**Case Study**
Chromium-containing Rinse Wastewater Treatment with Low-Temperature Heat Pump Evaporator in Guangdong
**Project Overview**
The client is a foreign-owned enterprise specializing in the production of various high-quality kitchen and bathroom accessories, automotive parts, door handles, and other products. The company integrates mold design and development, die-casting molding, punching, CNC lathe machining, automatic polishing, and professional electroplating surface treatment technology. Its product quality and technology are at the forefront globally, with products sold to Europe, Japan, the United States, and other regions.
**Project Disposal Pain Points**
The client’s production line for electroplating capacitors involves the following process: degreasing – acid activation – hard chromium plating – rinsing. The original disposal method involved neutralization and external discharge of rinse wastewater. Due to regulatory requirements, the client needed to resourcefully treat the rinse wastewater after hard chromium plating without discharging it externally.
**WSD Environmental Solution**
To achieve better reduction and resourceful treatment of wastewater, the client, after evaluating various options, ultimately chose the WSD low-temperature heat pump evaporator. The equipment features high automation, reducing personnel operations, high concentration ratio to reduce outsourcing costs and save costs, small footprint to reduce the area of wastewater stations, and high-quality treated effluent.
△ Site of WSD Low-Temperature Heat Pump Evaporator
**Disposal Effect**
The WSD environmental low-temperature heat pump evaporator produces distilled water after treatment, which can be returned to the production line for rinsing. The concentrated solution can be returned to the hard chromium plating tank for reuse. The main components of the plating solution in the hard chromium plating tank are chromium anhydride and a small amount of chromium mist suppressant. Increasing the concentration of the concentrated solution can enhance the concentration of chromium anhydride.
△ Comparison of Inlet and Outlet Water
**Comprehensive Benefits**
The WSD environmental low-temperature heat pump evaporator helped the client achieve resourceful treatment of wastewater, thereby improving work efficiency and reducing production costs.