Patent ID: 6190036
Filing Date: 2001-02-20
Classification: G01N

Abstract:
A method for determining an ice concentration in a main flow of a liquid ice mixture passing through a pipeline, the steps comprising:(a) separating a partial flow from the main flow of the liquid ice mixture passing through the pipeline,(b) providing a first heat exchanger having first and second inlets and first and second outlets,(c) providing first, second, third and fourth temperature sensors at the heat exchanger first inlet, first outlet, second inlet and second outlet respectively,(d) introducing the partial flow into the first heat exchanger through the first inlet,(e) measuring a temperature t.sub.A at the first sensor,(f) heating the partial flow in the first heat exchanger,(g) expelling the partial flow out of the first heat exchanger through the first outlet,(h) measuring a temperature t.sub.B at the second sensor,(i) providing a second heat exchanger having a single inlet and a single outlet,(j) introducing the partial flow into the second heat exchanger through the single inlet,(k) heating the partial flow in the second heat exchanger,(l) expelling the partial flow out of the second heat exchanger through the single outlet,(m) measuring a temperature t.sub.C at the third sensor,(n) re-introducing the partial flow into the first heat exchanger through the second inlet,(o) allowing the partial flow to cool within the first heat exchanger,(p) expelling the partial flow out of the first heat exchanger through the second outlet,(q) measuring a temperature t.sub.D at the fourth sensor,(r) providing a known specific heat capacity cp.sub.fluid and a known enthalpy of fusion h.sub.ice of the liquid ice mixture, and(s) calculating the ice concentration in the liquid ice mixture X.sub.ice according to the equation:X.sub.ice =(t.sub.C -t.sub.D -t.sub.B +t.sub.A) (cp.sub.fluid /h.sub.ice).