IN order to determine the future prediction of increasing atmospheric

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1 Instrumentation In Environmental Research Projects: Open Top Chamber (OTC) and Free Air CO 2 enrichment (FACE) Mr. Nikam Prashant, Dr. R. H. Chile and Dr. S. B. Pal Department of Instrumentation Engineering, S.G.G.S. Institute of Engineering and Technology, Nanded Dr. Pal Founder and Director of Genesis technologies, Kalyan (M.S.) (prashantnikam31@gmail.com) 1 Abstract The exponentially rising of temperature in environment is major problem now a days. Due to these the concentration of CO 2 also get change which effectively influence the productivity of various agricultural crops, Innovative approaches for conducting long-term experiment on plant have been developed to investigate the growth and yield response of different plants to predicted elevated level of CO 2. Accuracy of result depends on the system adapted and its maintenance of the desired level of CO 2 with natural conditions for other parameters. For that fully automated system is developed, therefore this system help to Agricultural Research Scientist to do there research work by knowing what would be the plant condition after 25yr/50yr. They studied each and every change in plant and tree due to changes in environmental condition in controlled environment. Now a days there are some new system like Open Top Chamber (OTC), Free Air CO 2 Enrichment (FACE) with controlled environment. The parameter are control based on requirement of Scientist, parameter are to be monitor Humidity, Temperature, CO 2, Intensity of light, Moisture, Wind speed, Wind direction etc. and Controlling of Temperature, CO 2, Humidity etc. Whole system is Automatically monitor and control through Supervisory Control and Data Acquisition (SCADA) and different Hardware Supporting controller like Data Logger / Programmable Logic Controller (PLC). Keywords Open Top Chamber (OTC), Free Air CO 2 Enrichment (FACE), Data Logger, SCADA development. I. INTRODUCTION IN order to determine the future prediction of increasing atmospheric CO 2 concentration on vegetation, experimental plant have been exposed controlled CO 2 concentration in Open Top chambers and in open field using recently developed Free Air CO 2 Enrichment Technology (FACE). The plant inside Open Top Chambers approaches that of the field outside but generally it is warmer,more humid and alter air movement. Due to such environmental condition created causes plan to grow differently than outside. Moreover there is significant 100 % better growth inside. Experiment carried out in both OTC and FACE are showed that relative growth responses P. P. Nikam and Dr. R. H. Chile are with the Department of Instrumentation Engineering, S.G.G.S. Institute of Engineering and Technology, Nanded, MH India. and Dr. S. B. Pal is Founder and Director of Genesis Technologies,Kalyan (M.S.) (prashantnikam31@gmail.com). to elevated CO 2 not significantly different between OTCs and FACE, but some plant condition suit in OTCs and some plant condition suit in FACE. In ICRISAT institute experiment carried out in both OTC as well FACE. Advantage of FACE technology is that in open field condition no one can controlled concentration CO 2 with any degree of precision, but FACE approaches overcome this problem. In present the increasing CO 2 concentration in atmosphere has led to major research efforts to determine what effects it will have on the vegetation of the earth in the future. This research generally involved exposing plants to elevated or controlled level of CO 2 for various lengths of time and observe plant responses. The main objective of instrumentation in environmental research is that scientist get controlled environmental condition and carried their research suitably. Both these technique introducing technical development that is adapting DATA LOGGER / PLC and SCADA software in order to maintain CO 2 concentration in respective condition and automatically study response of plant to elevated level of CO 2 or any other gas of interest. A. Design of Open Top Chamber Structural design of Open Top Chamber (OTC) The OTC structure is of square type, having dimensions. The structure OTC is fabricated by Galvanized Iron (GI) pipe and installed in experimental field. The OTC is covered with Polyvinyl chloride (PVC) sheet of 120 micron gauge having more than 90% of transmission of light. At some height of each chamber frustum with angle 1 m inside, was reduce dilution effect of air within the chamber. The upper portion of OTC is kept open so that to maintain natural condition of temperature and humidity. Because due to PVC sheet temperature inside OTC is always 4-5 degree greater than ambient temperature. Sensor mounting in OTC In each chamber of OTC fitted with portable temperature and humidity sensor and portable CO 2 monitor device to get data in control room through four core shielded cable. Also we can see data in chamber itself.

