Liquid wastes Laboratory

Much of the experience and data from wastewater treatment has been gained from municipal treatment plants. Industrial liquid wastes are similar to wastewater but differ in significant ways. Thus, typical design parameters and standards developed for municipal wastewater operations must not be blindly utilized for industrial wastewater. It is best to run laboratory and small pilot tests with the specific industrial wastewater as part of the design process. It is most important to understand the temporal variations in industrial wastewater strength, flow, and waste components and their effect on the performance of various treatment processes. Industry personnel in an effort to reduce cost often neglect laboratory and pilot studies and depend on waste characteristics from similar plants. This strategy often results in failure, delay, and increased costs. Careful studies on the actual waste at a plant site cannot be overemphasized. 

A third source of aquatic plutonium is liquid effluent discharged from laboratory operations into ponds and streams. An example of this is a former waste pond at Oak Ridge National Laboratory, Pond 3513, that received liquid wastes with low concentrations of transuranic elements before it was retired. This impoundment has water quality similar to high pH natural ponds. 

Quartz (Si02) and other silicates are generally stable in acidic solutions but will dissolve in highly alkaline waste solutions, decreasing the pH of the waste. The process by which this reaction occurs is complicated because it creates complex mixtures of nonionic and ionic species of silica. Scrivner and colleagues39 discuss these reactions in some detail. They observe that the silicates in solution buffer the liquid. Also, laboratory experiments in which alkaline wastes have been mixed... 

Under joint sponsorship by the U. S. Army Research, Development and Engineering Center (ARDEC) and the U. S. Department of Energy (DOE), a bench-scale transpiring wall reactor was developed by Sandia National Laboratories, FWDC, and GenCorp Aerojet. The reactor, which uses SCWO, was designed to treat military and other liquid wastes. A commercial application of the technology is in use to destroy munitions, colored smokes, and dyes. SWCO may also provide a viable alternative to incineration for the destruction of chemical weapons. 

It was observed that EDAR index values and intervals (Tables 2 and 4) did not change markedly with the deletion of two toxicity tests. Results of applying the EDAR index to waste samples indicate that values and ranks relate to the solubility of toxicants in aqueous phases. Based on this evaluation, wastes from photographic and X-Ray laboratories were observed to be extremely hazardous in contrast to hydrocarbon-containing waste leachates, described as either slightly hazardous or hazardous. The existence of sub-levels for an equivalent hazard description allows for better sample discrimination (e.g., Pharmaceutical solid waste leachate versus liquid waste with pesticides in Table 5). 

Army. 1983b. Tertiary treatment of effluent from Holston AAP industrial liquid waste treatment facility III. Ultraviolet radiation and ozone studies TNT, RDX, HMX, TAX, and SEX. Frederick, MD U.S. Army Medical Bioengineering Research and Development Laboratory, Fort Detrick. Document no. AD A137672. 

Type C laboratories can be fitted out in normal chemical laboratories. The floors, walls and benches should be free of grooves, and the ventilation should be good. It is recommended that all operations with radionuclides be carried out in tubs and that suitable containers be provided for solid and liquid waste. Because of the risk of incorporation, all mouth operations (e.g. pipetting with the mouth) are strongly forbidden. For wiping of pipettes and other equipment, paper tissue is used. Monitors must be available at the working place, to detect radioactive substances on the equipment and to check hands and working clothes for radioactivity. 

The IRC has diversified its program by introducing new categories of samples (waters from various origins, sediments, fish, seaweed, liquid waste, cereals, and soil, etc.) in which laboratories involved in environmental monitoring of nuclear power plants are interested. 

RIA techniques generate great amounts of radioactive liquid wastes whose composition depends on the specific assays that are carried out in each laboratory. Liquid wastes from RIA techniques are usually composed of different types of proteins (some of them radioactively labelled), preservative solutions, several low-molecular-weight organic compounds, and inorganic salts— all in aqueous solutions. These wastes are classified as low and medium radioactive, but they are also potentially infectious since they can contain pathogens from patient s blood [4]. Sometimes, the infectious risks of these wastes can be much more dangerous than the risks associated with radioactivity. 

Figm-e 32.7 shows the scheme of the solution proposed by the authors for treating radioactive liquid wastes from RIA laboratories. Since part of the radioisotope is in ionic form [5], reverse osmosis can be used for radioisotope removal. But before the application of reverse osmosis, a pretreatment is required. It consists of the following two stages ... 

Waste Disposal In laboratories two types of wastes (i.e. liquid and solid) are often encountered. Arrangements have to be made for disposal of these wastes. For disposal of liquid wastes use of lead pipes or earthen ware pipes is considered most suitable. However care be taken to avoid the flow of solids like pieces of filter paper, cork, broken glass pieces etc. through these pipes, otherwise these pipes get chocked. For disposal of such solid wastes metal boxes or wooden boxes be provided. Such boxes be placed in the comers of the laboratory and students be asked to put all solid wastes in these boxes. Such waste boxes can even be placed under the sinks as shown in Fig. 

Hanford in the first decade of operation (B5). As a result of their pile accident, the Chalk River plant disposed of over a million gallons of liquid waste containing 104 curies of long-lived fission products to the ground (M3). At Oak Ridge, thousands of curies of fission products have been disposed of in open waste pits (S2). The specific experiences at these locations, however, cannot be applied to other locations without field and laboratory evaluation of local problems. 

Fresquez PR, Foxx TS, Naranjo L. 1996a. Uptake of strontium by Chamisa (Chrysothamnus nauseosus) shrub plants growing over a former liquid waste disposal site at Los Alamos National Laboratory Proceedings of the HSRCAVERC joint conference on the environment. Los Alamos, NM ... 

Fresquez, P.R., Foxx, T.S. and Naranjo, L. (1995). Strontium concentrations in chamisa (Chrysothamnus nauseousus) shrub plants growing in a former liquid waste disposal area in Bayo Canyon. Los Alamos National Laboratory report LA-13050-MS. 

Regardless of the chosen method, all employees must adhere to government regulations and site-specific license requirements. Because of the acids and solvents used in many laboratories, some liquid waste streams should be collected separately to avoid exothermic reactions that may lead to explosions. 

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