ECOMax_HE Automatic Heat Exchanger Tube Cleaning System (ATCS)
ECOMax_HE, the online solution to mitigate the fouling problem in the shell and tube heat exchangers. It keeps inner walls of tubes always clean by using cleaning sponge balls. It operates periodically at pre-defined intervals automatically. Our ATCS is maintenance free and designed to have long life & trouble free operation.
Applicable to all sectors of shell and tube heat exchanger, industrial factory, petrol chemical plant including condenser for chiller of HVAC air condition. The system is online operating all time, Maintain the cleanliness of tube surface so that the system will has good heat transfer efficiency, also reduce power consumption of the whole operation.
Injection Cycle :
The injection control valve opens and injection pump starts. Injection pump takes water from the Cooling Water inlet pipe and boosts the pressure in the Ball Collector (BC), where the cleaning sponge balls are resting. As soon as the pressure in the ball collector is boosted, the sponge balls are injected almost simultaneously at the heat exchanger tube sheet with the help of injection pump thereby giving effective spread to the sponge balls in various tubes, the sponge balls would pass through the tubes and clean the fouling /scales/deposits inside the tubes. Once the sponge balls come out of the heat exchanger tubes they are collected at ball trap & wait for the collection cycle.
Collection Cycle :
In the collection cycle, collection control valve opens and collection pump starts. Collection pump takes water along with the sponge balls from the Ball Trap, the sponge balls are arrested by the Ball Collector on the way back & water is sent into the Cooling Water outlet pipe. The entire process is a batch operation, automatically controlled by PLC and occurs periodically few times in an hour. These pumps run hardly for 1-2 minutes for injection and collection of sponge balls in each cycle.
Salient Features :
- Fully automatic, no manual intervention required
- Cleaning is done on continuous basis online
- Zero ball loss system, no balls can escape to cooling tower
- Ensures 100% clean tubes
- Single System for Multiple Chillers even if the Chiller capacity is different
- Smart System, gives an alarm for Sponge Ball Replacement
- Automatically operates a cleaning cycle on the running chiller
- User Friendly Graphical User Interface (GUI)
- Touch screen Multi Color HMI
- Indicates number of cleaning cycles on individual chiller
- Completes the cleaning cycle even if the chiller is stopped during the cycle
- No water wastage from the system
- No mixing of CW inlet and CW Outlet Water during operation
- Minimal pressure drop in the Ball Trap
- Negligible power consumption by the booster pumps
- Highly reliable as the system has less no. of control valves
- Cleaning Sponge Balls would never be in contact with pump impeller
- Compact, smaller foot print
- While venting air from Ball Collector, sponge balls can’t escape from Ball Collector
- Sight glass on the ball collector facilitates easy counting & monitoring of sponge balls
- No plant shut down for system installation
- Green Technology
- Results in up to 20% energy saving in HVAC chillers
- Results in up to 5% increase in power output in case of Power Plants
- Increases cooling capacity of HVAC Chillers
- Improves Condenser tube life
- Improves Compressor Life
- Avoids costly shutdown and downtime
- Eliminates offline cleaning completely
- Avoids harmful chemicals that are used for descaling
- Reduces Carbon Foot Print
- Cost effective technology and offers very attractive ROI, usually less than 1 year
Fouling is a universal problem in shell & tube heat exchanger. It is basically the accumulation of unwanted material on solid surfaces to the detriment of function. Fouling can be in the form of Scaling, Biological deposits/ Bio-filming, Slime which affects the heat transfer & poor heat exchanger performance.
Scaling/Chemical fouling :
The cooling water contains salts of calcium & magnesium. At elevated temperature salts of calcium & magnesium tend to precipitate & deposit on the heat exchanger surfaces. The chemical changes within the fluid cause a fouling layer to be deposited onto the tube surface. A common example of this phenomenon is scaling in a kettle or boiler caused by “hardness” salts depositing onto the heating elements as the solubility of the salts reduce with increasing temperature.
Mg(HCO3)2 + Heat = MgCO3 (Deposit) + CO2 + H2O
Ca(HCO3)2 + Heat = CaCO3 (Deposit) + CO2 + H2O
This type of fouling needs to be removed by chemical and mechanical means.
Biological fouling :
Bio-fouling is organic debris that adheres to inside diameter of tube surface or blocks the intake flow at the tube sheet. This is caused by the growth of organisms within the fluid which deposit out onto the surfaces of the heat exchanger. When this type of fouling occurs it is normally removed by either chemical treatment or mechanical brushing processes.
Deposition fouling :
This is when particles contained within the fluid settle out onto the surface when the fluid velocity falls below a critical level. Although the water quality is maintained because of the dusty surrounding in the industries, deposition fouling problem elevates. When this type of fouling occurs it is normally removed by mechanical brushing processes.
Corrosion fouling :
This is when a layer of corrosion products build up on the surfaces of the tube forming an extra layer of, usually, high thermal resistance material.
Effect of Fouling on HVAC Chillers
Contributing of fouling will effect in thermal resistance factor, this will increase electrical consumption and decrease efficiency.
The increase in electrical energy takes place in the compressor. Scale deposits will increase the thermal resistance causing higher refrigerant gas temperatures from the condenser. Higher refrigerant gas temperatures mean higher gas pressures, which require greater energy to compress the refrigerant. Therefore, there is an increase in the electrical power required to operate the compressor. Minimizing this potential energy loss requires monitoring of the daily energy consumed per ton of refrigerant/air conditioning being generated. This will allow you to recognize when inefficient operation is increasing due to deposit accumulation within your system.
Major manufacturers of air conditioning equipment generally design condensers and chiller heat exchangers to operate at a maximum “thermal resistance” or fouling factor of 0.0005. As a result, a deposit of only .036 inches (about 1/32”) corresponds to an increase in energy costs of over 30%!
This 30% increase in costs relates to a common calcium carbonate deposit. The actual heat transfer coefficient of a deposit depends on what it is. Iron deposits of the same thickness are greater insulators and therefore have lower heat transfer coefficients.
The cost savings example (below) shows the increased energy costs associated with scale deposits. Utilizing the example in this chart, you can plug in your facility’s equipment, energy cost per kWh and equipment operating hours. This will provide the total energy cost to operate your equipment for one year. Once you have ascertained your annual energy costs, you can apply the fouling factor that correlates to the current deposit thickness that exists within your equipment.
Cost Effect Chart from Fouling
Effect of Fouling on Power Plant Condensers
One of the major causes of lower vacuum is fouling inside the condenser tubes. Although treated water is used in the cooling towers, fouling of condenser tube is inevitable Fouling of the condenser tubes in the power plants cost millions to the owners/operators. Following graphs show the effect of lower vacuum on steam turbine efficiency & steam consumption in the turbines.
Installation picture of ECOMax_HE in various heat exchanger condenser
The system can be utilized for multiple units of heat exchanger that locate in the same area. The central control and ball distributing unit can automatically feed the cleaning balls to individual unit of heat exchanger with PLC control.