Disclosure to Promote the Right To Information

Transcription

1 इ टरन ट म नक Disclosure to Promote the Right To Information Whereas the Parliament of India has set out to provide a practical regime of right to information for citizens to secure access to information under the control of public authorities, in order to promote transparency and accountability in the working of every public authority, and whereas the attached publication of the Bureau of Indian Standards is of particular interest to the public, particularly disadvantaged communities and those engaged in the pursuit of education and knowledge, the attached public safety standard is made available to promote the timely dissemination of this information in an accurate manner to the public. ज न1 क अ+धक र, ज 1 क अ+धक र Mazdoor Kisan Shakti Sangathan The Right to Information, The Right to Live प0र 1 क छ ड न' 5 तरफ Jawaharlal Nehru Step Out From the Old to the New IS (2004): Methods of test for petroleum and its products, Part 73: Liquifiable Petroleum gases - Detection of hydrogen sulphide - Lead aetate method [PCD 1: Methods of Measurement and Test for Petroleum, Petroleum Products and Lubricants]! न $ एक न' भ रत क +नम-ण Satyanarayan Gangaram Pitroda Invent a New India Using Knowledge! न एक ऐस खज न > ज कभ च0र य नहB ज सकत ह ह Bhartṛhari Nītiśatakam Knowledge is such a treasure which cannot be stolen

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4 IS1448[P:73] :2004 ISO 8819: H al-?ml-$w?mni-%pt- [4t: 73] Efaaa@fam+R7-G@mmmm3mml- ** W-R Indian Standard METHODS OF TEST FOR PETROLEUM AND ITS PRODUCTS [P: 73] LIQUEFIED PETROLEUM GASES DETECTION OF HYDROGEN SULPHIDE LEAD ACETATE METHOD ( First Revision) ICS 91S 2004 BUREAU OF INDIAN STANDARDS MANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG NEW DELHI December 2004 Price Group 2

5 Methods of Measurement and Test for Petroleum, Petroleum Products and Lubricants Sectional Committee, PCD 1 NATIONAL FOREWORD This Indian Standard [ P :73 ] ( First Revision ) which is identical with ISO 8819:1993 Liquefied petroleum gases Detection of hydrogen sulfide Lead acetate method issued by the International Organization for Standardization ( ISO ) was adopted by the Bureau of Indian Standards on the recommendations of the Methods of Measurement and Test for Petroleum, Petroleum Products and Lubricants Sectional Committee and approval of the Petroleum, Coal and Related Products Division Council. This standard was first published in The Committee, therefore, decided to revise this Indian Standard to completely align with ISO 8819: 1993 and publish under the dual numbering system. Accordingly the title of the standard has been modified. The text of ISO Standard has been proposed to be approved as suitable for publication as an Indian Standard without deviations. Certain conventions are, however, not identical to those used in Indian Standards. Attention is particularly drawn to the following: a) Wherever the words International Standard appear referring to this standard, they should be read as Indian Standard. b) Comma (, ) has been used as a decimal marker while in Indian Standards, the current practice is to use a point (. ) as the decimal marker. For tropical countries like India, the standard temperature and the relative humidity shall be taken as 27 * 2 C and 65 * 5 percent respectively. In reporting the results of a test or analysis made in accordance with this standard, if the final value, observed or calculated, is to be rounded off, it shall be done in accordance with IS 2:1960 Rules for rounding off numerical values ( revised).

6 IS 1448 [ P :73 ] :2004 ISO 8819:1993 Indian Standard METHODS OF TEST FOR PETROLEUM AND ITS PRODUCTS [P:73] LIQUEFIED PETROLEUM GASES DETECTION OF HYDROGEN SULPHIDE LEAD ACETATE METHOD ( First Revision) WARNING The use of this International Standard may involve hazardous materials, operations and equipment. This standard does not purport to address all of the safety problems associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use, 1 Scope This International Standard specifies a method for the detection of hydrogen sulfide in liquefied petroleum gases. The lower limit of detectability is 4 mg of hydrogen sulfide in 1 m3 of liquefied petroleum gas. Methyl mercaptan, if present, produces a transitory yellow stain on lead acetate paper which, however, fades completely in less than 5 min. Other sulfur compounds present in liquefied petroleum gas do not interfere with the test. NOTE 1 Liquefied petroleum gases and the products of their combustion should not be unduly corrosive or reactive to materials with which they come into contact. It is therefore important that the presence of any hydrogen sulfide, a highly reactive substance, be detected, Additionally, the odcwr of hydrogen sulfide is unacceptable in some applications of liquefied petroleum gases (e.g. lighter fuel). 2 Principle The vaporized sample is passed over moist lead acetate paper under controlled conditions. Hydrogen sulfide reacts with lead acetate to form lead sulfide and thus produces a coloration on the paper which will vary from yellow to black, depending upon the amount of hydrogen sulfide present. 3 Apparatus 3.1 Apparatus for detecting hydrogen sulfide in liquefied petroleum gas, as shown in figure Lead acetate test paper, either prepared by dipping strips of smooth filter paper into an aqueous 50 g/1 solution of lead acetate, withdrawing the strips and removing excess solution from them with clean filter paper, or commercially available test paper if it is of a type that has been shown to give similar results to paper prepared as above. The strips of the test paper shall be approximately 51 mm long by 9,5 mm wide and have a 3,5 mm diameter hole near to one end. This hole shall permit the strip to hang freely in the test apparatus. 3.3 Flow indicator, comprising a wet test meter or variable area flowmeter, which measures gas flow rates in the range of 2 l/rein to 3 l/rein. 4 Sampling Information on constraints to the use of sample containers and to laboratory testing is given in annex A. 5 Procedure 5.1 Connect the test apparatus (3.1 ) to the sample source with a minimum length of clean stainless steel tubing. NOTE 2 The use of rubber hoses, stoppers, etc., should be avoided since hydrogen sulfide has an affinity for rubber which will result in erroneous test results. Flush the line and apparatus with the sample gas for approximately 1 min. Fill the water reservoir with water at a temperature of 60 C to 80 C. By use of the needle valve, adjust the rate of gas flow to 2,3 l/rein ~ 0,2 l/rein. 1

