Remotely Monitoring Gas Flow in a BioDigester


4-Channel Compact Data Logger w/ GPRS modem



CHESTERLAND OH — Recently  Next  Industries  supplied  the  datalogging  solution for a  wastewater treatment company  looking to  optimize  its operation.  In the natural gas industry, it's a well-established technique  to  produce  biogas  by  aerobic  or  anaerobic "digestion,"  starting  from  various  biodegradable  materials. The gas obtained this way consists of  60-70% methane, and can  be  used  to  fuel  the  digester's  boiler  and  electric generator engines.



The  plant's  Utilities  Director  decided  that  the  ideal  way  to incrase yields was to  monitor and record the bio-digster's gas flow.  For  example,  immediately  after  feeding  the  digester there is usually a  strong  momentary  increase in gas production, but there are  also seasonal  variations since  cold  temperatures  inhibit  production.  Consequently,  controlling  the  feed  rate  will  improve  the production process. The director also requires the capability to send alarms by SMS messaging.



Installation:



The  installed monitoring  system is based on an industrial datalogger connected to two gas flow meter sensors. The key factors are the installation environment and the properties of the gas to be measured:



1.  The NEXT Industries miniOMNIAlog datalogger (151 mm x 136 mm x 90) is required here due to the  need for an  external installation.  This compact instrument has an IP67-rated housing  so  it can  be  deployed  outside  control  cabinets  or  enclosures.  The  logger's  complete  conformal coating--a layer of transparent plastic film--acts  as protection  for the internal electronic boards against  moisture  and  other  contaminants.  This  ensures  that  the  miniOmnialog  can  withstand industrial environments and maintain its high-precision measurement over the long-term.



2.  The  gases  are  mainly  composed  of  methane  and  carbon  dioxide  (CO2),  but  hydrogen  sulfide (H2S)  and wet vapor are  also present. Since  this  can  have corrosive effects, technicians have to use specific gas flow sensors: two BFM mass flow meters. The flow meters are connected to the miniOmnialog's  4-20  mA  inputs.  One  monitors  the  digester  ouput  and  another  measures  the burned methane on the boiler.  Each  flow meter  has two 4-20 mA ouputs: one for the gas flow and another for the temperature.



Standalone Operation and Alarm Transmission:



This  datalogger  has  a  powerful  32-bit  CPU,  with  two  GB  (storing  4  million  measurements)  of  internal non-volatile  memory  that  provides  for  extended  autonomous  datalogging  capability.  Additionally  the device's electronic circuits are designed to reduce the power supply requirements to a minimum so that it  can  operate  for  several  months  (up  to  a  year  with  4  channels  sending  data  every  day)  using  the internal battery pack.



The  alarm-generation  capability  the  customer  requires  is  performed  by  the  miniOMNIAlog's  internal GPRS  wireless modem.  The  data  logger  can  be  configured  to  send  SMS messages  and/or  FTP  and/or emails based on the measured data. Users can also activate a relay output in case of alarm.



While  users  mainly  rely  on  the  logger's  wireless  connection  transmit  the measurement  data,  it's  also possible to download data using USB if desired.



Data Access from Smartphone and Tablet:



Users can remotely monitor the plant online via  smartphone  or tablet thanks to the OMNIAlog Cloud Web Portal. This optional cloud service enables users to monitor and control equipment and field devices quickly and efficiently.



Thanks to the cloud service users can drag and drop widgets to configure and build custom dashboards that display critical information  visible even from a distance.



Benefits:



The  miniOMNIAlog  datalogger  has  both  the  necessary  durability  and  small footprint  for  this deployment. With four  channels  and  the  internal modem  it's a cost-effective device. Additionally  the  OMNIAlog's  large  memory  is  a  useful  feature  for  the  plant's  need  to  document  flow data for certification.  Meanwhile the  Cloud service enables remote monitoring and mimic generation. These features will help the director fine-tune his process and improve yields.



For more information on the Next Industries miniOMNIAlog, more data logger models to log other values, or to find the ideal solution for your application-specific needs, contact a CAS Data Logger Applications Specialist at (800) 956-4437 or visit the website at www.DataLoggerInc.com.



Contact Information:

CAS DataLoggers, Inc.

12628 Chillicothe Road

Chesterland, Ohio 44026

(440) 729-2570

(800) 956-4437

sales@dataloggerinc.com

www.dataloggerinc.com

Contact This Company

All Topics