Device for analyzing a fluid medium

PCT No. PCT/DK94/00171 Sec. 371 Date Oct. 10, 1995 Sec. 102(e) Date Oct. 10, 1995 PCT Filed Apr. 28, 1994 PCT Pub. No. WO94/25876 PCT Pub. Date Nov. 10, 1994A fully functional analyzing unit is included within the fluid tight housing of a dialyzer which is immersed in the medium to be analyzed. An opening in the housing is closed by a dialysis membrane. A channel defining body cooperates with the membrane to define a flow channel. The unit includes a carrier fluid reservoir and a carrier pump for generating a flow of carrier fluid through the flow channel. By dialysis via the membrane, the flow of carrier fluid is transformed into a flow of sample fluid. A detecting device is coupled to detect an analyte in the sample fluid and for generating a corresponding detection signal. Effluent sample fluid is received in a waste reservoir. The device is suitable for in situ real-time measurement of plant nutrient salts in process waters of waste water treatment plants.