstrates Wriglrt s stain demonstrating tire classical monocyte kidney-shaped nucleus. Panel B demonstrates tire fine processes on microglial cells called tire fimbriae, hr die brain, microglial cells demonstrate a typical ramified phenotype as shown in panel C. hr neuroinflammatory diseases, such as HAD, cells from die periphery infiltrate die brain as shown in panel D. A blood vessel in brain paienchyma is smiomided by perivascular macrophages.

Smaller gas bubbles also rise and are taken off. High temperatures accelerate the fining process by reducing the viscosity of the melt and increasing the diffusion rate. 

Two moving bed processes are available for license, and include the H-Oil process developed by Hydrocarbon Research Inc. and the LC-Fining process developed by Cities Service and C-E Lummus. 

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