Analysis of the energy consumption of industrial dry cleaning machines

General Manager of Beijing Yousa Washing Equipment Co., Ltd. Xu Gendi

Energy conservation is an ancient and eternal topic, as well as a frequently discussed and ever-renewing topic for our generation and future generations. Since the 17th National Congress, the central and local governments have regarded pursuing a resource-saving industrialization path as a basic national policy. All industries are implementing the scientific outlook on development, relying on technological progress and innovation, focusing on building a resource-saving and environmentally friendly society.
The domestic dry cleaning industry is developing rapidly, but due to its late start, the entire industry still has a large gap in energy saving and consumption reduction compared to developed countries in Europe and America. Many manufacturers pursue market share one-sidedly and, to reduce production costs, sacrifice energy consumption by minimizing various energy-saving configurations. Of course, some manufacturers lack innovative R&D institutions and do not know how to produce energy-saving products; most investors lack an overall understanding of the industry, have unscientific methods for inspection and certification, suffer from severe information asymmetry, believe one-sided statements and empty promises from sales personnel, and some investors focus more on initial investment costs while ignoring the later operating costs of dry cleaning machines.
Some time ago, during a market survey of dry cleaning machines in Beijing, many deeply felt this. Many dry cleaning shops chose very cheap but non-energy-saving dry cleaning machines, which could only be used as decorations because the energy consumption after starting was too high to bear the cost. So they simply pretended to do dry cleaning with water washing, or tried to avoid distillation or reduce the number of distillations. This resulted not only in clothes not being cleaned properly, but also in washing prices not increasing, high customer complaint rates, and even survival problems for dry cleaning shops, let alone profitability and market competitiveness.
Take a fully enclosed perchloroethylene dry cleaning machine as an example. A fully equipped dry cleaning machine has a direct cost of water, electricity, and oil between 0.6 and 0.8 yuan to wash a suit, while a machine with ordinary simple configuration costs between 1.5 and 2.8 yuan, with some even exceeding 3 yuan.
Why is there such a big difference in energy consumption for the same fully enclosed dry cleaning machine? Solving the problem of high energy consumption in dry cleaning machines is not only a social demand today but also a need for industry development and a must-consider for investors' vital interests. Investors should grasp model selection more scientifically and objectively and choose truly energy-saving and environmentally friendly dry cleaning machines.

Taking the water and electricity consumption of one wash cycle of a 13-kilogram fully enclosed perchloroethylene dry cleaning machine as an example, each time using the cleanest solvent to wash clothes, i.e., washing while distilling:

Note:
1. The above data is based on washing ordinary suits;
2. Set to continuous working state;
3. Indoor temperature above 20℃;
4. Cooling water is tap water below 28℃;
5. Washing and distilling simultaneously, that is, each time washing with distilled clean solvent, washing and rinsing once each, washing twice in total (this washing procedure is commonly used in laundries in Europe and America, and only by using this procedure can a truly environmentally friendly and healthy laundry be achieved).

Where does such a large difference in energy consumption come from? How to determine whether the selected dry cleaning machine is truly energy-saving? It can be solved from the following aspects:

