Process and apparatus for testing fluids for fouling

Abstract

There is disclosed a novel mobile apparatus and process therefor including a heat transfer test assembly and related conduit and valve assemblies for connection in fluid flow communication to a heat transfer apparatus for in-situ testing of the fluid passing therethrough and including monitoring and recording apparatus. The heat transfer test assembly includes a heating member for controlled heat input and thermocouples to measure the surface temperature of heating member to permit fouling determinations at varying flow rates with simultaneous monitoring and recording thereof together with data, such as corrosion, pH, conductivity, and the like.

Description

FIELD OF THE INVENTION

The present invention relates to a process and apparatus for testing fluids, and more particularly, to a process and apparatus for the in-situ testing and simultaneously monitoring and recording of aqueous and non-aqueous fluid systems for fouling tendencies, and parameters, such as conductivity, pH, turbidity, corrosion and the like.

BACKGROUND OF THE INVENTION

The chemical water treatment industry has historically been involved with reducing or inhibiting the inherent scale forming or fouling tendencies of natural waters associated with large industrial cooling water systems. Many of the foulant components found in water systems originate with the incoming supply, but some contaminants enter the system from the local environment or from process contamination.

Fouling is an extremely complex phenomenon. From a fundamental point of view, it may be characterized as a combined momentum, heat and mass transfer problem. In many instances, chemical reaction kinetics is involved, as well as solubility characteristics of salts in water and corrosion technology. It has been stated that if the fouling tendency of a cooling water and (shown as 86 in FIG. 3) generate signals representative of a temperature transmitted via leads 120 to a reference junction 122 for transmission via leads 124 to the analog-digital converter 94.

The transducers 78 receive signals generated by the flow meters 32 and 34 and in turn transmits a signal via leads 126 and/or lead 128 to differential pressure cell 80 which generates an analog signal representative of flow rate transmitted by lead 130 to the analog-digital converter 94.

The flow cell 76 including a plurality of probes are connected by leads 132, 134 and 136 to a conductivity monitor 138, a pH monitor 140 and a corrosion monitor 142, respectively, connected to the analog-digital converter 94 by leads 144, 146 and 148, respectively. As known to one skilled in the art, the analog-digital converter transforms analog information into digital output data, which in turn is transmitted by lead 150 to the computer printout assembly 152 96 for recording in a referenced time frame.

In operation, the monitoring and recording assembly 90 disposed in a suitable support assembly and enclosed in a self-contained environmental container is caused to be positioned adjacent a unit operation or process, such as a heat exchanger or delignification digester, respectively, employing a fluid to be tested, inter alia, for fouling tendencies to permit evaluation and/or facile treatment to remedy such fouling tendencies. A source of power is connected to the power inlet assembly 92 and a flexible conduit placed in fluid flow communication with the unit operation or process, generally on the up-stream side thereof. The circulating fluid is caused to flow via conduit 40 into the piping assembly 30 via either flow meter 33 or 34 by control of valves 46 or 48, respectively, and thence sequentially through the rotameter 36 via conduit 50 under the control of valve 52, through the heat transfer test assembly 10 via conduits 54 and 56, through the flow rate control valve 38 via conduit 62 and conduit 64 under control of valve 66 and finally through the flow cell 76 via conduit 70 to be discharged through outlet 68 to waste or to be returned to the unit operation or process.

During such operational time period, power is supplied by leads 116 to the heater element 18 of the tube member 16 with the temperature of the wall of the heating member 14 being monitored to obtain an average temperature thereof. Simultaneously, the bulk fluid temperature is monitored by thermocouple 86 together with the monitoring of the fluid velocity to determine what, if any, velocity effects there are on fouling under given operating conditions. Water velocity is controlled by the constant flow valve 38 and is visually monitored by the rotameter 36 concomitant with electronic monitoring by the differential pressure cell 80 sensing the pressure drop across either flow meter 32 or 34.

The wall thermocouples 26, the bulk water temperature thermocouple 84, the wattmeter transducer 114 and differential pressure cell 80 are connected to the analog-converter 94 via reference junctions 122 to convert analog electrical signals to digital output signals which are transmitted for recordation to the computer printer 96, it being understood that the computer printer is capable of effecting some computation to generate calculated data, such as a fouling factor. Such fouling factor is time related to data from the conductivity monitor 138, the pH monitor 140 and the corrosion monitor 142. In this manner, various data is simultaneously collected of factors relating to fouling, etc. with corrective anti-foulant action taken if dictated by the recorded data.

