CLIAMS:We Claim:

1. A re-circulating water treatment simulator comprising:

storage and reservoirs;

control system comprising (a) dosing system (b) on-line corrosion analyzer (c ) on-line water quality analyzer cum controller ;

data acquisition & control system,
cooperatively supporting decision over various treatment regime conditions including anyone or more of constitution ,treatment conditions and operating parameters individually and/or in combination.

2. A re-circulating water treatment simulator as claimed in claim 1 wherein
said on-line corrosion analyzer comprises cooperating digital transmitter, power modules and monitoring probes;
said on-line water quality analyzer cum controller comprises (a) dissolved oxygen (DO) indicator cum controller with probe and associated accessories(b) ORP indicator cum controller with probe and associated accessories and (c ) conductivity indicator cum controller with probe and associated accessories.

3. A re-circulating water treatment simulator as claimed in anyone of claims 1 or 2 wherein said control loop and components comprises temperature controller alongwith heating module and flow controller.
4. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 3 wherein said data acquisition and control system comprises i) data acquisition from analyzer cum controllers of water quality parameters; ii) storage of data and creation of user interface with controllers for settling of parametric values and storage intervals; iii) dosing control iv) facilities for monitoring and display of data; v) generation of printed output in tabular and /or graphical form.

5. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 4 wherein said data acquisition and storage system interface with control system preferably for spreadsheet compatible data generation with said display and control system for water quality parameters cooperate with means for display of corrosion rate, pressure and solution temperature.

6. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 5 which is skid mounted and comprises

said storage and reservoirs comprising reservoirs, mixing chamber and stabilization chamber;
said reservoir for storing untreated water;

said mixing chamber connected to said reservoir and receiving water therefrom through a valve such that even when mixing chamber gets filled up, the mixed water do not get mixed with storage water in the reservoir, with provision for optical visualization of upper and lower level of water in the mixing tank and wherein desired water quality parameters can be maintained in mixing chamber through a co-operatively connected control loop such that water enters a stabilization chamber from said mixing chamber through a non return valve and wherein continuous flow is maintained between Stabilization chamber and an experimental spool either through a high temperature , high pressure pump or with a back up facility for operation of the simulator with an additional pump which is able to operate in normal temperature and pressure;

on-line water quality analyzers-cum-controllers adapted to monitor water quality parameters comprising pH, DO, Conductivity, ORP in said experimental spool and based on set parameters through HMI based software , automated control action is initiated such as to activate the dosing system control valves for maintaining the said parameters at desired level; and
said data acquisition, control, storage and retrieval system having interface with control system in such a manner that spreadsheet compatible data is generated and enable display and control facility for water quality parameters along with display of corrosion rate, pressure and solution temperature .

7. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 6, wherein said reservoir is of desired capacity for storing/ mixing the water with chemical inhibitors and having facility for drain line with valve and an overflow line separate from drain line.

8. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 7, wherein said mixing chamber is of desired capacity with stirrer , having ports with suitable lids-one set of ports are for chemical dosing as well as aeration for setting desired parametric values and another set of ports are for insertion of probes of water chemistry analyzers cum controller parameters comprising Dissolved Oxygen (DO), pH, Conductivity, ORP.

9. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 8, wherein said mixing chamber comprises separate overflow line and drain line , air vent, sampling port and facilities for insertion of optional heating element for deaeration.

10. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 9, wherein said stabilization chamber is in the main circulation loop having facility for heating (internal or external) and control of temperature in the stabilization chamber and with provision for a vent.

11. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 10, wherein said experimental/test spool comprises probes inserted for continuous time series data generation at various operating and process conditions and having inlet and outlet valves on spool section, spool by-pass line, facility for insertion of sensors, and facility for automatic dosing of chemicals/inhibitors.

12. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 11 wherein said test spool comprising capped ports capable to withstand high temperature and pressure for :
On-line corrosion analyzer;
pH probe;
DO probe;
Conductivity probe;
ORP probe;
Chemical injection and;
One additional probe;

13. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 12, wherein in said experimental spool section, one main spool is for main line sensors adapted to operate at temperature below 600C, at ambient pressure and the other back up spool on by-pass line is for the temperature above 600C and upto 150C and pressure 10Kg/cm2 such that when the temperature rises above 600C, the spool on which the main sensors are mounted close and the water flows through the other spool where only a corrosion probe is installed which work at higher temperature upto 1500 C, thereby avoiding the required removal of all the water chemistry sensors when the temperature rises above 600C.

14. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 13, wherein said dosing system adapted for dosing Acids/bases/inhibitors in the mixing chamber through solenoid dosing valves actuated/operated based on signals received by way of analyzer set values.

15. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 14, comprising (i) said High pressure High Temperature circulating pump able to sustain temperature upto 1500C and pressure upto 10 kg/cm2 with material of construction of pump head /body coming in contact with water being preferably of SS 316 with integrated facility to control flow rate;
(i) said additional Back up pump to ensure continuous operation able to sustain ambient pressure and temperature upto 600C ;
(ii) a Metering pump for injection of /dosing of the measured amount of chemical inhibitor in either mixing chamber or Experimental spool/stabilization chamber.

16. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 15, comprising temperature controller along with heating module integrated with stabilization chamber and central data management system for maintaining of temperature in the desired experimental range.

17. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 16, comprising flow controller integrated with high temperature High pressure pump for control of water flow with facility for setting of flow rate in at least three different levels.

Dated this the 25th day of February, 2015
Anjan Sen
Of Anjan Sen & Associates
(Applicants Agent)

,TagSPECI:FIELD OF THE INVENTION

The present invention relates to a recirculating water treatment simulator for treatment process control. More particularly, the present invention is directed to provide a system/apparatus for simulating the process parameters and chemical dosing for recirculating water treatment in any industry such as closed loop cooling water treatment in steel industry, including treating and reusing wastewater in the cooling water circuit favouring optimum use of treatment chemicals and online evaluation of treatment effectiveness to maintain water quality parameters at desired level. Importantly, the system/simulator according to the present invention would act as a decision support tool to have control over chemical treatment of recirculating cooling water; i.e, control over inhibitor addition for optimum corrosion protection, comparison between various inhibitors to compare their efficacy, possibility of replacement of costly proprietary inhibitors with generic inhibitors, monitoring of corrosivity and deposition trends under various treatment and process conditions, thus favouring wide scale application and use in various industry.

BACKGROUND OF THE INVENTION

The online monitoring and control of effectiveness of treatment of recirculating water used for various processes in different industry to achieve stipulated water quality parameters in a cost effective yet reliable manner is a long standing requirement. Since iron & steel making involves very high temperature processes, steel industry relies on water as a very critical resource. The useful water in steel industry can be divided into two types – contact water (which is mainly used for surface finishing and pollution control purposes ) and non-contact water ( mainly used for cooling purposes ). While contact water is recycled and/ or discharged to a water body after a series of physico-chemico-biological treatment, closed loop water is continuously recycled, by design, with only a very small percentage discharged as blowdown and replenished through make up water. The challenges of closed loop circuit water management is thus multi-dimensional since it requires taking care of various system stresses arising out of dynamic nature of the processes.

The poor performance of a cooling water system can result in higher operating cost, reduced production, diminished product quality, accelerated depreciation of capital equipment, and in extreme cases total system failure leading to expensive & extensive plant shutdown & maintenance and often safety related incidents. There are three water based areas of concern in closed loop cooling water systems: corrosion of system metallurgy, uncontrolled microbiological contamination and fouling of heat transfer surfaces. Because of their interrelationship they are often referred to as the cooling water triangle. However, all these result either in scale formation or corrosion of the system.

Moreover, the problem gets accentuated since with reduction in availability of makeup water cooling water need to be recycled with higher cycle of concentration. Besides, in order to reduce water consumption per unit of steel produced, there is also an increasing tendency to treat and reuse wastewater in the cooling water circuit.

In order to meet these challenges, a large number of patented chemicals are generally used for cooling water treatment. However, often these chemicals are costly and they are dosed , primarily based on advice of third party ( water treatment chemical companies ) to reduce corrosion, pitting, scale formation, erosion and fouling, in addition to addressing the universal problem of particle settling. However, basis of such recommendation is in the proprietary knowledge domain of third party chemical suppliers. Plant operating personnel have little or no control over it. Since patented chemicals are costly, there is a need to understand their effectiveness vis-à-vis generic chemicals and physical processes in controlling dynamic effect of water quality in cooling water systems.

That is, to elaborate, current water treatment technology and operating practice is in large part based on indirect system performance measures and relies heavily on the interpretation of manual and semi- batch wet chemistry tests by third party vendors with agreement being maintenance of water quality parameters at certain level. Presently there is no methodology through which plant can dynamically monitor treatment effectiveness off-line;

Further, although individual effect of many water quality parameters are available in literature, very little technical information is available in public domain about the combined effect of various ionic, surface & particulate properties & quality parameters of water on system. Since most of the chemicals used are proprietary chemicals, scientific data on their real effect on water quality parameters is also not available in public domain. The effectiveness of proprietary chemicals vis-à-vis generic chemicals is also not well established. Moreover, currently there exists no tool for comparison between various chemicals for their treatment effectiveness. Attaining these multiple goals will be possible when there exists proper understanding of the interrelationship between key water quality parameters, impact of variability of these parameters, in isolation and combination, on particulate, ionic and surface properties of water.

