Dosing pump for dosing antiscalant into a membrane-based water treatment system

Abstract

A dosing pump ( 19 ) doses antiscalant into a membrane-based water treatment system ( 1 ). The dosing pump ( 19 ) includes a displacement body for pumping antiscalant into the membrane-based water treatment system ( 1 ) in doses. A motor drives the displacement body. A control module controls the motor. The control module is configured to vary the dosage of antiscalant pumped into the water treatment system ( 1 ) based on a temperature corrected system variable (SVTc) being based on a plurality of operating variables of the water treatment system ( 1 ).

What is claimed is: 
     
         1 . A dosing pump for dosing antiscalant into a membrane-based water treatment system, the dosing pump comprising:
 a displacement body for pumping antiscalant into a membrane-based water treatment system in doses;   a motor for driving the displacement body; and   a control module configured to control the motor and to vary a dosage of antiscalant pumped into the water treatment system based on a temperature corrected system variable based on a plurality of operating variables of the water treatment system.   
     
     
         2 . The dosing pump according to  claim 1 , wherein the control module is configured to receive the temperature corrected system variable or to determine the temperature corrected system variable or to receive the temperature corrected system variable and to determine the temperature corrected system variable. 
     
     
         3 . The dosing pump according to  claim 1 , wherein the plurality of operating variables of the water treatment system comprises at least one operating variable of the group of operating variables consisting of: feed pressure, feed electrical conductivity, feed temperature, feed pH, difference between feed pressure and concentrate pressure, permeate pressure, permeate temperature and permeate electrical conductivity. 
     
     
         4 . The dosing pump according to  claim 1 , wherein the control module is configured to recursively adapt the dosage of antiscalant pumped into the water treatment system based on a previously determined value of the temperature corrected system variable as feedback value. 
     
     
         5 . The dosing pump according to  claim 1 , wherein the control module is configured to adapt the dosage of antiscalant pumped into the water treatment system upon a change of a slope of the temperature corrected system variable. 
     
     
         6 . The dosing pump according to  claim 1 , wherein the temperature corrected system variable is a temperature corrected net driving pressure or a temperature corrected permeate flow or a temperature corrected net driving pressure and a temperature corrected permeate flow or a combination of a temperature corrected net driving pressure and a temperature corrected permeate flow. 
     
     
         7 . The dosing pump according to  claim 6 , wherein the control module is configured to recursively reduce the dosage of antiscalant pumped into the water treatment system as long as the slope of the temperature corrected net driving pressure does not increase or as long as the slope of the temperature corrected permeate flow does not decrease or as long as the slope of the temperature corrected net driving pressure does not increase and as long as the slope of the temperature corrected permeate flow does not decrease. 
     
     
         8 . The dosing pump according to  claim 6 , wherein the control module is configured to increase the dosage of antiscalant pumped into the water treatment system if the slope of the temperature corrected net driving pressure has increased or if the slope of the temperature corrected net permeate flow has decreased or if the slope of the temperature corrected net driving pressure has increased and the slope of the temperature corrected net permeate flow has decreased. 
     
     
         9 . The dosing pump according to  claim 6 , wherein the control module is configured to recursively increase the dosage of antiscalant pumped into the water treatment system as long as the slope of the temperature corrected net driving pressure is above an initial slope or as long as the slope of the temperature corrected permeate flow is below an initial slope or as long as the slope of the temperature corrected net driving pressure is above an initial slope and as long as the slope of the temperature corrected permeate flow is below an initial slope. 
     
     
         10 . A dosing system for dosing antiscalant into a membrane-based water treatment system, the dosing system comprising:
 a dosing pump comprising a displacement body for pumping antiscalant into a membrane-based water treatment system in doses, a motor for driving the displacement body, and a control module configured to control the motor and to vary a dosage of antiscalant pumped into the water treatment system based on a temperature corrected system variable based on a plurality of operating variables of the water treatment system; and   a plurality of sensors for determining the plurality of operating variables of the water treatment system.   
     
     
         11 . The dosing system according to  claim 10 , further comprising a calculation module configured to determine the temperature corrected system variable. 
     
     
         12 . The dosing system according to  claim 11 , wherein the calculation module is configured to receive the plurality of operating variables of the water treatment system from the plurality of sensors. 
     
     
         13 . The dosing system according to  claim 11 , wherein the calculation module is remotely located from the dosing pump and in signal communication with the control module and the plurality of sensors.