DD301619A9 - METHOD FOR GENERATING DEFINED CONCENTRATIONS OF CHEMICAL COMBATING MATERIALS OR MATERIAL MIXTURES IN LIQUID FORM IN TRAEGERGASSTROEMES - Google Patents

Abstract

The invention relates to a method for producing defined warfare agent-carrier gas mixtures with the aim of dynamic testing and investigation of materials. The object is achieved in that a warfare agent or a chemical mixture in liquid form introduced via a metering in an injector system with temperature-evaporator with the addition of a carrier gas and the warfare agent or warfare agent carrier gas stream brought into contact with the material to be examined and the concentration curve of Warfare agent is determined. metering; Carrier gas; injector system; Electric motor; Thermostat; Detector; defined concentration; dynamic testing; sorption}

Description

Characteristic of the known technical solutions

Methods are known for the preparation of warfare agent-carrier gas mixtures which are part of adaptive filter testing equipment.

For the preparation of warfare agent-carrier gas Gemischon the so-called Mitführungsverfahren is realized.

Apart from the various modifications of such methods, the concentration is adjusted by means of storage vessels filled with relatively large amounts of warfare agent, the carrier gas flow through or over the warfare agents, built-in harassment to increase the contact area between the liquid and gaseous phase, mixing and calming and defined by admixture unloaded Carrier gas substreams to the carrier gas streams laden with warfare agents.

The following major disadvantages occur:

- High consumption of warfare agent, dddurch conditions that first storage jars must be filled with relatively large quantities of warfare agent and secondly certain warfare agents in the storage vessels due to their sensitivity to hydrolysis in contact with carrier gas streams such. As humid air, are decomposed.

Variations of the experimental parameters (eg humidity, temperature of the carrier gas flows) are due to o. In some cases, warfare agent properties have narrow limits.

Difficulties in generating defined and reproducible warfare agent carrier gas concentrations.

- Insufficient controllability of the process of mixture production.

In addition, permeation cartridges are used with warfare agents in devices for the production of warfare agent-Tiägergas mixtures. In this case, carrier gas streams take up the chemical vapor escaping from permeation cartridges. The permeation devices with warfare agents are of limited use in terms of achieving sufficiently high vapor carrier gas concentrations (e.g., real combat concentrations) and the necessary rate of permeation.

The use of dosing pumps for working with chemical warfare agents is also problematic. The dynamic testing and investigation methods, in which various materials from the generated warfare agent or warfare agent mixture carrier gas mixtures of certain concentrations angströmrömt or flowed through, to perform rtesistenzzeit-, Scrptions-, diffusion and other tests and examinations, consist essentially of the following main procedural steps:

1. Preparation of the warfare agent or warfare agent mixture carrier gas mixture of certain concentration.

2. Temperable device for receiving the material to be tested and examined.

3. Contact of the material in the temperature-controlled device with the warfare agent or warfare agent mixture carrier gas mixtures.

4. Analysis of the emerging from the device for receiving the material to be tested and the material to be tested or warfare agent mixture carrier gas concentrations as a function of time.

All these dynamic methods, apart from the various modifications, have in common that the method steps are separate in terms of apparatus and the process conditions are realized independently. If gas chromatographs are used, they serve, like all other analyzers, exclusively to ensure the method step mentioned under 4.

 This results in the following significant disadvantages:

- High equipment-technical effort

- High effort for detoxification of the equipment used and for measures to protect the operating personnel

- Insufficient controllability of the process steps and their conditions

It is an object of the invention to produce defined concentration of liquid warfare agents or warfare agent mixtures in carrier gas streams for the purpose of dynamic testing of materials with minimal effort and to perform these tests.

Explanation of the invention

It is an object of the invention to provide a method for producing defined warfare agent-carrier gas mixtures. According to the invention, the object is achieved in that a warfare agent or a mixture of explosives introduced in liquid form via a dosing into an injector system with temperature evaporator with the addition of a carrier gas and the warfare agent or warfare agent carrier gas stream of defined concentration brought into contact with the material to be examined and the Residual concentration of the warfare agent is determined.

Auäführungsbeisplel

A Soy-filled microliter syringe - as dosing in the simplest case - is locked with a holding device that allows the mechanical advance of the piston via an electronically controlled electric motor, so that the syringe needle sufficiently deep through a septum into the injector system with temperature-controlled evaporator made of stainless steel enough.

At a set piston advance of δμΙ / h and an air flow through the injector system with a temperature-controlled evaporator of 40 l / h and taking into account the density of 1.013 g / ml, a continuous soman-air concentration of 0.15 mg / l (this corresponds about the concentration of combat) and directed into the thermostat of a gas chromatograph.

The material to be tested or the filled adsorption cartridge to be tested as well as the supply and discharge lines are mounted in the thermostat so that the connection between the sample introduction system and FiD is made. It is a constant adsorption z. B. 303 K set; the FiD detects the breakthrough or increase in the concentration of chemical warfare agents by a continuous increase of the measurement signal.

Claims (1)

A process for the continuous production of defined concentrations of warfare agents or chemical mixtures in liquid form in carrier gas streams for the purpose of dynamically testing materials and their sorptive capacity in a gas stream, characterized in that a warfare agent or warfare agent mixture in liquid form is introduced into an injector system via a dosing body temperature-controlled evaporator with admixture of a carrier gas introduced and the warfare agent or explosive mixture carrier gas stream of defined concentration brought into contact with the material to be examined and the concentration profile of the warfare agent is determined. Field of application of the invention The invention relates to a method for producing defined warfare agent-carrier gas mixtures for the purpose of dynamic testing and testing of materials.