There exists a large number of mathematical model based simulation softwares often called ‘simulators’. However, no physical apparatus for simulation of water treatment have been reported in literature. The main limitation of mathematical model based simulators are :i) they are developed for particular water systems only and ii) predicted errors are often large enough to have any serious practical use.

There has been therefore a persistent need in the related field to provide a system/simulator and method for monitoring and control of recirculating water treatment which would provide a tool for comparison between various chemicals for their treatment effectiveness and online control of process parameters including dosing of chemicals for achieving desired water quality parameters.

OBJECTS OF THE INVENTION

The basic object of the present invention is directed to provide a recirculating water treatment simulator for closed loop cooling water treatment for various industrial processes for determining treatment effectiveness and control process parameters to achieve desired treated water quality parameters.

A further object of the present invention is directed to provide a recirculating water treatment simulator for closed loop cooling water treatment for use in industrial processes wherein the system is able to simulate process conditions to evaluate cooling water treatment effectiveness under dynamic treatment and process conditions.

A still further object of the present invention is directed to provide a recirculating water treatment simulator for closed loop cooling water treatment for use in industrial processes wherein said system/simulator would act as a decision support tool to have control over chemical treatment; i.e, control over inhibitor addition for optimum corrosion protection.

A still further object of the present invention is directed to provide a system for recirculating water treatment simulation for closed loop cooling water treatment for use in industrial processes wherein the system enable comparison between various inhibitors to compare their efficacy and possibility of replacement of costly proprietary inhibitors with generic inhibitors.

Yet another object of the present invention is directed to provide a system for recirculating water treatment simulation for closed loop cooling water treatment for use in industrial processes wherein the system enable online monitoring of corrosivity and deposition trends under various treatment and process conditions.

A further object of the present invention is directed to provide a system for recirculating water treatment simulation for closed loop cooling water treatment for use in industrial processes wherein dosing of treat chemicals will be automatically controlled based on feedback relating to treatment effectiveness and water quality parameters.

A further object of the present invention is directed to provide a system for recirculating water treatment simulation for closed loop cooling water treatment for use in industrial processes wherein the system serves as a tool to help steel plants to shift from third party based system maintenance approach to parameter based approach.

SUMMARY OF THE INVENTION

The basic aspect of the present invention is directed to provide a re-circulating water treatment simulator comprising:

storage and reservoirs;

control system comprising (a) dosing system (b) on-line corrosion analyzer (c ) on-line water quality analyzer cum controller ;

data acquisition & control system,
cooperatively supporting decision over various treatment regime conditions including anyone or more of constitution ,treatment conditions and operating parameters individually and/or in combination.

A further aspect of the present invention is directed to a re-circulating water treatment simulator wherein
said on-line corrosion analyzer comprises cooperating digital transmitter, power modules and monitoring probes;
said on-line water quality analyzer cum controller comprises (a) dissolved oxygen (DO) indicator cum controller with probe and associated accessories(b) ORP indicator cum controller with probe and associated accessories and (c ) conductivity indicator cum controller with probe and associated accessories.

A still further aspect of the present invention is directed to provide a re-circulating water treatment simulator wherein said control loop and components comprises temperature controller along with heating module and flow controller.

A still further aspect of the present invention is directed to provide a re-circulating water treatment simulator wherein said data acquisition and control system comprises i) data acquisition from analyzer cum controllers of water quality parameters; ii) storage of data and creation of user interface with controllers for settling of parametric values and storage intervals; iii) dosing control iv) facilities for monitoring and display of data; v) generation of printed output in tabular and /or graphical form.

A still further aspect of the present invention is directed to provide a re-circulating water treatment simulator wherein said data acquisition and storage system interface with control system preferably for spreadsheet compatible data generation with said display and control system for water quality parameters cooperate with means for display of corrosion rate, pressure and solution temperature.

A still further aspect of the present invention is directed to provide a re-circulating water treatment simulator which is skid mounted and comprises

said storage and reservoirs comprising reservoirs, mixing chamber and stabilization chamber;

said reservoir for storing untreated water;

said mixing chamber connected to said reservoir and receiving water therefrom through a valve such that even when mixing chamber gets filled up, the mixed water do not get mixed with storage water in the reservoir, with provision for optical visualization of upper and lower level of water in the mixing tank and wherein desired water quality parameters can be maintained in mixing chamber through a co-operatively connected control loop such that water enters a stabilization chamber from said mixing chamber through a non return valve and wherein continuous flow is maintained between Stabilization chamber and an experimental spool either through a high temperature , high pressure pump or with a back up facility for operation of the simulator with an additional pump which is able to operate in normal temperature and pressure;

on-line water quality analyzers-cum-controllers adapted to monitor water quality parameters comprising pH, DO, Conductivity, ORP in said experimental spool and based on set parameters through HMI based software , automated control action is initiated such as to activate the dosing system control valves for maintaining the said parameters at desired level; and
said data acquisition, control, storage and retrieval system having interface with control system in such a manner that spreadsheet compatible data is generated and enable display and control facility for water quality parameters alongwith display of corrosion rate, pressure and solution temperature .

