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Home My WebLink About1979-05-15; City Council; 5840; Dewatering equipment lease for Encina facility> VC-*X s~- i CITY OF CARLSBAD -^J "j AGENDA BILL NO. ^T ft*/ O Initial: ^ DATE: May 15, 1979 „ ,^^.. \J ft% Dept. Hd. C. Atty DEPARTMENT: Water Pollution C. Mgr. SUBJECT: Lease of Mechanical Dewatering Equipment for the Encina Water Pollution Control Facility CONTRACT NO. 1067 Statement of the Matter At their April 25, 1979 meeting, the Joint Advisory Committee authorized the utilization of budget contingency funds for the lease and installation of a dewatering device. The lease would be arranged such that it could be can- celled on 30 days notice should funds not be approved in the Fiscal Year 1979- 80 Budget for continuation of the contract. Adequate funds are available in the approved Encina budget to facilitate this recommendation. Exhibits A. Memo to the Joint Advisory Committee dated April 16, 1979. B. Letter from C M Engineering Associates dated April 6, 1979. C. Resolution No. 5*7(0 (f approving specifications and authorizing the City Clerk to advertise for bids for the lease and installation of a mechanical dewatering device. Recommendation Adopt Resolution No. <^~ *7 (o (f approving specifications and authorizing the City Clerk to advertise for bids for the lease and installation of a mechanical de- watering device. Council Action: 5-15-79 Council adopted Resolution #5766 » approving specifications and authorizing the City Clerk to invite bids for the lease and installation of mechanical dwatering equipment for the EWPCF. w MEMORANDUM TO: Encina Joint Advisory Committee DATE: April 16, 1979 FROM:Les Evans, General Manager SUBJ : Temporary Dewatering Device The C M Engineering Solids Handling Study, which was prepared last year, recom- mended a course of action to deal with the digester foaming problem and to fa- cilitate rerating. The major recommendations included: 1. Convert Digester No. 1 to a fixed cover digester. 2. Convert Digester No. 3 to a primary fixed cover digester. 3. Upgrade the mixing system on Digester No. 2. 4. Revise the digester heating system to direct steam injection. 5. Install an additional dewatering device. Recommendations 1 through 4 were included in the fiscal year 1978-79 budget. The cost of an additional dewatering device was deleted from the budget for consider- ation at a later time - possibly as a contingency purchase. At this time, we have spent, or obligated, all approved capital outlay funds. There remains a contingency of §25,000. C M Engineering has investigated the possibility of leasing or purchasing a de- watering device and has developed the following alternatives: 1. Purchase a device at a cost of about §100,000. 2. Lease a device at a cost of about §2,000 per month. The co^t of installation of the device would be approximately §40,000 and could not be permanent due to the Phase III construction of a new dewatering building. Purchase of a device would not guarantee that it would be compatible with the equipment which will be installed during Phase III (we don't know who the low bidder will be). I have included §50,000 in the proposed fiscal year 1979-80 budget for the lease and installation of a dewatering device. It may not be enough. The JAC has the following alternatives: 1. Delay the acquisition of additional dewatering equipment until Phase III equipment is installed. -TO: Encina Joint Advisory Committee SUBJ: Temporary Dewat^^Lng Device April 16, 1979 Page 2 2. Lease or purchase dewatering equipment during fiscal year 1979-80. 3. Utilize contingency funds and begin making arrangements for the installation and lease of a device immediately. The lease would have to be cancelable on short notice should the lease funds in the fiscal year 1979-80 budget not be approved. RECOMMENDATION; Alternate No. 3 - Utilize contingency funds and begin making arrangement for the installation and lease of a device immediately. The lease would have to be can- celable on short notice should the lease funds in the fiscal year 1979-80 budget not be approved. LE/mgt c w CIVIL & ENVIRONMENTAL ENGINEERING . ENGINEERING ASSOCIATES LAND PLANNING AND SURVEYING. April 6, 1979 Mr. Les Evans Encina Joint Powers 