GB1271970A - Process operation analysis system - Google Patents

Abstract

1,271,970. Controlling a plurality of processes. WESTINGHOUSE ELECTRIC CORP. 6 Aug., 1969 [22 Aug., 1968], No. 39332/69. Heading B1X. [Also in Division G3] An analysis system for a plurality of process operations comprises control means determining the time interval for which an indication of each operating condition of the process is applied to the analysing means in dependence on the desired analysis. As shown, waste gas from a steel-making or arc furnace process 12 is supplied through a temperature control device 62, responsive to a temperature censor 60, and delivered at a controlled temperature through a filter 36, a flow meter 42, and a pump 38 to a valve 40 which feeds the waste gas to an analyser 78 or an analyser 74 for predetermined interval and at other times discharges to atmosphere through a conduit 70. The signals from the censor 60 and meter 42 are-fed to a programmed control computer 18 which both controls the carrying out of the process 12 and the operation of the temperature control device 62, pump 38 and the valve 40 whereby the waste gas is fed to each analyser 74; 78 for a time interval corresponding to their response time, the transport time of the waste gas being minimised by making the conduit from the valve to the analyser as short as possible. Additional processes, such as 10, are coupled to the analysers through valves, such as 30, the valves being sequentially operated by the computer in accordance with a programme. When one process has terminated its operation the related pump and valve are controlled so that the gas flow is not sampled from that process. The analysers may comprise gas chromatograph, infra-red absorption detectors for analysis of waste gas containing carbon monoxide or carbon dioxide, and electrical conductivity dew-point analysers. It is stated that the same waste gas may flow through both analysers 74, 78 and the computer programmed to ignore the reading of one or other of the analysers.