GEA supports South African customer Mpact with a black liquor concentration and drying plant

Background information

Mechanical Vapor Recompression (MVR)
The operating costs for an evaporation plant are largely determined by energy consumption. Mechanical vapor recompression (MVR) and thermal vapor recompression (TVR) are technologies that GEA uses based on many years of experience. GEA provides customers with the optimal system tailored to their individual needs.

While steam jet compressors compress only a part of the vapor leaving the evaporator, mechanical vapor re-compressors (MVR) can re-circulate the entire vapor. The vapor is compressed – usually using electric motive power – to the pressure of the corresponding heating vapor temperature of the evaporator. The energy of the vapor condensate is often still used to preheat the incoming product.

Depending on the operating conditions of the plant, a small amount of additional steam or condensation of a small amount of excess vapor may be required to maintain the overall heat balance of the evaporator and ensure stable operating conditions, especially during start-up.

Single-stage centrifugal fans (supplied as high-pressure fans) are used in evaporation plants because of their simplicity and low-maintenance design. These machines operate at high flow rates and therefore handle large throughput volumes at compression ratios of 1:1.2 to 1:2, with typical speeds ranging from about 3,000 to 12,000 rpm. Multiple blowers can be used for higher pressure rise.

Decanter centrifuges for black liquor clarification
GEA supports its customers in the realization of pulp and paper plants with a comprehensive technology spectrum. Especially for the mechanical separation of sedimentation, centrifuges are an important component in the entire process flow. GEA's expertise includes the efficient separation of impurities or solids by centrifuges for solids and liquids.

> The use of a GEA decanter centrifuge can help maximize the yield of black liquor plant by efficiently separating the solids from the liquid, and the decanter centrifuge improves the subsequent process steps.

GEA decanter centrifuges are designed to operate with high efficiency and can contribute to energy savings in the production process. This aligns with sustainability goals and demonstrates environmental responsibility.

Recovery of marketable byproducts with Zero Liquid Discharge (ZLD) systems.
ZLD systems are designed to remove dissolved solids from wastewater and return distilled water to the process. GEA's ZLD technologies enable industrial processes to meet environmental regulations and are specifically designed to separate valuable salts from waste streams before disposal to generate added value.

To achieve complete ZLD, various technologies are typically combined. These include, for example, ultrafiltration, reverse osmosis, evaporation, crystallization, desalination, separation and drying. GEA can offer a complete portfolio of technologies to recover valuable by-products that can be commercialized.

For example, GEA has custom designed and supplied numerous ZLD treatment systems for coal-fired power plants and waste incinerators. These systems effect precipitation of heavy metals, evaporation with seeding (as an anti-scaling measure) and crystallization. In addition, GEA has many years of experience in dealing with corrosive materials, so each plant can be designed and built with corrosion-resistant materials as required.