Yet another aspect of the present invention is directed to provide a re-circulating water treatment simulator wherein said reservoir is of desired capacity for storing/ mixing the water with chemical inhibitors and having facility for drain line with valve and an overflow line separate from drain line.

A further aspect of the present invention is directed to provide a re-circulating water treatment simulator wherein said mixing chamber is of desired capacity with stirrer , having ports with suitable lids-one set of ports are for chemical dosing as well as aeration for setting desired parametric values and another set of ports are for insertion of probes of water chemistry analyzers cum controller parameters comprising Dissolved Oxygen (DO), pH, Conductivity, ORP.

A still further aspect of the present invention is directed to provide a re-circulating water treatment simulator wherein said mixing chamber comprises separate overflow line and drain line, air vent, sampling port and facilities for insertion of optional heating element for deaeration.

A still further aspect of the present invention is directed to provide a re-circulating water treatment simulator wherein said stabilization chamber is in the main circulation loop having facility for heating (internal or external) and control of temperature in the stabilization chamber and with provision for a vent.

Another aspect of the present invention is directed to provide a re-circulating water treatment simulator wherein said experimental/test spool comprises probes inserted for continuous time series data generation at various operating and process conditions and having inlet and outlet valves on spool section, spool by-pass line, facility for insertion of sensors, and facility for automatic dosing of chemicals/inhibitors.

Yet another aspect of the present invention is directed to provide a re-circulating water treatment simulator wherein said test spool comprising capped ports capable to withstand high temperature and pressure for :
On-line corrosion analyzer;
pH probe;
DO probe;
Conductivity probe;
ORP probe;
Chemical injection and;
One additional probe;

A further aspect of the present invention is directed to provide a re-circulating water treatment simulator wherein in said experimental spool section, one main spool is for main line sensors adapted to operate at temperature below 600C, at ambient pressure and the other back up spool on by-pass line is for the temperature above 600C and upto 1500C and pressure 10Kg/cm2 such that when the temperature rises above 600C, the spool on which the main sensors are mounted close and the water flows through the other spool where only a corrosion probe is installed which work at higher temperature upto 1500 C, thereby avoiding the required removal of all the water chemistry sensors when the temperature rises above 600C.

A still further aspect of the present invention is directed to provide a re-circulating water treatment simulator wherein said dosing system adapted for dosing Acids/bases/inhibitors in the mixing chamber through solenoid dosing valves actuated/operated based on signals received by way of analyzer set values.

A still further aspect of the present invention is directed to provide a re-circulating water treatment simulator comprising (i) said High pressure High Temperature circulating pump able to sustain temperature upto 1500C and pressure upto 10 kg/cm2 with material of construction of pump head /body coming in contact with water being preferably of SS 316 with integrated facility to control flow rate;
(i) said additional Back up pump to ensure continuous operation able to sustain ambient pressure and temperature upto 600C ;
(ii) a Metering pump for injection of /dosing of the measured amount of chemical inhibitor in either mixing chamber or Experimental spool/stabilization chamber.

A still further aspect of the present invention is directed to provide a re-circulating water treatment simulator comprising temperature controller along with heating module integrated with stabilization chamber and central data management system for maintaining of temperature in the desired experimental range.

A still further aspect of the present invention is directed to provide a re-circulating water treatment simulator comprising flow controller integrated with high temperature High pressure pump for control of water flow with facility for setting of flow rate in at least three different levels.

The above and other objects and advantages of the present invention are described hereunder in greater details with reference to the following accompanying non limiting illustrative drawings.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

Figure 1: shows the Flow diagram/Schematic configuration of the system/simulator for recirculating cooling water treatment with control on process parameters to achieve desired water quality parameters according to the present invention showing the various components used in the system.

