Product handling

The first three sections of this chapter discuss the processing and handling of the products of electrolysis. Section 9.1, related to chlorine, comprises most of the chapter. Sections 9.2 and 9.3 then cover hydrogen and caustic soda or potash. Section 9.4 discusses applications of several byproducts that are sometimes found useful. 

Chlorine gas from the electrolyzers is hot and nearly saturated with water. As delivered downstream, it contains various impurities that form in the cells or enter during processing. The major steps in the typical chlorine gas plant, as was shown in Fig. 6.6, are cooling, drying, compression, and liquefaction. The present section covers these steps in turn, as well as the handling of the product and of any chlorine not recovered by Uquefaction. 

The selection of materials of construction is very important in chlorine processing, and the requirements change greatly fix m one section of the process to the next. A chlorine processing plant therefore uses a wide variety of materials. In particular, there is a distinction between dry and wet chlorine. The discussion therefore starts with an overview of this important topic (Section 9.1.2). 

The first step in the gas process is cooling. Direct or indirect exposure to a cooling medium brings the gas to a lower temperature. This incidentally condenses most of the water vapor. The condensate must be treated to remove dissolved chlorine before disposal or return to the electrolysis process. Section 9.1.3 discusses chlorine cooling and condensate handling. 

Even at the lower temperature, the gas is too wet for many applications. In the next step, contact with concentrated sulfuric acid, usually at about 93-98% H2SO4, produces a moisture content below 50 ppm (v/v). The process dilutes the acid to a concentration between 50 and 80%. This spent acid then goes to disposal or reprocessing. A lower spent acid strength reduces the consumption of acid and the amount of spent acid produced, but the final concentration must be suited to the methods used for disposal or recovery. The spent acid, like the condensate removed from the cooling section, contains dissolved 

---

Pre-Production Handling. Salt-cured catde hides, when received at the tannery, are individually bundled to prevent excessive moisture loss. The bundles are tied with ropes that are later cut and removed the hides may be sorted for different weight or quaUty classification at this point. It is best to have hides of similar size and thickness in a given production batch to assure an even reactivity of the processing chemicals and to avoid frequent adjustments in the machinery to compensate for size and thickness variations. In the modem large tannery, the size/quaUty classification is not necessary because the hides arrive in carload quantities under specifications as to size, type, and month of slaughter. 

One of the most vexing aspects of pilot-plant work can be feed and product handling as a pilot plant is neither designed nor operated as a closed-loop system like a commercial plant. Indeed, the problems involved in handling and storing feed and product materials can sometimes seem to rival the pilot-plant process problems in difficulty. 

Storage tanks, lines, and pumps should be heat traced and insulated to enable product handling. Temperature control is required to prevent product degradation because of color alkan olamines have poor heat transfer properties. Exposure to air will also cause product discoloration. Storage tanks should be nitrogen-padded if low color product is required. 

Sodium alum occurs naturally as the mineral mendo2ite. Commercially, it is produced by the addition of a sodium sulfate solution to aluminum sulfate. Small amounts of potassium sulfate, sodium siUcate, and soda ash can be added to improve product handling and performance. After adjustment of the ratio of aluminum sulfate to sodium sulfate, water is evaporated to give a hard cake ia the cooling pans. This cake is further heated ia roasters and ground to a fineness of 99% through a 100-mesh (- 150 fiva) sieve. 

Chlorinated by-products of ethylene oxychlorination typically include 1,1,2-trichloroethane chloral [75-87-6] (trichloroacetaldehyde) trichloroethylene [7901-6]-, 1,1-dichloroethane cis- and /n j -l,2-dichloroethylenes [156-59-2 and 156-60-5]-, 1,1-dichloroethylene [75-35-4] (vinyhdene chloride) 2-chloroethanol [107-07-3]-, ethyl chloride vinyl chloride mono-, di-, tri-, and tetrachloromethanes (methyl chloride [74-87-3], methylene chloride [75-09-2], chloroform, and carbon tetrachloride [56-23-5])-, and higher boiling compounds. The production of these compounds should be minimized to lower raw material costs, lessen the task of EDC purification, prevent fouling in the pyrolysis reactor, and minimize by-product handling and disposal. Of particular concern is chloral, because it polymerizes in the presence of strong acids. Chloral must be removed to prevent the formation of soflds which can foul and clog operating lines and controls (78). 

