Orsat Apparatus Pdf Download _BEST

An Orsat gas analyser or Orsat apparatus is a piece of laboratory equipment used to analyse a gas sample (typically fossil fuel flue gas) for its oxygen, carbon monoxide and carbon dioxide content. Although largely replaced by instrumental techniques, the Orsat remains a reliable method of measurement and is relatively simple to use.[1]

The apparatus consists of an intake valve which feeds into a calibrated water or glycerin jacketed gas burette, this burette is then connected by tubing to two or more absorption pipettes containing chemical solutions that absorb the gases it is being used to measure. The intake and each of the absorption pipettes are valved with stopcocks to allow the movement of gas through the apparatus to be precisely controlled. For safety and portability, the apparatus is usually encased in a wooden box with a handle.

Orsat Apparatus Pdf Download

DOWNLOAD 🔥 https://urluss.com/2y3DaK 🔥

The base of the gas burette is connected to a leveling bottle which typically contains slightly acidulated water with a trace of chemical indicator (typically methyl orange) for colouration. The small amount of acid added to the water reduces the solubility of carbon dioxide. The leveling bottle can be lifted and lowered to enable readings to be taken at constant pressure and to transfer the gas to and from the pipettes containing the different absorption media. The movement of gas through the apparatus is entirely controlled using the leveling bottle and the various stopcocks.

Sample gas is contacted successively by a series of chemically reactive solutions. Each solution removes a specific constituent of the sample gas mixture with the corresponding decrease in gas volume at each step representative of the volume of the specific gas removed. A levelling bulb is used to adjust all gas volume measurements to atmospheric pressure. Ordinarily, the analysis is applied in the field using the portable, orsat apparatus to determine the volume composition of carbon monoxide, carbon dioxide, oxygen, and unsaturated hydrocarbons in the gaseous emission from combustion processes. Results are usually expressed in volume percent of each component gas. Methane and ethane shall be determined by fractional combustion and nitrogen is calculated by difference.

The apparatus shall consist of the conventional orsat type in which volumes are made comparable by pressure temperature compensator, with a manometer interposed between the compensating tube and burette.

The portable orsat apparatus is fitted with a metal or wooden carrying case and uses a shortened form of burette with three gas absorbing pipettes. In order, starting from the burette, the pipettes are filled with potassium hydroxide, pyrogallol and cuprous chloride solution respectively. After filling the above pipettes to the engraved mark with the above solutions and before starting the test adjust the level of each to atmospheric pressure using the levelling bulb. Open the stopcock of the burette to the atmosphere. Raise the levelling bulb until the burette fills to the stopcock with salt water (saturated). Connect the stopcock of the burette to the atmosphere to be sampled or to a sample container and fill the burette with sample gas by lowering the levelling bulb until the meniscus of the water level reads the desired volume in the burette (V1). Open the stopcock connecting the burette to manifold of the absorbing system and also open the stopcock of the potassium hydroxide pipette. Pass the gas contained in the burette into the potassium hydroxid pipette by first raising and then lowering the levelling bottle. Repeat until three to five full contacts have been made. Return the remainder of the gas sample to the burette using the levelling bulb-until the level of potassium hydroxide solution returns to the engraved mark, and with the pipette stopcock closed, again, adjust the water level in the burette to atmospheric pressure using the levelling bulb. Measure the volume V2 of the remaining gas and record the percent carbon dioxide as follows:

In the laboratory bench apparatus the burette is filled with mercury and enclosed in a water jacket. The pipettes are connected to the burette by a manifold and a bubbling pipette containing sulphuric acid (4.4.3.2) is used together with a slow combustion pipette (4.4.3.4) which is equipped with a separate levelling bulb. Pipettes (4.4.3.5 and 4.4.3.6) are added to the system. Results of both absorption and combustion analyses are reported.

monoxide and specific hydrocarbon gases as the application of the method dictates to prepare synthetic mixtures for admission into the apparatus as calibration gas. Such calibration gases may be standardized if desired by gas chromatography and/or gravimetric methods.

Any commercial gas Chromatograph equipped with dual column fittings, a four channel thermal conductivity detector and both a six port gas sampling valve and a syringe injection port, may be adopted to this analysis. Commercially available models designed specifically for this analysis are recommended. A schematic diagram of one such apparatus is given in Fig. 2.