Figure 2: shows graphically that presence of corrosion inhibitor only marginally suppresses the dissolved oxygen induced corrosion.
Figure 3: shows graphically that chemical inhibitor moderately suppresses pH induced corrosion compared to the standard graph.
Figure 4: shows graphically the effect of temperature on corrosion.
DETAILED DESCRIPTION OF THE INVENTION WITH REFERENCE TO THE ACCOMPANYING DRAWING

The present invention is directed to developing a re-circulating water treatment simulator to study and monitor cooling water treatment effectiveness under dynamic treatment and process conditions. The simulator will be a decision support tool to have control over chemical treatment; i.e, control over inhibitor addition for optimum corrosion protection, comparison between various inhibitors to compare their efficacy, possibility of replacement of costly proprietary inhibitors with generic inhibitors, monitoring of corrosivity and deposition trends under various treatment and process conditions and achieve desired water quality parameters.

Study and monitoring of cooling water treatment is carried out using the present system/simulator involving the following process variables through on-line data generation:
(i) Dissolved oxygen content
(ii) Flow rate/Residence time
(iii) pH
(iv) Conductivity
(v) Total Dissolved Solids
(vi) Oxidation Reduction Potential(ORP)
(vii) Temperature
(viii)Water induced corrosion rate

The simulator data can be integrated with a large number of off-line parameters which can be generated in-situ in simulated sample preparation chamber and therefore can be used with large number of indices like langelier saturation index. Few such important off-line parameters, which by no means exhaustive, are :
(i) Suspended solids content
(ii) Electrokinetic charge
(iii) Water chemistry
(iv) Ionic Concentration

Accompanying Figure 1 shows the Flow diagram/Schematic configuration of the system/simulator for recirculating cooling water treatment with control on process parameters to achieve desired water quality parameters according to the present invention showing the various components used in the system. The system/simulator is operated under normal temperature and pressure using all the probes with temperature going upto 600C during high temperature studies. However, a bypass loop is provided so that studies can be carried out with optional attachment of autoclave, as and when required ( provision for which has been kept in the simulator design ), upto pressure & temperature of 10 kg/cm2 & 1500C respectively with only corrosion probes in the monitoring loop.
Technical details of the system are as follows :
(A) Mounting:

The system is mounted on a skid; The technical and functional purpose that the skid serves are :
i) The skid is able to sustain vertical load of simulator;

ii) The skid is robust enough to sustain the load during Physical Movement;

iii) The Skid is made of non-corrosive material;

(B) Flow Loop and Components

Water from Reservoir is introduced into mixing chamber through a valve. There exists provision for optical visualization of upper and lower level of water in the mixing tank. The desired water quality parameters can be maintained through control loop in mixing chamber. From mixing chamber water enters stabilization chamber through a non return valve. There is continuous flow between Stabilization chamber and experimental spool through a high temperature, high pressure pump. There also exists back up facility for operation of the simulator with an additional pump which is able to operate in normal temperature and pressure. All the components coming in contact with water are made of stainless steel SS 316.

(C) Storage and Reservoirs

There exists One Reservoir of 20 Ltr capacity for storing/ mixing the water with chemical inhibitors; There exists facility for drain line with valve; There exists an overflow line separate from drain line; the reservoir is covered; the reservoir is joined by a ¾ inch dia steel pipe to mixing chamber. Physical arrangement of reservoir and mixing chamber is such that even when mixing chamber gets filled up, the mixed water do not get mixed with storage water in the reservoir. Lids with caps have been provided to reservoir for multiple purposes.

One mixing chamber/tank of 10L capacity with stirrer ; In the mixing chamber there exist ports with suitable lids for chemical dosing as well as aeration; Mixing chamber is connected to reservoir as shown in the diagram ( and as detailed in the reservoir section ) . There exists facility for upper level and lower level of water in mixing chamber. In the mixing tank, there exists two sets of ports. One set of ports are such that it can be used for insertion of probes of water chemistry analyzers cum controller parameters - Dissolved Oxygen (DO), pH, Conductivity, ORP; The other set of ports are used for chemical dosing as well as aeration for setting desired parametric values. In the mixing tank there exists facility for stirring; the stirrer is be made of non-corrosive material with maximum speed of 100 rpm. There exists separate overflow line and drain line in the mixing chamber. The mixing chamber is joined to stabilization chamber through a non-return valve. In the mixing tank there exists air vent, sampling port and facilities for insertion of optional heating element for deaeration .

One Stabilization chamber of 4L capacity
The stabilization chamber is in the circulation loop; Stabilization chamber is connected to mixing chamber through a non-return valve. Stabilization chamber is in the main circulation loop (as detailed in schematic diagram). There exists facility for heating (internal or external) and control of temperature in the Stabilization chamber. There exists facility for a vent in stabilization chamber.

Material of construction of the storage tanks are : Stainless Steel SS 316 . The interconnections are as per schematic diagram in Figure 1.
(D) Pumps
Main pump ( High pressure/High temperarute )

One number High pressure High Temperature(HPHT) Circulating pump is able to sustain Temperature upto 1500C and pressure upto 10 kg/cm2; Material of construction of pump head /body coming in contact with water is : SS 316. This Pump is integrated with facility to control flow rate.

