Alfa Laval’s solution is the HPSHE. Fabrizio Palmeri, Manager, Market Unit Refinery, Alfa Laval: “An HPSHE continuously recovers maximum heat energy from bottom residues, while its single channel geometry gives it an ultra-efficient self-cleaning effect that prevents it from fouling.
“The HPSHE’s capability to withstand pressures of up to 100 bar and high temperatures, makes it an efficient process heat exchanger for Visbreaking, FCC, Desalting, Coking, H-oil, LC Fining and other processes. Although compact, it offers two to three times higher heat transfer efficiency than an S&T unit.”
An S&T normally requires cleaning several times a year. An HPSHE only requires servicing every four to five years and can be cleaned easily by backflushing, hydroblasting or in-line chemical cleaning. HPSHEs interiors are accessed by means of an easily opened front cover. This gives them a small service footprint unlike S&Ts, where space must be allowed for long tube bundles to be withdrawn and cleaned manually.
“Since the heat recovery performance of an HPSHE will not be reduced by fouling, extra process heat will not be required from the furnace,” says Fabrizio Palmeri. “This cuts fuel costs and reduces CO2 emissions from the refinery.” HPSHEs consume only a quarter of the pumping energy required by S&Ts. Also, as there should be no fouling to increase the pressure drop over the heat exchangers, no extra pumping energy will be needed either. This means substantial energy savings for the refinery.
“Our HPSHEs offer higher mechanical quality and are more robust than competing products,” says Fabrizio Palmeri. “They comply with main codes and regulations worldwide, including the coming API standard relating to spiral heat exchangers.”An HPSHE occupies one-sixth of the space of an S&T. Thus, long S&T trains can be replaced with just a few HPSHEs. Installation costs are lower, since less pipework and steel structures are needed.
Fabrizio Palmeri: “We are encouraging refineries throughout the world to make the technology conversion to HPSHEs in their sensitive processes and avoid fouling and related problems. With our help, customers in several countries have already achieved this, with excellent results in terms of process performance and their bottom lines.”