The refrigeration principle of this natural gas absorption chiller (heater) is shown in Figure 1. The heating and cooling switch valve F5 is opened, and F6-F10 are closed. The diluted solution from the absorber is transported by the LTG solution pump, and heated by the low-temp heat exchanger and then enters the LTG. In the LTG, the diluted solution is heated and boiled by the flowing high-pressure and high-temp refrigerant vapor from HTG, and the solution is concentrated into an intermediate solution, an efficient process optimized in OEM chiller designs.
Most of the intermediate solution is transported by the HTG solution pump into HTG, after heated by the high-temp heat exchanger. In HTG, the fuel combustion releases heat to heat the LiBr solution to generate high-pressure, high-temp refrigerant vapor, and the solution is further concentrated into a concentrated solution. This step is performed in OEM chiller systems to maximize energy efficiency.
In the LTG, the high-pressure, high-temp refrigerant vapor from the HTG heats the dilute solution in the LTG and condenses into refrigerant water, which enters the condenser together with the refrigerant vapor generated in the LTG through throttling and depressurization, and then cooled into the refrigerant water corresponding to the condensing pressure by the cooling water in the condenser. These processes, integral to the OEM chiller design, ensure stable and consistent performance.
The refrigerant water in the condenser enters the evaporator after being throttled by the U-type tube, and then delivered by the refrigerant pump, sprayed on the evaporator tube cluster, absorbing the heat of the chilled water and evaporating, and then the temperature of the chilled water in the tubes drops, so as to achieve the purpose of refrigeration. The OEM chiller efficiently manages this evaporative cooling process to maintain optimal refrigeration capacity.
After part of the intermediate solution from the LTG mixed with the concentrated solution from the HTG, it flows through the low-temp heat exchanger and enters the absorber, sprays on the absorber tube cluster, and is cooled by the cooling water, and absorbs the refrigerant vapor from the evaporator at the same time and then becomes the diluted solution. The LiBr solution diluted by absorbing the refrigerant vapor in the evaporator is transported into the generator for heating and concentration by the generator pump, which completes a refrigeration cycle. The process is repeated by the OEM chiller, ensuring the evaporator can continuously produce low-temp chilled water for air conditioning or production processes.
• "Pre-stressed" HTG, to avoid pull-off of heat exchange tube: easy to maintain
The unique technology not only achieves the purpose of achieving thermal expansion reserve stress without heating, avoids the occurrence of heat exchange tube pull-out accidents when the HTG is out of liquid; but also facilitates maintenance. As experienced water chiller manufacturers, we incorporate these advanced technologies to enhance safety and ease of maintenance.
• Solution reverse series and parallel circulation technology: more full use of heat sources, higher unit efficiency (COP)
The solution reverse series and parallel circulation technology makes the solution concentration of LTG in the middle position, and the concentration of the concentrated solution in HTG is the highest. Before entering the low temperature heat exchanger, solution concentration will reduce after the intermediate solution mixing with concentrated solution. Then the vapor LiBr absorption chiller will obtain a large range for vapor discharge and higher efficiency, also be far away from the crystallization, which is safe and reliable. Our expertise as water chiller manufacturers ensures the application of this technology to maximize heat source utilization and unit efficiency.
• Interlock mechanical&electrical anti-freezing system: multi anti-freezing protection
A lowered primary sprayer design for the evaporator, an interlock mechanism which links the secondary sprayer of evaporator with the supply of chilled water and cooling water, a pipe blockage prevention device, a two-hierachy chilled water flow switch, an interlock mechanism designed for the chilled water pump and cooling water pump. Six grade anti-freezing design ensures timely detection of break, underflow, low temperature of chilled water, automatic actions will be taken to prevent tube freezing. As innovative water chiller manufacturers, we incorporate robust anti-freezing systems to ensure reliable and continuous operation.
• Auto purge system combining multi-ejector&fall-head technology: speedy vacuum pumping and high vacuum degree maintenance.
This is a new, high efficiency automatic air purge system. The ejector functions as a small air extraction pump. DEEPBLUE automatic air purge system adopts multiple ejectors to increase the air extraction and purge rate of unit. Water head design can help to evaluate vacuum limits and maintain a high vacuum degree. This design can provide a high vacuum degree for every part of unit at any time. Therefore, oxygen corrosion is precluded, service life time is prolonged and optimal operating status is maintained for vapor LiBr absorption chiller.
• Viable structure design: easy to maintain
Both the absorber solution spray tray and the evaporator refrigerant water spray nozzle can be disassembled and replaced, to ensure the cooling capacity during the life span.