Back up pump : One No. of pump is kept as back up to ensure continuous operation; Back up pump is able to sustain Ambient pressure and temperature upto 600C

Metering pump : For injection of /dosing of the measured amount of Chemical inhibitor in either mixing chamber or Experimental spool/stabilization chamber, there exists a metering pump.

(E) Experimental Spool

Experimental spool is the section in which probes are inserted for continuous time series data generation at various operating and process conditions.
(i) Spool Diameter : 6 inch
(ii) Tubing Length : 2 ft
(iii) MOC of Spool : SS316
(iv)Temperature rating : upto 600C, Ambient pressure ( Main Spool),
(v)Temperature upto 1500C , Pressure : 10 kg/cm2 [ For backup spool];

Test spool have capped ports (able to withstand high temperature and pressure) for :

(i) On-line corrosion analyzer
(ii)pH probe
(iii)DO probe
(iv)Conductivity probe
(v)ORP probe
(vi) Chemical injection
(vii) One additional probe

Inlet and outlet valves on spool section, Spool by-pass line, Facility for insertion of sensors, Facility for automatic dosing of chemicals/inhibitors is shown in the diagram

One spool is for main line sensors which will work at temperature below 600C. The other spool is for the temperature above 600C. When the temperature rises above 600C, the spool on which these sensors are mounted can be closed. Then the water will flow through the other spool where only a Corrosion probe can be installed. Corrosion probe can work at higher temperature upto 1500 C. [ Thus there will not be any need to remove all the water chemistry sensors when the temperature rises above 600C. ]

(F) Valves and Tubings

All necessary valves, tubing and fittings in the loop, coming in contact with water are made of stainless steel; tubings are of ¾ inch diameter.

(G) Dosing System

Dosing System Consists of four Nos. of Dosing Tanks, One small aeration pump, small pipes/tubes, four number of Dosing control valves.

There exists four number of dosing tanks ( 5 L capacity each), SS 316 make; Acids/bases/inhibitors are to be dosed in the mixing chamber through solenoid dosing valves actuated/operated based on signals received by way of analyzer set values.

Dosing System also consist of a small aerator/aeration pump capable of saturating the water with air and thereby increase oxygen saturation.

(H) Online Corrosion Analyzer

On-line corrosion analyzer remains at the heart of simulator. The analyzer set consists of digital transmitter, power modules, requisite software, monitoring probe with carbon steel element.

(I) Online Water Quality Analyzer cum Controllers

On-line Water Quality analyzers-cum-controllers are used to monitor four nos. of water quality parameters and initiate control action ( e.g , actuate dosing valves ) based on set parameters through HMI based software. These analyzers monitor four nos. of water quality parameters ( pH, DO, Conductivity, ORP ), and there exists facility for setting of these parameters through HMI software based on which automated control action can be initiated [ e.g, activate the dosing system for maintaining the parameters at desired level ]

Main modules of this units are as follows:
(i) pH indicator cum controller with probe and associated accessories.
(ii) Dissolved Oxygen (DO) indicator cum controller with probe and associated accessories.
(iii) ORP indicator cum controller with probe and associated accessories.
(v) Conductivity indicator cum controller with probe and associated accessories.

(J) Temperature Controller(alongwith heating module)

Temperature controller along with heating module for maintaining of temperature in the desired experimental range is integrated with stabilization chamber. Temperature controller is integrated with central data management system.

(K) Flow Controller

Flow controller for control of water flow is integrated with high temperature High pressure pump; In the flow controller there exists facility for setting of flow rate in at least three different levels.

(L) Data Acquisition, Control, Storage And Retrieval System

This system consists of the following features:
i) Data acquisition from analyzer cum controllers of water quality parameters (pH, DO, ORP, conductivity );
ii) Storage of data and creation of user interface with controllers for setting of parametric values and storage interval;
iii) Dosing control;
iv) facilities for monitoring and display of data;
v) Generation of printed output in tabular and graphical form.

The data acquisition and storage system have interface with control system in such a manner that spreadsheet compatible data is generated. In addition to display and control facility for water quality parameters there exists facility for display of corrosion rate, pressure and solution temperature .

It is thus apparent that the present system/simulator for monitoring and control of recirculating cooling water treatment parameters provides a tool for physical simulation study of any recirculating cooling water treatment regime; and to study combined effect of various water quality parameters through multi parametric variation. This is required because the same cannot be done on-line and the system/simulator according to the present invention fills the gap.