7 IS 1448 [ P : 73] :2004 ISO 8819:1993 flow Stopper a=to, indicator Glass cylinder, mm, length 203 mm Glass rod _ Lead acetate test paper Stainless steel sample cylinderl) [with provision for suitable ullage) / Watch mmto 038 mm \ wax \,,a,.s 9. Glass tubing ~ K > S+oppe, Pvc tubing._ Stainless steel tubing 1) It is preferable to avoid the use of a sample cylinder by instead using a direct connection to the sample source (see clause 4). Figure 1 Apparatus for detecting hydrogen sulfide in liquefied petroleum gas NOTE 3 Any restriction in the downstream flow indicator, for exactly 2 min to the gas flow maintained at or rapid opening of the needle valve, may result in over- 2,3 l/rein i- 0,2 l/rein. Remove the test paper and pressuring of the glass cylinder. proceed as described in 5.2. Immediately place a single strip of lead acetate paper 5.2 Compare the exposed test paper with a on the hook in the glass cylinder of the apparatus moistened test paper that has not been exposed. (3.1 ) so that the paper, moistened with distilled water, is held midway between the watch glass and the If the distinct coloration is absent, report hydrogen sulfide bottom of the upper stopper. Expose the moist paper negative. 2

8 IS 1448 [P: 731:2004 ISO 8819: If a distinct coloration is present, wait 5 min 6 Test repoti and again compare the exposed test paper with the moistened test paper that has not been exposed and The test report shall record the test result as follows: formation: contain at least the following ins) if the distinct coloration has persisted, report hydrogen sulfide positive; a) sufficient details for complete identification product tested; of the b) if initially there was a distinct yellow coloration that b) a reference to this International Standard; is no longer present after 5 rein, report methyl mercaptan present. c) the result of the test; NOTE 4 In the case of pass-fail data or results from other qualitative tests, no generally accepted method for deter- mining precision is currently available. d) any deviation, by agreement or otherwise, from the procedure specified; e) the date of the test.

9 IS 1448 [ P :73 ] :2004 ISO 8819:1993 Annex A (informative) Use of sample cylinders Because of the chemical activity and physical adsorptive properties of hydrogen sulfide, it is highly desirable to connect the test apparatus directly to the sample source and perform the test on site, rather than transferring sample into a sample cylinder for testing in the laboratory. Experience has demonstrated that the hydrogen sulfide concentration in liquefied petroleum gas samples collected in scrupulously clean sample cylinders is depleted even though the cylinder is made of stainless steel. The exact opposite, an increase in hydrogen sulfide concentration, has been found when samples of liquefied petroleum gas containing no hydrogen sulfide are transferred into sample cylinders that have not been properly cleaned and have been in use with samples containing hydrogen sulfide. This indicates that data obtained on samples tested for hydrogen sulfide in the laboratory are unreliable. 4

10 Bureau of Indian Standards BIS is a statutory institution established under the Bureau of/ndian Standards Act, 1986 to promote harmonious development of the activities of standardization, marking and quality certification of goods and attending to connected matters in the country. Copyright BIS has the copyright of all its publications. No part of these publications may be reproduced in any form without thepriorpermission in writing of BIS. This does not preclude the free use, in the course of implementing the standard, of necessary details, such as symbols and sizes, type or grade designations. Enquiries relating to copyright be addressed to the Director (Publications), BIS. Review of Indian Standards Amendments are issued to standards as the need arises on the basis of comments. Standards are also reviewed periodically; a standard along with amendments is reaffirmed when such review indicates that no changes are needed; if the review indicates that changes are needed, it is taken up for revision. Users of Indian Standards should ascertain that they are in possession of the latest amendments or edition by referring to the latest issue of BIS Catalogue and Standards : Monthly Additions. This Indian Standard has been developed trom Doc : No. PCD 1 ( 1911 ). Amendments Issued Since Publication Amend No. Date of Issue Text Affected Headquarters: BUREAU OF INDIAN STANDARDS Manak Bhavan, 9 Bahadur Shah Zafar Marg, New Delhi Telephones : , , Website : www. bis.org. in Regional Offices : Telephones Central : Manak Bhavan, 9 Bahadur Shah Zafar Marg NEW DELHI { Eastern : Northern : Southern : Western : 1/14 C. 1. T. Scheme Vll M, V. 1. P. ~oad, Kankurgachi KOLKATA SCO , Sector 34-A, CHANDIGARH C. 1. T. Campus, IV Cross Road, CHENNAI Manakalaya, E9 MlDC, Marol, Andheri (East) MUMBAI { { , , { , , { , , Branches: AHMEDABAD. BANGALORE. BHOPAL. BHUBANESHWAR. COIMBATORE. FARIDABAD. GHAZIABAD. GUWAHATI. HYDERABAD. JAIPUR. KANPUR. LUCKNOW. NAGPUR. NALAGARH. PATNA. PUNE. RAJKOT. THIRUVANANTHAPURAM. VISAKHAPATNAM. Printed at New India Printing Press, Khurja, India