2 2 CO 2 Supply to OTC and Air sampling The plenum at the base of OTC chamber provided for proper circulation of CO 2.The 100 percent CO 2 gas of commercial grade is used to elevated CO 2 level within the chambers. Three CO 2 gas cylinder of 47 kg capacity of each is used separately to each chambers. The CO 2 gas is released to each chamber through manifold fitted with PU tubing. The solenoid valve is used to regulate the flow of CO 2 in each chamber, used separately to each chambers and place in CO 2 cylinder storage room. 120 lit. capacity of air compressor is used to pump air mixed with CO 2 into each chambers through PU tubing. The uniformity of CO 2 is maintained by pumping CO 2 gas diluted with air by air compressor. Now for proper controlling of CO 2 purpose air is sample by portable monitor and give signal in the form of 4-20 ma to control room. CO 2 control and Monitoring system The equipment for monitoring and controlling CO 2 in OTCs is fully automatic and desired level of CO 2 is maintained throughout the experimental period in OTC with the help of system. Data logger, SCADA software and PC is used to monitor and control appropriate CO 2 level in each chamber. The SCADA software facilitates to set different concentration of CO 2 in different OTC chamber at a time. Signal obtain from portable CO 2 monitor i.e ma signal process toward data logger, using data logger and SCADA software signal is compare with actual set value of CO 2 level in ppm for particular chamber then control signal is given to solenoid valve of particular chamber to close or open CO 2 supply to chamber thereby regulate desired level of CO 2.this process is continue to all OTCs to maintain desired level of CO 2 in ppm. Also SCADA software facility to continuously records and displays actual data of each chambers. Fig. 1. Block Diagram OTC Flow-chart of Controlling CO 2 in Open Top Chamber B. Design of Free Air CO 2 Enrichment (FACE) Structural Design of Free Air CO 2 Enrichment (FACE) Structure of FACE system are of two types one is horizontal for small plants and another one is vertical for tall trees. We are using Vertical hexagonal type structure which is made up of GI pipe. Dimension of structure 15 ft of height and 10 m of diameter. On each arm of FACE ring facility of at interval of 5 ft manual operated valve to operate FACE ring at height

3 3 Fig. 2. Flow-chart of controlling CO 2 in OTC Fig. 3. Block diagram of FACE System of 5 ft, 10 ft and 15 ft. Also on each arm there are no. of unique design of CO 2 releasing nozzle to covered maximum distance of FACE ring. 3 point of CO 2 pump PU tube is place at different location in FACE ring to pull the sample of air and transmitted in control room. To measure CO 2 concentration in air sample using CO 2 analyzer. Sensor Mounting In FACE Ring FACE ring facilities temperature and humidity sensor, portable CO 2 monitor, wind speed, wind direction and photosynthetic active radiation (PAR) light intensity sensor. Signal is obtained from these sensor transmitted toward control room through four core shielded cable. CO 2 Supply To FACE Ring and Air Sampling Circular GI pipe line is provided under soil to get CO 2 in each arm. This CO 2 is circulated in FACE ring to elevate CO 2 level in ppm. Six CO 2 cylinder of 47 kg of each capacity is provided to each arm through manifold which is place in CO 2 cylinder storage room with GI pipeline. Six solenoid valve is used for each arm of FACE ring and one valve is for main CO 2 line, therefore total seven solenoid valve used to control FACE ring. 300 lit capacity of air compressor is used to pump air mixed with CO 2 into FACE ring through GI pipe. The uniformity of CO 2 is maintained by pumping CO 2 gas diluted with air by air compressor. CO 2 Control and Monitoring System The equipment for monitoring and controlling CO 2 in FACE ring is fully automatic and desired level of CO 2 is maintained throughout the experimental period in FACE ring with the help of system. The system basically consist of CO 2 analyzer to measure CO 2 coming from field, motor/ aspirator to pump sample from field FACE ring, solenoid valves to regulate CO 2 in ppm, Air flow meter, air filter, CO 2 gas cylinder for supply of CO 2 gas, air compressor to maintain the uniformity of CO 2 gas at desired set point, anemometer is use to measure wind speed and direction, relay card is used to operate 230 v operated solenoid valve, relay module is use as output of data logger, data logger, SCADA software and pc. CO 2 analyzer: CO 2 analyzer is main instrument in FACE system. This is non-dispersive Infrared (NDIR) gas analyzer, which is microprocessor based system with single beam optical system. CO 2 gas analyzer model ZRJ/ZRE type is used to measure concentration CO 2 of air pull from field area of FACE ring. Before direct inter into gas analyzer motor is fitted with analyzer. In order to safety of CO 2 analyzer from excess moisture in the air set of desiccant glass column of self-indicating coarse silica gel (filter) is fitted before sample air enter into CO 2 gas analyzer as precautionary measure. Another filter is used to direct drain out water molecule. Also after motor flow rotameter is used to regulate flow of air. The CO 2 gas analyzer is auto-calibrated, hence no need to calibrate manually. Output of gas analyzer is 4-20 ma signal is given to one of the channel of data logger through isolator whose input is 4-20 ma signal. Fig. 4. CO 2 analyzer use in FACE system The SCADA software facilitates to set different concentration of CO 2 in FACE ring. Signal obtain from CO 2 gas analyzer i.e ma signal process toward data logger, using data logger and SCADA software signal is compare with set value of CO 2 level in ppm and wind speed signal is compare with set value so that both are form NOR gate then control signal is given to solenoid valve through relay card to particular

