Chlorine Generator Test Apparatus ECE 599, Fall 2011 Vincent Korfhage, Vladimir Chausenko, Sam Ryan, Ryan Ray

Background Information Approximately 1 in 8 people do not have safe drinking water million people die yearly due to water-related diseases. Historically, one of the first chlorine generators was developed and used in Louisville in response to ongoing problems with typhoid death rates. For example, after adding the chlorination system to water in Louisville, the typhoid death rate fell from 52.7/100,000 to 0.9/100,000 in 30 years. There are Non-Governmental Organizations (NGOs) that deliver water purifiers to third world countries, and countries needing disaster relief These water purifiers use chlorination to purify raw water The chlorine destroys bacteria that cause illness These NGOs need low–cost chlorine generators, and they need a capability to test/evaluate commercially available chlorine generators

Chlorination of Water There are two commonly used methods to purify water using Chlorine Electrolysis of NaCl in water to produce Sodium Hypochlorite Electrolysis of NaCl in water to produce Chlorine gas Based on our research, Louisville Water Co. uses the Sodium Hypochlorite technique A solution of NaCl in the water to be treated is electrolyzed into NaClO New Life International, a local NGO, uses a chlorine gas generator Chlorine gas is ”bubbled” into the treated water Testing of treated water is required to make certain that the free chlorine residual is between 0.2 and 0.5 mg/l at the point of use

Project Goals Survey and obtain commercially available chlorine generators Develop a procedure for water purification using the selected chloring generator Develop a test/evaluation capability for the water purification system The test/evaluation system must: allow the end-user to characterize the efficiency of the chlorine generator determine whether the correct amount of chlorine is being generated determine if the chlorine generator is operating adequately to purify the volume of water of interest in a reasonable amount of time operate in remote areas using either battery or solar power

Chlorine Generation Options Chlorine Gas Generator Sodium Hypochlorite Generator Both technologies use aqueous NaCl solutions to make chlorine

Chlorine Gas Generation

Chlorine Gas Generator Operation The membrane passes cations (+) but not anions (-) Therefore Na passes from the anode side to the cathode side The membrane acts as a barrier to mixing, producing sodium hydroxide and a brine solution that contains chlorine gas The chlorine gas evaporates from the brine solution Hydrogen gas is produced in the sodium hydroxide cell The chlorine gas is then collected and used to purify drinking water.

Hypochlorite Generation

Sodium Hypochlorite Generator Operation Water from the reservoir containing salt (NaCl + H2O) enters the cell The hypochlorite generator electrolyzes the NaCl + H2O solution, creating Hypochlorite (NaOCl), which is then pumped into the reservoir Then Sodium Hypochlorite in the reservoir (NaOCL) decomposes back into (NaCl + H2O) Then this solution enters the cell again, fresh hypochlorite is generated

System Requirements Implement a water purifier from commercially available components. Review of journal article This purifier will be used as the test article For a turbidity less than TBD, the hypochlorite concetration should be between 2.5 to 3.8 mg/L at the end of the purification cycle 0.2 mg of hypo per L after 24 hours Les then 0.2 mg repurify Provide a test and characterization capability for the water purification system

Test and Management Requirements Measured Data Turbidity Chlorine concentration Salinity Current and voltage of the generator cells during the purification cycle Temperature of water Management System requirements Graphical user interface System configuration Instrument calibration Data acquisition Time tag and store measured data Provide a report capability that summarizes and displays the test data after each purification cycle

System Diagram – Chlorine Gas

System Diagram – Hypochlorite

Major Components Water Purifier Instrumentation Management Interface Display/Data Management System (DDMS)

Measurements Turbidity Temperature pH: Na, Cl, OH, NaCLO concentrations Current Voltage Cl generated per unit time Hydrogen gas/unit time

Turbidity Turbidity is the cloudiness or haziness of water that is caused by individual particles (suspended solids) that are generally invisible to the naked eye Units of turbidity are NTU It is very important to measure turbidity during water purification processes The amount of hypochlorite/chlorine gas required for safe drinking water changes with different turbidity levels Reference: Sodium Hypochlorite Dosage for Household and Emergency Water Treatment, Daniele Lantagne, AWAA Journal Volume 100:8, pgs ,August, 2008.

Instrumentation-Turbidity Sensor Water sample which was purified by using the chlorine generator that is being tested will be placed into the turbidity sensor We will be using Vernier Turbidity Sensor which can measure from 0 to 200 NTU. 1 NTU is standard for unfiltered drinking water, 0.5 NTU for filtered

Instrumentation-Voltage Probe Voltage probe will be connected to the chlorine generator to measure approximately 12V across electrodes We will be using Vernier 30 Volts Voltage Probe which is able to measure voltages in the range of -30 to 30 Volts

Instrumentation-Current Sensor Current sensor will be connected to the 12VDC battery We will use Vernier High Current Sensor The High Current Sensor has a range of ±10 A

Instrumentation-PH Sensor The PH sensor will be placed into a reservoir with water which was purified by using the chlorine generator that is being tested We will be using Vernier PH sensor

Instrumentation-Temp Probe Temperature sensors will be placed in the reservoir with water We will be using Vernier Stainless Steel Temperature Probe, which has a range of -40 to 273 F

Instrumentation-Salinity Sensor Salinity sensor will be placed in the reservoir with water The Salinity Sensor easily and precisely measures the total dissolved salt content in an aqueous solution We will be using Vernier Salinity sensor This sensor has range of 0 to 50,000 ppm Drinking water salinity should be < 3,000 ppm

Management Interface All sensors will be plugged into an interface card We will be using 2 SensorDAQ USB interface cards, which are made by National Instruments. Turbidity Sensor PH Sensor Salinity Sensor Voltage Probe Current Sensor Temp Probe USB to DDMS

Transition Slide for GUI

Example DDMS Features

Application Development Use Labview to develop an application that: display current level, water temperature, chlorine and salt concentration in water, voltage across electrodes and turbidity of water store the information in a Database for comparison later. shows a pass/fail message for each of the testing parameters and what made it fail Provides an easy to use GUI

Operational Concept - LabVIEW Goal of the LabVIEW program will be to make the program user friendly for untrained personnel. Also easy to evaluate results from the testing apparatus. The LabVIEW program will then display current level, water temperature, chlorine and salt concentration in water, voltage across electrodes, salinity and turbidity of water. LabVIEW will then store the information in an Database for comparison later.

Operational Concept A set of standards is developed to determined the tolerances of the chlorine generation apparatus for current, voltage, pH, salinity, turbidity and temperature. Then LabVIEW compares these values to the values being obtained during the procedure. LabVIEW then will show a pass/fail message for each of the testing parameters and what made it fail.

Current Status Current, Voltage, Temperature, pH, Turbidity and Salinity sensors and Chlorine Cell have been ordered Develop basic operational layout for LabVIEW program Explore test bench layout and how to test our equipment

Questions?