In the present environment due to the energy crisis and steep increase in the cost of energy and other input materials, it has become imperative to give a serious thought on how to make operations and equipment efficient towards use of energy and adopting latest technology equipment to retain the requisite competitive edge in the market, discusses KK Sharma of Invotech Industrial Solutions.
India was the second largest cement producer in the world in terms of cement capacity during 2019. Therefore, one can easily assume the amount of energy being consumed in cement production facilities and its wastage attributed to non-availability of proper technology to plug the leakages. We can find hundreds of research papers/case studies discussing the effect of different factors on energy consumption in cement manufacturing facilities. Some researchers also discuss this issue with the help of mathematical models. However, all the researchers more or less agree to the fact that "false air" not only but may be one of the factor of more energy consumption in cement industry. Further, based on the several studies in the field of operational audit, it can be concluded that production level can be improved and energy consumption reduced by reduction of "false air".
What is false air
False air is any unwanted air entering into the process system. The exact amount of false air is difficult to measure. However, an indicator of false air can be, increase of % of oxygen between two points (usable for gas stream containing less than 21 per cent of oxygen). Due to unwanted air, the power consumption increases and system's temperature decreases. Therefore, to maintain the same temperature fuel consumption has to be increased.
Impact of false air in cement plant:
False air intrusion points
In cement sector, generally false air intrudes in kiln section through kiln outlet, inlet seal, TAD slide gate, inspection doors and flap box. Similarly, in mill section false air intrudes through rotary feeder at mill inlet, mill body, mill door, flaps, expansion joints, holes of ducts and tie rod entry point.
In power sector, as margin is very less, cost- effectiveness plays an important role. Generally false air intrudes in CPP section through air pre-heater casing, boiler main door, fan casing, inspection doors, ESP main doors, ESP hopper doors, expansion bellows andducts. Similarly, in GPP section false air intrudes through main holes, hammering, bellows, rotary air locks, damper casing, expansion bellow, etc.
How to measure false air The formula used for measuring false air as under:
Atmospheric air normally has a content of zero per cent CO and 20.99 per cent O2. How to measure false air across pre-heater and mill: Based on the oxygen content and flow measurement at particular location, we can find out amount of false air across the pre-heater and mill circuit. For this purpose, % of O2 is measured at different locations, i.e.,pre-heater inlet and outlet, cyclone inlet and outlet, mill inlet and outlet, mill outlet to fan inlet, across bag-house or ESP.
False air detection through ultrasonic leak detector: Ultrasonic leak detectors often called sniffer, especially designed to find small leaks, are also being used in enclosed gas systems.Since ultrasonic gas detectors search for the sounds of leaks rather than escaping gases, they are able to detect leaks of any gas type. Though the device is unable to measure gas concentration, it is able to determine the leak rate of an escaping gas because the ultrasonic sound level depends on the gas pressure and size of the leak.
Functioning of ultrasonic leak detector: When gas escapes a pressurised line, it generates a sound in the range of 25 kHz to 10 MHz, well above the frequencies, the human ear is sensitive to but in a range easily identifiable to ultrasonic sensors. When the detector senses ultrasonic frequencies, they are isolated from normal background noise, amplified, and converted to a frequency audible to humans.
Detection principle: When a gas passes through a restricted orifice under pressure, it goes from a pressurised laminar flow to low pressure turbulent flow. The turbulence generates a broad spectrum of sound called ôwhite noiseö. There are ultrasonic components in this white noise. Since the ultrasound is loudest at the leak site, it can be detected very easily.
False air arresting
Usually cement plants use conventional methods to arrest false air, but these conventional methods are not reliable or permanent in nature. In fact, it works more like a silencer and just after a few days it gets damaged.
Therefore, Invotech Solution & Systems, which is now Invotech Industrial Solutions, a Rajasthan-based company, have come up with a unique product range after their years of research, which are being used in many cement manufacturing facilities. The client list figures renowned names like JK Cement, Dalmia Bharat, Nirma Group (Nuvoco Vistas), UltraTech, India Cements, Sagar Cements, Jaypee Group , Chettinad Cement and many more in the pipeline.
Invotech Industrial Solutions provides innovative and cost-effective industrial solution for arresting false air in cement plants, i.e.,pyro-process, raw mill, coal mill, cement mill section and bag-house. The "Arrest Master" (Product Name) is user friendly and safe to use.
Product range: False Air Arresting Compound
Arrest Master 1001: For upper cyclones, VRMs and power plants, shell temperature resistant upto 180 degree Celsius
Arrest Master 1002: For bag-house and bag filters top doors
Arrest Master 1003: For high temperature zone upto 500 degree Celsius.
Arrest Master 1004: For high temperature zone upto 800 degree Celsius.
Arrest Master 2001: For areas having vibrations, Shell temperature resistant upto 180 degree Celsius.
Properties of Arrest Master- false air arresting compound: Application of 'Arrest Master Series' brings down the level of false air and it is useful in all cement and power plants.
It hugely impacts plant productivity and contributes towards better housekeeping.Its other characteristics are:
Invotech Industrial Solutions keeps itself abreast of latest development in cement industry so as to cater the need of the Industry using latest technology and quality systems. Also, with a view to retain the requisite competitive edge in the market, participated in various seminars, details as under:
15th & 16th NCB International Seminar on cement, concrete & building materials held from December 5-8, 2017 and December 3-6, 2019 at Manekshaw Center, New Delhi.
National workshop-cum-technology exhibition to promote energy efficient and cleaner production for sustainable industrial growth held from March 8-9, 2018, at India Habitat center, New Delhi, where presented a technical paper on the "significant savings in energy through false air reduction" and received anaward for "upcoming entrepreneur in the field of energy efficiency".
14th Green Cementech 2018 held from May 17-18, 2018 at Hyderabad International Convention Center, Hyderabad where presented technical paper on "Enhancing Energy efficiency in Captive Power Plants by reduction of False Air".
Some of our articles also published in CMA's Technical Journal "Cement Energy & Environment", Vol. 17 No. 1 (Jan - Jun 2018) & Vol. 18 No. 1 (Jan - Jun 2019).
Invotech Industrial Solutions has recently developed a product called Arrest Master ABS for enhancing energy efficiency. It can be used to cool down the area rapidly with less air consumption but gives output 7 to 8 times as compared to normal air consumption. It is a special design Nozzle, works on Coanda Effect. Arrest Master ABS uses little amount of compressed air to deliver high volume output. Arrest Master ABS, a compressed air boost device, has been designed to give trouble free & maintenance free service as there is no moving part in it.It can also be used to cool down bearing housing, cutting hot material, cooling of lathe machine jobs etc.
Product highlights of Arrest Master ABS:
Substantial potential for energy efficiency improvement exists in the cement industry and in individual plants. Persistent efforts are also being made to continue to improve energy efficiency and reduce the energy cost for the cement industry for survival and growth. Our baby step towards arresting "false air" can contribute immensely towards cost cutting of cement manufacturing and improving energy efficiency. It is needless to mention that our efforts to improve energy efficiency will also minimise greenhouse gas and mitigate the environmental problems associated with cement production.
ABOUT THE AUTHOR: KK Sharma is from Invotech Industrial Solutions Near Shivam Hyundai, Parbatpura Industrial Area, Ajmer- 305001, Rajasthan. Tel: 8005521600/9001458666 Email: email@example.com | firstname.lastname@example.org Web: www.invotechsol.com