Waste autoclaving

Both continuous and batch methods may be used in methanolysis. The batch mediod requires an autoclave, crystallizer, and centrifuge and a system for the melting and distillation of the DMT obtained. In the two-stage Hoechst continuous process, waste PET is melted and fed to a reactor. Preheated methanol is added to the autoclave, which is equipped with a mixer. The conversion reaches 70-90% in the first reactor, after which the reaction stream is introduced into a second autoclave at a lower temperature near the bottom, where it rises slowly and die higher density impurities settle at the bottom. The reaction stream leaves the second autoclave and its pressure is reduced to 0.3 MPa. On further reduction of the pressure and cooling, DMT precipitates and is subsequently purified.12... 

Bretsznajder A process for extracting aluminum from clays and a variety of aluminous wastes by continuous digestion with concentrated sulfuric acid in an autoclave. Developed in Poland in the 1980s but not yet commercialized. 

Guillini A process for making gypsum from the waste product from the Wet Process for making phosphoric acid. The waste is heated with water in an autoclave this removes impurities and converts the calcium sulfate dihydrate to the hemi-hydrate. 

The reduction in the numbers of incinerators and the limitations of autoclaves have created the need for alternative medical waste treatment systems. Currently, there are over 40 such technologies available from greater than 70 manufacturers within the United States, Europe, the Middle East, and Australia. While these systems vary in their treatment capacity, the extent of automation, and overall volume reduction, all alternative technologies utilize one or more of the following methods (1) heating the waste to a minimum of 90 to 95°C by means of microwaves, radio waves, hot oil, hot water, steam, or superheated gases (2) exposing the waste to chemicals such as sodium hypochlorite (household bleach) or... 

Minimize the amount of sample and reagents required, since all wastes involving recombinant organisms must be autoclaved. 

Unloading autoclave Room no. Wall, floor, autoclave surface, control panel, movable table, corner Wall, wall near autoclave, doorknob, above autoclave door, floor beneath autoclave, autoclave surface, control panel, each tool, table, chairs, belts of moving benches or chairs, waste containers, corners (especially unused) 1 CFU 3 CFUs... 

McCreadie, H., Jambor, J.L., Blowes, D.W. (1998) Geochemical behavior of autoclave-produced ferric arsenates jarosite in a gold-mine tailings impoundment, in Waste Characterization and Treatment (ed. W., Petruk), Society for Mining, Metallurgy, and Exploration, Littleton, Colorado, pp. 61-78. 

The fissured basalt cores and bentonite were altered by placing them in an autoclave under simulated groundwater at 320°C for 30 and 60 days to simulate 1000 y and 2000 y aging, respectively The waste-form wafers for both experiments were aged in the same manner by treating them for 17 days in saturated steam at 340°C The details of these procedures and the rationale for their use have been published previously (7). The effects of saturated steam on borosilicate glass were discussed in a recent publication (8) ... 

Contaminated cultures which are also radioactive may be autoclaved (dishes should be placed in disposal bags) and then treated as radioactive waste. 

Biohazard handling. All sample handling and disposal procedures should be performed in compliance with the guidelines of the institutional Environmental Health and Safety Office. Gloves should be worn when handling the samples. Discard tips, pipettes, and tubes into a radioactive waste bag, or an autoclavable biohazard bag. 

Fig. 1. Kubitschek style chemostat. A, Air pump B, hosecock clamps (closed during autoclaving) C, growing culture D, air exit port E, ground glass joints F, syringe filter, G, gang valve H, bottle containing water I, input area K, heating tape M, fresh medium O, siphon P, peristaltic pump R, rubber stopper with holes S, splash shield T, silicone rubber tubing W, waste Y, waste collection tube. Circles in the liquids represent bubbles. Stippling indicates media with cells.

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