• Automatic anti-crystallization system combining level difference dilution and crystal dissolution: eliminate crystallization
A self-contained temperature&level difference detection system enables unit to monitor excessively high concentration of the concentrated solution. On the one hand upon detecting an overly high concentration the unit will bypass refrigerant water to concentrated solution for dilution. On the other hand, the chiller utilizes HT LiBr solution in generator to heat concentrated solution to a higher temperature. In the event of a sudden power failure or abnormal shutdown, level difference dilution system will start rapidly to dilute LiBr solution and to ensure rapid dilution after power supply recovers.
• Fine separation device: eradicate refrigerant water pollution
The concentration of the LiBr solution in the generator is divided into two stages, the flash generation stage and the generation stage. The real cause of pollution is in the flash generation phase.The fine separation device finely separates the refrigerant vapor with solution in the flash process, so that the pure refrigerant vapor can enter the next step of the refrigeration cycle, eliminating the source of pollution and eradicating the pollution of the refrigerant water. As leading water chiller manufacturers, we ensure our systems utilize advanced separation technologies to maintain refrigerant purity and system efficiency.
• Fine flash evaporation device: refrigerant waste heat recovery
The waste heat of the refrigerant water inside the unit is used to heat the diluted LiBr solution to reduce the heat load of the absorber and achieve the purpose of waste heat recovery, energy saving and consumption reduction. Our expertise as water chiller manufacturers allows us to incorporate efficient waste heat recovery systems to enhance overall energy efficiency.
• Economizer: energy output boosting
Isooctanol with a conventional chemical structure as an energy boosting agent added to LiBr solution, is normally an insoluble chemical that has only a limited energy boosting effect. The economizer can prepare mixture of isooctanol and LiBr solution in a special way to guide isooctanol into generation and absorption process, therefore enhancing energy boosting effect, effectively reducing energy consumption and realizing energy efficiency.
• Unique surface treatment for heat exchange tubes: high performance in heat exchanging&less energy consumption
The evaporator and absorber have been hydrophilic treated to ensure even liquid film distribution on tube surface. This design can improve heat exchange effect and lower energy consumption.
• Self-adaptive refrigerant storage unit: Improving part load performance and shortening startup/shutdown time
The refrigerant water storage capacity can be automatically adjusted according to external load changes, particularly when unit works under partial load. The adoption of refrigerant storage device can shorten startup/shutdown time substantially and reduce idle work.
• Plate heat exchanger: saving more than 10% energy
A stainless corrugated steel plate heat exchanger is adopted. This type of plate heat exchanger has a very sound effect, a high heat recovery rate and remarkable energy saving performance. Meanwhile, the stainless steel plate has a service life of over 20 years.
• Integral sintered sight glass: a powerful guarantee for high vacuum performance
The leakage rate of the whole unit is lower than 2.03X10-9 Pa.m3 /S and three grade of magnitude better than the national standard which ensures the life of the China vapor absorption chiller.
• Li2MoO4 Corrosion inhibitor: an environment-friendly corrosion inhibitor
Lithium Molybate (Li2MoO4), an environment-friendly corrosion inhibitor, is used to replace Li2CrO4 (Containing heavy metals) during the preparation of LiBr solution.
• Frequency control operation: an energy-saving technology
Unit can adjust its operation automatically and maintain optimal working condition according to different cooling load.
• Tube broken alarm device
When the heat exchange tubes broke in unit at abnormal condition, control system send out an alarm to remind operator to take actions, reduce damage.
• Extra long lifetime design
The designed service life of the whole unit is ≥25 years, reasonable structure design, material selection, high vacuum maintenance and other measures, guarantees the long service life of unit.
• Fully-automatic control functions
The control system (AI, V5.0) is featured by powerful and complete functions, such as one-key startup/ shutdown, timed startup/shutdown, mature safety protection system, multiple automatic adjustment, system interlock, expert system, human machine dialogue(multi languages), building automation interfaces, etc.
• Complete chiller abnormality self-diagnosis and protection function
The control system (AI, V5.0) features 34 abnormality self-diagnosis&protection functions. Automatic steps will be taken by system according to level of an abnormality. This is intended to prevent accidents, minimize human labor and ensures a sustained, safe and stable operation of unit.
• Unique load adjustment function
The control system (AI, V5.0) has a unique load adjustment function, which enables automatic adjustment of unit output according to actual load. This function not only helps to reduce startup/shutdown time and dilution time, but also contributes to less idle work and energy consumption.
• Unique solution circulation volume control technology
The control system (AI, V5.0) employs an innovative ternary control technology to adjust solution circulation volume. Traditionally, only parameters of generator liquid level are used to control of solution circulation volume. This new technology combines merits of concentration&temperature of concentrated solution and liquid level in generator. Meanwhile, an advanced frequency-variable control technology is applied to solution pump to enable unit to achieve an optimal circulated solution volume. This technology improves operating efficiency and reduces startup time and energy consumption.