Results of experimentation using the simulator:
Singular as well as composite effects of major water quality parameters have been studied in detail using the simulator on impact parameter (water induced corrosion rate) in presence as well as in absence of proprietary and generic inhibitors. Within the acceptable range of parameters significant performance gap could not be observed between proprietary inhibition and generic control. Therefore it has been inferred that is possible to replace proprietary treatment with generic treatment; Even if proprietary treatment is not totally done away with, it is possible to move from system performance oriented third party based approach to parameter based approach. Sample results are as follows :

Accompanying Figure 2 shows graphically that presence of corrosion inhibitor only marginally suppresses the dissolved oxygen induced corrosion. Similar results were obtained using all inhibitors.
Accompanying Figure 3 shows graphically that chemical inhibitor moderately suppresses pH induced corrosion compared to the standard graph.
Accompanying Figure 4 shows graphically the effect of temperature on corrosion; while temperature as such may not be responsible for corrosion but acceleration happens due to lower dissolution rate of oxygen at higher temperature.
The water side corrosion rate under multi-parametric variable conditions in absence and in presence of any inhibitor dosage in mild acidic range( 6.0-7.0) are presented in the following Table I and Table II respectively:
Table I: Multi-variable impact in absence of inhibitor
Temp ( in deg C) Mixing DO/Loop DO ( in mg/l) Conductivity ( in µS/cm) Corrosion rate ( mpy)
21-24 2.3-2.5 585-670 1.8-2.3
25-30 4.6-4.8 720-760 3.5-4.7
30-35 5.2-5.4 890-960 3.9-6.5
35-40 6.1-6.4 1020-1130 11.5-21.3
40-45 6.9-7.2 1240-1450 15.8-32.5

Table II: Multi-variable impact in presence of inhibitor
Temp ( in deg C) Mixing DO/Loop DO ( in mg/l) Conductivity ( in µS/cm) Corrosion rate ( mpy)
21-24 2.1-2.3 620-690 1.5-2.1
25-30 3.9-4.6 720-825 2.8-3.6
30-35 4.9--5.1 840-1050 3.6-4.8
35-40 6.0-6.6 1130-1280 9.5-11.9
40-45 6.37-7.4 1350-1640 10.6-13.5

It is thus possible by way of the present invention to provide a system/ simulator to study and monitor recirculating cooling water treatment effectiveness under dynamic treatment and process conditions. The simulator acts as a decision support tool to have control over chemical treatment; i.e, control over inhibitor addition for optimum corrosion protection, comparison between various inhibitors to compare their efficacy, possibility of replacement of costly proprietary inhibitors with generic inhibitors, monitoring of corrosivity and deposition trends under various treatment and process conditions. The simulator facilitate proper understanding of the interrelationship between key water quality parameters, impact of variability of these parameters, in isolation and in combination, on particulate, ionic and surface properties of water, thus favouring wide scale application in a variety of industrial water treatment processes.

We Claim:

1. A re-circulating water treatment simulator comprising:

storage and reservoirs;

control system comprising (a) dosing system (b) on-line corrosion analyzer (c ) on-line water quality analyzer cum controller ;

data acquisition & control system,
cooperatively supporting decision over various treatment regime conditions including anyone or more of constitution ,treatment conditions and operating parameters individually and/or in combination.

2. A re-circulating water treatment simulator as claimed in claim 1 wherein
said on-line corrosion analyzer comprises cooperating digital transmitter, power modules and monitoring probes;
said on-line water quality analyzer cum controller comprises (a) dissolved oxygen (DO) indicator cum controller with probe and associated accessories(b) ORP indicator cum controller with probe and associated accessories and (c ) conductivity indicator cum controller with probe and associated accessories.

3. A re-circulating water treatment simulator as claimed in anyone of claims 1 or 2 wherein said control loop and components comprises temperature controller alongwith heating module and flow controller.
4. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 3 wherein said data acquisition and control system comprises i) data acquisition from analyzer cum controllers of water quality parameters; ii) storage of data and creation of user interface with controllers for settling of parametric values and storage intervals; iii) dosing control iv) facilities for monitoring and display of data; v) generation of printed output in tabular and /or graphical form.

5. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 4 wherein said data acquisition and storage system interface with control system preferably for spreadsheet compatible data generation with said display and control system for water quality parameters cooperate with means for display of corrosion rate, pressure and solution temperature.

6. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 5 which is skid mounted and comprises

said storage and reservoirs comprising reservoirs, mixing chamber and stabilization chamber;
said reservoir for storing untreated water;

said mixing chamber connected to said reservoir and receiving water therefrom through a valve such that even when mixing chamber gets filled up, the mixed water do not get mixed with storage water in the reservoir, with provision for optical visualization of upper and lower level of water in the mixing tank and wherein desired water quality parameters can be maintained in mixing chamber through a co-operatively connected control loop such that water enters a stabilization chamber from said mixing chamber through a non return valve and wherein continuous flow is maintained between Stabilization chamber and an experimental spool either through a high temperature , high pressure pump or with a back up facility for operation of the simulator with an additional pump which is able to operate in normal temperature and pressure;

on-line water quality analyzers-cum-controllers adapted to monitor water quality parameters comprising pH, DO, Conductivity, ORP in said experimental spool and based on set parameters through HMI based software , automated control action is initiated such as to activate the dosing system control valves for maintaining the said parameters at desired level; and
said data acquisition, control, storage and retrieval system having interface with control system in such a manner that spreadsheet compatible data is generated and enable display and control facility for water quality parameters along with display of corrosion rate, pressure and solution temperature .

7. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 6, wherein said reservoir is of desired capacity for storing/ mixing the water with chemical inhibitors and having facility for drain line with valve and an overflow line separate from drain line.

8. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 7, wherein said mixing chamber is of desired capacity with stirrer , having ports with suitable lids-one set of ports are for chemical dosing as well as aeration for setting desired parametric values and another set of ports are for insertion of probes of water chemistry analyzers cum controller parameters comprising Dissolved Oxygen (DO), pH, Conductivity, ORP.

9. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 8, wherein said mixing chamber comprises separate overflow line and drain line , air vent, sampling port and facilities for insertion of optional heating element for deaeration.

10. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 9, wherein said stabilization chamber is in the main circulation loop having facility for heating (internal or external) and control of temperature in the stabilization chamber and with provision for a vent.

11. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 10, wherein said experimental/test spool comprises probes inserted for continuous time series data generation at various operating and process conditions and having inlet and outlet valves on spool section, spool by-pass line, facility for insertion of sensors, and facility for automatic dosing of chemicals/inhibitors.

12. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 11 wherein said test spool comprising capped ports capable to withstand high temperature and pressure for :
On-line corrosion analyzer;
pH probe;
DO probe;
Conductivity probe;
ORP probe;
Chemical injection and;
One additional probe;

13. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 12, wherein in said experimental spool section, one main spool is for main line sensors adapted to operate at temperature below 600C, at ambient pressure and the other back up spool on by-pass line is for the temperature above 600C and upto 150C and pressure 10Kg/cm2 such that when the temperature rises above 600C, the spool on which the main sensors are mounted close and the water flows through the other spool where only a corrosion probe is installed which work at higher temperature upto 1500 C, thereby avoiding the required removal of all the water chemistry sensors when the temperature rises above 600C.

14. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 13, wherein said dosing system adapted for dosing Acids/bases/inhibitors in the mixing chamber through solenoid dosing valves actuated/operated based on signals received by way of analyzer set values.

15. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 14, comprising (i) said High pressure High Temperature circulating pump able to sustain temperature upto 1500C and pressure upto 10 kg/cm2 with material of construction of pump head /body coming in contact with water being preferably of SS 316 with integrated facility to control flow rate;
(i) said additional Back up pump to ensure continuous operation able to sustain ambient pressure and temperature upto 600C ;
(ii) a Metering pump for injection of /dosing of the measured amount of chemical inhibitor in either mixing chamber or Experimental spool/stabilization chamber.

16. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 15, comprising temperature controller along with heating module integrated with stabilization chamber and central data management system for maintaining of temperature in the desired experimental range.

17. A re-circulating water treatment simulator as claimed in anyone of claims 1 to 16, comprising flow controller integrated with high temperature High pressure pump for control of water flow with facility for setting of flow rate in at least three different levels.

Dated this the 25th day of February, 2015
Anjan Sen
Of Anjan Sen & Associates
(Applicants Agent)

ABSTRACT

TITLE: A RECIRCULATING WATER TREATMENT SIMULATOR.

The present invention relates to a recirculating water treatment simulator for simulating the process parameters and chemical dosing for recirculating water treatment in any industry such as closed loop cooling water treatment in steel industry, including treating and reusing wastewater in the cooling water circuit favouring optimum use of treatment chemicals and online evaluation of treatment effectiveness to maintain water quality parameters at desired level. Importantly, the system/simulator according to the present invention would act as a decision support tool to have control over chemical treatment of recirculating cooling water; i.e, control over inhibitor addition for optimum corrosion protection, comparison between various inhibitors to compare their efficacy, possibility of replacement of costly proprietary inhibitors with generic inhibitors, monitoring of corrosivity and deposition trends under various treatment and process conditions, thus favouring wide scale application and use in various industry.
(Figure 1)