Garratt-Callahan Formula 9420
Operators and managers of industrial heating, cooling and ventilation water systems rely on water treatment to ensure heat exchange efficiency and to extend system life expectancy. However, operational changes or issues relating to treatment failures, corrosion, or scale formation may warrant cleaning. Water containing high amounts of silica, if not properly controlled often result in silica scale formation.
Removing silica and silicate-based deposits “safely” and effectively has always been a huge challenge in this industry. For decades, hydrofluoric acid (HF) and ammonium bifluoride (ABF) have always been the go-to solutions for removing these types of deposits. While HF and ABF can effectively mitigate these heat exchange impediments, their use poses great bodily risk to those responsible for equipment cleaning.
Injury Risk Due to Handling of HF and ABF
HF and ABF are corrosive chemicals. While effective for cleaning industrial equipment, they can cause permanent bodily damage, and in some cases even death. HF itself is not only a toxic acid but it is also a contact poison. When absorbed through the skin and eyes, it causes severe burns, which sometimes develop several hours after exposure and later manifests as skin ulcers. According to the CDC, “[breathing] hydrogen fluoride can damage lung tissue and cause swelling and fluid accumulation in the lungs (pulmonary edema).” Inhaling it disrupts the nervous system and leads to cardiac failure.
The long-term effects of HF exposure are life-altering. Prolonged healing time for skin damage can lead to severe scarring. Fingertip injuries can lead to persistent pain and bone loss in the hands. If inadvertently ingested, HF may lead to progressive narrowing of the esophagus and damage to the stomach. Chronic lung disease can occur from breathing it in, and should HF splash into the eyes, visual impairment and even blindness can result. ABF is not much different in its deleterious effects on the human body.
Like HF, ABF is classified as a health hazard by the National Institutes of Health (NIH). Because it is water soluble, ABF is often considered by users to be a safer alternative to HF for cleaning scale from heat exchangers, cooling towers, chiller systems, steam boilers, and the like. However, this is not the case. In addition to irritating the skin on contact, inhaling ABF dust compromises the eyes and respiratory system. Like HF, it is toxic. Thus, a safe alternative is needed for removing one of the most common and damaging deposits from industrial equipment.
An Alternative for Silica/Silicate Scale Removal
Garratt-Callahan Formula 9420 (G-C 9420) removes scale build-up without risk of bodily injury. Termed a “safe acid,” this formulation does not pose the same harmful effects as HF and ABF to operators and managers tasked with maintaining industrial equipment. With an active ingredient recognized by the Environmental Protection Agency (EPA) as a safe alternative to HF, formula’s efficiency is evidenced by the following case studies.
Case Study 1: Premature Replacement of Chiller Tubes
Problem: Two 1200-ton chillers at a health care facility became fouled with deposits. The maintenance engineers anticipated spending thousands of dollars to replace the tubes.
Analysis: G-C’s analysis of the deposits in its CA ELAP-certified lab found that silica comprised 1/3rd of the deposits.
Solution: A solution of G-C 9420 was circulated through the chillers for six hours, removing 25 percent of the deposits. Subsequently, a fresh solution was further added, circulated for another six hours, removed all but a loose amount in the tubes. Manual tube brushing easily removed the remaining residue. The company avoided expensive replacement of the chiller tubes.
Case Study 2: Replacement of Chiller Problem: A customer experienced severe silica and silicate-based build-up in a chiller and faced replacing it to restore operations. The BEFORE picture shows the extensive deposit accumulation.
Solution: After running G-C 9420 through the system it started running at a “usable operational condition” (see AFTER image). Continual improvement was achieved through an effective online silica descale and control program. The cleaning and treatment programs extended the life of the chiller, and the customer avoided equipment replacement.
Case Study 3: Inefficient Plate and Frame (P&F) Heat Exchanger Operation
Problem: Two sets of P&F heat exchanger plates from a facility were fouled with deposits significantly impeding the equipment heat exchange efficiency. Analysis: G-C conducted tests in its CA ELAP-certified lab and identified the deposits from both samples to primarily consist of silica scale, with one set constituting a denser deposit with some iron oxide in the matrix. These plate and frame heat exchange plates were sampled and immersed in a solution of G-C 9420 at 75oF for 3 hours. The AFTER pictures (small area on the right side of the samples pictured) show complete removal of the deposits.
HF and ABF can cause severe skin burns that penetrate deep into the tissue and leave permanent scarring. Their toxicity affects the lungs, leading to life-long breathing difficulties as well as damage to other major organs. G-C 9420 contains an active ingredient recognized by the EPA as a safe and effective alternative to HF and ABF in removing silica/silicate-based deposits from industrial equipment without risk of bodily harm. Finally, engineers and service companies in institutions and commercial facilities can enhance the operational efficiency of heat exchange and process water systems with necessary cleanings without risking life-altering injuries to themselves and their colleagues.