1. Energy consumption difference caused by different options of built-in and external heaters.
Taking a 13-kilogram dry cleaning machine as an example, to achieve normal distillation speed, a built-in steam generator requires only 6KW, while an external steam generator requires 15KW for the machine to work normally. Because the external piping and the external steam generator itself consume a lot of energy, resulting in low energy utilization efficiency.
2. Energy consumption difference caused by different spin-dry speeds.
Whether dry cleaning or water washing, the actual spin-dry speed of the drum basket is one of the main factors determining drying time and is an important energy consumption parameter. The higher the spin speed, the faster the drying. For a 13-kilogram dry cleaning machine, the drying time difference between 420 rpm and below 300 rpm is more than double. To achieve a spin speed above 420 rpm, the design and manufacturing process of the dry cleaning machine's structural components, materials, machine weight, center of gravity, and spin torque must meet strict requirements. For example, if the solvent tank's sheet metal is too thin, the machine body will shake and make abnormal noises at 420 rpm, and severe cases may cause weld seam cracks and other serious quality issues. High spin speed also raises requirements for the main drive structure, static or dynamic balance of the basket, and the quality of the sealing system. Using ordinary domestic bearings and oil seals may cause bearing seizure, oil seal rupture, and even leakage of the entire solvent pipeline and tank within two years, seriously affecting machine stability and service life.
These all require higher management standards for each process at the dry cleaning machine manufacturer's site. In the short term, many domestic manufacturers find it difficult to greatly reduce drying time by increasing the high spin speed of dry cleaning machines, thus achieving effective energy saving.
3. The energy consumption difference caused by the structure of the refrigeration system is even greater.
The refrigeration system usually consists of two components: cold pump coil and heat pump coil. Differences in total heat dissipation area and material seriously affect drying time and efficiency. Many manufacturers, to save production costs, remove the heat coil from the refrigeration system, eliminating this auxiliary heating device. Some even omit a series of control devices for refrigerant flow, temperature, and pressure in the refrigeration system. Manufacturers may save 4,000 to 13,000 yuan in manufacturing costs, but this difference causes investors to pay a heavy price in operation: each wash consumes over 300 kilograms more cooling water, more than 7 kWh more electricity, and longer drying times.
At the same time, the material of the cold pump coil and heat pump coil, whether aluminum or pure copper sheets, affects heat transfer ratio and thus drying time. The matching ratio of the selected compressor and accumulator capacity, and the ratio of compressor to refrigeration coil and heat pump coil heat dissipation area, all affect drying time and water consumption.
4. Practical experience shows that the volume of the basket relative to the weight of the laundry load is another important factor affecting drying efficiency.
If the load ratio is unreasonable, the drying airflow will be obstructed, the drying time will be prolonged, and electricity and water consumption will increase. Currently, European and American dry cleaning machines use a load ratio of 1:20. Below this ratio, not only does it affect washing quality, but it also greatly impacts drying efficiency and increases energy consumption; of course, exceeding this ratio causes excessive friction on clothes, affecting washing quality, especially increasing the washing risk for silk and leather products, which is meaningless.
5. The structural components of the drying air duct determine the overall drying time, especially noticeable in dry cleaning machines used for more than two years.
Large DC air volume and drying airflow, fast wind speed, quick drying; unreasonable airflow structure greatly affects the drying airflow volume, thereby affecting drying time and increasing energy consumption.
6. Extensive use of energy-saving devices. For example, fully equipped European and American machines require adding a #2 heat pump (which uses distilled gaseous tetrachloroethylene, employing an automatic control system to directly dry clothes and achieve electricity savings).
Machines of the same model and brand using a #2 heat pump save more than 40% electricity during the drying process compared to those without it.
7. Adoption of various excellent energy-saving water valves.
For example, the use of temperature-controlled and pressure-controlled water valves, which automatically control the water inflow and outflow based on temperature to achieve water conservation.
8. Use of a specially customized dedicated frequency converter for dry cleaning machines.
A professional frequency converter not only simply controls the spin speed but adjusts and controls every parameter throughout the washing process, including forward rotation, reverse rotation, stop, drying, and spinning. It can also adjust over a hundred technical parameters such as frequency, torque, and voltage. The use of such a professional frequency converter can effectively save electricity during every stage of dry cleaning.
9. The optional automatic drying device can also save drying time, thereby greatly reducing electricity consumption.
The automatic drying device automatically adjusts drying time based on the load of clothes each time, achieving energy saving and consumption reduction.
10. A mature automatic washing program is very significant for reducing energy consumption and improving work efficiency.
A mature automatic washing program is not just a few randomly written washing programs stored in the computer as decoration, but one perfected and matured through thousands of customers' years of use and corrections, scientifically and reasonably developed in practice. Using such a washing program will greatly affect the energy consumption of the dry cleaning machine and improve the work efficiency of the dry cleaning shop.

Therefore, wise investors in the dry cleaning industry should consider not only the investment cost before investing but also calculate future daily operating costs. If a dry cleaning shop's annual laundry turnover is calculated at 400,000.00 yuan, washing about 25,000 sets of clothes, saving 1.00 yuan per set in washing costs will save 25,000 yuan annually just from dry cleaning; if the machine is used for ten years, it will save 250,000 yuan; if the dry cleaning shop's turnover doubles (a figure many shops can achieve after two to three years of operation), the ten-year savings will reach as high as 500,000 yuan. For large laundry factories or laundry centers, the profit from savings is even more considerable.

If you decide to choose an energy-saving dry cleaning machine, it is best to personally visit the dry cleaning machine manufacturer or a nearby sample dry cleaning shop with measurement conditions to conduct on-site measurements. The data obtained this way is more authentic and reliable than any verbal promises from manufacturers or suppliers.

It should be reminded that investors should prepare enough dry cleaning suits in advance and operate the machine personally to measure actual water usage, electricity consumption, and the highest spin speed (which requires a special speedometer). Measurements must consider drying temperature, the position of temperature measurement, and the temperature of the drying water inlet. If the dry cleaning machine uses an external steam generator, its electricity consumption should also be considered. To ensure washing and drying quality, true low-temperature drying must be used, measuring the drying temperature at the air inlet not exceeding 55°C, drying time, water usage, and electricity consumption. Comparing data from several sources makes it easier to judge whether the dry cleaning machine you choose is energy-saving.

In short, for investors, investment in the dry cleaning industry should have a new and long-term understanding, clearly recognizing the long-term impact of energy-saving and consumption-reducing products. Learn about the structure and functions of dry cleaning machines through as many channels and perspectives as possible, and use scientific and objective methods for selection. Choosing a good energy-saving dry cleaning machine can truly control your future daily operating costs of the dry cleaning shop or factory, increase profit margins, and make you more competitive in the dry cleaning market, standing undefeated.

At the same time, we call on dry cleaning machine manufacturers and suppliers to shoulder more social responsibility, increase investment in research and development funds, continuously develop energy-saving and consumption-reducing products, and stop sacrificing energy consumption for the sake of profit and market share, becoming villains of the era. We also hope that industry authorities will strengthen energy-saving and consumption-reduction publicity inside and outside the industry, allowing investors to understand the industry through multiple channels, reduce information asymmetry, increase governance and regulation efforts, make energy consumption indicators mandatory industry standards, and implement them in industry standards. This will help the domestic dry cleaning industry quickly narrow the gap with developed countries in Europe and America and achieve healthy and sound development.