After recording the aforementioned data, the monitoring and recording assembly 90 is disconnected from the unit operation or process by closing valves 46 or 48 and disconnecting inlet 40 from the fluid source. Thereafter, the monitoring and recording assembly 90 may be facilely moved to another location within the plant or to another plant site.

While the process and apparatus of the present invention has been described generally in the context of an aqueous heat transfer fluid circulating through a heat exchanger, it will be understood that the process and apparatus is applicable to any heat transfer fluid including hydrocarbons, euthetic salt solutions and the like, circulating through a vessel in heat transfer relationship where fouling is a problem. Additionally, provisions for the measurements of parameters other than corrosion, pH and conductivity, such as cation concentrations, etc. may be readily provided for in the monitoring and recording assembly.

While the present invention has been described in connection with an exemplary embodiment thereof, it will be understood that many modifications will be apparent to those of ordinary skill in the art; and that this application is intended to cover any adaptations or variations thereof. Therefore, it is manifestly intended that this invention be only limited by the claims and the equivalents thereof.

Claims

1. An apparatus for testing a fluid to monitor and record fouling data together with other parameters which comprises:

a piping assembly including a fluid inlet and outlet means and a heat transfer test assembly, said heat transfer test assembly including a heating member including with a heating element disposed within a conduit means having a passageway for said fluid;

means for measuring temperature of said fluid entering said heat transfer test assembly;

means for supplying electrical energy of a preselect quantity to said heating element;

means for measuring a wall temperature of said heating element;

flow means for measuring velocity of said fluid through said conduit means;

means for measuring a parameter selected from the group consisting of parameters of said fluid comprising corrosion, pH and conductivity; and

means for simultaneously recording said preselect quantity of electrical energy to said heating element, said measured temperature of said fluid, said measured wall temperature of said heating member, said measured velocity of said fluid through said piping assembly and said measured parameter parameters.

2. The apparatus as defined in claim 1 and further comprising a flow control valve connected in said piping assembly.

3. The apparatus as defined in claim 2 wherein said flow control valve is of a constant flow type including a pressure equalizer.

4. The apparatus as defined in claim 1 wherein said flow means includes a venturi device.

5. The apparatus as defined in claim 4 wherein said venturi device is connected to a differential pressure cell to generate a signal responsive to a pressure drop across said venturi device.

6. The apparatus for testing a fluid as defined in claim 1 and further including two flow means of differing rated flow rates.

7. The apparatus as defined in claim 1 and further including converter means to convert analog electric signals to digital output signals coupled to said means for simultaneous recording.

8. The apparatus as defined in claim 7 and additionally comprising means to calculate a fouling factor from said fouling data comprising said measured fluid temperature, preselect quantity of electrical energy, measured wall temperature and velocity of said fluid.

9. The apparatus as defined in claim 1 wherein said apparatus is supported on a movable structure within a chamber having environmental regulating capabilities.

10. The apparatus as defined in claim 9 wherein said movable structure is a van.

11. The apparatus as defined in claim 1 and further comprising means to disable said means for supplying electrical energy at a preselect elevated temperature condition.

12. A process for testing a fluid to be passed through a unit in an indirect heat transfer relationship to monitor and record fouling data and other parameters which comprises:

(a) connecting said unit in fluid flow communication with a test zone of a mobile assembly said test zone including a heating member having a source of heat;

(b) measuring temperature of said fluid;

(c) energizing said source of heat;

(d) measuring temperature of said heating member during passage of said fluid through said test zone;

(e) measuring flow rate of said fluid;

(f) monitoring and measuring a parameter parameters of said fluid selected from the group consisting of comprising corrosion, pH and conductivity; and

(g) simultaneously recording the data of steps (b), (d), (e) and (f).

13. The process as defined in claim 12 wherein said flow rate is measured by a differential pressure across a venturi zone.

14. The process as defined in claim 12 wherein said flow rate of said fluid is varied through said test zone.

15. The process as defined in claim 12 where said data is also recorded in a manner for further electronic transmissions to a data bank for such unit.

16. The process as defined in claim 12 wherein said unit is on stream.

17. The process as defined in claim 16 wherein said fluid after passage through said test zone is returned to said unit.

18. The process as defined in claim 12 wherein said measurements are analog signals which are converted to digital signals prior to step (g).