Resin plant equipments

An industrial scheduling problem is presented here to illustrate the concepts discussed in this chapter. The industrial problem presented here is from a resin manufacturing plant and it involves optimizing the production schedule in order to enhance the manufacturing process performance. All production in this plant is in batch mode and three kinds of resins are produced. 

The main bottleneck of this plant is the flaker belt. Since there is only one flaker belt, the batch which has come to specifications might be kept inside the reactor depending on the batches competing for the flaker belt. Therefore the major cost associated with flaking is this tied up reactor time. Some of the formulas are less stable than others, therefore hold times for these formulas are minimized and the first priority is given to them. Making solutions takes as much time as flaking but since the resin solutions bypass the flaker belt, they don t have any resource conflicts. 

In this problem the top 10 products which account for 80% of production in the resin plant are considered. 

Our problem consists of two stages in series the reactor and fiaker belt. In the first stage, there are 5 parallel reactors, whereas in the second stage there is only one fiaker belt. Since there is zero intermediate storage between these stages, the resin which is processed must remain in the reactor if the fiaker belt is busy. 

The only difference of our problem from a standard flexible fiowshop scheduling problem is the fact that our reactors in the first stage are not identical. Not aU of the products can be processed in all of the reactors. For example, hydrocarbon resins are only produced in Reactors 5 and 6, which are vertical reactors, whereas rosin resins are only produced in Reactors 1 through 4, which are horizontal reactors. This makes our problem more complex than a standard flexible fiowshop scheduling problem because we also have to consider machine eligibility. 

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All experiments were conducted using normal laboratory glassware. Chemicals used were technical grade chemicals removed directly from process chemical hold tanks where possible resins were from the same production lots as would be placed in the process column equipment. Cation exchange feed rates were the same as obtainable in plant equipment. 

Typical "plant equipment is shown in Fig. 3. The equipment racks are assembled and tested before being installed in hot cells. This rack, which served for some five years, has one high-pressure pump, a short "loading column, two long elution columns, and appropriate associated valves, feed vessels, product collection apparatus, and plumbing. Resin was periodically replaced by hydraulic transfer. 

Today, two industrial methods are applied to meet this target solvent extraction (liquid ion exchange) and ion exchange by resins. Plants using the latter process can be found exclusively in China (smaller works). All others are equipped with liquid ion exchange facilities. 

Boron nitride Phenol-formaldehyde resin chemical equip., corrosion-resistant desalination plants Aluminum... 

The 163 N Building la adjacent to the 183-N Building and houses the demineralisation plant. Here filtered water Is demineralised, degassifled and pumped to the demineralised storage tanks, the building also houses resin regeneration equipment, a control center for the 183-N and 163 N Buildings, plus a water treatment control laboratory. 

Phenolic resins are useful surface coating materials. Resols are useful for stoving lacquers for coating chemical plant, textile equipment, razor blades, brassware cuid food cans. Phenolic resins are used with poly(vinyl formal) as a flexible, tough and solvent-resistant wire enamel. Oil-soluble resins based on synthetic phenols form the basis of some gloss paints. 

When a multiproduct plant is constructed, the amount of each product to be made each year must be included in the scope. This is called the product mix. It is important because the product mix determines the size of much of the equipment. One resin may require a reaction cycle of three hours, while another takes six hours. If the majority of the product is the former resin, a smaller reactor is required than if the majority were the latter. 

The resin supply system should be designed to take advantage of the raw materials in the lowest cost and most effective form. Additives tend to be more expensive than the base resin. Gravimetric rather than volumetric supply of the material is more conducive to minimizing the use of the more expensive feedstock components. The ability of the equipment to utilize reliably 100% of in-plant regrind, additive concentrates, and recycled materials is one of the most important factors to be considered. 

An extrusion trial was performed at the processor s plant using a 38.1 mm diameter production extruder, a proprietary screw design, and resin that had previously exhibited flow surging and reduced rate. The extruder was equipped with three barrel zone heaters with control thermocouples (labeled Tl, T2, and T3) and two pressure sensors. One pressure sensor was located in the midsection (zone 2) of the barrel (P2) and the other at the end of the barrel near the tip of the screw (P3). Both transducers were positioned over the top of the screw such that a pressure variation due to screw rotation would be observed. 

The PET and aluminum chips require further drying so that they can be electrostatically separated. This is the most expensive part of the entire process. "The aluminum cap is only 1% by weight of the bottle," explains Dittman, "but the equipment to remove it represents about 30% of the investment in the plant. It s out of balance, and we are trying to remove the aluminum more cheaply." The process-which at the CPRR plant can handle about 600 lb per hour, or a potential capacity of about 5 million lb per year—generates clean, well-separated (99.9%) granulated plastic chips that can be sold to a manufacturer who uses the resins. 

From adsorption analysis data, it is possible to calculate theoretical yields of deoiled wax, asphalt, resins, and solvent extraction yields of waxy raffinate. Nearly 100 different stocks have been so evaluated by California Research Corp. during the past few years and many of these data have been correlated with operations in refinery equipment and with pilot plant operations. 

The frequency of decompositions depends on the process, whether the plant is equipped with a tubular reactor, a multi-chamber autoclave, or single autoclaves. Important factors are the pressure, temperature, and residence time in the reactor and in the high-pressure separator. The frequency of decompositions is also influenced by the raw materials and the resins which are manufactured. Last, but not least, the frequency of decompositions depends on the shape of the plant, on the training of the operators, and on the know-how of the company or the assistance of the licensor. 

Multipurpose plants are equipped with a two-step separation system, to enrich the resin and the essential oil fraction. Plants which process highly viscous, sticky extracts (such as pepper), are provided with two separators switched in parallel for the first separation step. 

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