Lattice Intellectual Property Limited

British Gas Plc

Bg Corporation

Bg Intellectual Property Ltd.

Robert Richard Thurston

Paul Stephen Hammond

Barry Leonard Price

Paul S Hammond

Geoffrey John Parkinson

Paul Steven Hammond

A method and apparatus for measuring the relative density of a gas. The apparatus includes a chamber to which a gas in question, for example natural gas, is supplied through an inlet and leaves through an outlet. The speed of sound SoS at ambient temperature is measured using any suitable method such as electronic control and a calculating device and an ultra-sound emitter and an ultra-sound receiver. The ambient temperature T is observed by a temperature sensor, and a thermal conductivity sensor measures the thermal conductivity of the gas at two different temperatures above the ambient temperature. One value ThC of the thermal conductivity is measured at 70&deg; C. above ambient and the other value ThC of the thermal conductivity is measured at 50&deg; C. above ambient. The control calculates the relative density RD of the gas according to the formula RD&equals;g&middot;ThC &plus;h&middot;ThC &plus;i&middot;SoS&plus;j&middot;T &plus;k&middot;.T &plus;l where (g, h, i, j, k and l) are constants.

Method and apparatus for measuring the relative density of a gas

An energy meter which measures a volume of gas supplied, which measures a calorific value of the gas supplied, and which calculates an energy value corresponding to the measured volume of gas supplied and the calorific value. The structure to measure the volume of the gas supplied and to calculate the energy value may be provided in a single unit. The structure to measure the calorific value of the gas supplied preferably includes a structure to measure the speed of sound in the gas and further preferably measures a first thermal conductivity of the gas at a first temperature and measures a second thermal conductivity of the gas at a second temperature which differs from the first temperature, and is arranged to produce the calorific value of the gas corresponding to the measured speed of sound in the first and second thermal conductivities.

Measuring energy consumption

Measuring relative density of a gas

Method and apparatus for measuring the calorific value of a gas

Apparatus for measuring a gas value

Apparatus to measure the calorific value and/or the Wobbe index of fuel gas supplied along a pipe. A control can operate two outlet valves and cause an inlet valve to be locked in a closed position or be unlocked to stay in a normally open state until the gas pressure in a chamber of predetermined volume reaches a preset pressure difference above the pressure in the pipe. Under direction of the control, a pump moves fuel gas from the pipe into the chamber whilst the outlet valves are closed. Once the pressure in the chamber attains the preset difference, the inlet valve closes automatically to be held locked closed by the control. Certain properties of the gas in the chamber, such as thermal conductivity, specific heat capacity and speed of sound, are measured and corrected to STP conditions. The pump moves two samples of gas into the chamber at two sequential times, each time until the gas pressure therein attains the preset value and the inlet valve again closes automatically in a locked position. Then 1 of 2 outlet valves is opened to allow gas from the chamber to discharge to the pipe through either an orifice place or a capillary passage. This discharge allows the control to measure the gas density or viscosity at STP, from which the calorific value and/or the Wobbe index of the gas is/are determined.

Measurement of a gas characteristic

Growing community of inventors

Melbourne, United Kingdom

Robert Richard Thurston