diff --git a/opm/simulators/wells/StandardWell.hpp b/opm/simulators/wells/StandardWell.hpp
index 2bccd2058..d80519ef0 100644
--- a/opm/simulators/wells/StandardWell.hpp
+++ b/opm/simulators/wells/StandardWell.hpp
@@ -443,12 +443,6 @@ namespace Opm
                                   const IntensiveQuantities& intQuants,
                                   DeferredLogger& deferred_logger) const;
 
-        std::tuple<Eval,EvalWell>
-        connectionRatezFraction(double& rate,
-                                const double dis_gas_rate,
-                                const std::vector<EvalWell>& cq_s,
-                                const IntensiveQuantities& intQuants) const;
-
         template<class Value>
         void gasOilPerfRateInj(const std::vector<Value>& cq_s,
                                PerforationRates& perf_rates,
diff --git a/opm/simulators/wells/StandardWellConnections.cpp b/opm/simulators/wells/StandardWellConnections.cpp
index 8feff450c..efbecffae 100644
--- a/opm/simulators/wells/StandardWellConnections.cpp
+++ b/opm/simulators/wells/StandardWellConnections.cpp
@@ -639,6 +639,32 @@ connectionRatePolymer(double& rate,
     return {well_.restrictEval(cq_s_poly), cq_s_poly};
 }
 
+template<class FluidSystem, class Indices, class Scalar>
+std::tuple<typename StandardWellConnections<FluidSystem,Indices,Scalar>::Eval,
+           typename StandardWellConnections<FluidSystem,Indices,Scalar>::EvalWell>
+StandardWellConnections<FluidSystem,Indices,Scalar>::
+connectionRatezFraction(double& rate,
+                        const double dis_gas_rate,
+                        const std::vector<EvalWell>& cq_s,
+                        const std::variant<Scalar, std::array<EvalWell,2>>& solventConcentration) const
+{
+    // TODO: the application of well efficiency factor has not been tested with an example yet
+    const unsigned gasCompIdx = Indices::canonicalToActiveComponentIndex(FluidSystem::gasCompIdx);
+    EvalWell cq_s_zfrac_effective = cq_s[gasCompIdx];
+    if (well_.isInjector()) {
+        cq_s_zfrac_effective *= std::get<Scalar>(solventConcentration);
+    } else if (cq_s_zfrac_effective.value() != 0.0) {
+        const double dis_gas_frac = dis_gas_rate / cq_s_zfrac_effective.value();
+        const auto& vol = std::get<std::array<EvalWell,2>>(solventConcentration);
+        cq_s_zfrac_effective *= dis_gas_frac * vol[0] + (1.0 - dis_gas_frac) * vol[1];
+    }
+
+    rate = cq_s_zfrac_effective.value();
+
+    cq_s_zfrac_effective *= well_.wellEfficiencyFactor();
+    return {well_.restrictEval(cq_s_zfrac_effective), cq_s_zfrac_effective};
+}
+
 #define INSTANCE(...) \
 template class StandardWellConnections<BlackOilFluidSystem<double,BlackOilDefaultIndexTraits>, \
                                        __VA_ARGS__,double>;
diff --git a/opm/simulators/wells/StandardWellConnections.hpp b/opm/simulators/wells/StandardWellConnections.hpp
index 515c31758..073e85d13 100644
--- a/opm/simulators/wells/StandardWellConnections.hpp
+++ b/opm/simulators/wells/StandardWellConnections.hpp
@@ -104,6 +104,12 @@ public:
                         const std::variant<Scalar,EvalWell>& oxygenConcentration,
                         const std::variant<Scalar,EvalWell>& ureaConcentration) const;
 
+    std::tuple<Eval,EvalWell>
+    connectionRatezFraction(double& rate,
+                            const double dis_gas_rate,
+                            const std::vector<EvalWell>& cq_s,
+                            const std::variant<Scalar, std::array<EvalWell,2>>& solventConcentration) const;
+
 private:
     void computePressureDelta();
 
diff --git a/opm/simulators/wells/StandardWell_impl.hpp b/opm/simulators/wells/StandardWell_impl.hpp
index 787a8c818..3a252f606 100644
--- a/opm/simulators/wells/StandardWell_impl.hpp
+++ b/opm/simulators/wells/StandardWell_impl.hpp
@@ -558,10 +558,18 @@ namespace Opm
         }
 
         if constexpr (has_zFraction) {
+            std::variant<Scalar,std::array<EvalWell,2>> solventConcentration;
+            if (this->isInjector()) {
+                solventConcentration = this->wsolvent();
+            } else {
+                solventConcentration = std::array{this->extendEval(intQuants.xVolume()),
+                                                  this->extendEval(intQuants.yVolume())};
+            }
             std::tie(connectionRates[perf][Indices::contiZfracEqIdx],
                      cq_s_zfrac_effective) =
-                connectionRatezFraction(perf_data.solvent_rates[perf],
-                                        perf_rates.dis_gas, cq_s, intQuants);
+                this->connections_.connectionRatezFraction(perf_data.solvent_rates[perf],
+                                                           perf_rates.dis_gas, cq_s,
+                                                           solventConcentration);
         }
 
         if constexpr (has_brine) {
@@ -2256,32 +2264,6 @@ namespace Opm
     }
 
 
-    template <typename TypeTag>
-    std::tuple<typename StandardWell<TypeTag>::Eval,
-               typename StandardWell<TypeTag>::EvalWell>
-    StandardWell<TypeTag>::
-    connectionRatezFraction(double& rate,
-                            const double dis_gas_rate,
-                            const std::vector<EvalWell>& cq_s,
-                            const IntensiveQuantities& intQuants) const
-    {
-        // TODO: the application of well efficiency factor has not been tested with an example yet
-        const unsigned gasCompIdx = Indices::canonicalToActiveComponentIndex(FluidSystem::gasCompIdx);
-        EvalWell cq_s_zfrac_effective = cq_s[gasCompIdx];
-        if (this->isInjector()) {
-            cq_s_zfrac_effective *= this->wsolvent();
-        } else if (cq_s_zfrac_effective.value() != 0.0) {
-            const double dis_gas_frac = dis_gas_rate / cq_s_zfrac_effective.value();
-            cq_s_zfrac_effective *= this->extendEval(dis_gas_frac*intQuants.xVolume() + (1.0-dis_gas_frac)*intQuants.yVolume());
-        }
-
-        rate = cq_s_zfrac_effective.value();
-
-        cq_s_zfrac_effective *= this->well_efficiency_factor_;
-        return {Base::restrictEval(cq_s_zfrac_effective), cq_s_zfrac_effective};
-    }
-
-
     template <typename TypeTag>
     template<class Value>
     void