Abstract: A method of measuring mass flow rates of liquid phases in a multiphase slug flow containing at least two liquid phases includes (i) passing a flow through a tube; (ii) detecting commencement of passage of a slug in the flow past a first location in the tube; (iii) measuring mass or volume fractions of the liquid phases by transmission of energy through the flow at the first location; (iv) detecting ending of the passage of the slug at the first location; and (v) determining mass flow rate of the liquid phases through the tube from (a) measuring the total mass or volume of liquid flowing through the tube and (b) measuring mass or flow fractions, only between detection of the commencement and the ending of passage of respective slugs in the flow, i.e., only while a slug is present at the measuring point.

Abstract: A method of analysing coal or coke wherein the concentration of ash or mineral matter in coal or coke is determined from (i) the result of a measurement of transmission or scatter of X-rays or .gamma.-rays of a first energy chosen such that there is significant difference in absorption of radiation per unit weight in coal matter and mineral matter excluding iron, combined with (ii) the result of at least one further measurement of transmission or scatter of X-rays or .gamma.-rays at different energy/energies so chosen that there is significant difference in absorption of radiation per unit weight of coal matter and mineral matter and that the relative absorption per unit weights by said coal matter and said mineral matter at any one energy is significantly different from the relative absorption at each other energy including said first energy, and/or (iii) the result of a measurement of iron concentration by neutron capture .gamma.-ray techniques.