4 4 arm of FACE ring to close or open CO 2 supply to arm of FACE ring thereby regulate desired level of CO 2. This process is continue to maintain desired level of CO 2 in ppm. Also SCADA software facility to continuously records and displays actual data of FACE ring. Flow-chart of controlling CO 2 in FACE Ring Fig. 7. Data Logger Configuration for FACE DATA LOGGER CONFIGURATION FOR FREE AIR CO 2 ENRICHMENT SCADA DEVELOPMENT FOR OPEN TOP CHAMBER (OTC) AND FREE AIR ENRICHMENT (FACE) Fig. 5. flow-chart of CO 2 controlling in FACE Ring II. DATA LOGGER CONFIGURATION AND SCADA DEVELOPMENT DATA LOGGER CONFIGURATION FOR OPEN TOP CHAMBER Fig. 8. Flow-chart for SCADA Development Fig. 6. Data Logger Configuration for OTC

5 5 FLOW-CHART OF GATE BUILDER IN SCADA FOR OTC AND FACE ALGORITHM FOR CODE BUILDER IN SCADA Step 1 Initialize the parameter (i, rl2,str1,ing1) Step 2 Enter the while loop if it satisfied the condition, else go to step 6. Step 3 Call the numeric value from each channel (8) of 3 data logger. Step 4 Store numeric value in string gate and display it on template. Step 5 - Acquired numeric value and check it for sensor break, over range, under range, faulty channel conditions according display on screen. Step 6 go to step 2. Step 7 end. III. RESULTS Data report of Open Top Chamber Fig. 10. Data report of OTC Data report of Free Air CO 2 Enrichment Fig. 9. flow-chart of Gate Builder in SCADA Fig. 11. Data report of FACE

6 6 IV. CONCLUSION We have designed and developed the fully automated control system for sensing, monitoring and controlling system in global environmental research project. Experiment on plant is long term process to get result. The Open Top chamber (OTC) and Free Air CO 2 Enrichment (FACE) systems give fully controlled elevated CO 2 level environment so that scientist do their research with more precisely. Providing controlled CO 2 environment using data logger and Supervisory control and data acquisition system and other Instrumentation technology in field of environmental science may led to global climate change research. ACKNOWLEDGMENT This Project is sponsor by Genesis Technologies organization which developed projects for govt. research institute. Also Project Free Air CO 2 Enrichment (FACE) system is Indias 1st vertical release FACE system. This project was developed at International Crops Research Institute for Semi- Arid Tropics (ICRISAT) Hyderabad. We are thank full to the Institute. REFERENCES [1] M.Vanjara, M.Mahesvari, P.Ratnakumar, and Y. S. Ramakrishna, Monitoring and controlling of co2 concentration in open top chamber for better understanding of plant responses to elevated co2 level, Indian Journal of Radio and space physics, vol. 35, [2] M. V. Oijen, A. H. C. M. Schapendonk, M. J. H. Jansen, C. S. Pot, and R. Maciorowski, Do open top chambers overestimate the effect of rising co 2 on plants? an analysis using spring wheat, Global change Biology, vol. 5, pp , [3] D. C. Uprety, S. C. Garg, B. S. Bisht, and H. K. Maini, Co2 enrichment technologies for plant responses studies, Journal of Scientific and Industrial Research, vol. 65, pp , [4] E. S. Bernhardt, J. J. barber, J. S. Pippen, L. Taneva, J. A. Andrews, and W.H.Schlesinger, Longterm effect of free air co2 enrichment on soil respiration, Biogeochemistry, vol. 7, pp , [5] G. R. Hendrey, D. S. Ellsworth, K. F.Lewin, and J. nagy, A free air enrichment system for exposing tall forest vegetation to elevated atmospheric co 2, Global change Biology, vol. 5, pp , [6] B. A. Kimball, P. J. Pinter, G. W. Wall, R. L. Garcia, and R. L. Morte, Comparison of responses of vegetation to elevated co2 in free air and open top chambers facilities, Advances in Carbon Dioxide Effects Research ASA special publication no.61, 2002.