Descaling Pulp and paper Machinery - Solutions to Scale Buildup
Water plays an essential role within the pulp & paper industry. It’s not only used for cooling, but also contributes to a large part of the paper making process. In fact, water is utilized in 85% of all three main stages of paper production: pulp making, pulp processing, and paper/paperboard manufacturing. In a U.S. mill, the amount of water used per ton of paper can vary significantly, ranging from 4,500 to 17,000 gallons. However, around 90% of this water is eventually returned to its source, and only about 1% remains in the final paper product. Usually, paper mills source their water from places like wells, rivers, and lakes. This means the hardness of that water, depending on geographical location and source, can be very high in calcium content.
Due to the abundance of water required for the paper making process, mineral deposits can, and generally will accumulate quickly throughout the process. Though the majority of water is used within the process, there is a secondary side for equipment cooling which is equally critical to efficiency. This cooling water is fed to various types of equipment that require it for heat rejection. Some examples of this equipment are:
- Presses
- Digesters
- Scrubbers
- Condensers
- Head boxes
- Vacuum filters
- Chemiwashers
- Rolls, all types
- Cooling towers
- Vacuum pumps
- Air compressors
- Inter/after coolers
- Lime and mud pumps
- Heat exchangers/coolers, all types
- Green, White, and Black Liquor lines
When used in heating and cooling systems, the minerals within that water supply can fall out of suspension and plate onto the surface of your heat transfer equipment. The accumulation of these deposits can be difficult to remove, depending on the complexity of the equipment cooling passages. However, if these deposits are not removed, they will reduce efficiencies by increasing energy consumption and minimize capital equipment longevity.
Scale deposition commonly occurs in various stages of the pulp and paper making processes. It is an unwanted occurrence that causes many operational problems such as plugging of equipment, increased utility costs, lost production due to downtime, corrosion, and product defects. For example, calcium scale deposits within a green liquor line at one pulp mill increased so quickly, it effectively reduced a 4-inch diameter line I.D. to a 1-inch line I.D., resulting in the systems transfer pumps, rated to pump 260 gal/min, to go down to 60 gal/min. The pumping efficiency isn’t the only function effected, as the scale also acts as a major heat insulator and accounts for a 10% loss in efficiency of heat transfer in processes for every 1/16” thickness of calcium carbonate.
You don't have to wait for unplanned shutdowns or failures to get rid of hard water deposits. By charting your equipment performance with proactive daily logbooks, operational set points will identify performance loss early on. It is important to identify scaling at the early onset before the equipment goes out of operational specification. Detecting scale accumulations early avoids cooling channels from becoming completely plugged which will require a more elaborate cleaning procedure.
Chemical descaling agents and clean-in-place pump systems go hand in hand for effective, efficient deposit removal. It is equally important to have the correct GPM flowrate on your pump system as it is to have the correct descaling solution and cleaning procedure. If your flow rate is too low, you may not achieve sufficient movement in all the scaled areas to effectively remove all the deposits.
Goodway Technologies offers high quality descaling solutions for industrial cleaning applications that are formulated to complement any maintenance program. Our innovative solutions come in three variations which fall under the family name of ScaleBreak, ScaleBreak-MP and ScaleBreak-SS (made for stainless steel). These cleaning agents are designed for heavily scaled systems. Our goal is to ensure your equipment is cleaned effectively and safely depending on its base alloy. Our chemical scale removers are delivered in a concentrated form and diluted with water for use at your facility. These products are designed so the equipment can be cleaned in place without the added costs of disassembly. All our descaling solutions are biodegradable in their neat state, they are non-toxic and ship non-hazardous for minimized transportation costs.
Regardless of the equipment you need to clean, Goodway Technologies offers free descaling consulting. It is our goal to make sure you utilize the correct descaling solution and cleaning methodologies so you can achieve a successful result. Whether you’re cleaning a boiler, chiller, cooling tower, evaporative condenser, fluid cooler, heat exchanger or any other water operated piece of equipment, we have the experience to help.
Industrial and commercial facilities depend on robust preventive maintenance programs, and this includes the prevention and removal of water formed deposits.
Wondering where to buy descaling solution? You can learn more about Goodway Industrial Descaling Systems and Solutions here. Do you need help deciding which product to use? We’ve outlined which descaler may best meet your needs here.
Unsure how much descaler to use? No worries, you can use our https://www.goodway.com/resources/calculators descaling calculator to estimate descaler amounts and circulation times. But the resources don’t stop, we also have application specific procedures to walk you through your cleaning step by step. If you are still unsure and have questions, we offer free descaling consultation with an expert that has been involved with chemical cleanings for over 25 years.