Laboratory and bench scale studies

Catalytic activity was studied in laboratory and bench-scale reactor systems. Laboratory catalytic tests (n-hexane conversion) were carried out in a through-flow reactor under the following conditions T=200-450 °C LHSV=7 h. Bench-scale tests were run in a continuous -flow high-pressure microreactor unit, using diesel oil as a feedstock. Catalysts were reduced and then sulfided at 330 °C for 5 h. The process was studied at T=300-330 °C, LHSV=3 h p=3.5 MPa and H2 CH=500 Nm /m. The criterion for catalyst activity assessment was the freezing point (-20 °C) the measurements were done for the stabilized products. 

The demonstration unit was later transported to the CECOS faciHty at Niagara Falls, New York. In tests performed in 1985, approximately 3400 L of a mixed waste containing 2-chlorophenol [95-57-8] nitrobenzene [98-95-3] and 1,1,2-trichloroethane [79-00-5] were processed over 145 operating hours 2-propanol was used as a supplemental fuel the temperature was maintained at 615 to 635°C. Another 95-h test was conducted on a PCB containing transformer waste. Very high destmction efficiencies were achieved for all compounds studied (17). A later bench-scale study, conducted at Smith Kline and French Laboratories in conjunction with Modar (18), showed that simulated chemical and biological wastes, a fermentation broth, and extreme thermophilic bacteria were all completely destroyed within detection limits. 

Chakrabarti, T. and Subrahmanyam, P.V.R., Biological hydrolysis of urea in a continuous flow stirred tank reactor under laboratory conditions—a bench scale study, Proc. 36th Industrial Waste Conference, Purdue University, pp. 477, 1981. 

The validity of a bench-scale study of fire behavior is dependent on how it translates to the real scale. In general, real scale fires (both laboratory tests and unwanted fires) are poorly defined, and exhibit high sensitivity to a number of uncontrolled variables. 

Dowex XFS-5195.02 was chosen as a representative of the chelating ion exchange resins. Copper, chromium, nickel, and iron were chosen as representative contaminants for laboratory bench-scale studies. 

In order to ascertain whether pyrolysis in the low fractional second contact time range would afford ethylene and co-product yield advantages sufficient to justify still further development of a process, bench scale work was initiated in the Kellogg laboratory in 1965. These bench scale studies provided experimental evidence on the trends of product yields over a contact time range from 0.01 to 0.10 seconds at reaction temperatures from 1400 F (760 0 to over 2000 F (10930c). Investigations were performed on a... 

Bench scale analysis Also known as "bench test . A method of studying different ways of treating wastewater and solids on a small scale in a laboratory. Alken-Murray offers several such test kits including Aiken Clear-Flo Bench Test 1 and Aiken PCB Bench Test. 

This study was run in a laboratory bench-scale unit with 0.75-in. reactor tubes. The catalysts were sized to 10 X 12 mesh and diluted nine-to-one with Si02 in order to spread the reaction out through the bed and to permit measurement of temperature profiles, the profile being an... 

A part of the test plan must include testing for the consequences of equipment malfunction, deviations in process conditions, and human error. Bench-scale equipment, for example, the RC1, is quite suitable for such experiments. By analysis of the process, critical conditions can be defined, which then need to be tested in order to be able to proceed safely from the laboratory to pilot plant studies. In testing abnormal conditions or process deviations, caution is required to assure that no uncontrollable hazard is created in the laboratory. Typical deviations, including impact on the process, are discussed in the following paragraph. 

This chapter focuses on two main subjects. It will first deal with knowledge and methodologies of good practice in the study of chemical and microbial processes in wastewater collection systems. The information on such processes is provided by investigations, measurements and analyses performed at bench, pilot and field scale. Second, it is the objective to establish the theoretical basis for determination of parameters to be used for calibration and validation of sewer process models. These main objectives of the chapter are integrated sampling, pilot-scale and field measurements and laboratory studies and analyses are needed to determine wastewater characteristics, including those kinetic and stoichiometric parameters that are used in models for simulation of the site-specific sewer processes. 

