[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Fwd: RE: RE: refineries



Scott provides a practical answer to my concern.  However, there is a wide 
schism between those involved in energy reduction and those involved in 
pollution prevention.  While there have been many serious attempts to 
narrow the wide gap, few have been very successful to date.  Energy 
reduction projects (especially those involved in PINCH) are just 
that.  They are assessed only on the energy reduction.  The environmental 
folks can take care of the extra hazardous wastes (these are NOT potential 
wastes).  The modifications that Scott mentions to minimize or reduce 
fouling are often ignored because of the cost or the extra time to design 
them in.  I hope that I did not discourage people from seeking energy 
reductions.  I meant only to discourage energy reduction programs that are 
conducted totally independent of pollution prevention efforts.  It is 
likely that this will cause MAJOR battles.  Energy reduction folks know how 
efficient they can be.  They bristle when you ask them to back off a bit to 
minimize other wastes and life cycle impacts.  I still believe that 
successful pollution prevention (resources and materials) is a game of give 
and take.  One has to balance all the issues around the operation of the 
process.  While there are many like Scott that do this well, there are many 
more that will seek their way or the highway when it comes to the sanctity 
of energy reduction.  Who knows?  Maybe I have just had some bad 
experiences in this area and remain a bit sensitive as a result.  Maybe 
much of it was due to the use of pinch.  After all, who likes to be pinched?

Bob Pojasek

>Date: Sat, 19 May 2001 10:13:21 -0700
>From: "Butner, Robert S" <butner@BATTELLE.ORG>
>Subject: RE: RE: refineries
>To: 'Robert Pojasek ' <rpojasek@sprynet.com>,
>  "'p2tech@great-lakes.net '" <p2tech@great-lakes.net>
>Reply-to: Robert Pojasek <rpojasek@sprynet.com>
>X-Mailer: Internet Mail Service (5.5.2653.19)
>
>Bob, you raise a valid point, but with all due respect, without looking at a
>lifecycle trade-off, I'd hate to walk away from significant energy savings
>(and all of the resultant reductions in NOx, CO2, and fuel value) merely for
>a *potential* concern over fouling related wastes.  Energy integration of a
>refinery can lead to significant reductions in overall energy load so the
>amount of reductions in these wastes/emissions can be very significant.
>
>While fouling is a potential source of waste in any process environment,
>many heat exchangers operate in regimes of flow, fluid properties, and
>design such that fouling-related wastes can be significantly reduced or
>eliminated; further, some of the plate and frame designs and other
>exchangers designed to promote high turbulence can reduce fouling even in
>environments which otherwise might pose problems.
>
>Rather than dismiss energy integration (by whatever method) outright, a
>better approach might be to use pinch (or your favorite energy optimization
>method -- there are other approaches that will produce good results) to
>identify improved efficiency HX networks, then use a DfE screening approach
>to selectively implement the projects based on heat exchange scenarios, and
>to select heat exchange equipment appropriate to the processing environment,
>from a full lifecycle (including routine maintenance) perspective.
>
>The articles/checklists I suggested in my original post discuss design
>strategies for dealing with fouling-related wastes (including equipment
>design and materials selection, etc), but ignoring energy integration
>opportunities is probably NOT a good strategy for eliminating these wastes.
>
>
>SB
>
>-----Original Message-----
>From: Robert Pojasek
>To: p2tech@great-lakes.net
>Sent: 5/19/01 10:16 AM
>Subject: Fwd: RE: refineries
>
>You must be very careful using PINCH technology.  It helps flatten the
>energy curves by adding additional heat exchange devices.  These devices
>
>get fouled (reduced heat transfer capacity) and need to be cleaned
>often.  This cleaning creates additional hazardous waste.  While it is
>possible to reduce energy and lower benzene emissions, you must trade
>off
>this increase in hazardous waste.  I am not sure that the trade-off is a
>
>good one.  This was examined in the EPA-Amoco Yorktown Refinery project
>and, I believe, PINCH was NOT implemented.  The developers of the
>technology fail to tell you about the tradeoffs.  So who said P2 is
>easy?  This is a great example of energy reduction expertise operating
>independently of pollution prevention expertise.  One should not
>separate
>these items in practice.  However, it is often done.
>
>Bob Pojasek
>
> >Delivered-To: p2tech-outgoing@glc.org
> >Delivered-To: p2tech@great-lakes.net
> >Date: Fri, 18 May 2001 14:13:49 -0700
> >From: "Butner, Robert S" <butner@BATTELLE.ORG>
> >Subject: RE: refineries
> >To: 'Dana Codell' <danacode@engr.colostate.edu>,
> >         p2tech@great-lakes.net
> >X-Mailer: Internet Mail Service (5.5.2653.19)
> >Sender: owner-p2tech@great-lakes.net
> >Reply-To: "Butner, Robert S" <butner@BATTELLE.ORG>
> >List-Name: p2tech
> >X-Loop: p2tech
> >
> >Dana --
> >
> >though you may need to use a specialist to help you with the
>methodology, if
> >the refinery has not already done so they should consider evaluating
>the
> >plant using the so-called "Pinch" technology (see for example,
> >http://www.linnhoffmarch.com/Resources/WhatIsPinch/pinint1.htm).  The
>method
> >was pioneered by B. Linhoff, but has been applied and extended by
>numerous
> >others and is essentially a thermodynamic analysis method for
>identifying
> >opportunities for heat recovery in complex process plants.   This can
>often
> >be a very effective means of identifying significant energy use
>reductions
> >in plants, and has the advantage of a fairly high degree of industrial
> >acceptance.
>
>Bob
>
>Dr. Robert B. Pojasek
>Pojasek & Associates
>PO Box 1333
>E. Arlington, MA 02474-0071
>(v) 781-641-2422
>(f)  617-788-0288
>
>
>http://www.Pojasek-Associates.com
>rpojasek@sprynet.com