TC Lines

We supply vapor liquid equilibrium data, liquid-liquid equilibrium data, the total reflux data of distillation towers and distillation tower simulators, that is, PR simulators.

When you need accurate

vapor-liquid equilibrium data,

you can count on TC Lines NZ Ltd.

TC Lines NZ Ltd. can offer VLE data with such accuracy that has never been available globally until now. It avoids the need for substantial experimentation wherever you or your clients are involved in the separation of mixtures using distillation and extraction towers.



TC line and PPM

TC Lines NZ Ltd. supplies accurate vapor-liquid equilibrium (VLE) data and liquid-liquid equilibrium (LLE) data. We predict such results using the pure correlation of infinite dilution activity coefficient data. Using the correlation, we established a pure prediction method (PPM) for binary systems including high-pressure VLE. The PPM is applied to a multicomponent distillation tower simulator, PR simulator.



Our products

(1)  VLE data and total reflux distillation data are supplied. Users can improve their binary parameters or interaction parameters built in their process simulators after fitting their data to our total reflux distillation data. We use hypothetical liquids above solute critical for fixing the activity coefficients and vapor pressures of hypothetical liquids [Kato, AIChE J. 51 (2005) 3275-3285]. Examples of high-pressure VLE products are shown as follows: HPVLE. Figure 1 shows examples of total reflux distillation data for the ethane and propylene system. Examples of low pressure VLE products are shown as follows; VLELLE. The pure prediction method enables us to predict the VLE of any binary system, even if they are not included in this list.


(2)  Groundbreading science delivers huge cost saving in propylene distillation purification (more). Propylene distillation tower simulator, PR simulator, is now supplied. Propylene purification is one of the most difficult distillation operations. It is because two hundred or more separation stages are needed and high-pressure vapor liquid equilibria (VLE) have been poorly predicted. Therefore, we applied the pure prediction method (PPM) to a new distillation tower simulator (PR simulator) for improving the propylene purification problems. Conventional commercial process simulators fail in predicting reliable high-pressure VLE. For the analyses of multicomponent distillation tower performance, the PR simulator predicts pressure (P) versus reflux ratio (R) and pressure versus reboiler heat duty relationships. The PR simulator can solve both the tower design and operation problems. Programming source codes are opened to users in order to sustain their highly flexible usage (authoring tools are provided from the Internet). The best merit of the PR simulator is that users themselves can change the program code to improve the VLE. Figure 2 demonstrates that an optimum pressure exists in the relationships between pressure versus reflux ratio and pressure versus reboiler heat duty, although a commercial propylene purification tower is operated at 1.67 MPa with 244 saparation stages, because a process simulator suggested the value using insufficient VLE prediction.


Prices, publications and patents

Contact us

Dr. Satoru Kato, Professor Emeritus (Tokyo Metropolitan Univ.)

C.E.O. of TC Lines NZ Ltd. and C.E.O. of TC Lines Co. Ltd., Japan
Phone: +64 275 188 323 (New Zealand)

Location: Avonhead, Christchurch, New Zealand



Fig. 1Stage number (N) vs. liquid phase mole fraction of ethane (x1) for the ethane (1) + propylene (2) binary total reflux distillation, (bottom x1=0.001; top x1=0.999)

Fig. 2 pressure (abscissa) vs. reflux ratio and reboiler heat duty (ordinate) of the propylene (1) + propane (2) + butane (3) system predicted using the PR simulator at the mole fraction of feed mixture xF=(0.967, 0.0325, 0.0004), the mole fraction of distillate xD=(0.992, 0.0071, 0.0009) and the mole fraction of bottom mixture xW=(0.156, 0.784, 0.06), () pressure vs. reflux ratio, () pressure vs. reboiler heat duty [GJ/h], () pressure vs. reboiler heat duty [GJ/h] of the propylene + propane binary and () pressure vs. reflux ratio of the propylene + propane binary.