L-Cysteine is a high value a-amino acid used world-wide in a scale of 1200-15001 year-1 as additive in foodstuffs, cosmetics or as intermediate or active agent (as antidote to several snake venoms) in the pharmaceutical industry. Chemical routes generally lack the efficiency of electrochemical techniques, or they produce mixtures of l- and d- forms rather than the L-isomer. The most common electrochemical route is the cathodic reduction of L-Cystine in acid (usually HC1) solution to produce the stable hydrochloride. In Table 10, the charateristic data for a laboratory bench, laboratory pilot and a product pilot reaction using a DEM filter press are compared [13]. A production scale study was carried out in a filterpress reactor divided by a cation exchange membrane with a total area of 10.5 m2. The typical product inventory was 450 kg/24-hour batch time. For more details see Ref. [13]. 

Laboratory-scale test procedures consisting of jar test studies have been used for years, and the test methodology developed is such that full-scale designs can be developed from these studies with a high degree of confidence. A jar test is a series of bench-scale laboratory procedures made on 1- or 2-1 water samples to determine the most effective water treatment method. Tests are performed to identify the most effective coagulants, optimum dosage, optimum pH, and most effective order in which to add various chemicals. 

Pilot-scale treatability studies are enlargements of bench-scale tests, which more closely approach the full-scale project. The objective of pilot-scale tests is to verify treatability outside of a laboratory setting and verify the actual field conditions. Many pilot-scale studies are performed at the actual project site. Data from pilot-scale studies are used to design full-scale field operations. A pilot test may include the following ... 

Gereg and Capolla developed process parameters determined by a model laboratory bench scale Carver press, model C (Carver Inc. Savannah, Georgia, U.S.A.), which were translated to production scale compactor parameters (6). Their study provided a method to predict whether a material is suitable for roller compaction. Their study objectives were to characterize properties of the material to identify process parameters suitable to achieve the necessary particle size and density using the dry granulation process and then translate laboratory information to a production scale roller compactor. Actually, information developed from a Carver press was correlated and scaled-up to a production scale Fitzpatrick roller compactor. Model IR 520 (Fitzpatrick Co., Elmhurst, Illinois, U.S.A.) The compactor produced very similar powder granule characteristics as the Carver press. Various lactose materials, available as lactose monohydrate or spray dried lactose monohydrate, were used as the model compounds. Results indicated that a parametric correlation could be made between the laboratory bench Carver press and the production scale compactor, and that many process parameters can be transferred directly. 

Laboratory Extractors. Pilot-Scale Testing, and Scale-Up. Several laboratory units arc useful in analysis, process control, and process studies. The AKUFVE contactor incorporates a separate mixer and centrifugal separator. It is an efficient instrument for rapid and accurate measurement of partition coefficients, as well as for obtaining reaction kinetic data. Miniature mixer-settler assemblies set up as continuous, bench-scale, multistage, countercurrent, liquid-liquid contactors are particularly useful Tor the preliminary laboratory work associated with flow-sheet development and optimization because these give a known number of theoretical stages. 

The widespread application of herbicides in agriculture has resulted in many polluted surface waters. As a result, numerous pesticides/herbicides have been treated in bench-scale laboratory studies with 03/UV/H202 processes during the last 10 years (see Table 10). Among them, many studies focused on the treatment of atrazine and other. v-triazine herbicides (simazine, prop-azine, etc.). Atrazine is a priority pollutant that similar to other individual pesticides has a very low maximum contaminant level (MCL) (0.1 pg L 1 for the European Environmental Commission according to Directive 80/778/ EEC). In some countries atrazine cannot be used but it is still found in many surface waters. In France, for example, atrazine was banned on September 28, 2001. From applied technologies, only carbon adsorption [180] and possibly advanced oxidations can be recommended to remove some of these... 

Other Cycles Argonne National Laboratory s Chemical Engineering Division is studying other cycles like the copper-chlorine thermochemical cycle. The energy efficiency of the process is projected to be 40 to 45 percent (ANL, 2003). This work is currently being investigated only by ANL, at a bench-scale R D level, and no pilot demonstra-... 

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