30 METHODS OF SAMPLING AND ANALYZING MINE GASES

in a row, all being connected to a manifold through which communica-

tion with the burette can be made by merely opening a stopcock. In

the combustion analysis the entire residue that has been unabsorbed

by the various reagents is burned in a suitable pipette in the presence

of an excess of air or oxygen 5 and the percentage of methane calcu-

lated on the basis of the contraction in volume produced by burning

and the amount of carbon dioxide formed.

The nitrogen which is unabsorbed by ordinary gas-analysis proce-

dures and is incombustible is determined by subtracting from 100 the

sum of the percentage of all other gases found. This is usually ex-

pressed as percentage of nitrogen (N2) and contains about 1 per cent

of argon, which, however, has physical and chemical properties

similar to nitrogen and for practical purposes may be considered

as such.

TYPES AND LIMITATIONS OF GAS APPARATUS USED BY THE

BUREAU OF MINES FOR MINE-GAS ANALYSIS

The three types of apparatus used by the bureau for complete

analysis of mine atmospheres are the Haldane,6 the laboratory Orsat,7

and the portable Orsat.8

HALDANE APPARATUS

The Haldane apparatus is designed for the analysis of air contam-

inated with small amounts of carbon dioxide, methane, carbon mon-

oxide, hydrogen, and nitrogen and deficient in oxygen. All of

these constituents in a gas mixture can be determined (by complete

analysis), or the procedure may be modified to include one or more

as desired. If, for example, only the methane content is needed, the

procedure is much shorter, and far less time is required than when a

complete analysis is made. The collector of samples should always

advise the laboratory as to the analysis desired.

Samples to be analyzed by the Haldane apparatus must not con-

tain an explosive mixture of combustible gases (methane, hydrogen,

and carbon monoxide). Also, they must contain enough oxygen to

burn completely all of the combustible gases, because no means for

adding oxygen for combustion or for handling explosive mixtures are

provided, as with the Orsat types. Therefore, the collector is re-

p This applies to the type of apparatus for mine-fire gases described in these instructions. With the

laboratory type of Orsat, described in Bull. 197, Bureau of Mines, Sampling and Examination of Mine

Gases and Natural Gas, by G. A. Burrell and F. M. Seibert, revised by G. W. Jones, 1926, 108 pp; or Tech.

Paper 320, The Bureau of Mines Orsat Apparatus for Gas Analysis, by A. C. Fieldner, G. W. Jones, and

W. L. Holbrook, 1925, 18 pp., the CO and1H2 are determined by passing the gas slowly through copper oxide

heated to 300 C., which oxidizes the CO to CO2 and the H2 to HO. The residue which contains the

methane is burned afterwards by slow combustion with oxygen.

6 Burrell, A. G., and Seibert, F. M., Sampling and Examination of Mine Gases and Natural Gas; Bull.

197, Bureau of Mines, revised by G. W. Jones, 1926, 108 pp.

? See Fieldner, A. C., Jones, G. W., and Holbrook, W. L., The Bureau of Mines Orsat Apparatus for

Gas Analysis, Tech. Paper 320, Bureau of Mines, 1925, 18 pp. See also footnote 6.

* See footnote 6,

Louis Hengist Orsat was born 14/8/1837 in Paris. His father was a chemical manufacturer, and made blanc de cruse (PbCO3.Pb(OH)2) at Clichy. Louis entered the cole Polytechnique, graduating in 1855. He became an engineer working on his own account, and became involved in steam raising and engines. He became aware of the efficiency implications of the fuel/air ratio, excess air resulting in waste of heat in hot exhaust gases, and excess fuel resulting in formation of carbon monoxide, with loss of the fuel's potential heat. He developed the apparatus now known as the Orsat Apparatus for analysing exhaust gases. He obtained a British Patent (No. 1853) on 22/5/1873.

He gave a long description of its application to optimisation of energy efficiency in the Annales des Mines (1875, 8, pp 485-506). His list of applications included furnaces, gasifiers, locomotives, blastfurnaces, reverberatory furnaces, lead chamber gases, CO2 generators, as well as respirable air. He went on to give case studies of several of these, including a long series of tests on locomotives in motion, on various French railways. The key attributes of the apparatus were its simplicity of operation "by an intelligent worker", and its compactness and portability, allowing it to be operated on a running locomotive footplate.

A funny thing: it was a lot more difficult than usual to find out about this guy. There were Wikipedia articles on the apparatus (needless to say, not very good) in English, German, Greek and Polish. On Orsat himself, nothing. And nothing in French!. Who would have thought it possible? I might just write a dummy French Wikipedia article suggesting (in view of his odd second name) that he was English. See if anyone bites (Note 1). 2351a5e196