Tag Archives: acid neutralization systems

Acid Neutralization Systems from Modutek

Posted on by

Acid Neutralization Systems from ModutekEditor’s Note: This article was originally published in July 2014 and has been updated with new information and reposted in Sep 2023.

Chemical waste from industrial manufacturing processes is often toxic and requires treatment before disposal. Aggressive chemicals represent a danger to local populations and the environment. An acid neutralization system adds chemicals to the chemical waste to reduce toxicity. When the right acid neutralization system is selected for a specific industrial process, the neutralized waste is often safe enough to flush down the municipal sewer.

Modutek designs and builds many types of chemical handling equipment, including self-contained acid neutralization systems that allow industrial customers to avoid using expensive third-party disposal companies. The systems Modutek provides are easy to install and feature low operating costs. They can be customized to match the customer application and fit available space. Such on-site chemical treatment and disposal is safe and cost-effective.

Understanding Acid Neutralization

Waste from industrial processes is often highly acidic—the liquid’s pH measures the waste’s acidity. A low pH means the waste contains strong acids and is highly corrosive. For example, an acidic sulfuric acid solution could have a pH of 3 and cause severe skin burns. The pH must be raised before the acidic waste can be disposed of safely.

A neutral pH of 7 is the pH of ordinary water, and a solution with a pH of 7 is no longer dangerous. The acid neutralization system must add enough alkaline chemicals to the acid waste to raise the pH to a safe level. A typical target pH of 6 to 9 is considered safe for disposal in the local sewer system.

Continuous Flow Systems versus Batch Neutralization Systems

Chemical waste can be neutralized continuously or in smaller batches. For continuous flow systems, the neutralizing chemicals are constantly added as the waste flow exits the process. The outflow is monitored to ensure that the pH remains within acceptable levels. For batch neutralizing systems, the chemical waste is collected and held in a collection containment tank. Once a given quantity is stored, the required neutralizing chemicals are added, and batch disposal can occur once the target pH is reached.

Continuous flow systems are most effective when the flow is relatively stable in terms of volume, pH, and nature of the waste chemicals. If significant variations occur, the continuous flow system may not be able to keep up, and impermissible values of pH may be reached in the outflow. Even when the outflow is relatively constant, the outflow pH may vary to some extent, so continuous flow systems are unsuitable when the outflow pH has to be within a narrow range.

Batch neutralization systems are lower cost but are focused more on applications with low volumes. The neutralization can be executed depending on the batch’s composition, and exact pH values can be attained. When waste is highly acidic or alkaline, batch neutralization systems can be more easily adapted to actual needs. In some applications, batch neutralization systems are the better choice.

Modutek Offers Systems that are Customized to Specific Applications

Modutek continuous flow acid neutralization systems can handle from 5 to 500 GPM and are available with two or three-stage operation, depending on the details of the process. The systems are unitized with larger systems skid-mounted for indoor or outdoor operation. Controls are fully automatic with microprocessor-based pH controls and a strip chart recorder. Chemicals are injected via two metering pumps per stage, and alarms can be sent remotely via the Internet. A final sample tank has a pH probe and chart recorder to document compliance with regulations.

Modutek’s batch sequence reactor systems can treat chemical waste, including heavy metals, metal anions, fluorides, and chelated/complex metals. Reactions can be programmed for multiple reagents and sequences. The systems are built with double containment and leak detection, and the contents of the built-in holding tank can be processed automatically. Safe operation is monitored with alarms for high and low pH, low reagent levels, high tank levels, and leakage. Modutek’s batch neutralization systems are designed for demanding chemical waste treatment and are the preferred option for process outflow with greatly varying characteristics.

Choosing the Right Neutralization System is Important for Environmental Protection

Selecting an acid neutralization system unsuitable for the process can have severe consequences both from a regulatory and environmental point of view. Modutek offers a free consultation to ensure that the chosen neutralization system is suitable for the application and performs as expected. Contact Modutek for recommendations on selecting the right acid neutralization system for your process application.

Chemical Handling for Wet Processing Equipment

Posted on by

Chemical Handling for Wet Processing EquipmentBecause wet processing of silicon wafers uses different types of chemicals, semiconductor manufacturing facilities need chemical handling equipment to store, deliver and dispose of the chemicals. A complete chemical handling system takes care of all aspects of chemical use and ensures chemicals are delivered to the process when and where needed.

For corrosive, toxic, or flammable chemicals, safe handling is critical. Most of the chemicals used in wet processing can’t be released into the environment without additional treatment. Neutralizing dangerous chemicals on site or storing them in safe containers until they can be transported to a treatment facility must be documented to comply with local regulations.

Since chemicals are often dangerous to the employees operating wet processing systems, the chemical handling equipment has to be designed to minimize spills and reduce employee exposure to chemicals and their fumes. A comprehensive chemical handling system can improve workplace safety, reduce spills and waste, and make chemical processes more efficient.

Chemical Delivery Systems Provides Your Process the Chemicals It Needs

Chemical delivery systems store the chemicals safely and then deliver the right quantities, mixtures, and concentrations directly to the production line. The amount of chemicals delivered has to be precise and repeatable. Successful wet processing often depends on the right mixture or concentration because etching, stripping, and cleaning can vary with the amount of chemicals in the bath. When processing batches, the amounts delivered must be precisely the same for each batch. With continuous processing, the chemicals delivered can’t vary over time.

Modutek has a complete range of chemical delivery equipment, from high volume systems for large continuous production lines to small batch operations. Chemicals can be stored remotely in large totes with a load cell interface or in 55-gallon drums near the wet process station. Modutek’s SolidWorks Simulation Professional and SolidWorks Flow Simulation applications can calculate the exact quantities of chemicals required, and the chemical delivery systems provide precisely the calculated amounts. These systems ensure that chemical handling and process repeatability are excellent.

Modutek’s Collection Systems Remove Used Chemicals from Processing Stations

Once a wet process such as cleaning, etching, or stripping is complete, the used chemicals must be removed from the process stations and collected. Chemicals can be stored in safe containers and sent to a company specializing in neutralizing and disposing of hazardous chemicals, or they may be neutralized on-site.

To collect the chemicals from processing stations, chemical lift stations can pump the chemical waste from the process tank to a storage container. Chemical carts, also called pump carts or collection carts, can be moved near the process tanks to empty smaller amounts of chemicals. Storage can range from small carboys to large collection tanks. For small volumes, waste chemicals can be pumped directly into a five-gallon DOT-approved carboy for subsequent shipping to an off-site neutralization facility.

Acid Neutralization Systems Ensure Compliance with Environmental Standards

Many wet process semiconductor manufacturing steps use strong acids in their process baths. The used acids must be disposed of safely without risks to employees, the general public, or the environment. Local regulations specify how acid waste must be treated to ensure that disposal meets these requirements.

As regulatory compliance becomes more complex, the costs of disposing of chemical waste off-site are increasing. Modutek can provide self-contained acid neutralization systems that are inexpensive to operate. These systems add neutralizing chemicals to the acid waste and track chemical use, waste pH, and discharge quantities. The systems can generate documentation for regulatory compliance and safely dispose of the neutralized waste.

Modutek Offers In-House Expertise for Selecting Chemical Handling Equipment

Modutek can help customers choose the right chemical handling equipment for their facility. In-house experts at Modutek can recommend equipment from a full line of chemical handling systems. Modutek can customize equipment for special applications and ensure that the systems meet customer needs. Contact Modutek today for t a free consultation to discuss your chemical handling needs.