6200 Avenida Encinas Carlsbad, CA 92008 Dear Les: Per our proposal of 26 March 1979 and the subsequent tentative agreement between C M and the City of Carlsbad, C M is proceeding with securing a temporary dewatering device to process the daily digested sludge vol- ume from the Encina WPCF. Manufacturers Contacted Based on previous studies and the subsequent report by C M entitled Solids Handling Studies and Improvements, four equipment manufacturers were contacted and requested to submit lease prices for their respective equipment. These included a IV Winkle beltpress, a 32 Carter beltpress, a 250 Kruger centrifuge and a 3700 Bird centrifuge. Each of the afore- mentioned pieces of equipment were tested by the C M staff either at the Encina WPCF or at other facilities on similar type sludges. The Kruger and Bird centrifuges have demonstrated their ability to consist- ently produce a 21% TS sludge while the Winkle and Carter presses con- sistently produced a 261 TS dewatered sludge. Of the manufacturers contacted only Carter and Kruger have equipment available for immediate installation. Bird proposed to retro-fit the existing Encina centrifuge with "H-Series" equipment and Ashbrook proposed to provide a Mark II Klampress instead of the requested IV Winklepress. Interim Sludge Handling Alternatives Based on the equipment available two alternatives exist. These are (1) lease the Kruger 250 centrifuge or (2) lease the Carter 32 belt press. Each of these alternatives would incorporate the use of the existing Bird centrifuge to serve for standby emergency dewatering. 550 West Vista Way • Melrose Center • Vista, California 92083 • Phone (714) 758-3680 225 E. Airport Dr. • P.O. Box 6087, San Bernardino, California 92412 • Phone (714) 884-8804 or (714) 825-9562 Mr. Les Evans April 6, 1979 Page Two The proposed Bird retro-fit and the Klampress are not being considered as viable alternatives. The retro-fit Bird machine would have a maxi- mum capacity of approximately 55-60 gpm which is less than the desired interim dewatering capacity of 70-75 gpm. In addition no standby de- watering equipment would be available for emergency situations. The Klampress belt filter is relatively new to the American market and has not been extensively evaluated to yield reliable performance or opera- tional data. It is C M's opinion that it would not be to the best interest of Encina to lease this particular press without "first hand" knowledge as to the performance and operational capabilities. The two alternatives are detailed in Table 1 while the associated costs are presented in Table 2. The costs presented in Table 2 are based on the assumption that the existing dewatering facility would be modified to accommodate the interim dewatering equipment. If the existing facility cannot be utilized due to future construction activities, an alternate site would have to be selected to accommodate the interim equipment. If an alternate site is required, an additional $25,000 would have to be allocated for both alternatives for construction of a concrete pad, relocation of chemical addition and electrical equipment and the pur- chase and installation of a sludge conveyor. Equipment Selection Based on the equipment available it is C M's recommendation that Encina secure the use of the Carter 32 - 1.5 M belt press. This recommendation is based on the following: (1) The costs analysis presented in Table 2 indicates equivalent expenditures for each piece of equipment. (2) The plant expansion and upgrading plans incorporate the use of belt filters for the ultimate dewatering system. The use of belt filters for the interim system affords the operators the opportunity to gain valuable operating experience or belt filter operations. (3) Previous on site investigations at Encina WPCF indicate belt filters are capable of consistently producing dewatered sludge concentrations of 25% TS or digested primary sludge. The possi- bility exists to reduce hauling costs by $60 per day if a de- watered sludge of 25% is consistently achieved because the Bonsall landfill site would be available for final disposal. This potential cost saving is not evident with centrifugation based on the on site experiments conducted by C M. ,#•*», x*"* >*** Mr. Les