AS 4564 pdf download.General-purpose natural gas
For the purpose of this document, the following terms and definitions apply. 3.1 general-purpose natural gas natural gas suitable for transportation in distribution systems and safe for use in natural gas appliances and equipment in Australia Note 1 to entry: Conformance with this standard does not imply that the gas is suitable for transportation in all transmission systems without additional requirements. 3.2 higher heating value gross heating value superior heating value amount of energy, in MJ/m 3 , released when one cubic metre of dry gas at standard conditions is completely burnt in air with the products of combustion brought to standard conditions, with the water produced by combustion condensed to the liquid state 3.3 inert gas material existing predominantly in a gaseous state at standard conditions which does not contribute to the measured heating value of the gas Note 1 to entry: Oxygen is not chemically inert but, as a component of natural gas, it acts to dilute the hydrocarbon content and does not add to the measured heating value. EXAMPLE Carbon dioxide, nitrogen, oxygen and noble gases. 3.4 limit value beyond which the specified characteristic or concentration of the component is not permitted to vary 3.5 lower explosive limit LEL lowest percentage of gas and air in which combustion can be self-sustaining at standard conditions 3.6 maximum allowable operating pressure MAOP maximum pressure at which a pipeline may be operated 3.7 may indicates the existence of an option 3.8 natural gas mixture of gaseous hydrocarbons of the alkane series, primarily methane but possibly also including ethane, propane and higher hydrocarbons in much smaller amounts, used as a fuel. It may also include some inert gases, plus minor amounts of other constituents including odorizing agents3.9 oil mixture of hydrocarbons and other liquids that are non-volatile at atmospheric conditions Note 1 to entry: Oil is likely to consist principally of compressor lubricating and seal oil but can include other liquids such as glycol and heavy components of gas condensates.3.10 relative density specific gravity density of a gas divided by the density of dry air of reference composition at the same specified conditions of pressure and temperature [SOURCE: ISO 6976:2016, 3.4] 3.11 shall indicates that a statement is mandatory 3.12 should indicates a recommendation 3.13 standard conditions temperature of 15 °C and an absolute pressure of 101.325 kPa Note 1 to entry: Standard conditions for natural gas are specified in AS ISO 13443. 3.14 total sulfur sulfur from all sources including odorization of the gas 3.15 Wobbe Index measure of the amount of heat released by a gas burner with a constant orifice.
4.1 Safety The properties of general-purpose natural gas shall be maintained at all times within the limits set out in Table 4.1. 4.2 Odorization Where odorization is required, the odour shall be as specified in Table 4.1. Odorants shall be — (a) suitable for the type of odorizer used; (b) compatible with the gas; and (c) appropriate for the general climatic conditions where the gas is distributed and used. NOTE Odorization may be required by specific jurisdictional legislative requirements. 4.3 Contaminants The gas shall not contain — (a) materials, dust, and other solid or liquid matter, waxes, gums, gum forming constituents, and unsaturated or aromatic hydrocarbons to an extent which might cause damage to, or interfere with, the proper operation of pipes, meters, regulators, control systems, equipment or appliances or which might cause the gas to be harmful or toxic to persons having contact with it in normal work operations or usage; (b) unsaturated or aromatic hydrocarbons to an extent that causes unacceptable sooting; or (c) other substances to the extent that they cause damage to, or problems in operation of, pipelines or appliances or that cause the products of combustion to be toxic, or hazardous to health, other than substances that are usually found in natural gas combustion products.