Maintenance shops—electric, piping, sheet metal, machine, welding. Raw-material and finished-product handling equipment—elevators, hoists. 

Equipment Costs The cost of dehvered equipment forms the basis of most methods of estimating the fixed-capital cost. The equipment required can usually be divided into (1) processing equipment, (2) equipment for handling and storage of raw materials, and (3) finished products handling and storage equipment. 

Are any raw materials or finished products handled at the facility considered hazardous If yes, describe ... 

Is there potential that the product may result m the environmental or non-workplace release of a highly hazardous substance or an environmentally difficult material If yes did the toller receive a life cycle evaluation (for example, disposal of products, handling returns and rejects) Does the Toller understand the information Was written acknowledgment obtained indicating that the information was received ... 

Implied is the availability of Material Safety Data Sheets (MSDS) for all products handled by the toller. The assessor should question the distribution system of product information. 

The release of volatile organic compounds (VOCs) into the air depends on the products handled at the plant. VOCs released may include acetaldehyde, acetone,... 

Fluorides and dust are emitted to the air from the fertilizer plant. All aspects of phosphate rock processing and finished product handling generate dust, from grinders and pulverizers, pneumatic conveyors, and screens. The mixer/reactors and dens produce fumes that contain silicon tetrafluoride and hydrogen fluoride. A sulfuric acid plant has two principal air emissions sulfur dioxide and acid mist. If pyrite ore is roasted, there will also be particulates in air emissions that may contain heavy metals such as cadmium, mercury, and lead. 

Design features for enabling handling of product Handling of electrostatic-sensitive devices Handling hazardous materials Handling fragile materials... 

Do instruct stock keepers on the effects of lost identity, mixing product, handling and packaging methods. 

Pallets are now mostly standardized at 1.2 X 1.0 m and the total weight will be between 4 and 1 t, depending on the product. Handling in small cold stores can be by hand pallet trucks or hand-steered electric drive trucks. These can transport but not lift one pallet onto another. The usual fork-lift truck is a ride-on vehicle, electric driven, and can lift to form a stack of two, three, four or even five pallets high, according to the length of the telescopic lift and the skill of the driver. 

The selection of materials of construction for the equipment and facilities to produce any and all chemicals is a Keystone subject of chemical engineering. The chemical products desired cannot be manufactured without considering the selection of the optimum materials of construction used as the containers for the safe, economical manufacture, and required product quahty, i.e., production, handling, transporting, and storage of the products desired. Therefore, within this Section, the selection of materials of construction [for use within the chemical process industries (CPI), and hy their consumers] is guided by the general subjects addressed herein. 

The packaging costs are those for obtaining disposable containers needed for shipping the product to the customers. (See reference 5 for other details.) For products handled in nondisposable containers no separate packaging cost is listed. 

Goldmann IL, Kader AA and Heintz C. 1999. Influence of production, handling, and storage on phytonutrient content of foods. Nutr Rev 57 46-52. 

Product examinations/investigations, law enforcement authority for, 78 27 Product flammability tests, 7 7 458 459 Product handling... 

The bulk density of the flakes is typically between 250 and 450kg/m3. Compared to pellets, with a typical bulk density of between 750 and 850kg/m3, this has a negative effect on equipment sizing and product handling. Further comminuting the PET flakes increases the bulk density and improves product uniformity, but also creates additional product loss to dust. 

Softening action in doughs, reduce mixing time, increase extensibility, improve texture and grain loaf volume, liberate 6-amylase Increase drying rate of proteins, improve product handling characteristics, production of miso and tofu... 

ISO (International Organization of Standardization) was founded in Geneva in 1947 EN is European Norm DIN (Deutsches Institut far Normung) is an Institute in Germany, which provides standardized industrial production/handling norms BS or BSI (British Standards Institution) is British Standards, produced by the BSI ""... 

---