Evans April 6, 1979 Page Three C M is totally aware of the problems reported at the La Salina Oceanside treatment plant regarding the Carter 31 - 1.5 meter belt press. Many of the reported problems were due to the physical set-up of the facility. C M spent approximately two weeks at the Oceanside dewatering site and, concluded that the chemical conditioning system and feed controls were inadequate to provide consistent good operation. In addition, it is C M 's opinion that the problems associated with plugging of the reactors could be eliminated by weekly washing with a weak acid solution. The incorporation of a properly designed feed and chemical addition system in combination with routine ractor cleaning and design modifications by Carter on the 32 - 1.5 meter filter should ensure consistent and effec- tive operation. C M appreciates the opportunity to be of service and looks forward to working with the Encina personnel on this project. Very truly yours, C M ENGINEERING ASSOCIATES S. Murk Principal Engineer Environmental Systems Division JSM:bs Enclosures TABLE 1 ENCINA WPCF INTERIM SLUDGE HANDLING ALTERNATIVES ALTERNATIVE NO.1 A 1 B 2 A 2 B Equipment Manufacturer Type Model Sludge Dewatering Volume Time of Operation. Flow Rate Solids Load Sludge Disposal Dry Weight Wet Weight Wet Volume Method Stand- By Capacity . . . sod . . .hr/day ... pDm . . . Ibs/day . . . Ib/day . . . Ib/day . . .vd-Vdav Carter Press 32 30,000 7 70 7,500 7,100 28,400 16.8 on- site Existing Bird Carter Press 32 30,000 7 70 7,500 7,100 28,400 16.8 land fill Existing Bird Kruger Centrifuge 250 30,000 7 70 7,500 7,100 34,200 20.3 on- site Existing Bird Kruger Centrifuge 250 30,000 7 70 7 500 7,100 34,200 20.3 land fill Existing Bird TABLE 2 ENCINA WPCF INTERIM SLUDGE DEWATERING ALTERNATIVES COST ESTIMATE FOR 18 MONTHS ALTERNATIVE NO. 1A IB 2A 2B Dewatering Costs Capital 5 Installation (1) $ 15,000 15,000 15,000 15,000 ..$/d 27^ 27^ 27^ 27_ Power-Installed hp 13 13 35 35 -Auxilliary hp 11 11 9 9 $/d 5 5 10 10 Chemical (3) Ib/day 415 415 4T5~ 415" $/day 83 133 83 83 Operator (4) '.hr/day 5 3 4 2 $/day 50 3£ 40 20 Lease $/day 66 66 66 66 Maintenance $/day J5 _5_ _5 _5_ Disposal Costs Hauling $/day 0 160 0 160 Dumping $/day 20 100 2() 100 Total 18 Month Cost $ 140,200 260,600 137,400 257,200 256 476 251 479 (1) Includes cost for auxilliary equipment, engineering and installation. (2) Power required for auxilliary pumps, conveyor, etc. (3) Based on Aqua Ben 1124 polymer. (4) "A" alternatives include time for on site trucking. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 .15 16 17 18 19 20 21 22 23 24 25 26 27 28 RESOLUTION NO. 5766 A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF CARLSBAD, CALIFORNIA, APPROVING SPECIFICATIONS AND AUTHORIZING THE CITY CLERK TO INVITE BIDS FOR THE LEASE AND INSTALLATION OF MECHANICAL DEWATERING EQUIPMENT FOR. THE ENCINA WATER POLLUTION CONTROL FACILITY - CONTRACT NO. 1067 _ WHEREAS, the City Council of the City of Carlsbad has determined it is necessary and in the public interest to lease and install mechanical dewatering equipment at the Encina Water Pollution Control Facility; and WHEREAS, specifications for the furnishing of all labor, material, tools, equipment and transportation and other expenses necessary or incidental for said project, Contract No. 1067, have been prepared and filed in the office of the Encina. Plant Manager in the City of Carlsbad and are incorporated by reference herein; . NOW, THEREFORE, BE IT RESOLVED by the City Council of the City of Carlsbad as follows: 1. The above recitations are true and correct. 2. The specifications as presented are hereby approved. 3. The City Clerk of the City of Carlsbad is hereby authorized and di- rected to proceed to publish, in accordance with law, notice to contractors in- viting bids for lease and installation of mechanical dewatering equipment in accordance with specifications hereinabove referred to. PASSED, APPROVED AND ADOPTED at a regular meeting of the City Council held the 1 5th day of Mav _ > 1979, by the following vote, to wit: AYES: Councilmen Packard, Skotnicki , Anear, Lewis and Councilwoman Casler NoneNOES: ABSENT: None ATTEST:^ "( ^RONALD C. PACKARD, MAYOR ALETHA L. RAUTENKRANZ, CITY CLERK . (SEAL)