Unit operations are process in which only physical changes and not chemical changes takes place, such as mixing, blending, crushing distillation, *etc*. Unit operations are a consistent set of building blocks that can be used to design a whole chemical process. The unit operations design is to provide method and structure to the synthesis and analysis of chemical process, as well as a rational and systematic path for performing process design calculations.

Figure 1. Common unit operations in ethanol production plants. (Kumar, D.; Murthy, G.S. 2011)

### Our Services

Alfa Chemistry provides design of individual and interconnected unit operations for you. Our unit operations design includes the application of process simulators, pseudo-eulerian formulation and computational fluid dynamics to meet your needs. Our design of individual and interconnected unit operations services include the following:

In chemical process engineering, we use computational tools which are called process simulators to establish models by using predefined unit operations (e.g. mixing, distillation, heating) from the library of the process simulator.

The design of unit operations is presented in terms of elements/parameters constructively aligned with the cognitive process required in problem solving.

Our scientists have designed and validated a pseudo-eulerian formulation (PEF) which is applicable to any unit operation that can be modelled using a system of ODEs. In addition, our PEF allows the accurate estimation of the concentration or temperature profiles of complex unit operations such as a multiphase and multicomponent reactor system.

We can use computational fluid dynamics (CFD), a combined mathematical and numerical approach, to analyze the process parameters affecting the chemical processes. Moreover, we apply CFD to evaluate crucial segments influencing the quality of production.

### Our Capabilities

Alfa Chemistry has rich experience in providing various approaches to solve design problems of individual and interconnected unit operations in the chemical engineering processes.

- Applied hydraulics

1. Our scientists fully consider basic engineering principles required to handle fluid in plant operations.

2. We have designed detailed pipeline hydraulic design procedures with the use of a typical design module for pressure vessel.

- Mass transfer and absorption

The general subject of mass transfer can be divided into four broad areas such as molecular diffusion in stagnant media, molecular diffusion influids in laminar flow, eddy diffusion or mixing in a free turbulent stream, and mass transfer between two phases.

- Distillation

1. Fundamental principles, relationships, formulas and methods of distillation and calculation of the number of stages required for both binary and multi-component systems are taken into consideration.

2. Basic problems of design associated with physical, chemical properties and hydraulic phenomenon inside the unit are also considered.

- Adsorption

1. The fundamentals of gas phase and liquid phase adsorptions are considered in which the driving force here is the ratio of the concentration to the solubility of the compound.

- Extraction and leaching

We consider processes involved in extraction and leaching, factors influencing, the processes and parameters with graphical methods of solving problems associated with the process.

- Heat transfer

Various modes of heat transfer and their applications to solving practical industrial problems are considered.

### Our Advantages

- Other unit operations processes such as pumps, fans, compressors, drying, evaporation, crystallization, refrigeration are also involved in our design strategies.
- Our teams have rich experiences in performing computationally-efficient numerical method.
- We speed up the computation time of a process design or an optimization flowsheet by reducing the computation of the unit operation design problems.

Design of individual and interconnected unit operations facilities provides an effective way to optimize the chemical process. Our design of individual and interconnected unit operations services remarkably reduce the cost, promote further experiments, and enhance the understanding of chemical process for customers worldwide. Our personalized and all-around services will satisfy your innovative study demands. If you are interested in our services, please don't hesitate to contact us. We are glad to cooperate with you and witness your success!

Reference

- Kumar, D.; Murthy, G. S. Impact of pretreatment and downstream processing technologies on economics and energy in cellulosic ethanol production.
*Biotechnology for Biofuels*. 2011, 5.