• Cooling water temperature control technology
The control system (AI, V5.0) can control and adapt the heat source input according to cooling water inlet temperature changes. By maintaining cooling water inlet temperature within 15-34℃, unit operates safely and efficiently.
• Solution concentration control technology
The control system (AI, V5.0) uses a unique concentration control technology to enable real-time monitoring/control of concentration and volume of concentrated solution as well as heat source input. This system can maintain unit under safe and stable at high concentration condition, improve unit operating efficiency and prevent crystallization.
• Intelligent automatic air extraction function
The control system (AI, V5.0) can realize real-time monitoring of vacuum condition and purge out the non-condensable air automatically.
• Unique shutdown dilution control
This control system (AI, V5.0) can control operation time of different pumps required for dilution operation, according to the concentration of concentrated solution, ambient temperature and remaining refrigerant water volume. Therefore, an optimal concentration can be maintained for the unit after shutdown. Crystallization is precluded and unit re-start time is shortened.
• Working parameter management system.
Through interface of this control system (AI, V5.0), operator can perform any of following operations for 12 critical parameters relating to unit performance: real-time display, correction, setting. Records can be kept for historical operation events.
• Unit fault management system.
If any prompt of occasional fault is displayed on operation interface, this control system (AI, V5.0) can locate and detail fault, propose a solution or trouble shooting guidance. Classification and statistical analyses of historical faults can be conducted to facilitate maintenance service provided by operators.
Deepblue Remote Monitoring Center collects the data of the units distributed around the world. Through the classification, statistics, and analysis of real-time data, it displays in the form of reports, curves, and histograms to achieve an overall overview of equipment operating status and fault information control. Through a series of collection, calculation, control, alarm, early warning, equipment ledger, equipment operation and maintenance information and other functions, as well as customized special analysis and display functions, the remote operation, maintenance, and management needs of the unit are finally realized. The authorized client can browse the WEB or APP, which is convenient and fast.
Chilled Water Outlet Temperature
Besides the specified chilled water outlet temperature of a standard chiller, other outlet temperature values may also be selected, but the min Temp. Should be no lower than -5℃.
Vapor Parameter
Please specify the relevant parameters of the vapor when ordering, such as pressure, flow rate, vapor overheating etc.
Pressure Bearing
The maximum pressure of chilled water/cooling water system is 0.8MPa. If the actual pressure of the water system exceeds this standard value, a HP unit chiller should be used.
Unit Qty
Based on the demand for A/C cooling or industrial process cooling, if there’s more than 1 unit required, the unit capacity and QTY should be comprehensively considered according to maximum operation load and partial load.
Control Mode
The standard China vapor absorption chiller is equipped with an Al (artificial intelligence) control system that enables automatic operation. Meanwhile, there are a number of options available for the customers, such as control interfaces for the chilled water pump, cooling water pump, cooling tower fan, building control, centralized control system and IoT access.
Notice
Please refer the “Model Selection Sheet” when ordering. Hope Deepblue will assist you to make the reasonable choice.
Item | Qty | Remarks |
Main unit | 1 set | HTG, LTG, condenser, evaporator, absorbor, solution heat exchanger, and auto purge device |
Vapor regulation valve | I set | |
Canned pump | 2/4 set | Different quantity according to difference figuration |
Vacuum pump | 1 set | |
LiBr solution | Adequate | |
Control system | 1 kit | Including sensor&control elements (liquid level, pressure, flow rate and temperature), PLC and touch screen |
Frequency converter | 1set | |
Commissioning tools | 1 kit | Thermometer and common tools |
Accessories | 1 set | Refer to Packing List, which can meet the demand for 5 years maintenance. |
Documents | I set | Including Quality Certificate, Packing List, User Manual, Accessories’ User Manual, etc. |
Heat source | Vapor | When placing an order, please specify the vapor pressure. If the vapor is overheated, please specify the overheating temperature. | |
Special order | HP type | When the Chilled water/cooling water ≥ 0.8MPa, a HP water chamber may be adopted. The pressure bearing capacity can be 0.8-1.6MPa or 1.6-2.0MPa. | When place an order, please specify the following details in the contract or annexes: QTY, parameters and any other requirement of a special order. |
Big Delta Ttype | Chilled water inlet/outlet Delta T is 7-10℃. | ||
LT type | The chilled water outlet temperature can be -5℃ to meet the requirements of special processes. | ||
Split type | Limited by the size of the user's site , the main body and the HT generator can be transported separately. | ||
Vessel-applied type | This type applies to occasions with slight wobbling. Seawater can be used as cooling water. |